High resolution digital is dead. The best DAC's killed it.


Something that came as a surprise to me is how good DAC's have gotten over the past 5-10 years.

Before then, there was a consistent, marked improvement going from Redbook (44.1/16) to 96/24 or higher.

The modern DAC, the best of them, no longer do this. The Redbook playback is so good high resolution is almost not needed. Anyone else notice this?
erik_squires
I’m just starting to learn this now. My new MHDT Orchid sounds amazing streaming Redbook. 

I think digital has sounded great for a long time.  Loved my system way back when I used to use my Meridian 508.20 CDP.  Still sounds great using a benchmark DAC and streaming.
@gosta  

All local files and streams including Tidal, etc. are first converted to DSD 512 on my server PC before heading to my Windows 10 streamer and finally through the DAC 8 DSD chipless converter.  As long as you have server horsepower, you can even use DSP while doing this, which is fantastic to tame a bass mode or to use as a balance control.

The PCM side of the DAC is ok, but once you hear DSD 512 there's no going back.  There's more texture, better tone, soundstage expands in every direction, imaging is more precise AND has more density (that is the hardest trick to pull off IMO).  It really is something.
@orpheus10

The difference in sound quality, if any, is going to be highly gear dependent.

However, converting FLAC and ALAC to WAV is super easy, and bit perfect.

Best,

E


Hi-rez is dead for me because you can only get FLAC, and I prefer WAV; however, I am very much interested in DAC's and CD transports.
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I'm looking forward to Steve Huffman or Stereophile stealing this thread as an article idea, again.
I couldn’t agree more with the OP. The desire for high-res was to reduce the timing artifacts from older DACs.

I have the latest Beresford Caiman SEG DAC which is optimised to more accurately convert an SPDIF clock signal. The stability on Redbook is incredible. Standard Redbook choral music (Thalis Scholars) exhibits only natural harmonics and none of the harmonic timing artifacts that I’d previously assumed were on the recording.

High-res was a temporary workaround.
There are 3 models of Kassandra DACs, between about $25k and $90K.  Which one did you choose?  
Interesting thread. I found my destination digital with the Aries Cerat Kassandra DAC. No up sampling, no filter, and using 16 x AD1865 NK chips. Huge power supplies, tube out (10v) I/V transformers, and huge output transformers. It weights 67 kilos but soundly beats all others I had at home inc:

Hilo interesante. Encontré mi destino digital con el DAC de Aries Cerat Kassandra. Sin muestreo, sin filtro y usando 16 chips AD1865 NK. Enormes fuentes de alimentación, transformadores I / V de salida de tubo (10 v) y enormes transformadores de salida. Pesa 67 kilos, pero supera a todos los demás que tenía en casa: 

1. Ch Precision C1
2. Chord DAVE
3. Lampizator Golden Gate
4. Naim CD555
5. Audio Note DAC 5 Signature

Check out:
https://ariesceratespana.com

so what’s your point?

Take a pill sunshine. I said That the DS PRO PRIME was part of the "DS Pro" series and it was the only one of 9 in that series that was Delta Sigma, the rest all being R2R.

I don’t know what gen Cassanova i was holding

And that the Casanova was also Delta Sigma, it states it in the manual specs and online, here is the page https://ibb.co/zf4T5Xp
You must have been holding on to something else too tight.

George:
02-15-2019 3:23pm
And all the DSPro’s from Gen 1 were R2R
Sorry, but the Pro prime was only one of the Pro series to be Delta Sigma it used the DS chip SAA7350GP. The Pro Prime II was not DS it had 2 x PCM67P-K R2R chips
read what i wrote, DSPro, not Prime, not Basic, DSPro. regardless, you seem to agree that the DSPros  were R2R, so what's your point?  Maybe I'm missing it...

And the card i was holding had a PCM17XX (i forget) R2R chip on it. Or a BB series that I thought to be R2R (e.g. 17XX, PCMXX) but that was some time back.

Now, as to when PDM/sigma-delta was in wide use (not in labs -- bear in mind that the Theta DSPro G2 is from 1993-4), i recall in 1987-1988 i was looking at the BB PCM54 predecessor to the PCM55 and 64 and it -- and the whole series to come -- was *very new*. BB was  in its R2R days.  Phillips was selling lots of what 1741s or something like that (ancient history!). But R2R was not special - it was simply how most things were done then.
I don't know what gen Cassanova i was holding or what variant - it was a card brought to me bare, with a project in mind. We scuttled that idea after speaking with Theta.
But regardless, my point was that the Theta DSPro was a significantly better performer to the Casanova i was holding, and according to the engineer i spoke with a Theta, the big differences was horsepower to perform the DSPs.  Maybe it was more - i didn't have the time or interest to play twenty questions with someone helping me.... So maybe it was PDM.
And all the DSPro’s from Gen 1 were R2R
Sorry, but the Pro prime was only one of the Pro series to be Delta Sigma it used the DS chip SAA7350GP. The Pro Prime II was not DS it had 2 x PCM67P-K R2R chips


In fact, in 1994 i don’t think there were sigma-delta chips yet
Sorry again, but whatever you want to call it (Delta Sigma, Bitstream, 1 Bit, Mash ect ect ) In 1984, at the Eindhoven AES convention, that Robert Adams of dbx presented a paper on their 1-bit adaptive delta-modulation A/D- and D/A-conversion system.
I had "one" of the first DS based chips in 1990 the Technics SL-PS70

No, is not that simple.The cassanova card (at least the one i was holding) is also R2R.
Sorry again the manual and other sources states it uses for D/A 24bit Delta Sigma dacs and that they are 94khz compatible. Just as the Casablanca does also.
And the A/D section conversion is also Delta Sigma but just 20bit.


I had occasion to speak to the guys at Theta about the Casanova recently. According to them the DSPro is significantly better.
This is also correct, as the DS Pro’s except for the Pro Prime, are all R2R and not DS.

Cheers George
No, is not that simple.The cassanova card (at least the one i was holding) is also R2R. And all the DSPro's from Gen 1 were R2R. In fact, in 1994 i don't think there were sigma-delta chips yet. One of the big changes to the V and 8 was re-clocking (jitter, here we go again)

I was going to avoid the technical details, but it had to do mostly with the DSP power to execute the digital pre-filtering.
G
FYI, I had occasion to speak to the guys at Theta about the Casanova recently. According to them the DSPro is significantly better.
That's because all the 8 "Pro's" (except for the Pro Prime which was DS ) were all R2R and for PCM Redbook it's better, just like what we all expereienced with the two Shanling models in my last post.

Cheers George  
FYI, i had occasion to speak to the guys at Theta about the Casanova recently. I was not terrible familiar.  According to them the DSPro is significantly better.  Casanova is a cool concept withe the all-digital backplane. I considered something like that back in the 1980s. Never took it anywhere for lots of practical and life reasons... mostly i had another company and another job that each demanded my time.
So our experiences may not in fact conflict.

  The Theta Casanova from memory used the same dac chip/s as the Casablanca which had hybrid PCM-1792A converters in it, few bits of R2R and Delta Sigma mix, it was the time of the transition period from expensive to produce R2R converters such as PCM1704 to much cheaper to make Delta Sigma.

Shanling had two identical (earlier 4x transformer model) T100 units, but one used 4 x mono PCM1704 R2R dacs, the other used 2 x stereo PCM1792 hybrid dacs. The we did a/b’s with them and the one with 4 x R2R PCM1704 dac’s was clearly the better sounding unit with redbook.

Cheers George
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First, had a Theta Casanova. WONDERFUL DAC and HT processor.
But .... It sounded a lot better on hi rez than CD.

Modern DACs make it hard to hear the difference I could before. Musically, at 96/24 I might still want the Casanova sound, but at Redbook ......

Best,

E
eric_squires asked:
The modern DAC, the best of them, no longer do this. The Redbook playback is so good high resolution is almost not needed. Anyone else notice this?
Not really. I totally agree that as we solve problems in DACs and in the timing of the signal they are fed, and as recording engineers operate with the systems margins, and as studio formats allow for better filtering, and... (key here - lots of "ands"), we are finding that red book reality is approaching red book theory.

But are today’s DACs, on their own, that much better?  Well, Maybe. I will say that when fed a low-jitter signal, my 20-odd year old Theta DS-Pro (Mike Moffit’s original baby) sounds very, very good. Is it state of the art? No. Is it damn good and better than most modern DACs (which admittedly often cost less?) yes.
Absolute phase is audible but the majority of listeners are unaware of the phenomenon or have heard it and deemed it insignificant, probably the same ones who can't hear cable differences.

Absolute phase is when the leading pressure wave reaches the listener in the same phase as originally produced. Take for example a spoken word like 'push'. The compressive wave launch will reach the listener and drive his eardrums inwards. A reversed phase will create a rarefaction when it reaches the listeners ears and suck them outwards. Think of a kick drum.


Incorrect phase then means the poor listener is using more mental correction effort to try and add realism on top of all the other reproduction issues where the brain has to try make allowances for background noise, distortion and little or no room treatment etc. Absolute phase is often subtle and occasionally astonishing.
I had my CD collection marked to indicate phase. Lots blank (meaning can't tell a difference) some normal phase and some reverse phase. My Wadia DAC has a phase button which I leave to suit the majority and only occasionally change.

@ geoffkait The effect is not system dependant, it is very real and generally impresses when first noticed. What is system dependant is the extent to which it is heard. The battery test you mentioned works to show the direction of woofer travel. The tweeter will not respond via the XO because its series cap will do its job and block DC which is merely academic because the speaker designer, one has to assume, knew what he was doing and designed for proper phase tracking around the XO frequency. It is not necessary to concern yourselves whether the tweeter is in phase or not. Changing both speaker terminals will invert phase to the speaker XO and the tweeter will follow suit.  2,3 or 4- way speakers same story.

@ erik_squires  Richard Vandersteen's big play is for achieving Time coherence
 which is accomplished by physical driver alignment and in the XO and is one of the best values around. Its the end result. Tweeters or midrange drivers may be connected electrically out of phase to place them acoustically inphase. Polarity is chosen for best performance at XO  Think you mentioned full-range drivers, which operate without any XO as such and have their own special sound but introduce other issues. You mentioned 'non R2R DACs' you were impressed with, care to share.

this ought to be great, thanks Malcolm!  Downloaded - would not play in browser. I plan to continue my blog @ sonogyresearch.com with some interesting anecdotes from when i liaised to MPEG while working on both contribution quality digital compressed NTSC and HDTV back around 1989-91.  The findings (which can be informally confirmed with any JPEG compression utility and your phone) are very interesting in a world where compression is a dirty word....spoiler alert - compressed HD > uncompressed SD. No surprise if one considers the degree of redundancy in any HD representation.

G
Lots of interesting points made on a subject destined to run and run. Last year i was privileged to present the AES Heyser Lecture in Milano (May 2018) which included amongst other topics some discussion and personal reflections on sampling rate conversion. You can (hopefully) access the lecture and some related files via the link below including examples of DSD-to-LPCM conversion using a novel "spectral domain" approach to sampling rate conversion. Unfortunately sound quality on the video is a bit compromised due to a technical recording issue beyond my control. Anyway, I hope the content may prove of interest.
https://www.dropbox.com/sh/nqvvwnlh6n6b98z/AAC6kOb5NT8Gk8pceZSbpl2ha?dl=0
M
Sadly, Mark went from making absolutely killer $500 DACs to making even better $25000 DACs. I guess the market spoke, and being smart, he listened :-(
Its also amazing how much better i made the gold full nelson LinkDAC sound by building a custom (dual), custom regulated box. Many, many hours and about $125.00 in parts on ebay.
I cannot hear one whit of difference between 96 and 132k upsampling

G
…But that was a digression from the original topic...but not really.  CDs that are read properly will not be as adulterated by the error correction algorithm that is present in all CD players, so red book CDs can sound truly awesome.  This was the original intention, and between sound retrieval improvements in the source and the processing, we can see how good red book CDs can sound.  Keep in mind, that the operating principle has remained unchanged for decades - but we have better ways of reading, and translating, what has always been there.
Ever since the beginning of (consumer) digital audio, there has been an ongoing debate over DAC's, analog vs. digital, etc. The original design intent for CDs has, over the last several years, been almost realized - a quantum leap over the earlier versions of gear designed to retrieve those elusive bits. One thing that I find has been consistently overlooked is the actual data retrieval itself, BEFORE it gets translated via DAC (or even digital cable leading to the DAC).  I've encountered many products purporting to be the holy grail of CD restoration/ improvement/ enhancement, but one product has stood out: a CD treatment called Essence of Music.  It is a two step process that, in a nutshell, allows the laser to pull out more of the music. This leads to a more accurate reading of the data (improved source quality).  I am not an engineer or a scientist, but I do have more than 40 years' experience in audio, and I am stunned by the difference between treated and untreated discs...and so are other audiophiles when they hear it.  Over the past few years, I have gone to Rocky Mountain Audio Fests with a huge book of CDs...and I deliberately had two identical discs, purchased from Wal-Mart, Target, or even at the shows themselves.  I present an untreated version of the CD, and after 30 - 45 seconds, I ask the exhibitor to exchange the CD, playing the same selection at the same volume.  The looks on everyone's faces (including the exhibitors) tells the whole story.  Through the years, I have tried other products, and even done the 'green marker' thingie, in an attempt to wrest the last bit of music from those silver discs, but this product is the ONLY one that has consistently delivered the goods, year after year.  It is not cheap (what is, in audio these days?), but the difference in sound quality is comparable to upgrading your cables, or amp...you get the idea.  I have even purchased 5 or more copies of the same disc, and found that more treatments yielded even better results.  The change is apparent even on "low-" or "mid-" fi systems - even playing a CD on a BLU RAY disc player.  Try it out - BEFORE upgrading anything else.  You may be pleasantly surprised.
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@emcdade

Would be very interesting if you could give some more details regarding using Roon to upsample to DSD 512 and play back through your T+A DSD Dac. Can you do that with streaming music or only with your own library. New to DSD.
One was the giving-up of R2R DACs. This decoding scheme, despite it’s (potential) errors in switching, is still the best way to convert D to A. High-end makers have been returning to this since 2011 and the results are very welcome.

I won't debate the relative merits of R2R DACs, everything else being equal, but I will say that I've heard a number of non-R2R DACs which show the improvements I'm talking about.

I don't think my central thesis, can be explained this way alone.

Best,

E


Beyond the hype of LP (and new digital formats) what delayed people from finding out how great CD can be were (2) setbacks in digital playback.

One was the giving-up of R2R DACs. This decoding scheme, despite it’s (potential) errors in switching, is still the best way to convert D to A. High-end makers have been returning to this since 2011 and the results are very welcome.

The other unfortunate thing that happened was the switch to hard-disk and SSD sources. The first generation USB standard was a disaster.

All of this has been solved -even if data-connections and converters are still not absolutely perfect. So glad everyone (seems) to be on board !

+1  So true.

Cheers George
There is no surprise in the quality of RBCD these days. Many have known this for 20+ years.

I wrote a piece on CD sound (on Audio Asylum in 2009) called "red book riddle solved". To my surprise, I was nearly laughed out of the barn. Letters to the editor (Robert Harley) proved no better, as he rejected my claims that CD was "all we needed *if* recorded at high-bit and properly dithered"..

What took so long. Well, things drilled into our heads -how good LP was, the "standard", according to Jon Valin and Michael Fremer.

Then confusion. New formats -SACD, DVD-A, now MQA - none were better than CD.

And it was never about "upsampling" either, as the best DACs produced didn’t need or use this.

Beyond the hype of LP (and new digital formats) what delayed people from finding out how great CD can be were (2) setbacks in digital playback.

One was the giving-up of R2R DACs. This decoding scheme, despite it’s (potential) errors in switching, is still the best way to convert D to A. High-end makers have been returning to this since 2011 and the results are very welcome.

The other unfortunate thing that happened was the switch to hard-disk and SSD sources. The first generation USB standard was a disaster.

All of this has been solved -even if data-connections and converters are still not absolutely perfect. So glad everyone (seems) to be on board !



Not only that, but who's to say the CD in your collection from say 1995 wasn't engineering junk? HUGE difference between re-remasters in Return to Forever - Romantic Warrior, Zappa's One Size Fits All, or any obscure George Duke material. Tidal would have the latest work no doubt. It's the ONLY streamer that offers 1400 to date
Can I add something to the mix here...and if the CD kbs rate is 1400, and Tidal is streaming full CD 1400kbs over CELL TOWERS to my phone, and through my Comcast cable to Mac's Tidal app...for $10/month why are we even talking about CDs?

Henceforth, there should be zero difference between whatever 1400kbs signal reaches an audiophile DAC to process. 
@jetter

Or maybe to say it in another way, the woofer and tweeter + and - are attached opposite to the signal from each other?

With 2-way speakers, this is usually the case. The reason has to do with time and crossover phase. It is considered far more important to have them work well through the crossover slope. Stereophile's speaker measurements do a great job of showing this. Look at figure 7 here, and the discussion right above it:

https://www.stereophile.com/content/monitor-audio-silver-8-loudspeaker-measurements

The measurements are typical for a good quality multi-way speaker, like the Monitor Audio line.

You can test any driver you can touch / see with a 1.5 to 9V battery. The + terminal should make the driver move towards the listener when the + of the battery is connected to it, with the negative pole attached to the - battery. 
This may be very difficult with an AMT or ribbon however.

From what I have seen, most speaker makers like to keep the bass in positive polarity, and then invert the other drivers to suit.

Vandersteen and Thiel go through extraordinary efforts to avoid doing this, so they are among the rare exceptions.

Best,

E
Thanks for the clarification.  The only reason I mentioned it is that it would have meant that when replacing drivers I had them not correct.

I have used the battery testing method, but not with a tweeter.  Can you see anything move in or out on a soft dome tweeter to test polarity?
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Jitter, good catch! If speaker drivers are not wired in the same Polarity that would be Big Gnus. 🐂 🐂 🐂 You can hear it right away, I mean, if you can hear. Why would anyone do that intentionally? If it doesn’t make sense it’s not true. JBL did have a woofer wired out of Polarity on some models for quite a while, dunno why. There’s an easy test with a battery across the driver terminals to ensure all drivers are in the same Polarity. Highly recommended. 
Erik "Most multi-way speakers have 1 or more inverted drivers. A typical 2-way box speaker inverts the tweeter relative to the woofer (but not always)."

Sorry, I am being dense here.  Are you saying that the tweeter and woofer are set up to not work in tandem.  That is, when a signal is telling the woofer to play a note (extend out), the same signal would have the tweeter do the opposite? Or maybe to say it in another way, the woofer and tweeter + and - are attached opposite to the signal from each other?
When I used the EAR 324, it had a reverse polarity button that did improve LPs that were clearly reversed.  Stillness, second pressing by Brasil 66 greatly improved with the button pressed in.  First pressing was correct and fuller sounding even after second pressing correction.
Not fair. This is the first time someone has a chance to agree with geoffkait and you want to ruin it. This may be a historic moment.
"So your results are not surprising, glubson."
It seems that erik_squires and you agree on this one.
Most likely the effect is system dependent. So your results are not surprising, glubson.
Regarding "phase inversion button"...

"Um, no one has it because almost no one finds any value in it."
I have it. Two of them. I find it valuable to have them, at least I can say I checked for differences. At the same time, I find difference so minor that it seems to border imagination rather than real result.

In short, if you do not have this magic button, do not despair. You are not missing much.
"Even two sides of an LP could be different (1 side correct, 1 side wrong)."
There is a major conspiracy going on in the world. People have been going out of their way to mess up polarity of the recordings. For decades and all around the world.
fleschler
You are mixing up reverse channels on SP 8 and 10. SP 11 and Ref 3 and 5 have reverse polarity.
Good catch - you're absolutely right! I stand corrected. Thanks for setting the record straight.
I had a Calyx Femto DAC (now sold) that had a phase option with "inverse." I never used it. It was an excellent DAC, but I sold it and bought my current DAC, T + A DAC 8 DSD. It has many options for PCM or DSD with multiple filters and settings. I bought it because it was capable of converting everything to DSD @ 48/512. That's how I listen to all my music with Signalyst HQ Player. I must say I have no experience with most of the DAC's you all speak of. I've only owned 4 all together. As far as I'm concerned this T + A will be the end game for me. I love what I'm hearing and that's my story.
Even if polarity mattered, and I'm on camp no, then what type of gear we need gets complicated.
Most multi-way speakers have 1 or more inverted drivers. A typical 2-way box speaker inverts the tweeter relative to the woofer (but not always).

Things get even more random with 3 or more way crossovers.
So really the only way to have a kind of decent view is to use headphones, single driver speakers, or polarity coincident multi-way speakers, such as the old Thiels, Vandersteens, etc. which have not captured an overwhelming mind share.