Interessting, could you elaborate on your experience ? I have ordered one (stx 7.1) and
I was thinking about (maybe) a sparkolabs opamp update for the two chanells on the main board.
You have sold two transformers to a friend of mine (in Sweden Umeå) just a
few days ago so I will get a review from him but the one you are using for the
Asus card might be different so.....
Hi dahlberg,
You can play games or watch TV via internal sound card, yes... But in terms of SQ it is much better to invest money to something really better than to PCI sound card. There is almost no way to fix all the isuues inside the PC. Moreover... I don't know on what step exactly, but defenetely (for my ears at least) something went wrong with PCM179x chips even before any engeneer tried them in his devices. Inspirative measurements but poor sound. At least in the stock version of mine STX - sound is like a piece of plastic. After installing transformers, the sound was much-much better. But I have more really interesting devices where that transformers can be more helpful. Anyway I am using my Asus STX everyday for measuremernts (spdif-out\line-in) and I do not use line or headphone outputs at all in this SC.
Anyway it will be impossible to use Mikael's transformers with PCM179x. There will be no signal between + and - without double primary coils tied to the ground in the center tap.
Regards
You can play games or watch TV via internal sound card, yes... But in terms of SQ it is much better to invest money to something really better than to PCI sound card. There is almost no way to fix all the isuues inside the PC. Moreover... I don't know on what step exactly, but defenetely (for my ears at least) something went wrong with PCM179x chips even before any engeneer tried them in his devices. Inspirative measurements but poor sound. At least in the stock version of mine STX - sound is like a piece of plastic. After installing transformers, the sound was much-much better. But I have more really interesting devices where that transformers can be more helpful. Anyway I am using my Asus STX everyday for measuremernts (spdif-out\line-in) and I do not use line or headphone outputs at all in this SC.
Anyway it will be impossible to use Mikael's transformers with PCM179x. There will be no signal between + and - without double primary coils tied to the ground in the center tap.
Regards
Well I bought the card for multichannel measurents (acourate) mainly. I'm
waiting for the TwistedPear BuffaloIII pro 8-ch dac so in the meantime I figured
I would live with this solution. Reliability and price was a factor as well.
Maybe just as well skip any updates then, thanks for the "review". It will be
interessting to hear what Mikael will say though
waiting for the TwistedPear BuffaloIII pro 8-ch dac so in the meantime I figured
I would live with this solution. Reliability and price was a factor as well.
Maybe just as well skip any updates then, thanks for the "review". It will be
interessting to hear what Mikael will say though
It was a bit of a ritual to get a lock but well there it worked like a charm. I
bought it mainly for measuring purposes and to get something that was
working without any glitches from day one, sort of a soundcard approach. The
measuring process (acourate) with sampling going on and of made it impossible
to use though. Pavel has been most helpful and maybe I just had some bad
luck with this specific bord but I finally lost patience and got a full refund,
thanks Pavel for that by the way. It looks like a really nice build and it
sounded like that as well.
It seems that there was never any problems communicating with the
streamer since it always came up, vu meters (in acourate convolver) and all.
The next step wasn't that unproblematic though. Why, I don't know and I
don't have the time or the knowhow to figure it out.
So for now I bought a "Asus STX 7,1" pci-e soundcard to be able to do some
decent measurements. Maybe somewhere down the line the long awaiteed
"non+ultra, super, duper dac" will be done and then I finally can sit back
and enjoy myself. It sounds fantastic when it's working so I haven't given up
just yet.
bought it mainly for measuring purposes and to get something that was
working without any glitches from day one, sort of a soundcard approach. The
measuring process (acourate) with sampling going on and of made it impossible
to use though. Pavel has been most helpful and maybe I just had some bad
luck with this specific bord but I finally lost patience and got a full refund,
thanks Pavel for that by the way. It looks like a really nice build and it
sounded like that as well.
It seems that there was never any problems communicating with the
streamer since it always came up, vu meters (in acourate convolver) and all.
The next step wasn't that unproblematic though. Why, I don't know and I
don't have the time or the knowhow to figure it out.
So for now I bought a "Asus STX 7,1" pci-e soundcard to be able to do some
decent measurements. Maybe somewhere down the line the long awaiteed
"non+ultra, super, duper dac" will be done and then I finally can sit back
and enjoy myself. It sounds fantastic when it's working so I haven't given up
just yet.
Some news / additions.
After experiments to improve the sound quality of my transformers, it was decided to use the rare vintage wire from the USSR called PELSHO (PESHO). Its more expensive cost compared to modern wire is justified by the quality of the getting sound. Thus, all future transformers will be manufactured using this wire. Now the cost for one pair of transformers will be $150, including delivery.
After experiments to improve the sound quality of my transformers, it was decided to use the rare vintage wire from the USSR called PELSHO (PESHO). Its more expensive cost compared to modern wire is justified by the quality of the getting sound. Thus, all future transformers will be manufactured using this wire. Now the cost for one pair of transformers will be $150, including delivery.
so is one pair is USD 150 plus shipping ,means two units for $150USD ?
Hello everyone who looking for Sound!
After years of expirience the output transformers for current output DACs have been developed. Transformers tested with following DACs: ES9018/28/38, PCM63/58, PCM1702/04, AD1862/65, PCM1792. Speaking in general, transformers can be suited for any current DAC both in SE or PP modes. Transformers for TDA1541 and 1543 in such dimensions - are in process (available but without shielding, even for paralleled up to 8x1543)...
These transformers are made on high permeable cores, have an excellent ratio of the low DC resistance of the primary coil to the inductive resistance to achieve for best frequency response of the DAC. Transformers provides significant sound quality improvement compared to other outputs. Your music will begin to live a new life, it will sparkle with a naturalness without plastic nervousness
View attachment 705304
View attachment 705305
Specification:
Core type - toroidal, core material - nanocrystalline
Can (mumetall) dimensions: OD=47mm, H=24mm, thickness=0.3мм
Available turns ratio: 0.5+0.5:2+2; 0.5+0.5:4; 1:2+2; 1:4
Typical primary inductance: 17H (for 1:4, 1:2+2 types)
Typical primary DC resistance*: 10 Ohms
*Can be down to 5 Ohms on request
Typical secondary DC resistance: 240 Ohms
Frequency Responce of transformer with ES9038q2m at 1.4VRMS (~8kOhm in secondary loaded on 100pF cable): 20Hz=-0.3dB, 20kHz=-0.2dB (rel.1kHz):
View attachment 705302
Same, but with 470pF in parallel with secondary:
View attachment 705303
The possible output level depends on the output current of the DAC (and I/V resistance). In practice it sounds without problems on LF and HF with +/-2mA DAC types such as PCM63\TDA1541 at 2Vp level (1.4VRMS). Less powerfull DACs like PCM58 with +/-1mA have good enough HF even with 1.3Vp witout next buffers.
Here is an example of connection:
View attachment 705329
The price for matched pair (using PELSHO wire) is 150 USD including worldwide shipping. Lead time depends on order. Thanks.
BR, Ivan.
Can a trafo with a single secondary drive a differential amp input when the primary has a differential input with no ground reference, like with Sabre or AKM?
I can understand the need for 2+2/0.5+0.5 to get a differential output when the primary is referenced to ground (like PCM1792 or single ended DAC), but it seems like you shouldn't need it for the 9038 .
BTW I am using your trafo with TDA1387 NOS DAC at the moment.
The trafo is a much better match for this NOS DAC than the 9038Pro DAC, it sounds better than any delta sigma DAC Ive heard too.
I can understand the need for 2+2/0.5+0.5 to get a differential output when the primary is referenced to ground (like PCM1792 or single ended DAC), but it seems like you shouldn't need it for the 9038 .
BTW I am using your trafo with TDA1387 NOS DAC at the moment.
The trafo is a much better match for this NOS DAC than the 9038Pro DAC, it sounds better than any delta sigma DAC Ive heard too.
There is no relation between both the primary source + coil (no matter if it balanced or single ended signal applied) and the secondary coil\coils, because they are galvanically isolated. I have version 1:2+2 too. If your amplifier can handle sound without ground reference then yes, you can use only one secondary coil.
Interesting
Is there any additional info regarding signal level and frequency response \ quality on LF when use with 1387? One 1387 chip or parallel circuit?thanks, although I still need to build the 2nd HP amp to use 2 of them in a balanced configuration I can still test 1 amp in 'mono' balanced and see how it works first.There is no relation between both the primary source + coil (no matter if it balanced or single ended signal applied) and the secondary coil\coils, because they are galvanically isolated. I have version 1:2+2 too. If your amplifier can handle sound without ground reference then yes, you can use only one secondary coil.
Interesting
I have only messed around briefly with TDA so far, there was around 8 of them in parallel and output level was much higher than necessary.
Considering the cost you can stack as many of these chips in parallel as you like, but im not noticing much real benefit to it ... others even reported negative effects to SQ for some DACs.
I guess its down to how well the chips are matched.
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Hi guys, I got my trafos from Ivan. They are great! I love them! See my comparsion with other output stages on this post:
https://www.diyaudio.com/forums/pc-based/335881-iancanadas-rpi-gb-goodies-impressions-tweaks-mods-hints-57.html#post5840833
Now, I am ordering voltege out model from Ivan to compare them to my Teramotos Finemet on ak4497 dac.
https://www.diyaudio.com/forums/pc-based/335881-iancanadas-rpi-gb-goodies-impressions-tweaks-mods-hints-57.html#post5840833
Now, I am ordering voltege out model from Ivan to compare them to my Teramotos Finemet on ak4497 dac.
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