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Old 29th December 2008, 01:58 PM   #1
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Default I got bored

Well, its not a gainclone. Its TDA7294, hot rodded just a bit.
Not shown is an additional 100nF underneath because I ran out of room on these boards. Its a dual mono arrangement. I don't have the buffers or the power supplies done yet.
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Old 29th December 2008, 06:29 PM   #2
Nuuk is offline Nuuk  United Kingdom
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Does it help using different brands of decoupling caps for pos and neg rails?
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Old 29th December 2008, 06:51 PM   #3
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Quote:
Originally posted by Nuuk
Does it help using different brands of decoupling caps for pos and neg rails?
Would it hurt?
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Old 29th December 2008, 06:56 PM   #4
Nuuk is offline Nuuk  United Kingdom
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Quote:
Originally posted by pacificblue

Would it hurt?
Not at all but I was bored too!
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Old 29th December 2008, 10:57 PM   #5
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Quote:
Originally posted by Nuuk
Does it help using different brands of decoupling caps for pos and neg rails?
Oh, thanks for pointing this out. Those are Boostrap 47uF, NFB 22uF.
However, I wouldn't want it to look like there was something wrong.
And, I'm still bored. This amp needs more decorating.

P.S.
This decorating stuff is an unusual thing for me to do. My usual amp turns out brown&black with nice components of mundane appearance.
But, this amp gives that much larger than life presentation, so I thought it should look like it. Other than appearance, there's no significant difference from the working model.
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Old 30th December 2008, 12:08 PM   #6
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Default Much more decorating!

That was still a bit boring, so I decided on some extraneous precision at the resistors, something decidedly unmistakable, and lots more color.

I got the model unit up and running again today. Its been in storage. Its not as pretty to look at; but, wow, it does do well. It took a minute to get used to it because its sound isn't typical for solid state. We're still jammin out. Exuberance is coming along nicely.
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Old 31st December 2008, 06:00 AM   #7
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Plan "B" is an ordinary paralleled LM3886 (reduces odd harmonic noises if used parallel) with limited gain (further reduce its signature) plus a preamp, and maybe, just maybe keep LM3886's gorgeous baritone feature and absolutely no shout. Can we Accentuate the Positive?
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Old 31st December 2008, 09:40 AM   #8
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hi danielwritesbac,

Does the gold paint contain real gold?

regards
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Old 31st December 2008, 02:18 PM   #9
DcibeL is offline DcibeL  Canada
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Does the gold paint make the amp sound richer?
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Old 31st December 2008, 05:17 PM   #10
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Quote:
Originally posted by Greg Erskine
hi danielwritesbac,

Does the gold paint contain real gold?

regards
Hi Greg!

The paints are all lacquer, some of which contains brass. The big polyester (positioned "barrier cap" also called Rail2Rail) has the metalized lacquer. An ordinary chinese "mylar" dip cap can do just as well there (see the footnotes of the CarlosFM 2005 supply). On the electrolytics its yellow dye with a lot of clear lacquer. There was actually a reason. The three caps that got lacquered are well working ordinary components. I didn't want these amplifiers to sound different than the working model, so I used the same components. . . now all dressed up for the discotech. lol!

I'm having some trouble with the "scale" of this amplifier. It plays nearly compression-free, having wasted about a third of its output power. Of course! Now that I type that, it makes sense. That's similar to the consequences of an un-compressor or non-compressed live music playback. A very weird thing is that, the power supply is warm, but the amplifier's heatsink isn't.

Is it that non-blaring doesn't play loud enough or is it that I'd like it louder?
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