Even though I am not there, as soon as I read “smoke” I instantly smelled it. That’s a smell you never forget.
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I think “pungent” is what comes to mind.
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A poignant pungant 
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@yuriy , is my way right?
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@lufubu There is no way back! 
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I had some members ask about extremely low output impedance loads on the new transformers. (600 ohm)
The result is no or little change in FR or Distortion. This means you can drive just about any load with the DS that has these transformers with no change in sound.
Without level compensation:
With level compensation:
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What are you guys doing here, adding output buffers? T
I am planning to change opamp with @yuriy method. from 8132 to 8139
remember, the final Mk I Tuning is, to put in the Mk II boards and do the transformer mod there 
So 8139 with a bi-polar supply I assume? That does work well sonically as it allows you to eliminate DC blocking on the output. But there are tricks required to do that as the layout is intended for single polar. Is there a a post where Yuriy covers all that? T
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They are just adding and beefing up the supply feeding the 8139 opamps. No bipolar.
Ahh I see. So basically supporting higher power to the 8139, but still unipolar. Cool.
You can also raise the supply voltage while you’re at it. This extra supply headroom allows a higher Rfb (higher OA gain) and you can then get a bit more amplitude out of it. I raised the voltage to ~ 10.xV on DAC2 and then maximized the gain and output level on it.
You don’t want it to approach “clipping”, of course. I found that you can see when the OA is getting unhappy via monitoring the supply current to it; it tends to scale properly with increasing gain, what I would call linear mode I guess, but it starts to rise abnormally once the OA has had enough. Back off a click from that point and you have optimal output level.
My thinking is, more output level could also help the S/N ratio. I think maximized SN is a good thing here for what we’re doing.
This did allow the highest THD+N I was able to see on my simple meter, about -80dB on DAC2. I still use the stock local regulator in it but I think it is very high performance. It did require a few components changed to handle the higher Vout, along with a higher Vin feed point (to be able to reach 10.xVout). And I did beef up the supply side capacitance in particular. But I did only use (2) 8139 per channel, to answer the power issue. Seems to work very well. DW continues to use it in his very high performance system. Beat the sound if you can, is what my ears suggest at least
In comparison, I see about -65 baseline on DAC3, which has only Vocm mod and JK trafos in it so far.
The word of the day for me is “AVC”… It arrived. I’m loving it so far(!)
T
DW system currently:
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Sorry but I don’t have enough technical knowledge. Only by imitation can I have my technician make the change to this setting.
I’ve been working on practice boards because my tech, who is my age (46), says his sight has worsened considerably over the last year. It’s fun to learn new things and work hard. Soon!
Haha… good work! Your tech is a whippersnapper, sonny T
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My job is to be a judge. I’m not bad at electronics for what I do. But that’s all. I regret that I did not develop myself in electronics in time.
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…and you guys do fantastic, actually IMO. Highly intelligent and good listeners! That’s why I love this forum in particular… TK
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In fact, just a suggestion to make things a bit easier. But you could also use the stock local reg and just feed it from the new LPS. Perfect solution, IMO. Easier. Can also increase Vout while you’re in there and go up a click or two on OA Rfb and output level as well. I think the 8139 also can swing closer to the rails vs the 8132. TK
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amazing four for me, @tedsmith, @Turbotk,
@yuriy
@jkrichards
And
@vkennedy61 (back vocals)
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