Please help me tweak my amp...

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Ag_Nathus
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Please help me tweak my amp...

Post by Ag_Nathus » Sun Apr 03, 2011 9:49 pm

Standard plexi lead kit with regular sozos. It sounds good enought that I have been playing it, but I would like to take some time to get it "bulletproof".

As it is, my issues are:

1. General noise on the two imputs (check the sound clip)- not too bad but I would like to get it quieter if anyone has any tips.

2. Jumpering the two channels together creates a LOT of noise (again, check the sound clip), anyway to eliminate this would be very helpful!

3. Presence still squeals above 1/2 or so- any further ideas on how to minimize this?

I have switched guitars and cables so it is an amp issue. I can post any pictures that would be helpful.

Sond file details:

http://www.zshare.net/audio/88596499b0e7f7a4/

Presence: 2
Treble: 8
Mid: 8
Bass: 8

Volume 1: 9
Volume 2: 9

First 2 parts of the clip are on the bright input (I), 3rd part is dark input (II) and the 4th (noisy) part is the jumpered channels.

Please excuse my somewhat doofy playing, I was trying to focus on the noise issues more than the "jamtasticness" :)

Thank you for any possible help!

AG

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toner
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Location: Iowa

Re: Please help me tweak my amp...

Post by toner » Sun Apr 03, 2011 10:09 pm

I didn't listen to your clip (18.33MB :shock: ) but the noise is likely a preamp tube. Try replacing them, starting with V1.

RE: presence squeal; Check the wire that runs from the presence pot to the board. Keep it as short as possible and away from other wires (especially the OT and tone controls).

Ag_Nathus
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Re: Please help me tweak my amp...

Post by Ag_Nathus » Mon Apr 04, 2011 12:15 am

toner wrote:I didn't listen to your clip (18.33MB :shock: ) but the noise is likely a preamp tube. Try replacing them, starting with V1.

RE: presence squeal; Check the wire that runs from the presence pot to the board. Keep it as short as possible and away from other wires (especially the OT and tone controls).
Heh, I think you can stream it :) Would a bad preamp tube cause more noise with the channels jumpered?

Thanks!

AG

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toner
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Location: Iowa

Re: Please help me tweak my amp...

Post by toner » Mon Apr 04, 2011 12:56 am

Ag_Nathus wrote:Heh, I think you can stream it :) Would a bad preamp tube cause more noise with the channels jumpered
Firefox didn't find a plugin but I just listened to it in IE...

Okay, I was thinking "hiss" noise but not after hearing your clip. It could be several things but tubes is the first to check. You've got some nasty distortion when jumpered. It's probably V1 but could also be the added gain pushing V2 or V3 into that clipped grunge. Does the distortion sound the same with the bass on zero? If it doesn't clip as harshly with the bass down, it's likely V3.

Try a different preamp tube in each position one at a time. Check the bias too (might be the power tubes).

Still no luck? Post pics or voltage readings. Hope this helps.

Ag_Nathus
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Posts: 20
Joined: Sat Oct 18, 2008 4:27 pm

Re: Please help me tweak my amp...

Post by Ag_Nathus » Mon Apr 04, 2011 1:07 am

toner wrote:
Ag_Nathus wrote:Heh, I think you can stream it :) Would a bad preamp tube cause more noise with the channels jumpered
Firefox didn't find a plugin but I just listened to it in IE...

Okay, I was thinking "hiss" noise but not after hearing your clip. It could be several things but tubes is the first to check. You've got some nasty distortion when jumpered. It's probably V1 but could also be the added gain pushing V2 or V3 into that clipped grunge. Does the distortion sound the same with the bass on zero? If it doesn't clip as harshly with the bass down, it's likely V3.

Try a different preamp tube in each position one at a time. Check the bias too (might be the power tubes).

Still no luck? Post pics or voltage readings. Hope this helps.

Thanks, I will play around with these ideas and post back. If anyone else has any other suggestions to try while I am at it, please let me know.

Thanks for all the help!

AG

Ydna
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Posts: 307
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Just the numbers in order: 7
Location: Livermore, CA

Re: Please help me tweak my amp...

Post by Ydna » Tue Apr 05, 2011 12:12 pm

I'm just curious, what did you use to record this?
~Current Amps~
1. 1963 Sano Supersonic
2. 1990s Fender Dual Showman
3.JTM45/100 Build

~Future Amps~
1. 69 Superlead
2. Lots of Metropoulos amps

Ag_Nathus
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Posts: 20
Joined: Sat Oct 18, 2008 4:27 pm

Re: Please help me tweak my amp...

Post by Ag_Nathus » Wed Apr 06, 2011 1:37 am

a 57 into a korg D3200.

AG

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