[Currawong]

I posted this in the Head Gear section, but I thought I'd add it here. I bought MorbidToaster's Calyx DAC out of curiosity and shameless consumerism and this is what I thought of it.

 

With the nuclear power stations across Japan almost all shut off, our electricity supplier threatened us with deliberate blackouts unless we could keep our usage down sufficiently. Japanese people, being determined, have been bearing the heat, my neighbours all with their aircon off and doors and windows propped open. Since my main listening rig consists mostly of  Class A components with huge, room-heating power supplies, I thought it would be a good opportunity to see if it were possible to cut down the power I need to use when listening to a minimum, without a loss of sound quality.

 

The end result was unexpected -- something that requires another write-up altogether, but part of what ended up happening is that I spotted a Calyx DAC for sale and it caught my eye because it is USB-powered. Needing only 5V instead of 100-120V it would use considerably less power than my main DAC, the Audio-gd Reference 7.1, with its three transformers and heavy power regulation. In addition, Calyx has gained fame with their Femto DAC, which, along with the reputation for audio manufacturers in Korea made their standard offering too good to pass up*.

 

The Calyx DAC is an interesting piece of kit, consisting of a a heavy aluminium block containing, at the rear, a small circuit board with not much more than the minimum required to get balanced output of an 8-channel ES9018 using only USB power, via an XMOS DSP. Plunk it on a desk under a Mac Mini and you have a pretty resolving music system, especially if you use the volume control on the Mac, which works with the Calyx's USB input. The USB input is 32 bit, resulting in fine-grained attenuation down to -127dB, unlike my 24-bit Audiophilleo 1 USB to S/PDIF converter which only goes down to -72dB. 

 

Not surprisingly, the sound quality improves using the separate power supply (looking akin to something pulled out of the back of a computer rather than a hi-fi component, with surprisingly cheap-looking DC cable) or something like the Vaunix lab-grade USB hub. Improving on the very good USB input required me using my Audiophilleo 1 + Pure Power with the coax input. With some back and forth with the Stax SR-009s, focussing on parts of individual tracks, such as the percussion in Waltz for Libby on David Chesky's Club De Sol, while I couldn't make out significantly greater detail, but music in general, typical of the effect of the AP1/PP combo with other DACs, sounded less flat, more 3-dimentional and real with it as the transport. What this amounts to is that it is possible to extract greater things from the DAC through the S/PDIF, but the USB input in the Calyx is the better choice unless you have a high-end converter or transport, such as I do.

 

One of my favourite albums that is very good for testing the performance of DACs is the classic Getz/Gilberto album (think "The Girl from Ipanema"). It both has a considerable degree of detail as well as having some of the most seductive saxophone playing I've ever heard. My benchmark experience of the album was with an Esoteric K-01, where I heard the most incredible micro detail. With the Calyx using the built-in USB for both power and data, there is, to my ears, something of a flatness to the sound, as if the detail is there but the musicality is lacking, not unlike my experience with the Apogee Duet II. Running from the Calyx power supply improved things somewhat, however switching to the AP1/PP as the transport I felt brought out the musicality and emotion of the music. More so, switching to the Vaunix hub as power instead of the Calyx PSU (which was also powering the AP1) there seemed to be yet more, which surprised me, as the Calyx PSU isn't cheap.

 

For use with the SR-009s I prefer using the Metrum Octave, which presents acoustic instruments in a way that sounds more real and less digital. However, with the above-mentioned ancillaries and at what would amount to a total cost double, or close to it, of the DAC itself, I'd extracted a euphoric level of musical expression and no longer felt a need to reconnect the Octave.  Into the Phoenix, with both DACs using the AP1/PP in a daisy-chain configuration**, it was hard to tell it apart from the Reference 7.1. The Calyx sounded very slightly more forward, something akin to a description of how the Sabre DAC sounds in comparison to the old-school PCM1704UK Kingwa gave me, which was that the Sabre makes voices sound "younger". This impression is not one that shows up in quick back-and-forth comparisons, but was apparent listening to a whole track and then switching DACs.

 

While it doesn't have to drive headphones and is somewhat less critical, the output stage of the Calyx uses NE5532 OPAMPs. Those people whom either roll OPAMPs like some people roll tubes or whom are critical of anything without discrete components might thumb their noses at the use of such devices in a high-end DAC, but, at least with what I have, I didn't detect any untoward effects of their presence, unless my impressions of the effect of the Sabre DACs on the sound were actually due to the OPAMPs. However, I couldn't discern even the slighest effect of having both the single-ended outputs in use at the same time as the balanced ones, even if I plugged and unplugged while music was playing.

 

So, overall, though I didn't like it straight out of my computer, since the sound of instruments was rather flat stock, even if everything else about it was excellent. I do like it very with the addition of the Vaunix and AP1+PP. Annoyingly I found one on Audiogon going for only $995 -- a great price and quite a bit less than I paid. I'd say it'll be a great DAC for anyone like me who has gotten into tweaking their computer etc. as a digital source and will try, as I did, to get the most out of it, or someone who wants a "high-end" USB-powered DAC with a relatively small, if not light, form factor.

 

*It's a pity that it would take years to get back the cost of the DAC with power savings, but power being expensive here in Japan would make it more worth it to buy than the Reference 7.1, which, if left on continuously, would use something like $50/month of electricity.

 

**Input 2 of my Reference 7.1 has both BNC and RCA sockets connected together, so I can daisy-chain another DAC from the RCA, which is perfect for either the Metrum or Calyx, if slightly less than ideal due to RCA connections not being 75 Ohm until I can get around to replacing them with WBT jacks.

 

[Currawong]

Reserved.

 

[MorbidToaster]

Glad you liked it (sort of).
 
Also, I totally hadn't seen the one on the Gon either. I kind of feel bad now...I still think you got a good price, but that one's a steal. I will say that his has a scuff and a scratch on it though.

 

[driftingbunnies]

Have you heard the eximus dp1? I'm considering that versus the calyx on audiogon. Lol

 

[MorbidToaster]

He reappears! Glad to see you're considering the Calyx DAC. Hope to see you at a meet soon.
 
Quote:

Have you heard the eximus dp1? I'm considering that versus the calyx on audiogon. Lol

 

[driftingbunnies]

Haha yeah it's been a while. My new years resolution was to not purchase anything audio. I've only started looking again recently

 

[Currawong]

Quote:

Have you heard the eximus dp1? I'm considering that versus the calyx on audiogon. Lol

 
I'll probably take it with me to Tokyo in October where I might be able to compare it. That one interested me as well.

 

[ecapsretliab]

Hello, nice review.
 
Question.  I have a JKSPDIF MK3. 
 
My initial thoughts were dumping the JK when I get the Calyx because it has great USB.  But now seems that might be a bad idea given the sonic benefits.
 
I assume that the XMOS direct to Sabre32 connection is technically superior to the modded Hi-face over coaxial, but for the 5v noise?
 
So should I grab the Vaunix lab-grade USB hub, and a USB cable with separate power/data lines:  http://www.digitalaudioreview.net/2012/07/elijah-audio-isolaate-bl-usb-cable-and-bpm-battery-module/
 
Might this be better than going the whole SPDIF conversion route?
 
What are your thoughts? 
 
Cheers.

 

[Currawong]

It would depend, I guess, on how the JK3 compares to the Audiophilleo + Pure Power.  I think each of the devices improved some aspect or another but it was only the combination of all three that has really nailed it for me.

 

[ecapsretliab]

It would seem the online crowd regards the JK3 in the same league as the A2+PP.
 
I found on 6moons, the reviewer ran the JK3 into the Calyx and was wowed. Better than USB.
 
So I will run CLPS power + JK3.  I doubt I will be disappointed.  I'll save USB power experiments for a rainy day.

 

[ecapsretliab]

Quote:

However, I couldn't discern even the slighest effect of having both the single-ended outputs in use at the same time as the balanced ones, even if I plugged and unplugged while music was playing.

 
Hello again.  I am a little confused, are opamps not used in balanced output?
 
So you are saying you hear no difference between balanced/unbalanced in your experience with the Calyx?
 
You see I have an unbalanced amp.  Given the above, is there any reason to entertain going XLR out > RCA in? (0.5m runs

)   
 
Sorry for being a noob.
 
Thank you.

 

[Currawong]

Quote:

Quote:

However, I couldn't discern even the slighest effect of having both the single-ended outputs in use at the same time as the balanced ones, even if I plugged and unplugged while music was playing.

 
Hello again.  I am a little confused, are opamps not used in balanced output?
 
So you are saying you hear no difference between balanced/unbalanced in your experience with the Calyx?
 
You see I have an unbalanced amp.  Given the above, is there any reason to entertain going XLR out > RCA in? (0.5m runs

)   
 
Sorry for being a noob.
 
Thank you.

 
There are different ways to do single-ended output from a DAC with a fully balanced output stage. One of the ways, which my other DAC uses, involves simply connecting the "hot" pin from the balanced output to the positive on the RCA jacks. That results in a small (though arguably very hard or impossible to notice) degradation of the sound quality, so ideally the DAC should be used with only one output connected at a time. What I was saying above is, I didn't perceive any difference having both XLR and single-ended outputs connected at the same time. I imagine the Calyx uses OPAMPs to create the SE output being the reason for this.

 

[ecapsretliab]

Quote:

 
There are different ways to do single-ended output from a DAC with a fully balanced output stage. One of the ways, which my other DAC uses, involves simply connecting the "hot" pin from the balanced output to the positive on the RCA jacks. That results in a small (though arguably very hard or impossible to notice) degradation of the sound quality, so ideally the DAC should be used with only one output connected at a time. What I was saying above is, I didn't perceive any difference having both XLR and single-ended outputs connected at the same time. I imagine the Calyx uses OPAMPs to create the SE output being the reason for this.

Now I understand.  Thanks for that.
 
Wish I had a balanced setup.  Were you able to run single-ended into your Phoenix for comparisons?  Cheers.

 

[athenaesword]

hi currawong, sonically did you prefer the ref7.1 or the calyx? Also, even though the calyx could be powered solely by USB, it does have the option for external power, did you not consider the lmitations of powering solely through USB as opposed to this?

 

[Currawong]

Comparing both DACs as they stand, I far prefer the Ref 7.1, as the Calyx sound flat and dull in comparison just using USB power from my MacBook Pro. Using the Audiophilleo 1 + Pure Power for both DACs and the Vaunix Hub as power for the Calyx put them pretty close to each other -- that is, I'd need to compare them in a serious speaker rig I reckon to differentiate them.