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Re: Native sample rate
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Re: Native sample rate


  • Subject: Re: Native sample rate
  • From: "Mikael Hakman" <email@hidden>
  • Date: Tue, 22 Jul 2008 02:47:22 +0200
  • Organization: Datakonsulten AB

I know at least one hardware device with corresponding device driver which doesn't listen to SR change requests. It pretends that it supports a number of rates but it's doing SRC to one and the same before feeding its DAC and/or S/PDIF interface. If you use its "real rate" you get THDN in order of -94 dB but if you use the other rates THDN goes up to -60 - -40 dB (also on S/PDIF!) depending on audio frequency - its spectrogram is a disaster. In addition that device is advertised as HD audio device! Fortunately, running this device under another operating system restores its full capabilities - it's the driver that faults, not the hardware.

Regards/Mikael

On Tuesday, July 22, 2008 12:18 AM, alejandro wrote:

Mike,

Hardware oscillator are always divided to obtain audio sample rates, so there is nothing like a 'nominal' sample rate.
Interpolation (sample rate conversion) is only performed when the audio file sample rate differs from the audio device rate. So if you want to avoid sample rate conversion for quality reasons, you can change the device sample rate to match the audio file rate.


Alejandro

--
Alejandro Palencia
Open Studio Networks
+34 667 440 770

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 >Re: Native sample rate (From: alejandro <email@hidden>)

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