Tír Na HiFi

Interesting afternoon at Ciaran's today where we compared two of John's DACs with the mighty dCS stack. I'll just give a few thoughts on todays findings and I'm sure the rest of the lads will chip in later.
Initially there was quite a big difference between the two with all in agreement that the dCS was clearly coming out on top in all areas. To be honest at that stage I was a bit disappointed in both of the dacs that John tried but when he realised that there was a software setting too low and rectified it, the true qualities of the JKDAC shone through. The body and weight to the sound that was so lacking earlier was suddenly there in spades. The gap between the dCS and the JKDacs was now much much closer.

The dCS still edged it I think but not by much. It had a bit more body, weight and ambience to sound yet it was never drawing any attention to itself. No one part of the sprectrum was being emphasised with the dCS. Yet, its important to stress that none of these aspects where a problem with the JKDAC. It sounded very well balanced and a lovely clear sound that sounded great, really good through the Airtights/Kharmas which themselves are very revealing. It was only when switching from the JKDAC to the dCS that you could hear those extra qualities that the dCS brings.

I think its quite an achievement that a computer audio setup can go toe to toe with something like a dCSa and be not too far off performance wise.

I reckon that perhaps with a bit of tweaking on the computer side of things, the drivers, OS and kernal optimisations, etc the gap, small as it is now, might be even closer.

Well guys, after a very interesting afternoon in Ciaran's (thanks Ciaran for organising this), I can report that the dCs system remains top of the list, king of the hill, a-number one. Which is not a surprise really. It had more body, presence & dynamism - more of that elusive being-there illusion.

I will let Ciaran describe/nominate the dCs front-end, amps & speakers. I was using a laptop with Jplay (playback software) & two USB DACs - one with a sabre based DAC chip (JKDAC) & the other (JKDAC32) with an unnamed DAC chip (at the moment :)).. So USB from laptop to DAC & analogue out to Ciaran's preamp.

It was a bit of a shock initially just how big a gap there was between the dCs & my DACs. It took a while but after changing a number of different things I finally realised that I had -6dB of digital attenuation turned on in Jplay. Once I turned off any attenuation the sound improved. Both Fran & Dave thought it a dramatic change - more dynamics, ambience, etc. This brought the JKDAC a lot closer to the presentation of the dCs but the dCs still dug deeper. Interestingly, the JKDAC was preferred to the JKDAC32 which is contrary to the preference of everybody in the past who has heard both. I believe this is because the JKDAC32 was not burned in sufficiently whereas the JKDAC was. Unfortunately, I didn't find the time. Hope this doesn't sound too much of an excuse but the burn-in of these devices really does matter.

When we moved to high res material things got a bit closer, I think (correct me if I'm wrong, guys). I felt the JKDAC at high-res began to pull closer to the dCs but it is/was difficult to compare SACD disk with my download files (I wasn't sure about the provenance of the high res files or even how they arrived on my desktop :) - cough, cough, splutter, ahem ). The dCs certainly has an ability to extract audio cues from 16/44 that make it sound like it's high-res.

Again, many thanks to Ciaran for allowing me this opportunity to hear the dCs front-end in an exemplary system & with good company (thanks Fran, Dave, Simon & cat) in a relaxed environment.

Edit: Cross-post, Dave, thanks! I actually think a week or more of burn-in would do it :)

Which DCS system were you listening to John?

Pity you did not have my burned in unit with you, still it is good to hear your DAC is not far away from ths DCS which i am sure costs several multiples of the cost of the JKDAC32.

Did you feed the DCS using Jplay from PC?

The dCS system consisted of the following 3 units:

Verdi La Scala CD/SACD Transport
Scarlatti DAC
Verona Clock

I'm sure Ciaran will expand on the features/capabilities of each.

Sligolad wrote:Which DCS system were you listening to John?

I'll let Ciaran give the details but I think it was:
Verdi la Scala CDP
Scarlatti DAC
Verona clock

Pity you did not have my burned in unit with you, still it is good to hear your DAC is not far away from ths DCS which i am sure costs several multiples of the cost of the JKDAC32.

Yes, I overestimated the burn-in time & opportunity I had available & a bad back slowed me down also.

Did you feed the DCS using Jplay from PC?

Yes, Jplay from PC using both Hiface driver & Young driver. Interestingly, the Hiface driver was preferred with the JKDAC.

I arrived late to the party, so I missed the earlier comparisons and heard only one track with the 6dB attenuation in place. I'd certainly agree that once that little wrinkle was ironed out the performance of the JKDAC was top-drawer, and while the dCS still reigns supreme, this afternoon blew a few of my preconceptions about computer audio out the window. Ciaran's system is about as resolving as any I know, so any obvious "failings" with the JKDAC would have shown up straightaway. Suffice to say there were no such failings, the DAC more than held its own, was always a pleasure to listen to, and I think I'm going to need to try it at home in the near future! Nice one JK!!

As always, an afternoon spent in Ciaran's listening room was a huge pleasure. Thanks to all concerned, and most especially to Ciaran for having us.

Many thanks to Ciaran; the source, amps, speakers (and that massive kharma sub!) and of course the hospitality were all exemplary.

I'd pretty much concur with what DaveF and jkeny has said - the DCS coming out on top, but the jkeny dacs coming close. It brings a couple of points to mind:

1. The DCS gear/airtight amplification/kharma speakers sounds really good!
2. As a source john's USB dacs came close
3. PC audio now easily matches many high end CDPs (given the performance witnessed today)
4. PC audio is improving at a logarithmic rate
5. Until you hear what's missing, you might not know its missing

Again, a word of thanks to Ciaran for the hospitality.


Fran

The upshot here, is that the likes of the sooloos must be worried.

Yes, two things I'd like to add:
- I recently showed Fran a remote app that runs on an tablet (iOS or Android) & allows full control of the Desktop or laptop running the playback software. It's called Splashdot & essentially recreates your PCs screen on your tablet with full control. So your PC/laptop does not have to be beside your Hifi - it can be out-of-sight & non-intrusive (much like the DACs). The remote control is fabulous with album art, info album notes, etc. & full navigation control.

- I was thinking of having a tour of both DACs & the USB-SPDIF MK3 around forum members to give people a chance to easily hear these in their own systems. If there is any interest, I will set out the details in another thread.

I reckon that some type of embedded system instead of the PC/laptop would take the JKDAC to another level. A board that had the DACs of choice, an FPGA and a small PIC or ARM processor running an RTOS(Real Time Operating System). Also an ethernet port or USB connection for an external hard drive.
Get a good embedded software guy to write highly optimised C code to manage the reading of the data from the disk. This could be then sent out to the FPGA(which also needs a guy to optimise/do) for some number crunching. The FPGA would control the DACs as well as providing glitch free and low jitter clocks to the DACs too. With a serial or JTAG port, both the software and FPGA could be updated in future.

hmmmmmm...strokes chin....

Great stuff guys and appreciation to Ciaran for allowing the comparison. If the JKDAC was best it would be game over so the development continues. As Buzz Lightyear says "to infinity and beyond".
John, what Jplay settings were you using?

KM