DSP - does it defeat the object of expensive analogue sources?

[andreasmaaan]

I shall endeavour to confirm, insofar as my Miltary Grade OCD allows!

If the AD-DA is effectively transparent, as you suggest and I hope, then I will be comparing the Chord plus cables to the IAP in terms of their DAC performance alone, which will be interesting to say the least

Sounds good! You might find it easier to record the output of the Chord through the ADC of the IAP (if it's possible to that), and then use a software ABX comparator e.g. in Foobar to compare the recorded output from the Chord to the original digital file.

*easier in terms of not having to deal with hardware switching etc.

 

[Sir Sanders Zingmore]

Thanks for the input

My setup is as follows:

Source is a home built, passive cooled, low power Linux based Roon endpoint with separate Teddy Pardo PSUs for the main board and SotM USB card

This outputs over USB to Chord Blu2/DAC, then analogue to an Illusonic IAP4 that does the DRC and crossovers, thence to x2 Sanders Magtech amps. Speakers are Sanders Model 10 electrostatic/transmission line hybrids (no digital in)

Balanced transformer on the mains and a LessLoss bespoke x6 power distribution block

I have run this over and over in my mind and my options, if I want to keep it all analogue after the DAC, are limited I think

Something like a DEQX pre DAC to do the DRC, then a Marchand XM44 seems to be the only option I can find to do the crossovers. Whilst I don't for a second doubt they are a quality piece of kit, I am unsure as to whether in terms of simply being a crossover they will outperform the DSP in the Illusonic

Unfortunately it's quite an expensive test to run and may leave me with some niche, redundant kit !!

When I had a full Sanders system it had a behringer DCX as the crossover (before Roger upgraded to the illusonic).

I tried a few different things.
As far as I could tell, the AD-DA is completely transparent. My turntable still sounded like my turntable. Different DACs still sounded (subjectively) different. In other words don’t worry about the additional conversion...

I also tried a deqx unit as I thought having DAC, preamp, crossover and DRC in one box would be an improvement. I returned the unit for two reasons:
- I felt that the DRC provided by Acourate was better than the deqx (at a fraction of the price)
- the deqx unit volume control was not fine enough. It was always a little too quiet or a little too loud.

I would not go with an analog crossover like the Marchand. You’ll lose the very careful time-alignment that Roger has done. IMHO, this is absolutely critical for the seamless integration between the bass units and the panels.

 

[babysnake]

As far as I could tell, the AD-DA is completely transparent. My turntable still sounded like my turntable. Different DACs still sounded (subjectively) different. In other words don’t worry about the additional conversion...

That's very reassuring (hooray for confirmation bias ) and certainly does chime with a lot of the other stuff I've read about how transparent AD-DA really is now, including @andreasmaaan here

I would not go with an analog crossover like the Marchand. You’ll lose the very careful time-alignment that Roger has done. IMHO, this is absolutely critical for the seamless integration between the bass units and the panels.

When I suggested to Roger I move away from DSP crossovers he was typically blunt in his disapproval for exactly the reasons you state

 

[Blumlein 88]

If there is validity to chords special filtering, it is being undone by the extra conversions in the illusonic. So I'd say go direct in via USB

 

[Purité Audio]

There isn’t.
keith

 

[Old Listener]

MThe "PRAT" you are perceiving is unlikely to hold under blind conditions.

PRATfall?

PRATfail?

 

[babysnake]

If there is validity to chords special filtering, it is being undone by the extra conversions in the illusonic. So I'd say go direct in via USB

Absolutely fair comment and the exact reason I am asking the question. Am I 'undoing' all the percieved good work of the Chord combo?

If the AD-DA in the IAP4 degrades the input analogue signal, it will do so reliably, and to the same degree, to every analogue source (ie: every DAC)

So I should expect to be able to hear the differences between DACs, even given that they are all performing sub-optimally to a degree determined by the IAP

Also given that I have a certain taste in music and consider certain facets of musical reproduction more subjectively valuable than others, I could 'rank' the DACs in terms of personal preference. This 'ranking' has no value outside my listening pleasure

I have access to a handful of decent quality DACs (a couple FPGA, ditto R2Rs and an ESS ) and will try this out

As part of that I will see if I prefer the Chord combo to the IAP direct option and feedback here in due course

 

[Purité Audio]

Do you absorb/diffuse the rear output from the Sanders?
Keith

 

[hvbias]

Me too...
Most of these AD to DA are transparent these days .. YEt .. something ..just something in the notion of multiple conversions takes hold in our minds and deter from fully enjoying our systems ... Bunch of OCD people

At the Original Poster. The Chord seems to be redundant in this scheme ... The "PRAT" you are perceiving is unlikely to hold under blind conditions.

Haha you and @Cosmik are brave for speaking up on this. I too would prefer if my system was just D (convolution) -> A even if I knew I wouldn't be able to hear the DA/AD/T&A.

 

[watchnerd]

All of my systems have at least one dual DA or AD stage.

DAW / office system:

USB out -> RME ADI-2 Pro ADDA -> analog out -> Dynaudio Lyd 5 (ADC, DSP crossover)

Living Room:

(when listening to LP, as opposed to streaming)

Cartridge -> analog in -> ADC -> DSP RIAA, digital volume control, other EQ -> DAC-AHD amplification -> Dynaudio Contour 20s

It's not theoretically ideal, but...

1. The DSP crossovers vs passive and are worth the extra "cost" and sound awesome
2. The DSP RIAA phono stage is more transparent than any analog phono stage I've heard

Unsurprisingly, a good ADC can preserve the analog qualities of a source (duh...given how many digitized recordings were originally made in analog) and the DSP benefits to crossovers and EQ give it far fewer downsides than the analog equivalents.

I love analog sound, but analog purists are missing out if they refuse to try combining the two.....good digital playback is more transparent to analog sources than than analog playback alone.

 

[watchnerd]

As far as I could tell, the AD-DA is completely transparent. My turntable still sounded like my turntable.

Ditto.

In fact, it would be a pretty bad ADC if a turntable didn't.

 

[babysnake]

Do you absorb/diffuse the rear output from the Sanders?
Keith

No

On the advice of the designer, in fairness

 

[Sir Sanders Zingmore]

No

On the advice of the designer, in fairness

You should ask the designer his views on DACs

 

[Old Listener]

All of my systems have at least one dual DA or AD stage.

DAW / office system:

USB out -> RME ADI-2 Pro ADDA -> analog out -> Dynaudio Lyd 5 (ADC, DSP crossover)

It's not theoretically ideal, but...

1. The DSP crossovers vs passive and are worth the extra "cost" and sound awesome
2. The DSP RIAA phono stage is more transparent than any analog phono stage I've heard

Unsurprisingly, a good ADC can preserve the analog qualities of a source (duh...given how many digitized recordings were originally made in analog) and the DSP benefits to crossovers and EQ give it far few downsides than the analog equivalents.

A system with more than one D to A stage may be the best solution overall for an individual's needs. I'm for pragmatic thinking about real world alternatives rather than blind adherence to doctrine.

 

[restorer-john]

...Do you absorb/diffuse the rear output from the Sanders?..

Bernie Sanders or Colonel Sanders?

The Colon-el wouldn't need it- he's long gone.

Buy him a 5 pack of these, about $12:

 

[Sal1950]

So I should expect to be able to hear the differences between DACs, even given that they are all performing sub-optimally to a degree determined by the IAP

Quality modern DAC's don't sound different, if some do (are not transparent) they are doing something wrong, or you expectation bias is making you hear something that isn't there.
More to the point which has been hit on a few times here, if you had a telescope with the best optics in the world but then somewhere in the chain introduced a poorly done piece of glass, the best it will ever do is again going to be controled by that weakest link. Anything less than 100% perfect transparency is then going to be the order of the day.
Why leave anything in the chain not completely nessacary?

 

[JJB70]

Bernie Sanders or Colonel Sanders?

View attachment 17513

The Colon-el wouldn't need it- he's long gone.

View attachment 17516

Buy him a 5 pack of these, about $12:

View attachment 17511

I'll take the colonel, at least his artery clogging deep fried junk serve some sort of purpose. Even if it's just to remind you that you shouldn't be eating such crap.

 

[babysnake]

Quality modern DAC's don't sound different ...

If one defines a DAC as a pice of hifi kit sitting on your shelf, then I beg to differ. That is not my own experience and I struggle with the idea that across a range of prices from say £1000 to £50 000 all DACs sound the same. That's an entire industry almost built on quicksand, even after you allow for hype and marketing !

I do, however, accept that all modern DAC chips might well measure the same, but that is not how I interpreted this response

It looks like from a theoretical perspective unnecessary AD-DA stages are just that, unnecessary, but that the practical audible advantages of DSP in terms of crossovers, say, outweighs the currently available analogue alternatives

Hence, as per @watchnerd, they can be viewed as a necessary evil, if i can put it like that

 

[andreasmaaan]

That's an entire industry almost built on quicksand

Precisely

It looks like from a theoretical perspective unnecessary AD-DA stages are just that, unnecessary, but that the practical audible advantages of DSP in terms of crossovers, say, outweighs the currently available analogue alternatives

Also correct.

 

[Sal1950]

If one defines a DAC as a pice of hifi kit sitting on your shelf, then I beg to differ. That is not my own experience and I struggle with the idea that across a range of prices from say £1000 to £50 000 all DACs sound the same. That's an entire industry almost built on quicksand, even after you allow for hype and marketing !

Compare them all under tightly bias controlled blind listening conditions.
If any prove to sound audibly different, then conventional measurements will reveal exactly why. (and who might be playing funny games)
There is no magic dust,
That's just the facts of the issue.

It looks like from a theoretical perspective unnecessary AD-DA stages are just that, unnecessary, but that the practical audible advantages of DSP in terms of crossovers, say, outweighs the currently available analogue alternatives

Any tone control inserted into a system that makes it sound better to the listener is perfectly acceptable.
Others may disagree on the results.