Hi Terry,
Theoretically I can make some remote comparison measurements like I did for this Sowter' transformer (compareble specs to mine): 9762 DAC Interface Transformer :
But there can be some unaccounted things during measurements at both sides
...
If somewhere in the internet there will be a straight measurement of the branded transformer connected to the real DAC chip, then I agree it will be useful to make similar measurement. AFAIK Jensen/Cimemag/Lundahl/Sowter have not use so called "nanocrystallyne" core material. From practice I know that in terms of Sound Quality it is more important than THD measurements... So that is why I believe the real listening tests gives to me and to my clients much more benefits than the abstracted measurements.
But I am ready to discuss measurements if you will point to any you want to compare with.
I have discovered this direction previously and found some solutions, but again it is the task more for the specific case of specific DAC usage, than to transformer's specs.
Take a look to the measurements I have made for different DACs and different digital LPFs:
1) PCM63 in NOS (no digital LPF) mode loaded to my transformer (without extra circuits after or before):
2) ES9038Q2M (chineese Smpcb 1.07) with regular i/v stage on 5532 OpAmp (factory default) in different digital LPFs (it is impossible to use NOS mode as you know):
fast roll-off linear phase
slow roll-off linear
fast roll-off minimum phase
slow roll-off minimum phase
fast roll-off apodizing
fast roll-off hybrid
brickwall filter
Just for reference: as you see the ringing issue is not the transformer's issue. But if you really need to fight somehow with DeltaSigma artefacts as LPF' ringing, then I can recommend to use RC snubber in parallel to the secondary coil.
Here are some findings:
RAWvs-Snabber — imgbb.com
As you see, it is possible to fight with ringing, but the speed of the signal will fall a bit.
Later I will try to find the most-flat-top version for Ian's dual 9038.
Thank you.
Sure I have distortion measurements, some of them you can find in this thread earlier.
Yes, there are a lot of measurements in the net, but I do not see any benefits to make such general measurements without the relation to the DAC chips to which I do making my transformers for.
Theoretically I can make some remote comparison measurements like I did for this Sowter' transformer (compareble specs to mine): 9762 DAC Interface Transformer :
But there can be some unaccounted things during measurements at both sides
...If somewhere in the internet there will be a straight measurement of the branded transformer connected to the real DAC chip, then I agree it will be useful to make similar measurement. AFAIK Jensen/Cimemag/Lundahl/Sowter have not use so called "nanocrystallyne" core material. From practice I know that in terms of Sound Quality it is more important than THD measurements... So that is why I believe the real listening tests gives to me and to my clients much more benefits than the abstracted measurements.
But I am ready to discuss measurements if you will point to any you want to compare with.
Can you point to this findings\discussion please?
I have discovered this direction previously and found some solutions, but again it is the task more for the specific case of specific DAC usage, than to transformer's specs.
Take a look to the measurements I have made for different DACs and different digital LPFs:
1) PCM63 in NOS (no digital LPF) mode loaded to my transformer (without extra circuits after or before):
2) ES9038Q2M (chineese Smpcb 1.07) with regular i/v stage on 5532 OpAmp (factory default) in different digital LPFs (it is impossible to use NOS mode as you know):
fast roll-off linear phase
slow roll-off linear
fast roll-off minimum phase
slow roll-off minimum phase
fast roll-off apodizing
fast roll-off hybrid
brickwall filter
Just for reference: as you see the ringing issue is not the transformer's issue. But if you really need to fight somehow with DeltaSigma artefacts as LPF' ringing, then I can recommend to use RC snubber in parallel to the secondary coil.
Here are some findings:
RAWvs-Snabber — imgbb.com
As you see, it is possible to fight with ringing, but the speed of the signal will fall a bit.
Later I will try to find the most-flat-top version for Ian's dual 9038.
Technically it is not the problem to make such transformer, but it is not economically profitable for me at the moment (have no time and enough financial motivation for R&D).
I believe it the only way to use all the benefits of this core material. If you will split this material then the Efficiency will drop sharply (the situation differes even from amorphus material not to mention permalloy or iron).
As mentioned above here I just have done the measurements of Ian's Dual ES9038Q2Mpi DAC with my transformers (3.9k Ohm load) for different source sample rates and square signals (filter is linear slow roll-off).
SR768kHz - 1kHz
SR768kHz - 20.2kHz
SR384kHz - 1kHz
SR384kHz - 24kHz
SR192kHz - 1kHz
SR192kHz -24kHz
SR96kHz - 1kHz
SR96kHz - 24kHz
And the final, most popular 48kHz (44.1kHz - will be similar):
SR48kHz - 1kHz
SR48kHz - 12kHz
So there is a question: around what measurement do we want "to dance" trying to fight with ringing?..
SR768kHz - 1kHz
SR768kHz - 20.2kHz
SR384kHz - 1kHz
SR384kHz - 24kHz
SR192kHz - 1kHz
SR192kHz -24kHz
SR96kHz - 1kHz
SR96kHz - 24kHz
And the final, most popular 48kHz (44.1kHz - will be similar):
SR48kHz - 1kHz
SR48kHz - 12kHz
So there is a question: around what measurement do we want "to dance" trying to fight with ringing?..
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Deleted member 537459
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Deleted member 537459
Thank you guys for the feedback!
It is the first version of PCB, it was just for my experiments with LPF and i/v at the primary side of transformer (you can find similar components in Ian's LL I/V PCB (DocumentDownload/LL1544aTransformerIvSch.pdf at master * iancanada/DocumentDownload * GitHub). It is not needed normally and probably will be deleted from PCB if the next versions of PCB will occur.
It is the first version of PCB, it was just for my experiments with LPF and i/v at the primary side of transformer (you can find similar components in Ian's LL I/V PCB (DocumentDownload/LL1544aTransformerIvSch.pdf at master * iancanada/DocumentDownload * GitHub). It is not needed normally and probably will be deleted from PCB if the next versions of PCB will occur.
I might also interested in the transformer HAT solution that attaches to IANs dual-mono HAT.
The question I have relates to the amp integration.
I'm currently running an Abletec amp directly connected to my current ES9038Q2M DAC from Audiophonics.
I'm also running 100% software volume control on that DAC .
Can the output level of the transformer be adjusted or customized to better integrate with the amp gain/speaker sensitivity for minimum losses in conjunction with 9038Q2M software volume control??
Usually 2V DAC out is much too high as output voltage for direct DAC->amp coupling. If you'd go balanced out things even get worse.
Thx.
The question I have relates to the amp integration.
I'm currently running an Abletec amp directly connected to my current ES9038Q2M DAC from Audiophonics.
I'm also running 100% software volume control on that DAC .
Can the output level of the transformer be adjusted or customized to better integrate with the amp gain/speaker sensitivity for minimum losses in conjunction with 9038Q2M software volume control??
Usually 2V DAC out is much too high as output voltage for direct DAC->amp coupling. If you'd go balanced out things even get worse.
Thx.
Hi soundcheck,
The answer was here in #146
The given values are the impedances for targeted level: resistors R1a, R1b, R2a, R2b in parallel with the input impedance of the next connected stage (your Abletec Amp for example). Just use the values you needed to be at the desired maximum volume level. Tell me the input impedance and sensitivity of your Amp and I can tell you values of the loaded resistors.
The answer was here in #146
The given values are the impedances for targeted level: resistors R1a, R1b, R2a, R2b in parallel with the input impedance of the next connected stage (your Abletec Amp for example). Just use the values you needed to be at the desired maximum volume level. Tell me the input impedance and sensitivity of your Amp and I can tell you values of the loaded resistors.
Hi Bisesik, I’m interested to buy a kit (trafo + board + components) to put upper the IAN 9038q2m hat dac.
Do you sell it? Which is the cost and how to buy?
I am also interested on the difference I can obtain respect the usage of IAN I/V board with the LL1544A trafo. Which improvements I can obtain?
Now I’m using the opamp board with opa1612 with unbalanced output and it sounds good but I understood that the trafo approach is much better in terms of sound quality
Do you sell it? Which is the cost and how to buy?
I am also interested on the difference I can obtain respect the usage of IAN I/V board with the LL1544A trafo. Which improvements I can obtain?
Now I’m using the opamp board with opa1612 with unbalanced output and it sounds good but I understood that the trafo approach is much better in terms of sound quality