OK, apart from a very pleasant round of golf on Sunday morning followed by a family catch up, I have been using the long weekend to fool around with different scenarios feeding the Arche from my iMac using Audirvana with the exclusive mode setting and also comparing to a Chord Qutest/Topping A90 combo. I used both my Focal Clears and Hifiman Anandas for testing as well as a Cardas Clear USB cable and a Lifatec glass Toslink cable. A Topping D10S was used as a USB to SPDIF converter with Toslink. I'll preface my findings by clarifying that I do not have golden ears, I suck at describing differences in sound and any thoughts or preferences are purely subjective using
my ears.....not yours
Focal Arche USB input vs Toslink
Based on historical issues with USB when I first got into digital audio, I've pretty much avoided it and use 100% SPDIF in my main speaker setup with an Allo Digione Signature streamer and digital room correction. That stance is probably very narrow minded today with USB implementations having come a long way with improvements such as galvanic isolation etc. now standard in most DACs. Interestingly, I can't find anything from Focal that indicates that the USB connection is galvanically isolated? I would be staggered if it's not given that much much cheaper DACs are but I guess you never know.
Both mediums have potential advantages and disadvantages over each other and a lot depends on the actual implementation of the equipment used:
USB:
- Much higher bit depth & sample rates
- Simple option for computer playback
- Low jitter potential
- Potential for electrical noise and ground loops
Toslink
- Limited bit depth & sample rates (24/192 in my setup and I don't need more than that)
- USB to SPDIF converter needed in most computer setups
- Increased jitter (It is debatable whether this will actually be in the audible range based on nearly every measurement I've seen in modern delta sigma DACs)
- Complete electrical isolation from the source
So, now on to the listening and you are going to be disappointed as it's far from conclusive. I used the hybrid amp setting exclusively and I made sure that the Arche USB connection was unplugged when using Toslink. I did both quick comparisons on single tracks and more sustained listening comparisons of 45 minutes or more. There were no typical Audiophool moments such as "veil lifting", "details I've never heard before" and "massively increased soundstage". The main difference was that USB always
seemed a touch louder in my sighted testing? Was it adding something or was Toslink taking something away? Probably a moot point as my son was over on Saturday and neither of us did very well in picking one over the other in blind testing. I guess my one subjective takeaway from all of this is that I got the impression that I could listen longer without any hint of fatigue using Toslink but that could be attributed to all sorts of other factors to do with my mood, tiredness etc at the time. I guess the main thing is that I see no downside to using Toslink over USB if you need the added isolation benefit.
Focal Arche vs Chord Qutest/Topping A90 combo
I will start by admitting that I am a linear power supply junkie, ever since I replaced a particular wall wart in my main setup years ago and heard an immediate improvement, I have avoided cheap switching power supplies in my setups. This is probably overkill as I am not naive enough to think that
all switching power supplies are detrimental to SQ but I err on the side of caution. In fact in a recent test I did, I had trouble finding any SQ differences with the Chord Qutest in my speaker setup feeding my MF M6 500i integrated amp and switching between the supplied wall wart and an SBooster LPS. Yes I thought the LPS
might be better but it wasn't "night & day".This debate often rages in the Qutest thread here and Rob Watts is adamant that an LPS is unlikely to make a major difference and in fact could be detrimental to SQ. So from a logistical perspective, I set up the Qutest feeding the A90 in my desktop headphone setup with the wall wart powering it as I didn't want the bulky SBooster cluttering up my desk.
I won't go into details here other than to mimic some other impressions that you've probably read elsewhere, these were two completely different presentations with the Arche displaying it's AKM + class A amp nice wet mid bass compared to the tighter, analytical nature of the A90. The Qutest/A90 combo had the blackest of backgrounds, superior instrument separation etc but for both short & long term listening enjoyment the Arche was a winner.
Then for giggles, I lugged over the SBooster and replaced the wall wart on the Qutest. This changed everything - the Qutest/A90 combo still maintained it's redeeming features but was now much more relaxed and enjoyable with no hint of any harshness. This was perplexing, perhaps just a synergy thing or the fact that listening through headphones makes a major difference? Who knows? Who cares?
Now this was a much more interesting comparison and it honestly came down to a flavour preference with both setups shining on different genres and masterings. From a personal perspective I sometimes preferred the wonderful separation and detail retrieval of the Qutest/A90 and (in comparison) sometimes the unassuming "organic" fuller presentation of the Arche. The only point I will make here is that whilst the AKM DAC in the Arche has that nice signature mid bass bloom that AKM describes as their "velvet" sound, I find the upper mids and highs to be sometimes a little edgy compared to the Qutest. Also, the Qutest/A90 combo had the ability to provide "wow" moments on certain material. For example, playing the Hollies -
Long Tall Woman in a Black Dress was amazing on my Anandas plugged into the A90 compared to the Arche, and this included running the Qutest into the Arche amp. With all those different guitar solos I felt like I could hear those fingers/plectrums doing their plucking and the separation between notes was superb.
That's enough rambling and my apologies for going off topic. I think the biggest takeaway for me has been the importance of system synergy when assessing individual
components. So which setup will stay on my desk? The answer for now is both of them, I really need more time to make sure. I really like the one box solution of the Arche over the separate components but it does have the occasional flakey moment, so let's see. I have more than one pair of headphones that compliment each other so I'll do the same for DACs & amps for the time being - I just need to do a bit of rearranging.
