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Hoffman Amps Forum image Author Topic: Champ 5f1 build  (Read 2089 times)

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Offline dbsamithey

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Champ 5f1 build
« on: May 23, 2022, 11:48:58 pm »
Just put some finishing touches on a champ 5f1 build.  Mods include a VVR (visible on the left hand side of the photo of the chassis) and a tone stack (visible on the right).  With the VVR at the lowest voltage the amp puts out some great sounding distortion at low volume.  I doubt I'll use the tone stack much but there is a DPDT switch that removes it completely from the circuit, so the only downside is the extra wiring.  I got the cabinet from http://rawcabs.com/Welcome_page.html and put a few applications of tung oil into it. 

Offline Latole

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Re: Champ 5f1 build
« Reply #1 on: May 24, 2022, 03:03:22 am »
You are very clever to have managed to fit all these parts in such a small chassis.
Interesting this cabinet maker


Offline Williamblake

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Re: Champ 5f1 build
« Reply #2 on: May 24, 2022, 07:09:33 am »
Very nice, but there is two switches at the tone stack?

Offline dbsamithey

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Re: Champ 5f1 build
« Reply #3 on: May 25, 2022, 12:45:26 am »
Thanks a lot.  Oh yeah the switch on the bottom right is a NFB resistor selector.  I hope that all of the extra components aren't increasing the background buzz too much.  I figured I would experiment with lots of mods just for the fun of it.  The VVR came last and is far and away the most worth the extra clutter.  Maybe the mosfet is bad juju for a tube amp though.  I really like the cabinet too - I ordered it with a request to the maker for an extra inch of depth beyond spec and soon received it in the mail smelling of fresh cut pine.

Offline PRR

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Re: Champ 5f1 build
« Reply #4 on: May 25, 2022, 06:16:35 pm »
> smelling of fresh cut pine.

I once had a date with a surgeon but was cutting wood just before I went. He winced as he came into the exam room. To him, that smell means another damfool had sawn-off finger or hand and wants the goulash put back together.

I think of him every time I have a near-miss with a sharp tool. (This week's injury is a blunt object and will heal itself. I was using a chainsaw, bloodlessly, but musta banged myself real good.)

Offline shooter

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Re: Champ 5f1 build
« Reply #5 on: May 25, 2022, 06:37:22 pm »
Quote
I was using a chainsaw, bloodlessly,


last week chain grabbed the loose pants, small trickle, small scab, Large Thanks
Went Class C for efficiency

 


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