new amp build

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Moosehead2
Junior tube assistant
Posts: 62
(3/31/04 9:09 am)
 new amp build
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 just finished building a 5F2A princeton. Got the parralel 6V6 output and 10 watt hammond OT. The cabinet is a piggy back i built as per Kevin O'Connors de-tuned logic. Check it out
www.rogersamps.com/Blank%...ge%203.htm
 
Crispycircuit
Junior tube assistant
Posts: 16
(3/31/04 10:14 am)
 Nice!
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 To Cool!! I commend you and anyone who finishes a project like this. Your hired!.....You say paraelel 6v6s? That would imply single ended. ????
 
Moosehead2
Junior tube assistant
Posts: 63
(3/31/04 10:30 am)
 re
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 You better believe it! This way you get the simple circuit AND the extra volume instead of just mearly being a practice amp. That was kinda my goal i guess, to maximize the tone and volume of the champ style circuit. I'm sure there is tons more stuff i could try out!
 
LooseChange
Senior tube assistant
Posts: 230
(3/31/04 10:39 am)
 Re: You gonna take the hood off so we can see inside???`
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Really nice lookin' amp!
 
bluesbear
Hey get your own solder
Posts: 356
(3/31/04 11:21 am)
 Re: new amp build
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 Beautiful job! I plan on building a Champ type amp with 2 power tubes in parallel, probably next week, that will run on 6L6's or EL34's. I'm hoping for about 25 watts.
Dave
 
teletroy
Junior tube assistant
Posts: 8
(3/31/04 1:40 pm)
 sweet
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 Just wondering if you have any shots of insides? Or maybe even a layout? I love looking at the guts of these things. :)
 
Moosehead2
Junior tube assistant
Posts: 65
(3/31/04 1:52 pm)
 re
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 Ya i'm a little short on pictures at the moment. I'm planning on taking more though. I'll let you know.

Edited by: Moosehead2 at: 3/31/04 1:53 pm
 
Ritchie200
Senior tube assistant
Posts: 179
(3/31/04 1:58 pm)
  Re: re
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 WOW!, great build. How long did it take you to match everything on that cover job? Fine job!
Jim
 
j allen shaw
Junior tube assistant
Posts: 31
(3/31/04 7:29 pm)
 Re: tubes run parallel??
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 The (2) tubes run parallel is very interesting.
Can someone explain how that is done? Is it as simple as installing another socket & connecting pin 1/v1 to pin 1/v2, pin 2/v1 to pin 2/v2 & so on, or is there more to it than that?
What about bias considerations? Would the cathode bias resistor need to be adjusted up or down?
Would it be possible to run (3) tubes, or even (4) tubes in parallel if the PT & OT would handle it?


Edited by: j allen shaw at: 3/31/04 7:45 pm
 
bluesbear
Hey get your own solder
Posts: 358
(3/31/04 9:19 pm)
 Re: tubes run parallel??
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 "Is it as simple as installing another socket & connecting pin 1/v1 to pin 1/v2, pin 2/v1 to pin 2/v2 & so on, or is there more to it than that?"
The plate and cathode are tied that way. I haven't quite figured out what to do with the screen and grid (someone please straighten us out on this). I'd run the heaters the same as for any amp.
"What about bias considerations? Would the cathode bias resistor need to be adjusted up or down?"
I don't know. I'd just measure the current. For cathode bias amps, I have a 25 watt, 750 ohm rheostat I use to get the current correct, then I measure it and replace it with a resistor. Perfect every time.
"Would it be possible to run (3) tubes, or even (4) tubes in parallel if the PT & OT would handle it?"
Yes. At Antique Electronics, I've seen single-ended OT's up to 60 watts.
Dave
 
Moosehead2
Junior tube assistant
Posts: 66
(3/31/04 11:08 pm)
 re
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 Plates are tied together as well as the screens. The Cathode can share a resistor or you can seperate them. The grids each need their own resistor but can share the grid leak resistor. When adding a second tube in the champ circuit each tube shares the current so the 450 ohm cathode resistor will be 225 ohm or you can give each tube their own 450 ohm resistor.
 
Lucid Alice
Senior tube assistant
Posts: 184
(4/1/04 10:44 pm)
 Re: re
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 Nice Job!

I'd love to see a schematic of that. I'm no engineer, but if the tubes are getting the current they want you should be getting 3 to 6 db more than a single tube! That's a lot more sound!

 
trescat
Junior tube assistant
Posts: 17
(4/1/04 11:39 pm)
 Nice amp
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 I also have made a Princeton 5f2 but with just the single 6V6 , I was wondering where do you get the "Rogers" name plate made up thats pinned to the front of your amp??

Cheers
Trevor
 
Moosehead2
Junior tube assistant
Posts: 67
(4/1/04 11:52 pm)
 re
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 Check out www.angela.com they have a schematic for this circuit with some other cool options, look under the how to section.
The name plate is black epoxy ink silkscreened to chromed metal which i screened myself. The chromed metal is actually an old toaster i cut up..same with the face plate!
 
 
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