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Re: Stereo > Mono Downmixing on iOS
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Re: Stereo > Mono Downmixing on iOS


  • Subject: Re: Stereo > Mono Downmixing on iOS
  • From: tahome izwah <email@hidden>
  • Date: Tue, 05 Apr 2011 14:27:59 +0200

2011/4/4 Brian Willoughby <email@hidden>:
>
> On Apr 3, 2011, at 23:49, tahome izwah wrote:
>>
>> Care to share any pointers?
>
>
> Sample Rate Conversion is one good example.  See:
>
> http://src.infinitewave.ca/
>
> Apple's AudioConverter SRC in CoreAudio comes in very close to the top of
> the list in quality.  That site does not strictly have a "list" but you can
> browse the various SRC implementations and find the best performers
> interactively.  That said, the iZotope 64-bit SRC is just about the only one
> which outdoes Apple's (presumably 32-bit) implementation.  I'm fairly
> certain that the 64-bit implementation is the bulk of the reason for the
> increased performance.  Note the noise floor of 24-bit and 32-bit SRC
> algorithms, and compare the nearly-silent 64-bit implementation.

"Nearly silent" is a matter of context. For everything I've done so
far 32 bit floating point precision has always been "enough" (another
POV term). IMHO, nobody can reproduce let alone actually hear noise
below -100 dB DFS in a digital system so I was curious if there is
really some sort of double blind study that would clearly show that
64bit is better than 32bit from a perceptual perspective. Of course,
you can never use too many bits, but I have always been more inclined
to doubt the usefulness of doubling the bandwidth in practice. Hi end
audio and voodoo seem to have a lot in common, and unless someone can
really provide some shred of proof that 64bit is really making my DSP
sound better I'll happily settle for using twice the bus bandwidth to
provide good sound instead of halving it to provide supposedly better
sound.

My 2 cents, FWIW
--th
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  • Follow-Ups:
    • Re: Stereo > Mono Downmixing on iOS
      • From: Brian Willoughby <email@hidden>
References: 
 >Re: Stereo > Mono Downmixing on iOS (From: Bob Lang <email@hidden>)
 >Re: Stereo > Mono Downmixing on iOS (From: Roman Thilenius <email@hidden>)
 >Re: Stereo > Mono Downmixing on iOS (From: Richard Dobson <email@hidden>)
 >Re: Stereo > Mono Downmixing on iOS (From: tahome izwah <email@hidden>)
 >Re: Stereo > Mono Downmixing on iOS (From: Brian Willoughby <email@hidden>)

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