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Wayde
2015-07-25, 12:28
Just tried my squeezebox classic, the original, with some high bit-rate files had the coax digital output going into an external DAC that can displays the sampling rate. My 24/48 files displayed as 48k but so did 96k files.

I just wanted to check... does the squeezebox downsample prior to sending out the digital coax and/or optical?

Just to verify, it seems obvious to me but I want to double check... this means the external DAC is effectively not being used as the digital file is already being decoded into analog then it would have to be re-encoded into digital at a lesser sampling rate before being outputted through the coax/optical outs. I just want to verify that optical and coax behave the same and that my overall suspicion is that the external DAC is basically not being heard... if humans were able to hear such things (I'm not claiming to hear any difference, just wanting to understand the logic).

thanks for any help
Wayde

Julf
2015-07-25, 12:52
Just tried my squeezebox classic, the original, with some high bit-rate files had the coax digital output going into an external DAC that can displays the sampling rate. My 24/48 files displayed as 48k but so did 96k files.

I just wanted to check... does the squeezebox downsample prior to sending out the digital coax and/or optical?

There is a third-party add-on (EDO) that enables 96k output.

[edit: oops, just noticed you have a classic, not a touch - I don't think the classic can do 96k]


Just to verify, it seems obvious to me but I want to double check... this means the external DAC is effectively not being used as the digital file is already being decoded into analog then it would have to be re-encoded into digital at a lesser sampling rate before being outputted through the coax/optical outs. I just want to verify that optical and coax behave the same and that my overall suspicion is that the external DAC is basically not being heard... if humans were able to hear such things (I'm not claiming to hear any difference, just wanting to understand the logic).


No, the downsampling is done completely in the digital domain. The squeezebox still outputs digital, just not at the original rate.

Mnyb
2015-07-25, 13:13
Classic is 24/48 k .

But as julf says the dowsampling is digital and done by the server with a very good helper app called SoX . so yourr still hearingen your externas DAC . You are not a bat or a dog so 24/48 is not really a bottleneck .