Help on a old Silverface

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fusionbear
Posts: 478
Joined: Thu Nov 01, 2007 4:42 am
Location: Southern California

Help on a old Silverface

Post by fusionbear »

Hello everybody. I recently worked on an old 73' silverface vibrosonic that gave me fits, but I eventually Blackfaced the inverter circuit and replaced most of the electrolytics. The customer just made me aware that when he plays live with it, the amp is loud and clean, but after a couple of hours of playing, the amp looses half of its volume. Any Ideas? He hasn't returned the amp yet, but will in a couple of days. Any help would be appreciated...
Learning to learn...
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Structo
Posts: 15446
Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: Help on a old Silverface

Post by Structo »

So it's heat related.
Check
Tube(s)
Solder joints
Carbon Comp resistors
Tom

Don't let that smoke out!
Firestorm
Posts: 3033
Joined: Fri Jan 25, 2008 7:34 pm
Location: Connecticut

Re: Help on a old Silverface

Post by Firestorm »

Power transformer, too. See if the voltage drops when it's hot.
Andy Le Blanc
Posts: 2582
Joined: Sat Dec 22, 2007 1:16 am
Location: central Maine

Re: Help on a old Silverface

Post by Andy Le Blanc »

How much rust is on the trannies?
lazymaryamps
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M Fowler
Posts: 14036
Joined: Wed Jan 16, 2008 2:19 am
Location: Walcott ND

Re: Help on a old Silverface

Post by M Fowler »

Heck per the experts rust is suppose to make the trannies run cooler and better. :)

Mark
C Moore
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Joined: Mon Oct 22, 2007 9:28 am
Location: USA, California, 94585

Re: Help on a old Silverface

Post by C Moore »

You replaced MOST of the electrolitics....???
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