DAC Manufacturer Aversion To External DSP

[Albrecht]

On 7/1/2020 at 5:49 AM, The Computer Audiophile said:

Hi Guys, I’ve been thinking about this topic for a while and think perhaps a good discussion may be enlightening. 
 

The vast majority of manufacturers I talk to have a serious aversion to people using apps such as HQPlayer to use filters and modulators of their own choosing before sending audio to the components. 
 

Some manufacturers suggest they know best and that anything other than what’s being done inside the DAC can’t provide better sound. Others say that choice is confusing and most users select a single filter anyway, so they provide that one in their DACs. 
 

I’m a huge fan of choice and would prefer a DAC that enables the best of both worlds, the manufacturers best and the option to select what I think is best externally. 
 

Have others run into this aversion from manufacturers and heard good reasons for it? I’m not suggesting there is a right or wrong way to design, produce, and sell a product. I’m just very interested in understanding why decisions are made, especially when those decisions limit choice. 

Hi,

This is a topic that I've always found interesting and thank you for introducing this....

 

I think that in some ways, it can go back to, and perhaps be a part of that notion of design goals. (And I'm talking about applying DAC design as being similar to speaker design). Surely, - Wilson Audio has a very different "take" or opinion about what is good sound than Verity Audio. To be clear, - both are excellently designed speakers, yet they sound nothing like each other. The Halcro amps sounded nothing LAMM....

 

I remember talking to the designer of Jadis amps at CES one year where he pointed out that he builds amps that work with speakers that make Tchiavosky sound "right." He told me that he doesn't give a shit about how the Patricia Barber recordings sound. He hated Patricia Barber, and if you like Patricia Barber, - don't buy my amps...

 

I think that we have to consider a similar thing with DACs, - in that they are part of a system wherein the manufacturer may be focusing on a particular sound that they want to hear. If a customer "mis-applies" their DAC to the wrong speakers and amps, - does that mean that the DAC is not "well-engineered?"

 

Finally, - many of these manufacturers may feel, (and people have said this), that there are a lot of sources out there, - one cannot possibly ever know what a consumer is going to plug into it. Certainly a USB audio signal coming from a shite USB bus directly from a MACMini is very, very, different than one coming from a SoTM or an Optical Rendu. 

A DAC manufacturer can't, and shouldn't design their DAC's USB input with a galvanic isolation "moat" on the USB receiver when one isn't needed. And besides, - the inputs on any DAC are just one of several "parts" of the DAC that can and do affect the final outcome. 

Finally, the DAC is just part of "system." Even the best DACs could possibly perform poorly when paired with the "wrong" amps and speakers. 

[Albrecht]

On 7/6/2020 at 4:57 AM, 4est said:

I do not see what software has to do with USB cables and regeneration hardware. Furthermore, PCM to PCM upsampling does not require a lot of processing power.

FWIW, I so agree....

This is something that is almost to absurd to quantify,  - (but just to make a point), -  software accounts for a small percentage of SQ difference. You have to go waaaay down in level of speakers and amps before a Schiit sounds like a Meitner. DSP whether inside or outside doesn't play into the fact that everything else about a Schiit DAC is not even close to the SQ. I think that we see too many people here losing perspective on lateral moves with $2000 price point gear, - thinking that they've got a giant killer, - instead of racking up those experiences that they need to place gear in it's proper spot.

(This means listening to really SOTA stuff as well as really lo-fi stuff). 

The fact that there were many people who touted the Singxer SU-1 was so much better than the 10  times more expensive Audiophelo USB-to-SPDIF converter was not JUST due to XMOS firmware/software, but due to the Singxer's excellent isolation moat, and excellent clock

 

IMO, - everyone has learned a LOT from the Singxer SU-1, and products like the Intona, - which is NOT a product built by and for high performance audio manufacturers. Refining products like this and improving them makes this such a "fluid" field of study, - that it's almost stupid for a DAC manufacturer to build-in an USB port. 

 

Is there anyone who would spend $20K on a Meitner and plug in a Belden USB cable from a MacMini on their audio rack?

[Albrecht]

2 hours ago, barrows said:

Source and cable still matters, why would it not?  This is no indication of there being anything "wrong" with USB as an interface. In fact, USB is the best digital interface we currently have for audio, yes, some USB inputs are better than others, as is the case with any input.

SPDIF: cables matter

Analog inputs: cables matter

Ethernet inputs: apparently, cables matter

 

just like any input, it can be done well, or not, thta is up the engineering.  But there is nothing inherently wrong with USB.

I think that it is ironic that by utilizing computers, or mini-computers: people somehow think that they are getting better sound for cheaper: hardware is no longer important, and good sound has "advanced" for a much much cheaper price.

It's almost as if power supplies no longer matter, pre-amps don't matter, cheap-ass resistors with huge variances don't matter.....

 

It's like the analogy of disc transports: where-in, because of software/firmware correction, Plextor transports (designed for another application), are fine, there's no need for VRDS Neo, - they all sound the same: error correction fixes it all. But when it's actually tested and compared, - reality emerges.

 

the fact is that Schiit products sound EXACTLY like their parts employed, and just like every other $2000 DAC when compared to a SOtA DAC like a Meitner, they fit right into where they belong, - in an upper mid-end to low hi-end scheme with other $2000 speakers amps, and MacMinis and Dell Optiplexs. They NEVER belong with Verity/Wilson/Kharma & LAMM/VAC/Nagra etc. 

 

An un-treated USB signal coming from a Dell Optiplex USB bus, or a MacMini USB bus designed for printers, mice, (two way comms) etc., - sucks for high quality 4K video and high performance audio. This was not only proven by high performance audio manufacturers, - but by computer industry manufacturers.... Look at products by Intona, EMO Systems, and Icron.

With folks who think that they are getting something for nothing, - it's no wonder that manufacturers punt. There is a huge difference in the USB stream coming from MacMini vs a Sonore Signature Rendu. And if I was a manufacturer like Ed Meitner, - I"d NEVER put an USB B input on any of my DACs. 

[Albrecht]

1 hour ago, barrows said:

I disagree with this.  The same could be said for any digital input on a DAC.  I mean, there are plenty of terrible sources with Toslink output, or SPDIF or AES... (and not even considering how bad HDMI is by design...)

If you are making a DAC, you have to put some kind of input on it.  Of course it is probably wise to advise your customers that source quality will make a difference in the ultimate performance of the product.  Despite every effort of every DAC manufacturer who claims that their DAC is immune to source quality, i have never experienced such a DAC, and I have played with a lot of DACs over the last 15 years or so.  Some DACs are certainly better in this regard than others, but none of my experience have been immune to the source quality.

I hear what you are saying, - but please do not think that I am saying that USB is horrible. I am also not saying that ALL input methods/signals do not have their flaws.

 

I am saying that USB is still quite young in its development, - and there are new developments happening, - something that DAC manufacturers would be foolish to try and keep up with. As I wrote before, - DAC manufacturers cannot predict what kind of QUALITY USB signal is being fed to their DAC. That "job" is the duty of the digital file player. 

 

USB has more POTENTIAL to be mis-applied than SPDIF COAX. SPDIF COAX sure does have it's limitations as well. I2s does also. But in this world of trying to get something for nothing, - people are still putting computers designed to run Email/Photoshop/Netflix on their audio rack. 

[Albrecht]

On 7/11/2020 at 3:20 AM, R1200CL said:

A standard or preferred DAC interface for external DSP is important. 
 

Both USB and HMDI requires the noisy processing computer close to the DAC. 
It’s my understanding we like to have that PC far away from our DAC. 
 

John S design with Sonore’s Redus is one of few products that solves this. 
 

It seems quite clear to me that only Ethernet with fiber can be the future way for DAC manufacturers that like to allow for external DSP. 

 

I would still like to understand why HMDI shouldn’t be implemented as an interface for DACs, as I like my DAC to be used in conjunction with TV or TV boxes. I would prefer HMDI in and out, so after my DAC has collected sound, the signal can go to TV. (Or even another multichannel DAC). 

Also it’s my understanding that HMDI will allow for SACD transports.

 

Can the SACD be up sampled in the external PC, and signal sent over Ethernet?

(Not ripping, but you insert it in the drive of your PC, assuming there is SACD drives on the marked). 

Both USB and HMDI requires the noisy processing computer close to the DAC. 
It’s my understanding we like to have that PC far away from our DAC. 

 

that is 100% not true, - in any way whatsover....

 

there are at least 5 to 10 products that one can purchase right now that make that statement almost silly...

 

HDMI connectors can be used for many things. HDMI is not a protocol but a piece of hardware. 

 

[Albrecht]

On 7/11/2020 at 11:31 AM, 4est said:

Perhaps you should read the original post. HQPlayer is precisely what this thread is about, and by extension the hardware requirements seem on topic. Regardless, it the OP's call.

With respect, - I must be confused, - as I thought that the topic was "manufacturers aversion to external DSP" 

 

this would include, - in my mind, - how I took it as a hardware discussion, - about why manufacturers don't build in things like galvanic isolation "moats" into their USB inputs. I recognize that this include USB processing software like exists with HQPlayer. 

 

(It seems like I am cray, didn't read carefully, or made a grossly wrong assumption about this being primarily a hardware discussion). 

 

the ONLY reason to ever use HQPlayer in my mind is to get DSD, - and some people don't have that capability or the recordings to do so. If I want DSD level performance, - I am going to go get it from APL, - who is the expert on this stuff. I have had the DirectStream DAC in my system, - and well.... it's not a product that "belongs" with the rest of my system. 

 

I have no experience with HQ Player. So, - it would be wrong to comment on it in any way. Just like hardware, (which is prolly something like 80 to 90% of any final product), that should be addressed first IMO.

 

I don't know how many folks are or are not comparing $2K Schiit DACs to $2K Audio Aero Prima's with a Singxer SU-1 from 20 years ago: but i bet that many people would be very very surprised.....

[Albrecht]

4 minutes ago, Miska said:

 

HDMI is pretty strictly defined standard for transporting video and piggybacking audio on top of video (in vertical refresh isles in the data stream). It defines exactly how audio clocking is done, what audio formats are supported and how much audio data can be sent with certain video resolutions. And how to calculate audio clocks from the video pixel clock. I have HDMI specification documents and I have read through those.

 

Use of HDMI connectors and cabling for LVDS I2S has nothing to do with HDMI whatsoever.

 

As i wrote....

[Albrecht]

1 minute ago, Miska said:

 

With modern delta-sigma converters, DSP side plays major part of the performance. The whole idea is to simplify hardware side by moving as much as possible to digital domain processing where you are not restricted similar way as hardware/analog world is.

 

FWIW, - I think that you make a valid point that is well worth considering.

 

I do have to say that a DAC is not only digital to analog conversion, - or digital FPGA processing that is so close to analog that it "works" without a traditional analog output stage.

 

Most DACs that do not have "convert everything imputed to DSD have much more going on than digital conversion..... It is an analog stage and pre-amp/volume control, it is the power supply(s) it is the design, - case, - vibration control etc. 

 

On this earth, - there's no way to make a Schiit sound like a Meitner, - (even 25 year old Meitners), - unless you go waaaaaaay down into BoomBox-style associated equipment.

 

Because of the above, IME, - this does go down to DAC processing too, - (i guess in a little contradiction to what I said above). In that, - I've never heard any Sabre DAC implementation sound "right." And, - I do believe that it is possible to make a Sabre chip(s) sound right with processing and really good output stages, and power supplies, - all things being equal, - DACs with Sabre chips don't sound right compared to AKM and other implementations. 

 

A Mac Mini was designed for purposes other than high performance audio. One can't say that a MacMini sucks. That would be unfair. But what you can say that a MacMini sucks for high-performance audio. The shitty (for HP audio) USB bus is just one factor. The hard drive motors, the CD Rom drive, (if there is one), the hard drive bus, the video stage, all contribute to making the noise ridiculous. THat's why everyone is putting Sonore/SoTM/Aurilic, etc. (quieter mini-Linux-music-processing-computers) on their audio rack and moving their computers to Cleveland. 

 

All the above being said, - I have a certain amount of experience with certain aspects of all the stuff that I hear, and endeavor to keep an open mind. I wish that I could try stuff like i used to be able to do in the mid 2000s when there were things like a CES. So many people that i respect on here, respect you and use your products. So, - if my Universal player/DAC ever dies, - I am hoping that I may get a chance to try HQPlayer: especially if it works outside of Roon.

[Albrecht]

6 minutes ago, R1200CL said:

Can you give at least 3 examples. I like to see DSD 512. But u choose. 
 

Or do you mean we can have a 20 meter usb or HMDI cable ?

 

Or do you say it’s ok to have a PC doing DSD 512 via usb next to your audio system isn’t problematic. 
 

Fell free to include DSD 512 or 1024 over HMDI 😀

ICron USB to TCP/IP converters.

 

Micro/ultra/optical Rendu

 

SotM SMS 200 series...

 

Rednet Ravenna

 

Lumin...

 

NAS to Rendu or SoTM series.

 

Gustard, Audiophelio, Berkeley, SingXer, Denafrips, etc USB to i2s converters....

[Albrecht]

2 minutes ago, R1200CL said:

Do you actually know what a Singxer SU-1 is ?

 

I don’t know what a APL is. How old is it ? Does it have filters, or do it only up sample ?

How do you use it ?

"Do you actually know what a Singxer SU-1 is ?"

 

I've had one in my system for more than 3 years. Currently I use the Gustard U-16 with a Cardas USB cable from my ultra-Rendu... (Debating going to an Audio-GD i20 at 5 times the price, - but not sure). 

 

Sounds GRREAAAAT....  

[Albrecht]

2 minutes ago, R1200CL said:

That is not DSD up sampling devices. We must misunderstand each other. 

Correct, - the job of the DAC....

 

 

[Albrecht]

1 hour ago, Miska said:

 

With modern delta-sigma converters, DSP side plays major part of the performance. The whole idea is to simplify hardware side by moving as much as possible to digital domain processing where you are not restricted similar way as hardware/analog world is. By doing DSP in software using computer you already have, the hardware money can be spent on parts where it really matters instead of putting major part of it into building a resource constrained computer into a DAC.

 

Sorry it took me so long to see this good point. 

 

And to that. I think that it's even more critical to have this occur in the DAC, - such as APL, PS Audio, and (somewhat Chord), are doing..... Instead of relying on external devices, (computer software outside the DAC), - Some of folks use a NAS computer and an endpoint. (I do understand that NAS's are computers, - but is HQPlayer available for a NAS? And, ---- what about those people who have SPDIF 24/192 max receivers/inputs on their (older) DACs. 

For those that are utilizing PSAudio DirectStream products, - the DAC takes any signal and converts it to DSD on the fly, - so you might as well use SPDIF 24/192 as that takes care of everything...  or so their owners believe. 

[Albrecht]

47 minutes ago, 4est said:

What specifically do you mean by this?

APL and PSAudio DACs.

[Albrecht]

1 minute ago, 4est said:

As in DACs that us FPGAs or hardware upsampling?

Yes....

[Albrecht]

16 minutes ago, Miska said:

 

And AKM, or TI/BB chip works soo much better when you bypass it's DSP section and run it straight as plain converter with external processing.

 

But then again you can go for DAC implementation that doesn't have a DSP section. Meitner could be much better for the same price, or much cheaper, if the DSP section is omitted and only D/A section left.

 

 

Those devices have so tiny bit of processing power compared to what you can do with modern CPU + GPU combination. And it is much better done external to the DAC, so not putting the electrically noisy processing near the sensitive analog parts. On hardware side dCS has been doing that for long time and now Chord too with MScaler. But they are still very resource constrained compared to what I can do with something like Core i9-10900K and GeForce RTX2080Ti.

 

So, it is critical to have this happen outside of the DAC and have DAC be just that, bit-perfect digital to analog converter without any processing. Just converting digital samples from input to analog as well as possible. Nothing else.

 

Now I can run the heavy processing in a different room and then the processed data is sent to the DAC over network.

 

 

I just do the same in a computer, in the player application. I can also deal with S/PDIF inputs, or even analog inputs from vinyl and such. And perform digital room correction and such too on the same processing pipeline.

 

Hi,

I see your point. But one definitely needs a DAC that will accept DSD signal as an input. 

 

I guess where I was confused was the difference between DSP and Digital Signal Conversion....???

 

I would love to hear a demonstration of what you're doing vs what is going on in a well implemented DAC that does the conversion there.... (every appropriate DAC is well north of $12K). 

 

Too bad that that is so difficult in these times. And for me to actually buy a new DAC, another PC or MAC server, - (if HQPlayer doesn't run on a NAS), - would be beyond whack right now....

[Albrecht]

16 minutes ago, asdf1000 said:

 

With respect, you posted both of the below comments in the same post, but it's not accurate:

 

"the ONLY reason to ever use HQPlayer in my mind is to get DSD"

 

and

 

"I have no experience with HQ Player. So, - it would be wrong to comment on it in any way."

 

GAAAH...

 

I meant SQ: Of course I didn't actually write that...... i should've specified because I also wrote "in any way," bad on my part.

 

But I also wrote that I respect others who use HQPlayer and I respect Miska for making good arguments......

 

[Albrecht]

 

5 hours ago, R1200CL said:

 

 

 

 

 

 

 

5 hours ago, R1200CL said:

@Albrecht

 I found your DAC

 

 

 

 

 

I have a dream....   ......

 

I wish... and given what I know of APL (reflected in the review) it is a great DAC and likely a very big step up from mine: true SOTA.

Cheers,

 

[Albrecht]

9 hours ago, R1200CL said:

 

I happen also to use a SU-1. (Modified). And it’s not 20 years old 😂. I guess the age was the DAC. It seems we both doesn’t have a DAC with USB interface. Correct ?

I use a Theta Generation Vlll (PCM 24/192 max). 
 

What DAC are you using, and why would you even consider the Audio-GD i20 ?

 

I also use a SonicTransporter with HQPlayer.

If you’re only using PCM, you can probably install HQPlayer in your NAS. At least if it’s a QNAP. Are you using Roon ? And if yes, where is it installed, or what player are you using ?

Hi,

I have been very impressed with Theta DACs that I've heard, - FWIW. 

I have a QNAP NAS that runs either LMS or MiniMServer depending on my mood. I like running LMS for convenience and in our building we have 8 different LMS endpoints/or Squeezebox/squeezebox emulators running: so it's mostly just laziness that I don't flip the ultraRendu to MPD/DLNA. 

But I've found that running MiniMServer via Fiber, to my ultraRendu is a just a little better sound quality.

I just have a 24/192 RCA SPDIF input on my APL Universal player. WHen I want to run-DSD, - I just play SACDs. But the quality of the ultraRendu/Gustard/QNAP is almost as good as playing SACDs on my system. 

 

I am thinking of moving to the Audio-GD because everyone is reporting that the Audio-GD blows away the Gustard. But i do not know exactly how they are applying it. Plus, - would the Audio-GD or upgrading to the opticalRendu be the better call? 

IMO the Gustard is a step up from the Singxer, Audiophelio, Berkeley, etc. 

 

 

Cheers,