Tír Na HiFi

New king of the heap USB card on Big7 trumps the rest.
http://www.diyinhk.com/shop/audio-kits/ ... d-pcb.html

2 x 3.3v supplies required and its got isolation as well.
Sounds great when powered by the Low Noise Linear PS linked below or 2 Lipo batteries.
http://www.diyinhk.com/shop/audio-kits/ ... 15ax2.html

The downside with the Power Supply is that it is supplied in kit form and you have to solder it all together but worth it as you get 2 x clean 3.3v low noise supplies on the one board.

You have to provide 2 x 6.3v AC in so I got an AnTek transformer which worked out perfect, a bit over spec but works great.
http://www.ebay.co.uk/itm/252435799440? ... EBIDX%3AIT

You really notice that you listen at higher volume after listening to this card as it is so natural and clean you have no edge or fatigue listening at volume.
The lower bass opens up even more compared to the other cards I tried.

For the cost the best upgrade so far for the Big7.

Card Below


Card and Power Supply Below


Transformer Below


Full layout to I2s Below


Collection of USB cards used previously Below

wouldn't have thought the isolator would make so much difference
reclocker should be a dead cert for another lift, if i remember right the 768's pinout will allow for short wire to a 574 chip it could be a pretty neat solution and could be powered from the same ps as the clean side of the isolator

nige2000 wrote:wouldn't have thought the isolator would make so much difference

Seems the more isolation the greater the benefits, still have the Intona in the chain as well.
Listening to a hirez pcm album at 24 88 from Beck called Sea Change last night and it was amazing all the extra cues and effects coming through with this card, still amazed at the added bass power and control which I have never heard before.

Will touch base with you at the weekend how to add the reclocker.
I tried one on the Amanero and did not notice much of a difference but I could be doing it wrong!

Sligolad wrote:

nige2000 wrote:wouldn't have thought the isolator would make so much difference

Seems the more isolation the greater the benefits, still have the Intona in the chain as well.
Listening to a hirez pcm album at 24 88 from Beck called Sea Change last night and it was amazing all the extra cues and effects coming through with this card, still amazed at the added bass power and control which I have never heard before.

Will touch base with you at the weekend how to add the reclocker.
I tried one on the Amanero and did not notice much of a difference but I could be doing it wrong!

I believe that there is something else going on here that is improving the sound quality. In my experience isolation on digital signals is a mixed bag - where the isolation is applied is important - the closer, in the signal chain, to the source, the better but this is also not cut & dried - when you isolate at the USB transmitter, noise can be added as the signal passes through the various stages downstream

Further to this all isolation seems to add jitter/noise to digital signals so a reclocker after isolation improves the sound

The NDK clocks might be responsible for the batter sound rather than the isolation - you may have lucked out & got good ones on that board. As reported by an RF engineer who measures these NDK clocks, there is great variation in the quality of a reel of these clocks - some are great & some not so good - don't know what is the statistical breakdown into these categories?

actually i ordered a couple of 574's this morning for you to try reclocking on it sat if we get time, ill stick one on a board before then for easy assembly

the few times i experimented with isolation on i2s were always with batteries
first shock was that isolation of gnd had no benefit
i tested by connecting gnd each side of the isolator in a b testing
therefore gnd isolation isnt everything?
which is kinda weird as gnd is usually the thorn in the side

if you look at most data sheets of isolators they will have an induced jitter figure
put simply the signal has more jitter coming out of the isolator than it had going in

i know on the soekris bypassing the i2s isolators made for a cleaner more resolving sound

my conclusion was that if isolators were having benefit it would be because of a noise problem which needs to be addressed anyhow

My reasons for thinking Isolation were based on the difference between the same XMOS 768 board with and without Isolation, there does not appear to be any other significant difference between both products.
The XMOS 768 without isolation i had running with a 3.3v Lipo and compared to the new XMOS 768 with isolation which requires 2 x 3.3v which I also ran with 2 separate 3.3v Lipos, the new board even when run off the linear PS sounds amazing and is improving.

You would not think there could be much noise getting to the USB card given my chain is as follows and has been for some months:

JCat USB card with PCIe 3.3v disconected and separtate Linear 3.3v supply.
The JCat has the Linear 5v Molex feed taken off the Paul Hynes supply.
PPA Red USB to Intona so the Intona gets clean 5v from PH supply.
Out of the Intona I have a Supra USB cable with the 5v pins blocked off and this goes to your Lipo powered Regen John (will sort you out at the weekend on that, months of great sound) :-))
Out of the battery powered Regen another Supra with 5v blocked and this goes to the XMOS 768.

I would have thought from the above that Isolation would have been well sorted as the 5v side is well stopped back in the chain and it is only the Data side that is getting to the USB Card, maybe it does not make any difference having additional isolation on the XMOS 768 and that there is something else going on.

Either way I am seriously impressed with the improvements that these additions have made to the Big7 and my listening enjoyment.

Look forward to trying a reclocker Nige and I have a chip myself that I can use if you do not get any by the weekend, will run the wiring by you anyway to make sure I have it right.
Thanks Guys.

Sligolad wrote:My reasons for thinking Isolation were based on the difference between the same XMOS 768 board with and without Isolation, there does not appear to be any other significant difference between both products.
The XMOS 768 without isolation i had running with a 3.3v Lipo and compared to the new XMOS 768 with isolation which requires 2 x 3.3v which I also ran with 2 separate 3.3v Lipos, the new board even when run off the linear PS sounds amazing and is improving.

You would not think there could be much noise getting to the USB card given my chain is as follows and has been for some months:

JCat USB card with PCIe 3.3v disconected and separtate Linear 3.3v supply.
The JCat has the Linear 5v Molex feed taken off the Paul Hynes supply.
PPA Red USB to Intona so the Intona gets clean 5v from PH supply.
Out of the Intona I have a Supra USB cable with the 5v pins blocked off and this goes to your Lipo powered Regen John (will sort you out at the weekend on that, months of great sound) :-))
Out of the battery powered Regen another Supra with 5v blocked and this goes to the XMOS 768.

I would have thought from the above that Isolation would have been well sorted as the 5v side is well stopped back in the chain and it is only the Data side that is getting to the USB Card, maybe it does not make any difference having additional isolation on the XMOS 768 and that there is something else going on.

Either way I am seriously impressed with the improvements that these additions have made to the Big7 and my listening enjoyment.

Look forward to trying a reclocker Nige and I have a chip myself that I can use if you do not get any by the weekend, will run the wiring by you anyway to make sure I have it right.
Thanks Guys.

Yea, Pearse - a lot of isolation & noise blocking gizmos in your signal chain - I'm just wondering if the number of mains connected PS supplies along the chain might also be introducing ground loops which are somehow bypassing these isolation steps - remember the mains is another loop pathway. I'm wondering about the PH powering the Intona - have you tried a 5V battery instead?

Oh, yes the Regen - I'd forgotten you had it - I was searching through my stuff looking for it to bring with me to Nige's. Will you bring it & the Intona to compare to my ISOHUB?

Hi John,

Do not have a 5v battery at the moment but will bring all the gear tomorrow and we can try the Isohub instead.
Could be a very busy day but looking forward to it....I think a pen and notepad may be needed!!

Cheers, Pearse.

Sligolad wrote:Hi John,

Do not have a 5v battery at the moment but will bring all the gear tomorrow and we can try the Isohub instead.
Could be a very busy day but looking forward to it....I think a pen and notepad may be needed!!

Cheers, Pearse.

I thought you had an Anker battery pack or two, no?

ill see if i can find my anker

take it the intona wouldnt like a dose of 6.6v?