8ch dac for AL and Roon?

jtwrace

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Maybe it is just me, but I don't understand how you will get an RPi based audio source to work with Audiolense?
RPi is the endpoint for Roon which has the Convolver for AL.

 

jjazdk

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RPi is the endpoint for Roon which has the Convolver for AL.


Ahh... I assumed you where using the Audiolense Convolver, which you clearly are not. Now I understand.

If RPi's have difficulty with USB sound cards, I would discard the RPi solution for good.
 

jtwrace

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Ahh... I assumed you where using the Audiolense Convolver, which you clearly are not. Now I understand.

If RPi's have difficulty with USB sound cards, I would discard the RPi solution for good.
I will not run a hardwired connection. So that basically leaves the Okto and exaSound s88. I was hoping for a surprise. :)
 

2234rew

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If RPi's have difficulty with USB sound cards, I would discard the RPi solution for good.

Most pro audio interfaces don't do well with Linux for over 2 channels (not officially supported).

So it's not an RPi specific problem. Moreo Linux support
 

2234rew

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A good forum for pro audio Linux users:


There are some manual patches created by very clever people for multichannel but I wouldn't do this personally.

I don't want any unexpected static sound / big pop sound during music playback, due to a manual hack that's not been fully tested by the interface maker.
 

Omid

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Just a small correction.
When I talked about my MOTU DAC I said I use Roon's DSP volume which is 'not ideal'. I stand corrected. It turns out Roon's DSP volume control is apparently better than a harde wired volume control:
 

2234rew

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Just a small correction.
When I talked about my MOTU DAC I said I use Roon's DSP volume which is 'not ideal'. I stand corrected. It turns out Roon's DSP volume control is apparently better than a harde wired volume control:

Please correct me if I misunderstand but on his final page of his whitepaper he even mentions if your power amp has SNR = 100dB, then 30dB digital attenuation will result in best case SNR = 70dB.

A transparent analogue volume control should allow you to maintain SNR = 100dB of the power amp ? As long as this preamp is not the weakest link (hence transparent) ?
 

Omid

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Please correct me if I misunderstand but on his final page of his whitepaper he even mentions if your power amp has SNR = 100dB, then 30dB digital attenuation will result in best case SNR = 70dB.

A transparent analogue volume control should allow you to maintain SNR = 100dB of the power amp ? As long as this preamp is not the weakest link (hence transparent) ?

I’m not sure I understood your question. can you explain a bit more?

I think he’s saying that Roon has a lower noise floor than a pre-amp (esp with a 24bit signal), but that in the end it’s irrelevant since an amp’s noise floor is high enough that unless you listen full blast the dynamic range will be limited anyway (70dB in his example).
 

2234rew

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I’m not sure I understood your question. can you explain a bit more?

I think he’s saying that Roon has a lower noise floor than a pre-amp (esp with a 24bit signal),

Noted, I interpret his entire whitepaper as showing Roon's volume control is as lossless as any digital volume control needs to be.

But there are analogue pre-amps with better than 100dB SNR. So matched with SNR 100dB power amp, then in theory allows SNR = 100dB at the listening position when digital volume control is at max setting.

But I may misunderstand his whitepaper.
 

Omid

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In the example of a preamp with -100dB SNR, the noise floor is at -100dB, fixed, regardless of the signal amplitude. If you play a full volume signal, the ratio of signal to noise is 100dB. If you turn the volume down, the signal is reduced by say 30dB. The noise floor does not go down with it, the signal to noise ratio is thus reduced to 70dB.
 

juicehifi

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The Roon paper is pretty good, IMO, since it takes any scepticism against digital volume serious.

My take on this is that a digital attenuator that operates at 24 bit int, 32 bit float or higher is practically transparent as long as the rest of the digital chain never drops below 24bit int (or 32 bit float) …. which is hardly ever the case with today’s converters. You will lose dynamic range at very low level, but what you loose will be way below the threshold of hearing.
 

juicehifi

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It is true what you say, provided the analog attenuator is 100% transparent, which is highly unlikely. With an analog stepped attenuator you will typically either have an extra buffer behind …. or effectively a «passive» solution hooked to the amp. Both of these will often reduce the sound quality.

It is very difficult to beat a digital volume, folkowed by a sota dac directly hooked up to the power stage.
 

menlobob

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RPi is the endpoint for Roon which has the Convolver for AL.

Have you thought about running Roon Bridge on something like a used Mac Mini? The 2012 ones can be had for $200 these days. This would give you a Roon remote endpoint with the great driver support of MacOS for pro audio gear.
 

jtwrace

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Have you thought about running Roon Bridge on something like a used Mac Mini? The 2012 ones can be had for $200 these days. This would give you a Roon remote endpoint with the great driver support of MacOS for pro audio gear.
Thanks. Mac Mini really didn't interest me actually. I built a W10 NUCi7 which works great!
 

Badbruno

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jtwrace

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jtwrace

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Hi @jtwrace. Just checking, are you using your NUC as a Roon Bridge here or you have the Roon Server directly on it? I’m on the same boat. Thanks!
Yep, NUC (Roon Server) directly connected via USB - C to the Motu.
 

Badbruno

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I have a mint exaSound e38 with the latest firmware from exaSound. I just had it updated at factory

contact me if your interested
 

jtwrace

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(2) Rythmik FM8, (1) UM18, (1) Custom DIY Ciare 18
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All Belden 1800F and 1313A

jtwrace

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(4) Hypex NC502MP
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Topping D90
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JBL M2
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(2) Rythmik FM8, (1) UM18, (1) Custom DIY Ciare 18
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BSS BLU 50
Other Equipment
All Belden 1800F and 1313A
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