1. Things you need to know about the new ‘Conversations’ PM system:

    a) DO NOT REPLY TO THE NOTIFICATION EMAIL! I get them, not the intended recipient. I get a lot of them and I do not want them! It is just a notification, log into the site and reply from there.

    b) To delete old conversations use the ‘Leave conversation’ option. This is just delete by another name.
    Dismiss Notice

DAC tour

Discussion in 'audio' started by Ciunas Audio, Mar 2, 2018.

  1. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    I'm hoping to hear from timolo that he has received the DAC package & a post from beameup on his impressions of the ISO-DAC?
  2. beammeup

    beammeup pfm Member

    My impressions of the ISO-DAC are quite seriously excellent. For anyone that thinks all DACs sound the same, ISO-DAC will readdress those sensibilities and you won't have to go down this endless rabbit hole ever again!

    The highs are excellent with a treble that's best described as (sorry I'm not good at this) very detailed sweet and extended. The sound of a cymbal brush is superb, and the information you from hear a saxophone playing for example is something you just have to listen to for yourself. The music is also very expressive, no holding back here, a trick that's done without being harsh and aggressive. The impact of a drum beat is as immediate and solid as it should be. I'm trying to recall all the impressions I got from this DAC as I type because so much impressed me - for example I remember when a Xylophone was playing and the clarity from this was stunning. John has done a great job of putting together a DAC that conveys the emotion of the music brilliantly. Much better than the Chord Mojo that I also own, and I thought the Chord was good.

    It's well worth a listen now that forum members have a chance while he's passing it about. The proof is in the pudding and not forum squabbles about all DACs sounding the same because they measure perfectly. Give it a go, it's like a breath of fresh air.
    Sloop John B, eastone and Enfield boy like this.
  3. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Thanks Chris for your listening impressions!!
  4. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Timolo is just finished auditioning the ISO-DAC & is very positive about it - unfortunately he can't post here as he is on an enforced break from PFM - maybe I can post his review?

    Martiansunrise is next on the list - can he confirm here or PM that he is ready to audition it early next week?
  5. Martian Sunrise

    Martian Sunrise pfm Member

    Copy that. Ready and willing.
  6. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    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!​
    Sloop John B likes this.
  7. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Just to answer the "issues"
    - yes it's a USB input only as I believe, at the moment, that the best sound can be achieved from this input & I wanted to focus solely on this & optimise it
    - the bright blue switch led is a personal thing - it's simply reduced by changing a resistor - just state this at time of order & lower intensity will be provided
    - there are some volume controllers that sit on the line outputs - I'll try & find them online
    Sloop John B likes this.
  8. beammeup

    beammeup pfm Member

    In my review I missed this very important part out - the lack or glare or ringing - this aspect was very apparent in my system too - I now consider this a very important strength from a digital front end!
  9. argustimewas

    argustimewas pfm Member

    May I ask what external power supply is recommended for the ISO-DAC please?
  10. davidjt

    davidjt pfm Member

    I was starting to wonder why I was the sole enthusiast on pfm.:)

    (Until Beammeup posted, that is.)

    I'm really tempted too, despite being in the JW queue.

    No need to splash out on an after-market psu: the ISO-DAC runs on battery power and a charger comes with it.
  11. argustimewas

    argustimewas pfm Member

    Thank you. It says on the Ciunas website an external PSU is needed?
  12. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    It uses a 5V PS many of these are found around the house & the PS quality is immaterial but for the tour I included a 5V ordinary PS.

    The current output of the 5V PS needs to be considered depending on which ISO device is being powered, & how it is being used. The ISO-HUB uses less power than the ISO-SPDIF ISO-DAC. The ISO-SPDIF & ISO-DAC have the same hub functionality as lSO-HUB.

    If the 5V on the hub is used to power other attached device then this has to be factored into the 5V PS current output needed.

    The user guides specify this & give ebay links to 2Amp or 4Amp 5V output cheap (£15) PSes

    Consider the battery power like a large water tank (a very large capacitor) with a trickle of water entering at the top (the 5V PS) & a large pipe at the bottom of the tank supplying the water demands. It doesn't matter what fluctuations occur in the trickle flow, this doesn't affect the flow of water from the bottom pipe
  13. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Yes, IMO, the etched sound we hear with digital is actually distortion - some people mistake this for the ultra-detail of digital - not so! When all other areas of the reproduction are audibly improved, inner detail, soundstage, air, realism, etc - this etched sound has also disappeared but all the real detail is still there
  14. davidjt

    davidjt pfm Member

    My apologies: since the review one came with a psu I'd assumed that they all do.

    (John - I'd have thought that a basic optional psu would have encouraged more sales.)
  15. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Perhaps but I don't supply an input USB cable, an output USB cable only the USB power cables I already include?
    With my previous non-isolated Ciunas DAC/SPDIF it was possible to charge from a spare USB port but these isolated ISO DAC/SPDIF devices require more than the 500mA limit of USB 2.0 ports so require an external PS (they can be powered from a USB 3.0 port if it actually delivers 1Amp current)

    I reckoned that including a PS would cost the customer more than they could purchase one locally - my packaging & shipping costs would increase

    When people listen to it in their home system they find purchasing a cheap 5V PS locally to be worth the effort - they probably will be buying USB cables anyway!

    I will look again into the feasability of providing a universal mains 5V PS
    Last edited: Jul 30, 2018
  16. krenzler

    krenzler pfm Member

    Don’t you sell a high grade psu already?
  17. clivem2

    clivem2 pfm Member

    The point is that the DAC (and other devices) don't need or benefit from a high quality PS. JK isn't going to be able compete with folks who sell 2A and 4A switching power supplies in volume. The chances are that most of us have suitable power supplies cluttering our home already anyway so leaving that aspect up to the buyer seems eminently suitable.
  18. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Yes but this is designed for powering other audio devices with ultra quiet, isolated power %v & 7V - it's not needed for the ISO devices although it can be used for them.
  19. Ciunas Audio

    Ciunas Audio Trade: Ciunas Audio

    Yes, at £15 for one of these PS, I can't
    That was my thinking - just looking around my own house, I had many 5V PSes & didn't want another one
  20. krenzler

    krenzler pfm Member

    Ah OK, that makes good sense. :)

Share This Page


  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice