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برندهای خوب قیمت های خوب برای بچه های خوب

پنجشنبه ۱۶ دی ۱۳۸۹
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اون کتاب قصه های خوب برای بچه های خوب رو که یادتونه 😉

یک موضوع در مورد بازار های فای هست که من دوست دارم در موردش بنویسم و قصدم این نیست ارزش کار کسی رو بیارم پایین و یا به بازار کسی لطمه بزنم. من دید خودم رو بیان میکنم و معتقدم فقط با نقد میشه مسیر رو تغییر داد پس مجبورم نگاه ام رو بنویسم شاید این بازار تغییری رو که من دوست دارم تجربه کنه. درسته ممکنه بیان آزاد عقاید با منافع عده ای تضاد پیدا کنه اما به هر حال هر کسی آزاده نظر و عقیده اش رو بیان کنه.

از نگاه من ما تو ایران یک بازار های فای مبتنی بر “عدم اگاهی” داریم و این عدم اگاهی تقابل بین دو گروه آئودیوفیل ها و فروشندگان هست که از نگاه من عدم آگاهی در هر دو گروه چنین بازاری رو بوجود اورده.

منظورم از عدم آگاهی اینه که ایده های ما رو تجربه تو فرایندی درست تشکیل نداده و بدتر از اون این ایده ها توسط منابع تجاری و غیر وابسته ای مثل استریوفایل شکل داده شده.

تو ایران فروشندگان برندهایی رو آوردند که هم تو قیمت های پایین و هم تو قیمت های بالا فقط بیشترین ستاره ها رو از مجلات گرفتند و از نگاه من هیچکدومشون به اندازه قیمتشون در مقایسه با دیگر برندهای خوب تو دنیا ارزش چندانی نداشتند. از نگاه من تنها برندی که قبلا تو ایران بوده و درست انتخاب شده بود Audio Note آقای فاطمی بود که از نگاه من بهترین صدایی هست که تو ایران میشه شنید.

من نمیخوام از کسی و فروشنده ای انتقاد کنم چون ممکنه اون زمان ها در گذشته امکان چنین چیزی نبوده باشه و همین که فروشندگان تو این بازار پردردسر تا همین جا هم جلو اومدند باید ازشون تشکر کنیم پس روی صحبت من انتقاد یکطرفه نیست بلکه نوشتن در مورد موضوعی هست که کمک کنه فروشندگان از این به بعد تغییرات مثبتی ایجاد کنند. من با آقای رحمانی که صحبت میکردم و همچنین با دیگر وارد کنندگان میدیدم اونها هم مشکلات خیلی زیادی رو تو این مسیر تجربه کرده بودند و با این شرایط حاکم شاید باید همه ما از این فروشندگان بابت سرمایه گذاری در این بازار تشکر هم بکنیم.

پس قرار نیست اینجا کسی رو محکوم و یا به ندانستن چیزی بی اعتبار کنیم و من تنها قصدم اینه بگم این بازار نیاز به تغییرات داره و ما میتونیم از این به بعد با استفاده از تجربه هامون و استفاده از منابع با ارزش اینترنتی در جهت مثبت قدم های با ارزشی برداریم.

بازار تا قبل از ورود دو شرکت تا چند سال پیش فقط و فقط برندهایی رو تجربه میکرد که تو مجلات ستاره داشتند و با ورود دو شرکت سه برند چینی با قیمتی مناسب وارد بازار ایران شد.

شرکتهایی که برندهای چینی رو آوردند به این فکر میکردند که میشه تو قیمت های معقول و پایین صدای بهتری بگیریم که بنظر من این ایده ایده بدی نبود و خود من هم شاهد این بودم که همین برندهای چینی به نسبت قیمتشون صداشون بهتر از برندهای پرستاره ای بود که تو مجلات میدخشیدند.

خب این قدم قدم خوبی بود و این سیاست نتیجه خوبی دربرداشت و این دستگاه ها جای خودشون رو تو بازار باز کردند اما واقعیت اینه که از نگاه من ما میتونیم یک قدم خیلی بهتر برداریم که بازار باز هم واکنش خوبی نشون بده.

بگذارید توضیح بدم چرا من معتقدم استفاده از برندهای چینی با احتمال زیادی اون نتیجه ای که باید بده رو از نگاه من نمیده .

ببینید سیستم صوتی های فای یک دستگاه الکترونیکی مثل گوشی موبایل و یا کامپیوتر نیست که ما اونرو مجموعه ای از امکانات بدونیم و خوشحال باشیم چینی ها با High copy قیمت رو میشکونند و یا با DIY ما مرزها رو در نوردیدیم. های فای یک سیستم ایست که با حس شنیداری ما در ارتباطه و بسیار بسیار مهم هست که اون سیستم های فای بر اساس ایده ای از لذت شنیداری ما طراحی بشه.

برای پیاده سازی درست یک سیستم های فای ما نیاز به طراحی داریم که ایده درستی از صدا داشته باشه و بفهمه داره چکار میکنه و تا اون طراح و ایده درستش نباشه ما نتیجه مطلوب رو نخواهیم گرفت. برای همینه رومی خیلی تاکید داره DIY هم در بیشتر مواقع بدلیل نبودن همون ایده و درک درست از صدا به نتایج خوبی نمیرسه.

های فای چه تو قیمت های پایین و چه تو قیمت های بالا ، اولین قدمش مبتنی بر ایده طراح هست و در قدم بعدی هنر اون طراح در پیاده سازی ایده اش.

طراح FM Acoustics به بهترین شکلی ایده اش رو اجرا میکنه و واقعا طراحش آدم فوق العاده حرفه ای تو طراحی سیستم های الکترونیکی هست اما چون اون طراح ایده درستی از صدا نداره نتیجه کارش خوب از آب درنمیاد و یا طراح آئودیو ریسرچ چون ایده درستی از صدا نداره حتی با ابزاری مثل لامپ هم نتیجه کارش خوب نیست.

من با DIY و یا برند چینی مخالف نیستم و این رو قانون نمیدونم که نتیجه کار هر دوشون همیشه خوب نیست اما حرف من اینه صدای خوب از ایده درست و بعد پیاده سازی درست میاد نه از نداشتن ایده و سرهم کردن یک سری المان مرغوب.

یک DIY و یا یک برند چینی که در بیشتر مواقع طراحش فقط بر مبنای یه چیزی رو سرهم کردن میره جلو و نه ایده ای از صدا داره و نه تو پیاده سازیش از خودش ابتکاری داره (نقشه بیشتر این برندهای چینی و ساخته های DIY از روی نقشه های دیگران و موجود هست) و فقط تمام تبلیغش اینه که ما از المان های بهتری استفاده میکنیم طبیعتا نتیجه اش اون جوری که باید از آب در نمیاد.

بعد از داشتن یک ایده درست از صدا یک طراح باید ساختار طرح رو مشخص کنه و تو این مسیر بفهمه چه توپولوژی و مداری میتونه اون ایده ای که در ذهن داره رو به بهترین شکل اجرا کنه و در قدم آخر انتخاب المان هاست. از نگاه رومی انتخاب طرح و توپولوژی مدار اهمیت بیشتری از انتخاب المانهایی مثل خازن و مقاومت داره و بعد از اینکه طرح درست انتخاب شد ما به سراغ انتخاب المان ها میریم اونم بر مبنای ایده ای که از صدا داریم و نه چیزی که بازار پیشنهاد میکنه.

اکثر برندهای چینی و یا ساخته های DIY پشتشون ایده درست یک طراح نیست و طرح مدارشون بر مبنای مدارات معمول تو بازار هست و فقط به نسبت قیمتی که دارند از المان های بهتری توش استفاده شده. بنابراین نتیجه کار نمیتونه عالی باشه و فقط میتونه نهایتا بهتر از وضعیت بازاری باشه که توش برندهایی بر مبنای ستاره های مجلات انتخاب میشن.

من طراحانی رو تو دنیا میشناسم که بخاطر عدم شهرتشون دستگاه های خیلی خوب و ارزونی رو میسازند (مثل Decware) و فروشنده ها بجای آوردن برندهای چینی میتونند بروند سراغ این افراد.

تو قیمت های بالا هم دقیقا همینطوره و فروشنده ها بجای آوردن برندهایی مثل سولوشن میتونند بیشتر وقت بگذارند تا چیزهای بهتری پیدا کنند. باور کنید من از اتفاقات خوب مینویسم و اگر کسی بره بجای برند KR برند Lamm بیاره و بجای سولوشن برند Concert Fidelity  بیاره 100 بار همه که شده تو سایتم ازش حمایت میکنم.

اما نکته ای که خیلی مهمه اینه که یک آئودیوفیل هم باید بفهمه چه ایده ای درسته تا بتونه هماهنگ با تغییرات مثبتی که یک فروشنده ایجاد میکنه به جلو بره و این یک رابطه دو طرفه است که فقط با آگاهی هر دو طرف میتونه نتیجه مثبتی داشته باشه.

باز هم تکرار میکنم من از نوشته هام نه دنبال تامین منافعم هستم و نه بی ارزش کردن کار کسی و نه آزرده کردن خاطر کسی، بنظر من همه کسانی که تو این فضا زحمت میکشند شایسته تقدیر هستند و من این حق رو به همه میدم که آزادانه نظراتشون رو بیان کنند. معتقدم اومدن برندهای چینی تو زمان خودش اتفاق مثبتی بود و حالا میتونه این حرکت با تبدیل به حرکتی بهتر آینده بهتری رو برای همه رقم بزنه.

بنابراین نوشته های من زحمات و تلاش هیچ شخص یا گروهی رو زیر سوال نمیبره و فقط تلاشی است در جهت بهتر شدن اون حرکت. معتقدم با آگاهی میشه بهتر از قبل حرکت کنیم و نتیجه بهتری از زحماتمون بگیریم.

خوش باشید

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بابی فارل خواننده مرد گروه «بانی ام» درگذشت

پنجشنبه ۱۶ دی ۱۳۸۹
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من کارهای این گروه موسیقی Boney M رو خیلی دوست دارم خصوصا اون آهنگ ددی کولشون که مطمئنم همتون شنیدید محشره.

همونجوری که سیستم های صوتی قدیما با LP و سینگل ترایودها و هورن و ریل صدای خوبی میدادند انگار خواننده ها و گروه های موسیقی قدیمی هم بهتر از گروه های امروزی بودند.

هر چی میره جلوتر کمتر صدایی میشنویم که دوست داشتنی باشه.

آفتاب مطلب زیر رو نوشته :

http://www.aftabnews.ir/vdchkqnzw23nz6d.tft2.html

آفتاب: بابی فارل، خواننده گروه معروف بانی ام (Boney M)، که در دهه هفتاد میلادی از محبوب‌ترین گروه‌های موسیقی در اروپا بود، روز پنج‌شنبه در هتلی در روسیه درگذشت. فارل هنگام مرگ ۶۱ سال داشت.

جان سین، مدیر برنامه‌های فارل اظهار داشت این شخصیت هنری نامدار چهارشنبه شب بر طبق برنامه ای که اعلام شده بود در پیترزبورگ به روی صحنه ظاهر شد.

وی هم در آغاز برنامه خود و هم در پایان آن از مشکلات تنفسی خود شکایت کرد.

کارهای گروه بانی ام در سال‌های هفتاد میلادی بارها در صدر جدول پر فروش ترین آهنگ‌های اروپا جای گرفت و ۱۵ بار در آلمان پرفروش‌ترین گروه شد.

در بریتانیا نیز نزدیک به دو میلیون نسخه از «کنار رودهای بابل» به فروش رفت.

بانی ام نخستین گروه موسیقی شد که به وسیله یک رهبر اتحاد جماهیر شوروی (لئونید برژنف) برای اجرا به شوروی دعوت شد.

این گروه یک هواپیمای نظامی از لندن به مسکو عزیمت کرد و در برابر ۲۷۰۰ تماشاگر روسی در میدان سرخ برنامه اجرا کرد.

آلفونسو (بابی) فارل در ۱۵ سالگی خانه خود را در جزیره آروبا در کارائیب ترک کرد و به عنوان ملوان در یک کشتی به کار پرداخت.

بنا بر شرح حال رسمی‌اش، او سپس راهی نروژ و آلمان شد تا به شغل دی جی مشغول شود.

در ۱۹۷۴ گروه بانی ام که کارهای آن عمدتاً توسط فرانک فاریان، ترانه سرا و خواننده آلمانی اجرا و ضبط شده بود، فارل را به عنوان چهره اصلی گروه برگزید.

این گروه که مقر آن آلمان بود، به‌زودی در سال ۱۹۷۶ با کارهایی مانند «ددی کول» ((Daddy Cool و «سانی» Sunny) ) درخشید.

فارل و سه خواننده زن در ۱۹۸۶ از هم جدا شدند و فارل که در آمستردام زندگی می‌کرد این بار به تنهایی و گه‌گاه با همراهی زنان خواننده، با صحنه‌پردازی‌های پر زرق و برق و لباس‌های براق برنامه اجرا می‌کرد.

در سال‌های اخیر او با نام «بانی ام ِ بابی فرل» به تورهای هنری خود ادامه داد.

به گزارش رادیو فردا، مدیر برنامه‌های وی گفت هنوز علت مرگ فارل روشن نیست، با این‌همه فارل در طول ده سال گذشته بارها از مشکلاتی در زمینه سلامت رنج می‌برد.

به‌گفته وی ماموران هتل در پی آن که زنگ بیدارباش به اتاق او بی‌پاسخ مانده بود، به اتاق او رفتند و او را مرده یافتند.

فارل قرار بود روز پنجشنبه برای شرکت در یک برنامه تلویزیونی به رم پرواز کند.

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DAC پیشنهادی

چهارشنبه ۱۵ دی ۱۳۸۹
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لازم شد در مورد انتخاب های سورس دیجیتالم یه توضیحی بدم.

نوشتم بهترین DAC رو Audio Note میدونم که باید اضافه کنم این DAC رو فقط در سیستم مبتنی بر خودش پیشنهاد میکنم یعنی اگر کل سیستم رو Audio Note جمع کردید از این DAC استفاده کنید. البته این یک قانون نیست ولی احتمال گرفتن بهترین پاسخ از این DAC تو سیستم های دیگه و بدون آگاهی از وضعیت اون پایینه.

من قبلا هم نوشتم Audio Note تو میکرو بهترین پاسخ رو داره ولی شرط استفاده اش اینه کل سیستم رو Audio Note بگیرید حتی بلندگوها رو . البته میشه بعدها بلندگو ها رو با تست و تجربه بیشتر تغییر بدید اما من فعلا بلندگویی تو ایران نمیبینم که هم حساسیت بالایی داشته باشه و هم صداش با Audio Note جور دربیاد.

نظر من اینه Audio Note میتونه بهترین صدا رو بهتون بده اما به این شرط که کل سیستم رو Audio Note انتخاب کنید.

نکته دیگری که میخواستم در موردش بنویسم ساختار DAC هاست. ببینید DAC ها از چند بخش تشکیل میشن، یکی بافر ورودی و مدار تصحیح Jitter هست ، یکی بخش پردازش دیجیتال ، دیگری بخش تبدیل دیجیتال به آنالوگ و در انتها هم فیلتر آنالوگ خروجی.

Weiss و Playback Design بین DAC ها تصحیح Jitter خیلی خوبی دارند و مثلا Weiss حتی تو فرکانسهای پایین هم Jitter کمی داره و هر دو تو این شاخص وضعیت خوبی دارند البته بقیه DAC ها هم تونستند تو این شاخص پاسخ خیلی خوبی داشته باشند و کلا بیشتر سورس های دیجیتال مطرح دنیا Jitter خیلی کمی دارند.

تو قسمت پردازش دیجیتال دو تا ایده هست ، یکی NOS ها (Non-Oversampling) مثل Zanden و Audio Note و 47Lab که این DAC ها روی سیگنال دیجیتال هیچ پردازش دیجیتالی انجام نمیدن و هیچ Upsample و یا Oversample ای ندارند و دیگری اونهایی که پردازش دیجیتال دارند. مقاله 47 Labs رو در این مورد بخونید جالبه :

http://www.sakurasystems.com/articles/Kusunoki.html

We can control the “diffusion of sound coherence” only by constructing it with smaller number of taps. From that aspect, Wadia’s decoding computer (13 taps) or Luxman’s former fluency DAC, DA-07 (3 taps) are considered to be excellent machines. They both received (Wadia still does) outstanding appraisals at the time for their sensual representation of the sound. The sound of non-oversampling DAC is on the extension of these machines, and theoretically, it can exceed those achievements.
The difference between the non-oversampling DAC and the conventional DAC with the digital filter lies whether you attach importance on the accuracy in the time domain or in the frequency domain. In other words, whether you choose the musical performance or the quality of a sound. This trade-off line defines the boundary of the current digital audio format .
A natural, stress-free sound that communicates the musicians’ intention directly to you. That is the sound of non-oversampling DAC. The feel of this sound is closer to that of analog reproduction.

بین اونهایی که پردازش دیجیتال دارند عده ای مثل Lavry معتقدند نباید بیشتر از 2X ما ارتقا فرکانسی داشته باشیم و عده ای هم اینطور فکر نمیکنند. Lavry که مورد تایید رومی هست مقاله های جالبی رو اینجا نوشته که میتونید بخونید :

http://www.lavryengineering.com/supportpage.html

http://www.lavryengineering.com/documents/Sampling_Theory.pdf

Dan Lavry توضیح میده بهترین حالت هم برای حذف نویز فرکانسهای بالا و هم فیلتر مناسب خروجی آنالوگ استفاده از Upsampling 2X هست یعنی از 44.1 کیلو هرتز به 88.2 کیلو هرتز. ایشون توضیح میدن ما همیشه یک trade off بین سرعت پاسخ و دقت پاسخ یک سیستم داریم و نمیشه هر دو رو با هم بیشتر کنیم.

There is an inescapable tradeoff between faster sampling on one hand and a loss of accuracy, increased data size and much additional processing requirement on the other hand.
AD converter designers can not generate 20 bits at MHz speeds, yet they often utilize a circuit yielding a few bits at MHz speeds as a step towards making many bits at lower speeds.
The compromise between speed and accuracy is a permanent engineering and scientific reality.
Sampling audio signals at 192KHz is about 3 times faster than the optimal rate.
It compromises the accuracy which ends up as audio distortions.
While there is no up side to operation at excessive speeds, there are further disadvantages:
1. The increased speed causes larger amount of data (impacting data storage and data transmission speed requirements).
2. Operating at 192KHz causes a very significant increase in the required processing power, resulting in very costly gear and/or further compromise in audio quality.
The optimal sample rate should be largely based on the required signal bandwidth. Audio industry salesman have been promoting faster than optimal rates. The promotion of such ideas
is based on the fallacy that faster rates yield more accuracy and/or more detail. Weather motivated by profit or ignorance, the promoters, leading the industry in the wrong direction, are
stating the opposite of what is true.

تو بحث پردازش دیجیتال ایده های دیگری هم هست مثل استفاده از فیلترهای پیچیده FIR و پردازش های زیادتر و خلاصه تو این پردازش ها برندهایی مثل Wadia و Ayre و Emm Labs و Playback Design و Meridian (فکر کنم Spectral هم تو مدل 4000 تو همین گروه قرار بگیره) تو Time Domain پاسخ بهتری دارند که بنظر من بهترینشون Playback Design هست و عده ای هم مثل Esoteric و Krell و Accuphase و dCS و APL و Burmester ، Gryphon و … تو Frequency Domain پاسخ بهتری دارند که بنظر من بهترینشون Weiss Medea هست.

DAC شرکت Abbingdon Music Research (این برند هم تو رنج قیمتیش خیلی عالیه) هم گزینه های متفاوتی رو برای Upsample به کاربر میده که جالبه. برخی هم از ماژول Anagram استفاده میکنند مثل Audio Aero و ویتوس و Orpheus Lab .

بخش دیگه و مهم یک DAC بخش مبدل دیجیتال به آنالوگ هست که تو این بخش روشهای متفاوتی وجود داره. تو این بخش Weiss و Playback خیلی ایده خاص یا متفاوتی از دیگران تو پیاده سازی ندارند اما تو سایت رومی خوندم Lavry بشکلی درست از Multibit استفاده میکنه. APL و Esoteric و Accuphase میان از موازی کردن چند DAC استفاده میکنند تا پاسخ بهتری بگیرند. dCS به گفته خودش از Ring DAC استفاده میکنه و خلاصه تو این بخش هم هر کدوم ایده ای دارند ولی همشون مجبورند از همین چیپ هایی که کمپانی هایی مثل Analog Device میسازند استفاده کنند، البته Emm Labs ادعا میکنه خودش بصورت Discreet اومده مبدل رو پیاده سازی کرده که جالبه اما من برند دیگری رو نمیشناسم که از همین چیپ های تو بازار استفاده نکرده باشه.

برندهای Zanden و AMR از چیپ معروف Philips TDA1541A استفاده میکنند که بنظر میرسه پاسخ خوبی داشته باشه. APL و Gryphon و بعضی مدلهای Esoteric از چیپ های AKM استفاده میکنند.

تو قسمت فیلتر خروجی آنالوگ و بافر خروجی هم Weiss از مدارات مجتمع استفاده میکنه و برخی از لامپ استفاده میکنند مثل APL و برخی هم از Opamp و برخی هم بجای opamp از مدارات Discreet استفاده میکنند. دک Audio Note از هیچ فیلتر آنالوگ و دیجیتالی استفاده نمیکنه و فقط با لامپ و ترانس خروجی میده.

نکته آخری که هست اینه که ما فراموش میکنیم این سی دی های موسیقی قبلا تو استودیو روشون پردازشهای زیادی شده و ممکنه حتی با یک DAC خوب ما صدای جالبی از اون آلبوم نگیریم و ممکنه با یک DAC غیر ایده ال تر با همون آلبوم پاسخ بهتری بگیریم.

غیر از سورس هایی که معرفی کردم پیشنهاد میکنم روی Lavry و Bow Technologies هم تحقیق کنید.

زیباترین DAC ای که دیدم هم Orpheus Labs سوئیسی بود که عکسش رو اون بالا گذاشتم.

تا این لحظه سیستم های پیشنهادی من به شرح زیر بوده :

بلندگو :    Marten Design ، Tidal برای صداهای Live و ESP برای صدای حسی که هر سه بلندگو حساسیتی زیر 94 دی بی دارند

آمپلی فایر :  ASR Emitter برای توان های بالای 100 وات و Vitus برای توان های زیر 100 وات ، هر دو آمپلی فایر مناسب برای بلندگوهای با حساسیت زیر 94 دی بی و Audio Note UK برای زیر 50 وات مناسب با بلندگوهای بالای 94 دی بی حساسیت

مبدل دیجیتال به آنالوگ : Audio Note UK برای صدای حسی و Playback Design و Weiss برای صداهای Real

کابل : برند Jorma Design برای حالت عمومی و Van den Hul تمام کربنی (برای شرایط خاص)

بقیه برندهایی که معرفی شدند مثل Concert Fidelity و یا Decware هم تو گروه بهترین کیفیت با توجه به کمترین قیمت بودند (بقول خارجی ها Best Performance/Price).

باید برای بالای 94 دی بی حساسیت هم بلندگو معرفی کنم و همچنین برای ترنسپورت و سورس آنالوگ.

تا یادم نرفته سایت زیر رو ببینید، اخبار رو مینویسه :

http://cybwiz.blogspot.com/

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DAC پیشنهادی من

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اگه یادتون باشه قرار بود سورس دیجیتال معرفی کنم و من فعلا بدون معرفی Transport میرم سراغ DAC پیشنهادیم.

همونطور که قبلا گفتم من دو دسته رو در نظر میگیرم یکی صدای Real و دیگری صدای Emotional که اولی تو ماکرو پاسخ بهتری داره و دومی تو میکرو.

تو گروه DAC ها اونایی که پردازش دیجیتال ندارند مثل DAC شرکت Audio Note UK و یا DAC شرکت Zanden صداشون بیشتر Emotional هست که با چیزهایی که من دستگیرم شد DAC شرکت Audio Note میتونه بهترین انتخاب باشه البته Zanden هم خیلی خوبه اما من در مجموع فکر میکنم اگر یک Transport خوب رو به Audio Note بزنیم صدایی فوق العاده خواهد داشت.

پس تو پاسخ میکرو انتخاب من Audio Note UK هست که تو ایران هم نمایندگی داره (آقای فاطمی).

اونایی که پردازش دیجیتال دارند صدایی Clean تر و در ماکرو بهتر دارند که بین همه اونها من DAC شرکت Weiss رو پیشنهاد میکنم.

البته ما دو گروه تو پردازش دیجیتال داریم، یکی اونایی که تو Time Domain پاسخ بهتری دارند و یکی اونهایی که تو Frequency Domain پاسخ بهتری دارند. DAC شرکت Weiss بنام Medea تو Frequency Domain بهترین پاسخ رو داره و DAC شرکت Playback Design تو Time Domain .

خب نتیجه اینکه تو صداهای Real من دو گزینه رو پیشنهاد میکنم :

Weiss Medea

Playback Design

خودم به دومی گرایش بیشتری دارم تا به Weiss اما طراحی Weiss هم طوریه که صداش واقعا Impressive هست و انتخاب بین ایندو تا حد زیادی به بقیه اجزای سیستم وابسته هست.

اینم ترتیب اولویت های من تو انتخاب سورس دیجیتال :

1. Audio Note UK DAC5 , DAC4 (عکس بالا)

2. Playback Design MPD-5 , MPS-5

3. Weiss Medea

بد نیست بدونید رومی DAC شرکت bidat و Lavry رو دوست داره.

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Vitus Audio with Wilson Sasha in CES 2011

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عکس بالا آقای ویتوس و همسرشون در کنار آقای ویلسون و همسرشون تو نمایشگاه CES 2011 در امریکا

ویتوس تو جواب ایمیل تبریک سال نو بهم گفت تو غرفه شون تو نمایشگاه CES 2011 ویتوس رو با ویلسون ساشا دمو کرده.

منم به آقای رحمانی اس ام اس زدم گفتم آقای رحمانی کارتون درسته شما اینجا ساشا دمو کردید اون ور دنیا ویتوس هم تو نمایشگاه از ساشا استفاده کرده 😉

منم امروز نمیدونم چرا الکی خوشحالم

خوش باشید

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Color Theory 101 by jessie.dazzle

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مطلبی رو تو انجمن رومی (http://www.goodsoundclub.com/) دیدم که جالب دیدم اینجا بیارمش، موضوع اینه که رومی و برخی معتقدند ما نباید دنبال این موضوع باشیم که یک سیستم صوتی دقیقا کل اطلاعات یک اجرای زنده رو بازسازی کنه بلکه باید فرض کنیم هر صدایی یک چیز جدید هست که با اون صدا به عنوان یک هویت مستقل و جدید برخورد کنیم.

قبلا هم من به این موضوع پرداختم و اگه یادتون باشه نوشتم صدای بازسازی شده رو میشه به کشیدن عکس مربوط کرد که نوشتم یک کاریکاتور خوب خیلی بهتر تو ذهن بازسازی میشه تا یک کپی غیر خوب.

این موضوع خیلی موضوع مهمی هست و بنظر من جای تامل داره چون خیلی ها بخاطر Impression دقت صدای یک سیستم مثل FM Acoustics (و یا پاسخ دامنه Flat بلندگویی مثل Dynaudio و دیستورشن کم آمپلی فایری مثل Goldmund) فکر میکنند چون این صدا صدای خیلی Live ای هست پس باید به این سمت حرکت کنند و رومی هم معتقده بیشتر مهندسان صدا که همش تو ذهنشون صدای یک سیستم رو با صدای اجرای زنده مقایسه میکنند نمیتونند مسیر رو درست انتخاب کنند.

تو این لینک چند نفر هم نظرات جالبی دادند حتما بخونید:

http://www.goodsoundclub.com/Forums/ShowPost.aspx?postID=3400

Color Theory 101

The following reflects the current state of my understanding, and in some cases, my opinion… I welcome and very much value other points of view.

Max, regarding B&W and Color : Actually we do agree here ; I did not write (nor mean to suggest) that one could replace the other. They most certainly cannot substitute each other.

Paul, please bear with me ; this does get back to audio.

When you view a B&W film, your eyes register contrast. This contrast renders the scene legible without color. However, a color film without contrast would be illegible.

A person with totally defective cones (color receptors) is totally colorblind. A person with totally defective rods (contrast receptors) is just plain blind, and no amount of perfect cones will change that.

Without contrast, color is of no interest.

It is contrast not color which defines space.

In the first image, all the color information was removed, but all the contrast was preserved.

In the second image, all the contrast information was removed, but all the color was preserved (meaning that all color was brought to the same level of contrast… You can see how little color info this image really has)

Whether you view a film, or listen to music, your mind is actually reading space (I am not referring to the recording space) ; The writer or composer sets up immagery through which your mind navigates. It does not matter whether you see the input or hear it or both, you mind is on the move.

Contrast, is fundamental to the perception of this space or any other space.

Color is fundamental to the perception of… color. It is an additional but subordinate level of information.

Yes space can have color, and yes color can help or hinder the definition of space.

The term relative contrast (as opposed to absolute contrast) refers to the contrast within a scale defined by a given situation. Your mind auto-calibrates to these scales.

My point in the example of the black and white film is that even though life happens in “Living Color”, the mind calibrates to this limited set of information, and in the case of a good film, the mind recognizing it has what it needs, takes that information, and runs with it.

How does that translate to audio ?

A musical performance may contain many times more information than the creator intended to convey.

Again, this is my opinion :

It is not necessary or even desirable that a system reproduce all the information of the live event.

Yes some of this information is of interest, but this is not the meat of what allows perception.

The principal element of what allows perception of sound can only be put forth in terms of relative contrast.

Relative contrast of duration, pitch, dynamics, and timbre.

It is difficult enough to assemble a system that completely renders all information the performer intended to convey in just these terms.

Just as in a painting, until relative contrast is mastered, the addition of color serves only to further pollute the message.

What I’m saying may sound obvious, but consider how many expensive systems you’ve heard that are capable of rendering micro-detail, without completely nailing the basics.

The typical list is as follows :

The compromised Mid Range driver being solicited for Mid Bass duty as well

The total absence of real Mid Bass / Mid Bass with tone

The overly hot, overly present High Frequency driver

The Lower Bass which has no tone and is way too strong around 40Hz because the ports have to kick in somewhere…

With problems of this magnitude, the rendering of a finer level of detail is as ridiculous as dressing a pig in a Chanel gown.

************

Regarding the possibility to replicate a live performance via HiFi :

The musician uses his musical instrument to produce sound. The musician does not try to get the sound of a cello from his instrument unless it is a cello (or a synthesyzer). The HiFi guy on the other hand uses the one membrane of his Mid Range driver to produce the sounds of half the instruments in an orchestra, sometimes all playing at once !

It is said that “a good driver can handle the simultaneous reproduction of more than one sound”… Hold that thought, I’ll get back to it.

When you think what a Mid Range driver is being asked to do in the case of an orchestral performance, even the crappiest of drivers is at first glance performing what seems to be a miracle ; something way beyond what the technology involved would suggest. How can a piston moving in two dimensions start, stop, and change direction fast enough to produce the sound of all those instruments playing at once?

The answer is simple, and it is not a miracle ; This is possible only because the human ear is also a one membrane system, in a way, a mirror of that one driver.

When we listen to live performances, the membrane of our ear is being pressured by the natural sum of several sounds. From this, our brain re-assembles a sound image.

The fact that to our ear, a driver can mimic the symultanious reproduciton of more than one sound, does not mean that it is producing several sounds. It is producing the sum of several sounds, first summed by the microphone(s) and all the recording gear, and then sent as a summed package via all our play back gear to act on the drivers membrane, finally pressurizing the membrane of our ears. The difference : In the case of a live performance, our ear is allowed to sum the input, and our brain processes this raw information directly ; In the case of HiFi, the summing has already been done, and our brane is asked to extrapolate a line of pre-summed information.

To hope to reconstruct the original picture from information that has been completely altered (in different ways with each recording) seems ridiculous.

For this reason, if one day somebody does succeed in reproducing the sound of a live performance via HiFi, I would not be surprised to see they started by creating a recording consisting of several channels, each one carrying the information from only one instrument. This multi-channel recording would then be played back via a corresponding number of dedicated drivers set up where the instruments were found (relative to each other) at the time of the original event, leaving it to our ears and minds to sum and decode the total.

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ESP Speaker Concert Fidelity Amplifier , Steve Hoffman Report

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استو هافمن رو میشناسید یکی از مهندسان صدا و آئودیوفیل های درست حسابیه که نظراتش به من نزدیکه.

http://www.stevehoffman.tv/dhinterviews/

ایشون نظرشون رو در مورد بلندگوی ESP و آمپلی فایر Concert Fidelity نوشتند که جالبه. من حدس میزنم با این وضعیت ای که بازار داره احتمالا برند ESP هم مثل برندهای بسیار خوب دیگری چون Hovland و Lyra از دور خارج بشه و دیگه محصول تولید نکنه. امیدوارم ESP قبل از تعطیل شدن به ایران بیاد.

http://www.stevehoffman.tv/forums/archive/index.php/t-83750.html

Steve Hoffman
06-16-2006, 07:40 PM
I’m lucky. Because of the work I do I get offered free stereo gear all the time from kindly manufacturers who want me to endorse their products. I’m always willing to try something out but usually it goes right back. I’m pretty picky. I rediscovered ESP speakers in a different way. Back in the ancient ’90’s a friend who was the insurance rep for DCC Compact Classics had me over to his house to check out his new stereo which consisted of a Sony CD player, a VAC Renaissance 30/30 power amp and a pair of medium sized speakers by the name of ESP. I remember thinking at the time that the amp/speaker duo made a very pleasing sound, quite unlike the “in your face” razzle dazzle of most upscale audio gear being produced around that time. I filed that factoid in my brain. A few years ago I was giving a lecture at the Rocky Mtn. Audio Show in Denver and I wanted to check my music disc to see if it would play correctly. Noticing that there was an ESP room at the show I remembered the nice sound at Mark’s house and just walked in the room and asked to use the system for a few minutes. Well, the ESP Bodhrans were in there and the Concert Fidelity electronics and I remember sitting there and thinking that this was a sound that I could listen to for hours at a time without getting my ears burned off. Now I have almost the exact system in my house courtesy of ESP and Concert Fidelity. Like I said, I’m lucky.

I want give you a few thoughts on ESP Speakers.

I wrote earlier about how the combination of my ESP Bodhran SE speakers and Concert Fidelity electronics have given me uncommon musical pleasure along with the subtle kind of harmonic, timbral and dynamic nuance I need to hear in my mastering work. (See article here….):

http://www.stevehoffman.tv/forums/showthread.php?t=83356

To get both of these at the same time is much rarer than most people think, so I’d to talk a little about it here, focusing on the ESP speakers. But first, I need to define “musicality,” a word which is so often misused but which definitely defines ESP.

Words are tossed around in audio circles all the time without rigorous definitions. To a lot of over-analytic audiophiles, “musicality” can be a bad word, implying smoothing-over details in order to make a component easy to listen to. To others, “musicality” is totally subjective–whatever they like is termed “musical,” no matter how “hi-fi” it sounds. When I say a component is musical, I mean it manages to sound organically whole and seamless and has the ability to move air and convey emotion WITHOUT sacrificing the nuances of detail, harmonics, timing, and microdynamics; all essential for “lifelike reproduction of sound” (to use a J. Gordon Holt phrase). Friends, getting all of this right AT ONE TIME is a rare feat—many “hi-fi” components err on the side of an overly analytic presentation which dissects the music and loses that needed wholeness. Still other components err on the side of lush and smooth, lacking the nuance necessary to be ultimately satisfying—but it’s a feat the ESP’s perform, and especially in combination with world-class electronics like the Concert Fidelity stuff.

I have heard Sean McCaughan’s (the designer of ESP) creations and met him on numerous occasions, both at the CES, Stereophile Show and at my house and he is a great guy who knows what he likes in the way of reproduced sound. I can definitely say that he is a different kind of speaker designer. I would almost describe him more as a design artist than as a technologist. Although he’s obviously knowledgeable and experienced in speaker design (dating back almost 30 years to when he designed on the Beveridge electrostatic team), he is a modest man who would much rather talk about MUSIC than about technology. He goes to a lot of concerts, and his focus is on building products that are timeless and intensely musical, rather than on writing white papers hyping the latest technology. I think his results really speak for themselves: A very palpable, spacious, dimensional, seamless, NATURAL sound, but with unlimited macrodynamics so the speakers can get up and rock if they have to (if you have the juice).

His speakers incorporate some design features which are very different from today’s trends in speakers and they may be hard for some audiophiles to understand at first, since so many people are attracted to speakers that jump out and grab you immediately with tipped-up highs or bone-crunching bass, even if that’s not what real music sounds like. Sean always like to say that ESP’s are not technically “audiophile” speakers—they’re not pyrotechnic enough for many listeners and it’s true that ESP’s may not stand out at shows because there are just too many bright “hi-fi” systems all around to condition showgoers’ ears in the wrong way. Oftentimes, the people you’ll see hanging around the ESP room at shows are musicians and other true music lovers who know what music is supposed to sound like, not audio nerds or gearheads who are looking to hear this or that sonic artifact in a short sound-byte. Not that his speakers are an acquired taste, let me just say that you have to listen for more than a few minutes to let your ears get reaccustomed to a natural sound palate. I always hang out in the ESP room at a stereo show when I want to decompress from the wacky and go back to the lifelike. 🙂 After 10 minutes with the ESP’s, I’m calm again.

Let me list several of the unusual things Sean does to achieve the sound he wants. Oh, by the way, these speakers really could be called labors of love by Sean, if they weren’t so time-consuming and backbreaking to build! A pair of Bodhran SE’s takes two weeks from start to finish, and a pair of Concert Grand SI’s takes longer! This is a true pain in the *** and only someone totally committed to getting an exact sound could do it.

First, Sean angles the front baffles in by forty-five degrees, causing the on-axis sound from the two speakers to cross several feet in front of the listener. This leads to a very wide listening position, the first criterion for a speaker designed for natural music reproduction. No head-in-a-vise stuff here, but amazingly, the imaging is still solid and very dimensional.

Another thing Sean does to achieve extra spaciousness is use aperiodically damped venting to release out-of-phase sound from the woofers and midrange out of the sides of the speakers. There is also a side-firing tweeter which is down in level and out of phase. This design feature makes the speakers almost like dipoles. They throw an unusually wide and deep soundstage, but without sacrificing the important solidity of the central image. In fact, their image solidity and dimensionality is rather unique and actually much better than what you get from most audiophile speakers. Sean says he is asked all time at shows if his speakers are electrostatics! Cracks him up.

A third thing he does is use SEALED-BOX DESIGNS. The aperiodically damped venting is not the same as ports, and you will not hear any “boom” from Sean’s speakers. If the speakers are properly set up (and preferably spiked into concrete like mine are) you will hear very extended bass, but it is not the kind of port-induced artificial boom or slam that so many speakers resort to in order to get bass out of small cabinets. Yes, ESP’s are somewhat large for their frequency response. Sean designs speakers the old-fashioned way, with no gimmicks, but with the creative design touches mentioned above.

The irony in all this is that ESP DO deliver all the craved-for audiophile goods like detail resolution and imaging and soundstaging—again, they’re absolute kings in terms of imaging and soundstaging—but in such a natural way that they don’t jump out and hit you over the bean. Anyone who thinks “musical” means sacrificing detail should hear what I’ve heard when I’ve switched electronics or cables or even vacuum tubes. In fact, I hear these changes even MORE on the ESP’s than on most speakers, and it’s really quite amazing to me how they can be so musically enjoyable and yet so resolving at the same time. That is true design art, and in my opinion, unique.

The other night, Sean, Mike Verretto (US distributor) and I had a truly magical experience listening to some Frankie Sinatra on my ESP/Concert Fidelity system (a rare system in that I can use it for both mastering and listening). There was an extremely realistic and palpable presence to the sound, especially in the midrange, which put Frank scarily close to being in the room, even on this 1953 monaural recording. I even heard a french horn part that I hadn’t heard before on other systems. With my current ESP/CF system, I’m getting a lot more of that magic these days, and I’m too jaded to say that lightly. What is so addictive about the midrange is that it is very rich and tonally natural but also highly resolving, as long as the electronics are up to the job. On too many speakers, that palpability in the midrange seems to get lost in the quest to make the lows and highs stand out so that the speakers are more “impressive” and easier to sell. But even with their magical midrange, the ESP’s don’t sound bloated or chesty, which would happen if a less talented or sensitive designer tried to emphasize the midrange.

One quirky thing about these speakers is that they do take some skill in setup. Because of their additional side-firing output, they are VERY sensitive to room placement but they do respond to minute care in placement as all great speakers should. Of course, friends and neighbors, I’m lucky to have had Sean himself visit my place to set them up properly, and when that setup is done right, the speakers completely disappear, which you would not expect from their large size. This allows them to sound equally as convincing on intimate jazz or chamber music as on Bad Company, Van Morrison or a giant orchestra playing something by Leroy Anderson (check out the great SACD on Mercury Living Presense).

Like all good things in life, these speakers are not inexpensive ($16K for the Bodhran SE’s, which I have now, and $40K for their bigger brothers, the Concert Grand SI’s), but they are hand-built artisan products in which the designer himself is actively involved at every stage of design and production. They are speakers to last your lifetime (my insurance buddy still has his and he LOVES to change gear every few years) and worth the money. Heck, if you bought a Honda Civic you would spend 20 grand and have nothing in 6 years. Your ESP’s on the other hand will still be going strong in 20.

OK, blathering over, time to summarize:

Speaker choice is highly personal, since speakers always have more “character” than electronics. But if you are looking for the same things I am: an organic, seamless, spacious, dynamic presentation, with lots of natural detail rather than the hyped-up “audiophile” kind; and especially, if you’re really interested in music rather than just sounds, go hear these beautiful babies!

http://esploudspeakersna.com/welcome/index.html

Here is a shot of ESP designer Sean McCaughan’ and I at CES with the larger ESP speakers. Note the pretty burled maple wood. I have the maple Bodhrans in my living room; very good WAF (Wife Acceptance Factor).

تو بخش دیگری اینطور نوشتند :

Friends, for the last couple of months, and especially since the Stereophile show, I’ve had much more chance to listen to the ESP/Concert Fidelity system that is in my main listening room and I’ve decided to write down some more thoughts. I’m convinced that this system is perfect for the serious audiophile and music lover. The ESP Bodhran SE monitors and the Concert Fidelity 6BFG monoblock amplifiers and matching CF-040 tubed line stage are getting quite a workout at my place and constantly furnishing me with great sound. My thoughts on the ESP loudspeakers I will post in a separate thread. I want to elaborate on the Japanese Concert Fidelity electronics here. Allow me to gush for a few minutes.

The system I’m using now is the first I’ve had that both allows me to master accurately AND makes me want to sit down and listen to music even after a long day of mastering. Even when I listen for relaxation, I expect to be able to hear all the details and nuances I’m so used to hearing on the master tape, but in a natural, organic, totally non-fatiguing sort of way. Most systems err either on the side of being overly analytic without naturalness and organic “wholeness”, or on the side of rich and lush while missing the nuances I try to bring out in my mastering. My current system, even in a less-than-optimal setup (with a big old grand piano between and behind the speakers), is a true miracle of great sound. It’s so lifelike and yet so un-“hi-fi” that I’ve heard things on the mixes that I’ve never noticed before, and yet without ever sacrificing crucial musicality. With this system, I’ve come as close to the sound of the master tapes as I ever have before. Sinatra and Elvis were scarily close to being in the room with us the other night, and I don’t say that lightly.

Concert Fidelity Electronics
http://www.audiocriticalmass.com/

Some people like tube sound, some like solid state. But I feel the perfect electronics should combine the best of both worlds—the transient speed and transparency (and bass) of solid state without the grain; the timbral magic and dimensionality of tubes without mushy bass and rolled off highs and lack of focus. For example, pairing the Concert Fidelity original prototype electronics with the Venture CR-8 speakers in my mastering room, I’m now getting the best bass I’ve ever heard in that room in eight years of living here. Because of their incredible midrange magic, the Concert Fidelity electronics remind me of just why I’ve always loved tubes, but they also point out clearly how not all tube electronics are even close to being equal. The Concert Fidelity stuff has a clarity (presumably because of their highly simplified but wacky perfectionist circuitry) which allows me to hear much more of the microdynamic and harmonic nuances and transient speed that other tube electronics simply miss or gloss over or just choose to ignore, and this becomes addictive and necessary for testing my mastering work, as well as for listening. It’s the kind of magic that most people might not even know existed until they’ve once heard it, but once they have, they realize how much of the nuances are getting lost through other electronics. No going back after this for me. I’m too spoiled; it’s friggin’ addictive, mates.

But first, one minor caveat: Those of you (anyone out there?) who heard the Concert Fidelity stuff at the Stereophile show on either Thursday or the first half of Friday missed the magic, because the line-stage was not hooked up properly (i.e., the 12AU7’s were not switched into the circuit). This kind of silly thing can happen when people are exhausted from doing all-nighters getting ready for a show and then setting up the show room… We all knew something was not right, but we were too blitzed to figure out what it was! After Friday around 1PM, the electronics were back to sounding the way they are supposed to. All it took was turning the second switch to “on”, heh.

This line-stage is, quite simply, the most transparent I’ve used, and I’ve had some great line-stages through here, some true Kings. Every time I do a comparison (and I wouldn’t waste my time comparing it with less-than-excellent line-stages—so far, I’ve put it up against a number of the very best, but please, don’t ask me for names!), the Concert Fidelity wins easily in terms of lifelike sound, dynamics, sound-staging, side-to-side imaging, tonality, and all-around pleasing vibe. It also has one other huge advantage. Because of its neat transparency, it is almost like a tube tester in the way it shows off the differences between 12AU7’s. This allows me to flavor the final sound by tube rolling, that final touch that means so much. I’ve spent silly time rating all of my 12AU7’s. Couldn’t do it without the C.F. line stage!

And I hear it will soon get even better than this, although it’s almost hard to believe it could! Masataka Tsuda, the designer of the electronics, will soon be coming out with his ultimate statement line-stage, which incorporates four or five minor circuit changes in addition to remote control and digital volume readout, two things which the current minimalist line-stage is, unfortunately, lacking. I have been told by the importer that in order to sell off the remaining few current units, which ARE FULLY UPGRADEABLE to the ultimate line-stage, a price break is being offered. (Since the cost of the upgrade is expensive and there is no margin in it for dealers, the current inventory cannot be sent back for upgrades first and then resold to dealers at wholesale—it has to be sold to customers first.) If you are looking for a line stage that will please you for a life time. Consider this one, folks.

So there ya have it. Steve’s gushing. The Concert Fidelity electronics are expensive as hell, but there are more expensive products out there, especially from Japan, where most things are perfectionist and expensive. And every time I turn those Concert Fidelity amps on I wonder if we have come as far as we can in vacuum tube reproduction of recorded sound. They are that good. They remove the barrier between me and the music. As I said before, I doubt there would be a listener anywhere on the planet who would not love the sound of those gorgeous, monoblock amplifiers and that nifty magical line-stage. I can recommend them with total confidence to anyone who strives for the best sound possible. This is the kind of product that will make people stop agonizing about upgrades once and for all. If they have deep enough pockets to buy this stuff, they’ll be able to forget about “moving up” and will be able to listen to music under the best conditions possible for a very long time to come. Even though I’m assured of a long-term loan of this gear for my mastering projects, just the thought of losing it gets me all shivery. Not looking forward to that day; I’m spoiled, dudes!

The Concert Fidelity stuff has only been available since last fall in its current cosmetic shape (with wonderful lacquered wood), and although the company may be obscure now, don’t expect it to be for much longer. Also, for those of you who just don’t want tubes, Masataka Tsuda’s new solid state creations, under the “Silicon Arts Design” brand, are now in prototype. Several very critical listeners who heard them during special after-hours auditions at the Stereophile show have already proclaimed them the best amps they’ve ever heard. And they are solid state! Might have to give those a serious listen. Given Tsuda-san’s profound design expertise and fanatically perfectionist tendencies, that doesn’t surprise me at all. (You’ve got be slightly wacky to design stuff anyway, and Tsuda-san is just as wacky as the American designers I’ve met; this is a good thing!)

Although I’ve posted pictures before, it’s worth taking another look at several of the features of these electronics. In the line-stage, notice how SIMPLE the circuitry is, how well laid-out and clean looking it is, and how close much of it is to the input and output connectors, for shortest circuit paths. The new ultimate line-stage will extend this concept to its logical extreme, while having the 12AU7’s swappable on the back panel so the unit doesn’t have to be opened up.

In the power amps, notice how the single 6SN7 for the driver and gain stages is BEHIND the transformers in order to shorten circuit paths and eliminate stray capacitance that leads to the dreaded dulled transients. Notice some other nice touches, such as an input level control for channel matching as tubes drift over time, and a digital output tube timer/counter so you’ll know how long you have been running the output tubes and when you should replace them. And those transformers are custom-spec’ed and very expensive, practically unobtanium, but contribute greatly, along with the circuitry and layout, to the sound which has the best aspects of tubes without the downsides. Oh, and Tsuda-san chose the CURRENT PRODUCTION Russian 6B4G, a very tuneful tube (sort of like the sound of an old 2A3) so there is no fear of running out of output tubes in the future. I must say that in both sets of my Concert Fidelity amps I’ve never had A SINGLE TUBE PROBLEM! Not a one.

At any rate, that’s my story and I’m sticking to it. If you can afford them, the Concert Fidelity electronics will satisfy you for many years. There will be no need to ever worry about “the search” for the best sounding gear again!

راستش چند وقته پیش تو خواب دیدم یک سیب بزرگ محکم خورد تو سرم و من تو خواب بخشی از عقلم رو از دست دادم و رفتم یک سیستم صوتی جدید مبتنی بر ESP ، Vitus و سورس Playback Design خریدم.

بیدار که شدم دیدم خوشبختانه عقلم سرجاشه و خوشحال شدم از اینکه دیدم بیرون دهکده هستم.

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برنامه های فای از شبکه چهار

شنبه ۱۱ دی ۱۳۸۹
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خبر جدید اینکه به احتمال زیاد برای اولین بار در ایران یک برنامه تلویزیونی در زمینه های فای بزودی از شبکه چهار پخش خواهد شد.

قرار شد همین هفته با شبکه چهار مذاکراتی داشته باشم و در اولین فرصت نتیجه رو اعلام خواهم کرد.

تمام سعی ام این خواهد بود تو این برنامه تلویزیونی مخاطبان رو به شکلی ساده با های فای آشنا کنم و این فضا رو به تمام کسانی که شناختی از های فای ندارند معرفی کنم.

مطمئنا این موضوع هم برای مخاطبان شبکه چهار جالب خواهد بود و هم برای فضای های فای ایران چرا که بنظر من تا حد زیادی این مقوله برای مردم ناشناخته هست.

شاید اتفاقات خوبی بیفته …

فقط برای های فای مجری گری نکرده بودیم که اونم داره انجام میشه 😉

خوش باشید

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تاثیر فیلتر دیجیتال بر پاسخ فاز خروجی آنالوگ یک سورس دیجیتال

چهارشنبه ۸ دی ۱۳۸۹
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Comments Closed

مقاله زیر رو طراح Ayre نوشته که بنظرم خیلی خوب مطلب رو توضیح داده. قبلا هم گفتم برخی طراحان سورس دیجیتال مانند طراحان برندهای Meridian ، EMM Labs ، Spectral ، Playback Design که فیلترهای دیجیتال رو کدنویسی میکنند سعی میکنند کاری کنند پاسخ فاز بهتر بشه و سیگنال تو Time Domain وضعیت بهتری داشته باشه.

بخونید :

https://www.hifi.ir/wp-content/uploads/2010/12/Ayre_MP_White_Paper.pdf

Ayre is pleased to announce the results of an intensive research program into the audible performance of various digital filters (including “non-oversampling” filterless designs). Extensive listening tests have shown that our new custom DSP-based “Minimum Phase” filters provide a significant leap forward in both musical naturalness and ease of listening. All of our current digital products use these filters, and upgrades are also available for all Ayre disc players still in production.

The Evolution of the Digital Filter

To illustrate the performance differences between various digital filters, included are graphs of their two key parameters—their frequency response and their transient (impulse) response. These graphs allow us to trace the evolution of the digital filter,
clearly showing the changes that have led to improved sound quality.
In the beginning, there was the common linear-phase, “brickwall” digital filter. This type of digital filter is used in 99+% of all modern digital equipment, for both recording and playback, including the “Measure” position of the original Ayre disc players.
On paper, it looks nearly perfect. There is no phase shift, so it is called a “Linear Phase” filter. However, a filter can only achieve a “Linear Phase” response by introducing pre-ringing. This means that before every single musical transient, there is a “pre-echo”. In nature, there is no such thing as a “pre-echo”. All events must be “causal” in the real world—the cause must precede the effect.

A sharp, “brickwall” filter like this typically introduces about 20 cycles of pre-ringing and 20 cycles of post-ringing. It is very unnatural sounding, as the effect (pre-echo) precedes the cause (musical transient). This time-smear is interpreted by the ear-brain as both a lack of image precision in the soundstage, and also a subtle smearing of the musical sounds together.

Improving the Transient Response
The first approach to solving the problems of a conventional digital filter was to use a filter with less ringing, often known as a “slow roll-off” filter. This type of filter was used in the “Listen” position of the original Ayre disc players. By reducing the “sharpness” of the “knee” in the filter’s frequency response, the filter’s transient response is vastly improved.
Now there is only about one cycle of pre- and post-ringing. The penalty (remember, there is no such thing as a free lunch—only intelligent tradeoffs) is that there is more “leakage” (aliasing) of high frequencies above 22,050 Hz back in to the audio band. Still, this only affects very high
frequencies and the levels are low enough not to cause audible problems.
This “slow roll-off” filter reduces the time smear by a factor of ~20x compared to conventional digital filters. The net result is a much more musically natural sound, as the ear-brain is very sensitive to time-related distortions. This filter provides an outstanding compromise between frequency response and transient response, and for ten years was the mainstay of Ayre’s digital audio filters.
A natural extension to this idea is to eliminate the digital filter altogether. In theory this provides the best transient response possible from a digital playback system. There are certain audible advantages to this approach, but they are highly system-dependent and come at the expense of two separate problems.
The first is a loss of high frequencies starting at -0.75 dB at 20 kHz and reaching -3.2 dB at 20 kHz. The second is that the aliased “image” frequencies are injected into the audio signal, creating non-harmonically related distortion that increases in level as the frequency increases, reaching over 50% at 20 kHz unless additional analog filtering is employed. Careful listening tests revealed that these drawbacks outweighed the gains in improved transient response, especially given the CD format limitation with its 44.2 kHz sample rate. We therefore continued examining different approaches to digital filtering.

Eliminating the Pre-Echo
In Peter Craven’s 2004 AES paper, he proposed that the playback DAC should include a digital filter that had a corner frequency below the half-sample rate of 22,050 Hz. This would filter out any ringing (pre- and post-) that was introduced during the recording process and thereafter embedded on the disc itself. He named this an “apodizing” filter. It is a mathematical law of any filter, digital or analog, that the steeper the frequency cutoff, the more ringing it will have. In an attempt to avoid the problems of this ringing, Craven proposed using a “Minimum Phase” filter instead of the conventional “Linear Phase” filter. While this means that the phase response now varies, especially at high frequencies, there is no longer any pre-ringing. Furthermore all pre-ringing from the recording process has been filtered out, and the new playback filter only has post-ringing.
Now a giant step forward has been taken in the musical naturalness of digital audio reproduction. The unnatural pre-echoes have been completely eliminated. All of the filter’s ringing occurs after the musical transient. This is just the way that sounds occur in nature. Every sound made in the real world will have post-echoes after the original sound, so the ear-brain system more easily accepts these post-echoes from the digital filter as natural. Note that the post-ringing of a “Minimum Phase” filter is greater than that of a “Linear Phase” filter with the same
frequency response. The energy that had been contained in the pre-ringing of the “Linear Phase” filter has simply been delayed until after the transient. (Remember—there are no free lunches.) But redistributing this same total energy leads to significant gains in musical realism.
This type of digital filter is not available in off-the-shelf chips. Instead, it must be implemented in custom DSP filters. In the case of the new Ayre MP (Minimum Phase) disc players, we use sophisticated FPGAs (Field Programmable Gate Arrays) to create the desired custom filter, and the chip is easily reprogrammable should future improvements be made. This filter type is used in the “Measure” position of the new Ayre MP disc players.

The Best of Both Worlds
While the “Apodizing” filter proposed by Craven solves many of the problems with digital filters, careful listening tests conducted at Ayre showed that the multiple cycles of post-ringing still created an artificial brightness and an overall confusion to the sound. We therefore sought to combine the best aspects of Craven’s minimum-phase digital filter proposal with a slower roll-off that reduced the overall amount of ringing.
The resulting filter has no pre-echoes, and only about one cycle of post-ringing. This filter is implemented in the “Listen” position of the new Ayre MP disc players. The result is simply the most musically natural digital playback available today.
In addition to the radical improvements provided by the digital algorithms themselves, several man-months were spent conducting thorough listening tests to optimize all other aspects of the filters. The powerful customprogrammed FPGAs used in the MP series allow performance far beyond that available from off-the-shelf solutions. The mathematical calculations are conducted with 32-bit coefficients, using 64-bit accumulators to ensure the greatest degree of signal precision.
A 26x oversampling rate was determined to provide the highest level of musical realism. All of the filtering calculations are accomplished in a single pass through an FIR (Finite Impulse Response) filter. This is in contrast to conventional designs that employ a cascade of 2x FIR filters, thereby losing critical precision of the audio data as it is passed to each successive filter section. Finally, the dither algorithms for both the “Listen” and “Measure” filters were chosen on the basis of careful listening tests to provide the most realistic music reproduction possible.
The Ayre MP filter provides a significant step ahead in digital audio reproduction. The CX-7e provides this advanced technology for CDs, while the C-5xe universal disc player takes this to the limit of today’s recording technology at 292 kHz and 24 bits. In addition, this exclusive advance in digital audio reproduction is included in the Ayre QB-9 USB DAC, achieving the most natural and realistic sound available from computer-based audio systems.

http://www.stevehoffman.tv/forums/archive/index.php/t-186820.html

http://www.stereophile.com/content/meridian-8082808i2-signature-reference-cd-playerpreamplifier-measurements

http://www.stereophile.com/features/106ringing/index.html

http://hifiduino.blogspot.com/2009/05/wm8741-digital-filters.html

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پنل های آکوستیکی Vicostic توسط شرکت فراصوت نگار

دوشنبه ۶ دی ۱۳۸۹
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Comments Closed

شرکت فراصوت نگار به آدرس (http://www.farasoutnegar.com) وارد کننده پنل های آکوستیکی Vicostic میباشد.

برای دانلود عکس بالا با وضوح زیاد بر روی لینک زیر کلیک نمایید:

http://www.vicoustic.com/vicousticnovo/imagensextra/catpg2.jpg

این خبر رو دوست خوبی برام ایمیل کرد که برام جالب بود، مثل اینکه قیمت هاشون هم مناسبه و طرح و شکل پنل ها هم زیباست.

این شرکت برندهای دیگری رو هم در زمینه تجهیزات استودیویی وارد میکنه که میتونید تو سایتشون ببینید.

امیدوارم دوستداران های فای در ایران علاقه بیشتری به تغییر شرایط آکوستیکی نشون بدهند و این برند با فروش و استقبال خوبی مواجه بشه.

آدرس و تلفن شرکت فرا صوت نگار :

Phone1: 66 72 33 80
Phone2: 66 72 36 46
Phone3: 66 72 56 63

E-mail:
info@farasoutnegar.com
milad@farasoutnegar.com
farasoutnegar@gmail.com

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نگاه رومی درباره Who has best sound in High-End Audio

یکشنبه ۵ دی ۱۳۸۹
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این مطلب رو هم باید تو انجمن مینوشتم و بنظرم ارزش نوشتن در سایت رو نداشت اما فعلا مجبورم اینجا بیارمش.

مطلب زیر رو رومی تو سایتش نوشته، بخونید :

http://www.goodsoundclub.com/Forums/ShowPost.aspx?postID=15286#15286

In the thread: “The industry-embraced audio and classical music” Stitch made a post that implied that the industry-sponsored indifferent sound is more attracted to the people who has a lot of money. I do not know how accurate that observation but it made me to think about the following:

Who in contemporary High-End Audio has the most persuasive and more able sound? I mean is somebody would like to demonstrate to Martians what definition of success in High-End Audio is then what kind people would be able to do it?

No, I do not ask about your or myself to reminiscent about where you heard the best results from audio. I more interested to know what type or an abstract group of people per capita has better audio result then other group.

I do not think that rich audio people have good sound, generally the folks with a lot of money, despite having a lot of expensive equipment do not demonstrate changing sound. Sure there are exceptions but we are taking about composite result for entire group.

Dealer’s show rooms are also very very very seldom demonstrating good sound, there are many reasons for, not to last of them that sales personals shall not be able to demonstrate sound more able then buyer can understand. This is, BTW, one of the reasons why high-end salon’s owners heir only audio- retards to work on the sales floor.

The recording pros have unquestionably great opportunity to be the group with the best sound. It is not the case as they grossly discard playback part of sound reproduction. Also, the majority of them look to have recording to be a replica of live event – a bogus approach – so they are disqualified.

Reviewing, editing and publishing staff is out of picture for multiple reasons, not the last one because they have too frequently revolving equipment and they hardly able to organize playback to use whatever they got.

DIYers mostly have very bad, very-very bad sound. Of course DIYers might be different level and among DIYers you can meat incredibly knowledgeable and talented armature-engineers. However, most of the DIYers among those who learned how to cut wood and how to solder do not have cultural listening and musical background to assess what they do and to comprehend what the values of own solutions.

The rich audio people devoted to brands and stay with great loyalty to a brand. People with less money do not dedicated to brand and labels but they devoted to specific marketing campaign. The history of high-end audio, as I observe it for the last 15 years, is a string of marketing campaigns that pre-developed and sold to spineless and non-ambitious public. If to look at the sonic results that average audio person get but to subtract from that result the chewed up and presold marketing objective then in most of the cases the Hi-Fi king will have naked body, destroyed by hard-progressing gummatous syphilis.

I can stratify many other groups but I think you have the point. I think in today audio world the audio groups that most likely have the best sound are personal installations of audio manufacturers.   Not the crap that they demonstrate at audio shows but their own home installations.

Unfortunately, the audio manufacturers are absolutely removed from the audio demonstrations.  The richest of them do have own dedicated demo room and this is very good. Unfortunately those manufacturers own listening rooms are not exposed to public and I feel it is very unfortunate. If I want o buy $100K speaker or amplifier then what would be more rational then to talk to the person who did it and let the person to demonstrate to me what the equipment is able to. The plain ticket, even to another side of globe cost virtually nothing in compare to the price that I am about to pay for the speaker or amplifier. Sure, the industry jumps out of skin to shut up a manufacturer and to assure public that audio can be hear only by train to sell stolen cars professional demonstrator. Sure, the industry does it as it where the 70% of murk up come from… The biggest problem however, is not the money but the fact the injecting itself into demonstration process the industry by many means (very loaded comment) kills the sound that would be possible to obtain from a raw product by other ways.

I do feel that manufacturers, as a group, have best sound among all industry groups. It is in way similar to the winery – you can get the best wine by learning from a given wine maker how to drink his wine and how to get it.

I wonder can an audio dealer to operate as traveling guide instead as a sale person?  If we looking for a reference end  the opportunity to experience the best possible result in sound reproduction then why do not deal with the environment what the best possible result most likely to appear?

Rgs, Romy the Cat

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