Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: LooseChange on November 20, 2010, 09:53:23 am
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Just finished up - still burning a tweaking another Desktop Studio Model.
Stupidly named the "March" because it's a Champ with a Marshall JCM800 front end.
Got another name... Let me know.
I wanted to build another Desktop Studio Champ because I actually don't own one and love the way they sound. But I've been wanting to do a Desktop Studio JCM800 so I added it.
High input is like the High input on the Marshall.
Low input is the Champ.
No low input Marshall.
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Another bewdy! :glasses9:
Does the "Half" switch put a big dropping resistor in the power rail?
Cheers,
Chip
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Very nice!
Is it fixed bias or is the bias pot part of the cathode resistor?
How about:
JChampM800
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Very nice work LC. You certainly got the curb appeal down on the packaging! Regards
dennis
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Thanks! You guys like the look I've been going for?? I still want to come up with cabinet for these for road use. I was thinking of the standard sleeve with four holes drilled out in the bottom to let the feet slip into and keep the amp from sliding out. What do you think??
Hey Chip... The half power is the basic Pentode/Triode switch. It is just okay on the Champ but with the Marshall high gain and treble like tone the half power switch is great.
I was thinking of using a big dropping resistor in the power rail but didn't didn't do it. I would like to try it still.
What value and wattage would you suggest to drop the voltage to about 150v??
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Nice build! I think something like an 18watt style cabinet (only smaller) with maybe with a hardwood front panel (like the trainwrecks) and your idea of the drillouts on the cab floor for the chassis feet would be the cats meow. Forstner bit would do it.
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good looking stuff LC :-)
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LC- I guess you were thinking of a metal cab. In either case (wood or metal cab), how would one attach the cab to the chassis?
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Sweeet looking amp LC..
Q: How do you like those blue molded Sozo Caps?
Best Regards,
Rzenc
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I was thinking of a wood cabinet actually.
Those blue Sozo's were a pull from another build and they do sound great (broken in too).
The amp is cathode biased with a 100ohm - 5 watt pot used to adjust the bias.
So, no other name suggestions except for VMS??
Stick with "March"?
Today I spent some time tweaking and comparing the JCM tone to a really nice sounding JCM800 clone. Got them to sound very close to each other.
Thanks for all the nice comments!!
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or "MarChamp"
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if the letters don't necessarily have to follow part-word form, then how about...
CharM.
--ISO
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The March is sticking. I have had many try out this amp and all say it sounds amazing with incredible versatility. Just thought you all should know. :smiley: