Adding a component with an AD/DA stage downstream from your DAC...‍♂️

[MDAguy]

So I listen in a smallish room (Can't change that for a multitude of reasons) with some acoustic issues, nothing too bad, but I'm trying to achieve the best possible sound in this room... ... a friend brought his DSP (Accuphase DG-58) over and we tried it out, and it made a noticeable and overall good difference...especially when listening at louder volumes oddly... this prompted me to order a one for myself at a crazy good discount as I've always liked the idea of a good quality EQ anyway and I'm a huge fan of Accuphase. Turns out the newer version was available.. (Accuphase DG68)... It doesn't arrive fro 2-3 weeks, but reading thru the brochure on their website, it seems to mainly recommend installing the DSP in between my Pre-Amp and my Amp.. (see diagram).

So in effect, if I'm listening to streaming music, CD or whatever else, as all my music is digital in source/origin, the digital data is processed by my DAC, then outputted into the pre-amp (XLR Balance)... then later re-inputed into the DSP which coverts it to digital to do it's magic, and back into analogue to send to the amplifier. So that's two visits to the digital domain, right? The DAC first turns digital to analogue, then outputs that into the pre-amp, which then sends it to the DSP that turns it back into digital.. etc..

On one hand, I've heard for myself that it's predecessor DG-58 sounded amazing in that spot...on the other hand, I think if I just invest in a $1200 streamer and renderer such as the Roon Nucleus, I can then shift the position of the DSP to before the DAC and thus stay in the digital domain only once, then return to analogue and not return to digital again ...

Am I being overly picky? OCD? Is the way Accuphase recommends it being installed truly the best way?

 

[sergeauckland]

It may not be the best way technically, but it's the best way practically. ADC-DAC functionality is totally transparent, and has been for at least 25 years now, if not more, so there's absolutely no reason why one shouldn't do it.

Doing it any another way may mean having to arrange a digital volume control and/or ADC for analogue sources, so may be less practical.

In my own system, I have DACs on my digital players, going through a conventional pre-amp then ADC-DAC pairs on my active 'speakers. It's a lot easier that way than arranging for a 6 way analogue volume control after the active crossovers just to save one additional conversion.

S.

 

[MDAguy]

ADC-DAC functionality is totally transparent, and has been for at least 25 years now, if not more, so there's absolutely no reason why one shouldn't do it.

S.

and that's just it, the unit in question is known to be quite transparent .. so I'm just being silly probably, and the purist mentality is driving this anxiety.

 

[Blumlein 88]

https://www.audiosciencereview.com/...dac-loop-vs-the-original-can-you-hear-it.448/

https://www.audiosciencereview.com/...-choose-the-8th-generation-digital-copy.6827/

Try listening to these files. These are 8th generation copies. They have been thru 8 loops of DAC to ADC and through again.

Much lesser gear than what you'll be using for one loop.

 

[Katji]

^^^ "Trust your ears"?

 

[MDAguy]

Fascinating study Blumlein 88... So in effect hard if not impossible to tell, but I'm curious was there a difference in the two when you measured them in any sort of way? Could the argument be made that there was measurable degradation from each conversion, or essentially they were identical?

 

[gvl]

You can also use an all-digital solution upstream of the DAC, but it won't work for SACDs.

 

[Katji]

I resolved the issue, but way below the context of Accuphase. In that context, I'd easily convince myself. If I afford it, I'd resolve it by getting Avantgarde Zero. (I'm assuming any ADC in it is not applicable unless you use a turntable or some other analog source with it.)

 

[sergeauckland]

and that's just it, the unit in question is known to be quite transparent .. so I'm just being silly probably, and the purist mentality is driving this anxiety.

Probably!

S.

 

[MDAguy]

You can also use an all-digital solution upstream of the DAC, but it won't work for SACDs.

essentially that would require me to buy a dedicated streamer/renderer such as the Roon Nuc... which at $1300 I'm a bit hesitant to do when I have a perfectly good one with with my dCS Rossini, but using that has proven to be a mess (see attached file).

 

[Blumlein 88]

Fascinating study Blumlein 88... So in effect hard if not impossible to tell, but I'm curious was there a difference in the two when you measured them in any sort of way? Could the argument be made that there was measurable degradation from each conversion, or essentially they were identical?

In one case the ADC had slight FR ripple in the top octave. Not much, but over 8 generations it is slightly audible as the ripple grows with each copy.

In the other case the response is flat and I can hear no difference.

I did include some tones when I did this. The noise floor rises close to the 3db per copy you would expect. Distortion rises too. Even with these modest devices it is low enough not to be an issue. Phase of the top octave is mangled, but we aren't very sensitive to that. I used two separate devices so the clocks were not locked. I assume jitter accumulated with each pass for this reason.

 

[gvl]

essentially that would require me to buy a dedicated streamer/renderer such as the Roon Nuc... which at $1300 I'm a bit hesitant to do when I have a perfectly good one with with my dCS Rossini, but using that has proven to be a mess (see attached file).

I wish DAC/streamer combos offered a SPDIF output so it would be easy to integrate third party DSP in the loop.

 

[MDAguy]

I wish DAC/streamer combos offered a SPDIF output so it would be easy to integrate third party DSP in the loop.

You would think that would be a given, especially on a $23999 unit... kinda pissed it's not.