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6V6 line preamp
6V6 line preamp
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Old 22nd March 2013, 03:49 PM   #1561
iko is offline iko  Canada
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Nope, my 26 has a ixcp10m90s gyrator load and cap output. No cash for a good output transformer.
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Old 22nd March 2013, 03:57 PM   #1562
Salas is offline Salas  Greece
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I am sure it measures much better that way.
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Old 22nd March 2013, 04:08 PM   #1563
stajo is offline stajo  Sweden
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Well sqarewaves are squarewaves and music is music. Squarewaves are good for tracking problems, not so good for judging the goods or bads in a music machine. No news for anyone here I guess.

Vgeorge, I wouldnt be surpriced is the 25 mA iron is on the edge of saturating, and that might be what we are looking at.

There is lots of line trafos that leaves unnoticable footprints on squarewaves, I think its more of an implementation thing.
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Old 22nd March 2013, 04:12 PM   #1564
Salas is offline Salas  Greece
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Still the wiggle was no accident, it denoted resonance that manifested in excess microphony. Choke load takes double the Ip spec and a snubber it seems so to be judged correctly. It owes to bring less THD and more gain to the plate but in a behaving manner.
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Old 22nd March 2013, 04:20 PM   #1565
stajo is offline stajo  Sweden
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Amen to that. I merely ment that one shouldnt diss iron as a concept based on a single implementation.
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Old 22nd March 2013, 05:19 PM   #1566
vgeorge is offline vgeorge  Greece
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Correct Stajo. I don't dismiss iron, in fact I try to use it most possible. Just this iron in this implementation did not work out. In fact in my power amp I m using now have some nice Hashimotos!
Even if I solved the slight ringing on the scope, I should take extreme measures to avoid microphonies.
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Old 22nd March 2013, 05:22 PM   #1567
vgeorge is offline vgeorge  Greece
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Quote:
Originally Posted by iko View Post
Nope, my 26 has a ixcp10m90s gyrator load and cap output. No cash for a good output transformer.
If your power amp has a highish input impedance that' s fine!
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Old 22nd March 2013, 07:49 PM   #1568
vgeorge is offline vgeorge  Greece
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I found some Mills 6,8K resistors and put them in.
Plays beautifully now! Excellent sound, I m thrilled!
I will get a stronger subchassis for the parts and rearrange things a bit in the future, now that I do not use the chokes.
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Old 22nd March 2013, 07:53 PM   #1569
iko is offline iko  Canada
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Seriously, the two resistors made a difference in sound?
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Old 22nd March 2013, 08:11 PM   #1570
vgeorge is offline vgeorge  Greece
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They were better suited to this circuit compared with the chokes I used. Maybe other chokes would perform better. Resistors were less prone to pick up vibrations mainly, that resulted in clearer sound. Still need work t do on the chassis as I said.
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