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Old 16th January 2012, 12:04 PM   #411
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Your variable resistor is nevertheless a good idea...
You want to watch the temperature derating on whatever you use.
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Old 16th January 2012, 01:01 PM   #412
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I am still fighting to get closer to the sweet spot...
At approx. .1% THD, predominant second, I'd say you're doing quite well.

Now, twist the knob and watch the spectrum change. Fun, fun, fun.

BTW, are those 50V caps?
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Old 16th January 2012, 01:05 PM   #413
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Elna 10000uF/63V......

Yes i saw already the change... But i did not change during hearing.....
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Old 16th January 2012, 01:10 PM   #414
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Thanks, just checking.

My guess is the junk at the bottom is souncard / PC related, at least in part. Is that at 1W?

You could do a loopback and check the residual spectrum.

Last edited by Michael Rothacher; 16th January 2012 at 01:35 PM.
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Old 16th January 2012, 02:29 PM   #415
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Way too hot inside that case, and that's probably not making your transformer happy either. Move those resistors outside or get bulbs. Have a look at my post on resistors, the ones I used are 4 times as big, and I used three for each channel.

Keep going, you're almost there.
i lost my AAA but i ordered 2X 800W thick film resistor with heatsink and 2 3,3ohm 100W .. and a isolation TRansformer .. i' m on the run
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Old 16th January 2012, 09:22 PM   #416
generg is offline generg  Germany
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I am speechles........even with AAA.....what big jump!

That will solve your problems I suppose, do you need more heatsinks?
Would be nice if you could keep your wooden case, looks better than these mostly cheap metallic cases that are mine.

Maybe I will change too, but keeping the heatsink area!

Hope my trans- and re- sistors will come soon...

And I built up in the evening the SK79 and SB624 circuit I posted some days ago, again too late to hear loud, but it seems not contra productive to the SIT amp.....
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Old 16th January 2012, 10:45 PM   #417
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Thanks Michael
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Old 19th January 2012, 02:13 PM   #418
generg is offline generg  Germany
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Hi everybody,

some news,

1. I could change my wire resistors today against thick film resistors.... that is a heavy difference.......I was shocked.....I like it much more!

2. my new arranged Mufollower was better than the wire resistor version, more alive...but more cap dependent, two caps.....and now compared to the thick film solution, less precise and a bit veiled, but more bass with my tone tubby/lowther and more gain.....

the affair stays amusing.......

and Salas, CCSs must wait still a bit, I have to change the PSU from 48V again back to 27 or 18......
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Old 19th January 2012, 02:18 PM   #419
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Gerd,
What brand, how many of what wattage thick film resistors. I have thought about parralleling a few 100W thick film types.
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Old 19th January 2012, 03:07 PM   #420
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still having some noise on the speaker, do you think putting a RC snubber across the bridge rectifier will help? any value
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