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Old 5th May 2012, 05:56 PM   #1
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Default RCA RS177H just dosen't sound right! Caps?

I just finished replacing all the power and coupling caps and all the resistors on this and while it plays good and has bass the treble is just too high and sounds kinda "SCRATCHY" not smooth? I used metal foil coupling caps at .27uf just as the schematics called for? Should I have increased them to say .35uf?
Thanks as always for your time and thoughts folks
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Old 5th May 2012, 07:09 PM   #2
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If you have replaced all the original paper capacitors with modern plastic dielectric types, the frequence response will be increased on the high end over what it was, And if you replaced the original carbon composition resistors with metal films, that exacerbates the problem. Somewhat less so for carbon films. It is not the numerical value, but the material "upgrade" that does it.
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Old 5th May 2012, 07:15 PM   #3
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Maybe now you are really hearing how it should sound. Give your brain some time to adjust, maybe it is still "compensating" for the high-end drop that it experienced before.
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Old 5th May 2012, 08:41 PM   #4
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Well I'll try giving it a while It's just the high end sounds a little distorted.
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Old 5th May 2012, 08:49 PM   #5
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I don't have a copy of the schematic. If there is a capacitor in the feedback network, make sure that it's the correct value.
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Old 5th May 2012, 09:04 PM   #6
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There is but I did leave those two and a power cap resistor orginal.
I cant seem to get the schematic to up load as it sayus the file is too large?
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Old 5th May 2012, 09:10 PM   #7
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Please email the schematic to me. You should be able to find my email address by looking at my profile.
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Old 5th May 2012, 09:11 PM   #8
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The site doesn't show my email address. Email me through this site and I'll respond. That will give you my email address.
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Old 5th May 2012, 11:26 PM   #9
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Quote:
Originally Posted by Frank Berry View Post
The site doesn't show my email address. Email me through this site and I'll respond. That will give you my email address.
E-mail sent
Thanks
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Old 6th May 2012, 01:44 AM   #10
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Well I took out the 5AS4A rectifier and rolled in a 5U4G and it sounds a LOT Smoother now
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