Ciúnas Audio ISO DAC Teardown and Failed Review

[Soniclife]

But when you have closely matched or subtly different attributes it doesn't.....in my experience off course.

People are free to use any method they want, as long as it's double blind and level matched. You can listen over weeks, if you want. But people who think this is going to improve their accuracy have so far failed to produce evidence that it works.

 

[Timola]

People are free to use any method they want, as long as it's double blind and level matched. You can listen over weeks, if you want. But people who think this is going to improve their accuracy have so far failed to produce evidence that it works.

There are limits to experiment design and although the scientific principle is the best we have to probe nature in some cases (especially when human feelings are involved) it may be of no ultimate value. We're getting philosophical now...I'll now go read some...LOL.

 

[March Audio]

Hello guys,

I discovered this thread from the brief posting of a link on the PFM forum. It's been a very interesting read as I have owned an ISO-DAC for over a year now and having just read the review by TNT audio on the Cuinas website, I find myself agreeing with almost every word of it.

John Kenny ran a 'Dac Tour' thread on PFM last year and out of curiosity and his generous offer of a free listen, I joined it. I was very impressed by the ISO-DAC and quickly purchased one. I have to say it's the best DAC I've had in my system compared to my previous DACs; Audiolab MDAC and the Linn DSM. I have to agree with TNT audio, the ISO-DAC sounds almost vinyl-like, certainly doesn't have the usual digital signature. I had no idea what was in the unit (until now) or what filtering it uses, all I know is that I really enjoy listening to it. Digital always fatigued me before the ISO-DAC and without knowing it I would drift off to do something else, but with the ISO-DAC the opposite is true.

I posted my review (see below - copied from PFM, ) on the DAC Tour thread on PFM in July 2018 and I would stand by it even more so now. BTW I'm no professional reviewer or anybody with 'golden ears', I've just been listening to HiFi and attending shows all my life (55 now). IMHO: the best vinyl set-ups (LP12) trump any digital set-up (although the DCS Vivaldi gets close).

The ISO-DAC has a quirk: getting Windows10 to pick it up can take a few attempts, but once it has I just leave it permanently on and plugged in. Mine's now been plugged in and 'on' for several months and I've had no problems (I do have smoke detectors in my listening room, now that Amirm has worried me). John Kenny told me those batteries are good for many years (9 if I recall correctly was the oldest set he still has working).

I initially found Amirm's teardown rather distressing as seeing the internals for the first time, they do look rather shocking. But having digested this thread for a day or so and knowing what I know about the ISO-DAC, I take a positive from this thread. Whatever John Kenny has discovered with the ISO-DAC design, there appears to be an opportunity to improve it even further (an exciting thought) by designing a dedicated high quality PCB and wiring layout to really capitalize on his discovery.

Just my thoughts.

Here is my review copied from PFM first published in July 2018. Remember I'm just a regular guy who likes to play his HiFi loud. (I was on a temporary ban from PFM at the time so John Kenny posted it for me).

Here's timolo's listening impressions that he asked me to post:


Hi everyone, I received the ISO-DAC, a PSU (no mains lead supplied so I used one of my own), a USB cable and a 4mm Jack adaptor cable. I didn't need any of these bundled cables, I simply took my MDAC out of my system and replaced it with the ISO-DAC.

My system consists of:: a Laptop (ASUS Zenbook with 4TB portable USB drive containing my music files which are mostly FLAC) running Windows10 loaded with Foobar2000(DarkOne skin) controlled by an IPAD running the MonkeyMote App. I sit in my listening position controlling things from my IPAD. The laptop is connected via a 5M Audioquest USB cable to an MDAC (powered by the MCRU regulated linear PSU) which goes to my Linn Aktiv crossover which then connects to 2x3 LK280 Poweramps running Linn Isobarik speakers,

When I got the ISO-DAC, I connected it and got it working through Foobar and was immediately impressed I felt it was better than the MDAC. Just to confirm I plugged the MDAC back in and quickly confirmed the ISO-DAC was easily better. I didn’t have much time, so I took a couple of pics of the set-up and sent them to John Kenny. I got a reply back that I was using the wrong drivers in Foobar and needed to download some W10 drivers which he linked to an that I should be using a shorter USB cable. Since I have Amazon Prime I ordered a 1.5M Audioquest Forrest USB A-B cable to arrive next day (ish).

The cable arrived, I downloaded the W10 drivers (ASIO: Combo384 ASIO 1.03) and hooked the ISO-DAC back in. I spent nearly four hours listening to lots of my favourite tracks and became more and more convinced that I can't send the ISO-DAC back to JK. I started working out if I could afford it, because I'm in a tricky situation; I'm heavily invested in the LakeWest MDAC2 project which is promising a new DAC later this year which will set me back around £1.5K plus DeTox and Dev Fees.

Music used (FLAC):
Camel-Nude_Drafted 857Kbps 44KHz,
Camel-Nod and a Wink_Simple Pleasures 783Kbps 44KHz
London Grammar_Metal and Dust 1454Kbps 44KHz
Santana_Veracruz 2914Kbps 96KHz
Santana_Aqua Marine 2854Kbps 96KHz
Amy Winehouse-Back to Black_Love is a Losing Game 2742Kbps 96KHz
Kraftwerk_The Robots 1467Kbps 44KHz
Pink_What About Us 1609Kbps 44KHz
Pumarosa-Witch_Priestess 3044Kbps 96KHz
Fleetwood Mac-Dreams 24bit/96
Vangelis-MASK and Soil Festivities 16bit/44

I found the ISO-DAC sounded brilliant, the bass was much deeper/fuller with different bass guitars notes, nicely distinguished and defined. Drum kits on Camel, Santana, Fleetwood Mac very nicely rendered and tight. The vocals were superb, open and clear. The top-end initially sounded a bit muted, but I'm now sure that's because I had become accustomed to the rather thinner and glary top end on the MDAC, I played some Vangelis and Santana (Veracruz) that I know have lots of high bells and cymbals and it was all there with the ISO-DAC only without the glare or ringing I was used to. The ISO-DAC sounds to me more like a top TT set-up without that Digital harshness in the sound signature that always annoyed me.

Issues I have, which I'm very comfortable overlooking as this ISO-DAC sounds so good (and is so keenly priced) are:

It doesn't have any other inputs (except USB) so I can't connect my TV optical output to it.
If you power the ISO-DAC off/on while the amps are on there is a loud click (I simply turn on/off the amps first then the ISO-DAC, problem solved).
The blue power LED is too bright for my liking, but the unit is so small, I simply turn it slightly away from my line sight (as I listen mostly in the dark) and the problem is solved.
The volume slider on my MonkeyMote app is annoyingly small, I'm now looking for a better way to play music and might try Volumio or something similar (any recommendations would be well appreciated). This of course has nothing to do with the ISO-DAC.

I wondered why the ISO-DAC so easily out-performed the MDAC and my conclusion was its inky blackness in the sound, by which I mean each instrument/voice just hangs there without any background, sounding clearer and distinguished at all volume levels. So I looked up what Ciunas means (Silence/Stillness from old Irish) and that explained it to me, it was the quietness of the power and the design in the ISO-DAC that was the key. A clear triumph for the designer JK. It also explains JK's confidence is letting anybody try it out completely free for 30days. If you're not on this DAC-TOUR, I highly recommend you join, this could be a revelation. For me it was, the MDAC has been holding back my system for years. When I initially bought the MDAC (4 years ago) I really loved it and had a few bake-offs with the Linn Akurate DSM and a Meriidian CDplayer and the MDAC held up well in comparison to the £4K Linn DSM which made me feel great and my mate a little upset. But I can now confirm the ISO-DAC sounds better while not having the inputs and volume control/inputs of a pre-amp which I thought I needed but now feel I won't miss because of the extra enjoyment I will get from the ISO-DAC sound.

I would whole heartedly recommend the ISO-DAC to everyone on PFM to buy or at least go for a demo (at no cost but your time), I'm now going to buy one despite waiting for the LakeWest MDAC2 as it's so much better than the original MDAC that I have been using. I can justify its cost even if the MDAC2 eventually betters the ISO-DAC as I'll be happy to have it in another system and simply sell on my original MDAC.

Congratulations John Kenny, a really ground breaking design!

I would so love to comment on all this but it would be inappropriate.......

.... Oh hell why not.

I too have had run ins with JK in the past. I can assure you his electronics competence is non existent. Knowing this I was still shocked at what I see here.

This product is utter trash and dangerous to boot. It and JK deserves to be exposed for what it is. People are being ripped off.

It doesn't sound better. You are mistaken.

Btw when are you going to realise John Westlake has also ripped you off. He has been designing that MDAC2 for what 6 years or more. You will never get anything delivered.

Someone should repost on pink fish

 

[AndrovichIV]

Just to add. Doing 'double blind' listening tests in HiFi is very difficult (almost impossible) particularly at home. Also I believe (just a guess) that it takes a fair bit of time to adjust to the sonic signature of a product and unless the difference is glaring obvious it may take weeks.

Also on measurements, I remember reading a HiFi article on the Linn Isobaric speakers back in the 70's where the measurements were really awful and in fact Linn complained and someone re-did the measurements which although better were still poor. But as far as I know they sold very well and still highly regarded by enthusiasts (like me). My point: the final measurement is in the 'eating'.

The 'measurement/experimental repeatability problem' is a serious issue in science. Some estimate upto 50% of all scientific papers may suffer this. Not that I expect an scope or a voltmeter to lie, so this point may not apply on this forum, it was just a general point about holding too closely to scientific literature.

we really should have a FAQ section that we could point to dispel these arguments, because they pop up in every other thread, and they receive the same answer

 

[BDWoody]

we really should have a FAQ section that we could point to dispel these arguments, because they pop up in every other thread, and they receive the same answer

Might take care of a lot of FAQ'n issues...

 

[LTig]

we really should have a FAQ section that we could point to dispel these arguments, because they pop up in every other thread, and they receive the same answer

I second that - strongly. And we need something like a mandatory introduction for new members to read before their first posting. I volunteer to take part in creating this introduction, but I'm not able to invest much time until end of this month.

 

[Killingbeans]

Whatever John Kenny has discovered with the ISO-DAC design, there appears to be an opportunity to improve it even further (an exciting thought) by designing a dedicated high quality PCB and wiring layout to really capitalize on his discovery.

My prediction would be that you'll get sorely disappointed.

With all likelihood, the "almost vinyl-like" sound is a biproduct of the lousy signal routing mixed with the total lack of decoupling capacitors.

A proper PCB would clean some of that up. There's no discovery in this product... only happy ignorance

 

[Timola]

Is it the view of this forum that listening pleasure in humans from HiFi can be objectively measured? It's a very high level function of the brain, and highly subjective. Who's the better artist Gaugan or Giger?

 

[Purité Audio]

Gauguin is nothing special, Titian or Giorgione now you are talking.
Keith

 

[Frank Dernie]

However, this method will work for obvious differences in components. But when you have closely matched or subtly different attributes it doesn't.....in my experience off course. HiFi is eminently subjective particularly above the budget domain and bringing objectivity to it is a noble cause. I guess this is the point of this forum.

I think it works for subtle differences too.
It also begs the question if the difference is so subtle as to be not noticed on direct level matched comparison is it of any consequence whatsoever in listening to music at home for pleasure?
I would contend not.

 

[BDWoody]

Is it the view of this forum that listening pleasure in humans from HiFi can be objectively measured? It's a very high level function of the brain, and highly subjective. Who's the better artist Gaugan or Giger?

Of course not.
What can be measured is the accuracy (fidelity) of the recreated electrical signal as it moves along the path. Comparing the original signal to the recreated signal will tell you to the current limits of analyzing equipment how closely they match. If they match beyond a certain point, they are audibly indistinguishable.

By your analogy it would be like comparing the art based on what shoes the artists were wearing, or maybe what kind of wood their color palette was made of, rather than the relative genius of the artist.

The music is art.
The electrical signal chain is engineering.

 

[Eirikur]

Is it the view of this forum that listening pleasure in humans from HiFi can be objectively measured? It's a very high level function of the brain, and highly subjective. Who's the better artist Gaugan or Giger?

Whom do you consider to be the artist when you listen to music? The composer+performers or the manufacturer of your DAC?
In my opinion you're asking these questions in the wrong context. The DAC is (supposed to be) a precision instrument to reliably, repeatably and correctly translate the digital input signal data into line level voltage. Artistic interpretation doesn't factor into it, only technical prowess.

Suppose you have a hammer with a marvelously carved handle, but that handle hurts your hand whenever you drive a nail. Wouldn't you replace it with a more suitable tool?

 

[Xulonn]

Very well said, @BDWoody.

Actually, neuroscientists can indeed measure pleasure by watching what the brain does with various stimuli. Although the reaction to artistic stimuli is indeed subjective, It is still based on a set of electrical signals scurrying about in the neurons of the human nervous system. No audiophile or audio engineer that I am aware of cares about measuring the physics of pleasure by monitoring or scanning the brain, because that is the domain of medical scientists who are curious about how the brain and nervous system work.

I know when I am enjoying something, but I am also intelligent and aware enough to know that the complex workings of human brain with respect to subconscious sensory input processing can make me think I hear things that are not actually present in the acoustic waves that strike my tympanic membranes.

And that leads to one of the biggest sources of controversy, conflict and nastiness here at ASR. We get many visitors, mostly males, with a range of ego issues from reasonable and adaptable up to virulent rejection of anything that challenges their subjective beliefs. And that last group absolutely cannot admit that they might be wrong in their "perceptions."

 

[Killingbeans]

Is it the view of this forum that listening pleasure in humans from HiFi can be objectively measured?

No, but everything between the studio microphone and your eardrums can.

 

[Labjr]

To even think that someone should be objective while listening and possibly consider buying that POS is pathetic! Would you buy a sports car that looked that hideous under the hood?

 

[Killingbeans]

More like a sport car that's held together with bubble gum and hot glue. No matter how fun it is to drive, I wouldn't touch it with a ten foot pole

 

[Xulonn]

The musicians are the artists, but the recording and mastering engineers also contribute to the "art" of the recording.

DAC design by a competent, well educated and trained electrical engineer whose goal is to preserve signal integrity and accuracy has nothing to do with "musicality" - unless they are foolishly trying to "color" or "flavor" the music at that "decoding" stage - which is apparently what some boutique designers actually do.

How many times (248,000?) do we have to repeat the reality that the best way - to either correct or alter the electrical signal of the recording - is via room selection and treatment, or by using DSP for "room correction" with feedback from a microphone(s) at the listening position?

Good acoustics to minimize unwanted sonic coloration begins in the studio and ends in your listening room. Here's a link to how recording studios might attack the problem...

https://www.musictech.net/guides/essential-guide/sonic-perfection-a-guide-to-room-calibration/

 

[Labjr]

More like a sport car that's held together with bubble gum and hot glue. No matter how fun it is to drive, I wouldn't touch it with a ten foot pole

Well...maybe if it was JB Weld.

 

[BDWoody]

More like a sport car that's held together with bubble gum and hot glue. No matter how fun it is to drive, I wouldn't touch it with a ten foot pole

Sounds like my FrankenVolvo I built out of three vehicles back in the day...
It caught on fire a couple times because I didn't route a battery cable very well, then because of a fuel leak from those damned twin SU carbs that I could never get to balance out right...
I won't even mention the clutch pedal bracket I welded in (original was an automatic) that broke a few times while driving, until I learned to weld a little better...
Anyway...yes... Wasn't a sports car, but bubble gum and duct tape were definitely strategically used...
Hot glue was for the rich kids... Keeping distance would have been most wise.

Edit: But it had a great stereo, worth a lot more than the car...

 

[LTig]

Sounds like my FrankenVolvo I built out of three vehicles back in the day...
It caught on fire a couple times because I didn't route a battery cable very well, then because of a fuel leak from those damned twin SU carbs that I could never get to balance out right...
I won't even mention the clutch pedal bracket I welded in (original was an automatic) that broke a few times while driving, until I learned to weld a little better...
Anyway...yes... Wasn't a sports car, but bubble gum and duct tape were definitely strategically used...
Hot glue was for the rich kids... Keeping distance would have been most wise.

Edit: But it had a great stereo, worth a lot more than the car...

I'm glad you're still here ...