TEST: Older R2R Tube DAC vs Newer Delta-Sigma Solid-State DAC

After reading a lot lately about the resurgence of R2R multi-bit DACs, and other strong opinions about one DAC vs another, I decided to do a little experiment, and do a direct AB comparison between two DACs:

1) Wyred4Sound DAC1LE (with Femto clock and other upgrades): Purchased new 3-4 years ago.  MSRP was around $1,300. Uses ESS Sabre 9018 delta-sigma 1-bit DAC chip. Solid state output.

2) Lector Digicode 2.24 (recently serviced and replaced tubes with new Gold Lions). Purchased used (came out around 2002). MSRP was >$5k. Uses 4 Burr Brown PCM1704 multi-bit R2R DAC chips in fully balanced configuration Tubed output.

Both DACs were connected to a Sonos Connect unit feeding a BAT VK-5i preamp, and VK-55SE amp.  I warmed up system for an hour or two, then with each song I played, switched between the two.  I adjusted the volume to match levels.

Result?  Very, very close.  The older Lector unit sounded like it had just a tad more 'air' and a bit more soundstage depth, but I had to listen very closely, and the difference wasn't always that apparent.  There were no other obvious differences that I could detect.

What does this mean?  Well, I don't purport to have golden ears, and have not had my hearing checked, but I have had some 'training' (I was a recording engineer for a while, and was an amateur musician for many years).  I do believe that there are some *very small* differences that I just can't discern very easily, and have to listen quite closely to discern the ones I *think* I can hear!  I do believe that quite a bit of the differences we hear are because we *want* to hear them (not criticizing for this BTW; just my belief).  I was surprised however given the differences in age, topology, architecture, etc. between the two DACs, that I couldn't hear a bigger difference.

By the way, I do understand that some don't believe in the idea of direct AB testing.

What do you guys think?

By the way, source is Deezer 16-Bit / 44.1 kHz ("CD quality") via the Sonos system.  I also listened to some lossy, lower bit-rate music via Pandora.
Not really surprising to me at all. The industry is constantly trying to sell us on the latest greatest thing reporting it to be vastly better than last year's.  About 15 years ago when I was new to this hobby I bought into that but over the years I have come to see it's really not the case, just designed to keep selling the stuff. 
I agree. If you add some RCA old 50’s long plates in the tube amp instead of Gold Lions then you would hear a big difference. The difference between DACs is often grossly exaggerated. Differences there are but they are often subtle.

Comparing 2 DACs from different designers tells you very little.

My experience is that a good Delta-Sigma with minimal digital filtering will sound as good as your best MODERN R2R design.  Older R2R chips like the PCM1704 are not in the running IMO.

You need to compare two designs from the same company.  I designed a tubeDAC, the Spoiler, which was PCM1704 based using Siemens CCA grey-plate tubes for output and I designed a newer Overdrive SX DAC using an Analog Devices Delta-Sigma chip.  The Overdrive is simply better, more detailed, more dynamic and lower noise floor.

Now if I were to compare my Overdrive SX to the top of line TotalDAC or the DaVinci 2, there might be a closer tie.

The other thing to note it the only way to make this comparison fairly is to use the same interface to drive the DAC, usually the S/PDIF coax input, from the same source.

What I enjoy when doing A/B with different DACs is using standard res and higher resolution of the same song with both DACs.  It becomes real apparent which DAC stands out.  

Lower resolutions you will hurt your self trying to hear any major difference...like you said, maybe you want there to be a difference.  Sometimes it’s just one instrument...or one genre...of a certain emptiness between notes.

as already stated, I think your tube analog stage will bloom with some more time and possibly different tubes.  BTW I really like Gold Lion 300B’s...so I have nothing against gold lion.
I agree with the general tenor of this discussion, the differences between DAC chips and topology delta sigma (DS) verses R2R are often exaggerated. There are other factors that are as important or probably more so. Design and implementation of the analog output stage, I/V conversion and certainly power supply quality. Then factor in designer/builder talent and quality of the selected parts. Many important variables to address. Absolutely DS can equal or exceed R2R sound quality. Either can run the spectrum from poor to superb.
I agree; implementation is the biggest issue.  Analog stage and power supplies.

Delta sigma dac chips, as from ESS, are relatively inexpensive as they are produced in great quantity.  Therefore they are used in DACs of all kinds of qualities.  So they are often the subject of criticism by those who think the chip is the thing.  

The ESS chips probably have more R&D behind them than any other and are used in some of  the very best (and expensive) designs.
Was the R2R DAC NOS (non-oversampling)? I think that is what makes the most difference.
Lower resolutions you will hurt your self trying to hear any major difference...

I do not agree.  The right DAC with the right front-end (USB or Ehternet) will make a huge difference even at 44.1.

Steve N.

Empirical Audio

+1!!!  Steve N.
Redbook CD (44.1) with suitable high quality digital components provides excellent resolution/sound quality. Limiting factor has been equipment not the format.

There's a couple of press launch video's of Martin Mallison vice president and chief designer from ESS, in one of the lengthier ones on the design and performance of the top ESS Sabre dac, he apparently says, with this ESS chip we have finally come "close" to the Redbook performance of best R2R Multibit.
Make of that what you will.

Cheers George