General Asylum

Posted by KlausR. (A) on May 18, 2007 at 04:36:22

In Reply to: Re: "...does the public in general recognize the advantages and benefits of new formats. Apparently it doesn't." posted by tlyyra on May 17, 2007 at 09:18:14:

As a starter, read this

http://sjeng.org/ftp/SACD.pdf

Then, CD when properly dithered has a dynamic range of 115 dB. SACD offers 120 dB. But you'd also want to reproduce that range.

Now look at what the amp power requirements are for various SPL (an enlarged version of the table is available in the link)

See what I mean?

Then, how loud can a given speaker play whilst keeping distortion levels low?

Klaus

• Power - How Much Do You Really Need?   (Open in New Window)

• Re: hi-rez is increased definition and dynamics - tlyyra 05:54:57 05/18/07 (2)
  In Reply to: Re: hi-rez is increased definition and dynamics posted by KlausR. on May 18, 2007 at 04:36:22:

  Good questions. (And incidentally I was just reading Lipshitz & Vanderkooy in another context - so, that much for the weekend doing gardening.) That would surely put these benefits out of the hearing range for most of us. I think the cumulative thrust of your points speaks in favor of better solutions in our audio systems, such as well-engineered active speakers, if we want to enjoy that fabulous extra 5 dB and all the other improvements to their max.

  TL
  
  

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  • Re: better solutions in our audio systems - KlausR. 06:19:11 05/18/07 (1)
    In Reply to: Re: hi-rez is increased definition and dynamics posted by tlyyra on May 18, 2007 at 05:54:57:

    In active speakers the amps are driving an inductive load, in a passive speaker the amp is driving a reactive load, which, according to Brad Meyer, increases the current demands on the amp to as much as several times that demanded by a simple resistor. In his article about active speakers Bob Stuart mentions a factor 3. Which would mean that the 400 Watt amp, as used in my speakers for the bass driver (8 Ohm, 98 dB), equals to a 1200 Watt outboard amp.

    So if you want live-like reproduction you not only need live-like timbre but also live-like SPL. Hence BIG power amps for those who have inefficient speakers. So why do audiophiles stick to those technically obsolete solutions?

    
    Klaus
    
    

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    • Re: better solutions in our audio systems - tlyyra 07:55:53 05/18/07 (0)
      In Reply to: Re: better solutions in our audio systems posted by KlausR. on May 18, 2007 at 06:19:11:

      To say nothing of the fact that in active applications, the speaker designer would have probably also had a big say in the design of the amps as well (if not wholly designed them from the scratch) that drive those speakers, i.e. matched them optimally together. Which would render the whole issue of external-amp matching a moot point (along with all that speaker cable mystique). A big headache gone for good for all audiophiles, and a lot more time and money left for music!

      TL
      
      

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