Marshall 8200 Bi-Chorus Head - Oh poop!!! Its NAD:

So, today I'm gonna give it a good blowing out with compressed air, clean all the pots and momentary push buttons with DeOxit F5, install a new preamp tube (JJECC83S Gold Pin) glue the ripped "flag" of Tolex back in place with contact cement, clean the reverb tank, go into the jacks with F5 on a Q-Tip and give the cabinet a good general cleaning with Tub 'O Towels.

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Robert Herndon said:
So, today I'm gonna give it a good blowing out with compressed air...
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That's also a good way to visually see for loose components, like resistors, caps, and wiring. Then follow your blow job with chopsticking all the components with the amp unpowered, and again after powering up the amp. Pay special attention to the big white-chalky power resistors. These heat up the most, and if cold solder joints have developed, it would probably start here. I wouldn't replace the preamp tube until everything else checks out.
 
Robert Herndon said:
So, today I'm gonna give it a good blowing out with compressed air, clean all the pots and momentary push buttons with DeOxit F5, install a new preamp tube (JJECC83S Gold Pin) glue the ripped "flag" of Tolex back in place with contact cement, clean the reverb tank, go into the jacks with F5 on a Q-Tip and give the cabinet a good general cleaning with Tub 'O Towels.

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I think replace all the jacks.
 
Clockworkmike said:
Nice score! Hope you enjoy it

Im a fan of finding and using "lesser" gear in the eyes of others, because it keeps you unique and makes you learn how to really use something. Valvestates are fine amps that have been sadly overlooked like many others over the years and can work amazingly in the right hands.

Ill say this: id rather see someone go get something usable and practical that not only sounds great but that you can actually work with. Better to buy something that is affordable that works, rather than go out and buy something overly inflated in its price, it's name and worse: you cant even really use it.

Pricetags dont make you a better musician, just like buying a $50k kitchen appliance set isn't gonna help if you cook if you dont even know how to use a microwave.
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Mike, I would immediately go install 5 layers of tin foil on your head. Not only have you bucked the trend of every marketing commercial on TV, radio, internet, and MTA busses, but you have indeed posted some subversive crap that the government is already tailing you and has your I P address due to how it hit a red flag on the internet trackers. I think we may have to somehow put you in Wav's witness protection program now.
 
Robert, How much does this Valvestate weigh? I am guessing the transformer is not a very heavy unit. I am guessing it might be the equivalent to my Ashdown Mag 300 H Bass head. 10-14 lbs maybe?
 
syscokid said:
That's also a good way to visually see for loose components, like resistors, caps, and wiring. Then follow your blow job with chopsticking all the components with the amp unpowered, and again after powering up the amp. Pay special attention to the big white-chalky power resistors. These heat up the most, and if cold solder joints have developed, it would probably start here. I wouldn't replace the preamp tube until everything else checks out.
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Good idea!
 
chilipeppermaniac said:
Shewie, So many versions I never knew even one of existed before this week. The 2nd ebay one I posted had such bad pics and low details I could not compare to Rob's.
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The Stereo Bi-Chorus are the rarest of all models...they will produce Stereo effects from a single, 2x12 cabinet, and the clean and dirty channels have totally separate chorus sections...through two separate, left and right power amp sections.

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Chorus has two different modes.

Mode Select Switch (A/B)Manually switches from mode A, flange type chorus, to Mode B, traditional chorus.21.

Chorus Rate (Normal)Controls the speed of modulation of the chorus effect on the normal channel.

22. Chorus Depth (Normal) Controls the modulation depth of the built inchorus effect on the normal channel.

23. Chorus Rate (Boost)Controls the speed of modulation of the choruseffect on the boost channel.

24. Chorus Depth (Boost)Controls the modulation depth of the built in
chorus effect on the boost channel.


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These amps use the P803 two button footswitch.

I have a brand new PEDL-90112 two button footswitch from a Marshall Origin.

Both are single, 1/4" TRS style.

Think they are compatible???
 
chilipeppermaniac said:
Mike, I would immediately go install 5 layers of tin foil on your head. Not only have you bucked the trend of every marketing commercial on TV, radio, internet, and MTA busses, but you have indeed posted some subversive crap that the government is already tailing you and has your I P address due to how it hit a red flag on the internet trackers. I think we may have to somehow put you in Wav's witness protection program now.
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Lmao that was pretty good! Im so far off the radar, Im now Stealth
 
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