Build Your Own Clone Message Board

Okay so I finally had time to finish the amp. A few notes:

- Cabinet by Mather Amp Cabinets. Champ style w/ 8" speaker cutout. Lacquered tweed. Custom cutout on back board.
- The rear vent cover is from Fender. Fender doesn't sell them to the general public....so it was a challenge to acquire.
- Variable negative feedback. R10 changed to 9.1K with a push-pull 25K pot. Good tone throughout the sweep of the pot, and can be disengaged.
- C1 is switchable on or off. Using a 22K resistor to eliminate the pop. Seems to work best after the amp has warmed up a bit.
- 4ohm 8" Weber Special Design speaker.
- Rear baffle shielded w/ 2" copper tape.
- NOS GE 5Y3 rectifier.
- Wire preamp tube retainer. Original socket holder ripped apart during a tube change. This seemed like the best choice available w/o resoldering.

....

At 5 watts, this thing screams! Especially with the negative feedback disengaged. Surprisingly loud. I put a treble bleed cap (among other mods) into my '52 Tele RI....and with the guitar volume rolled off and the amp cranked, it's glassy and wonderful.

With C1 switched off, the amp doesn't sizzle nearly as much as when it's switched on. But still really nice tones.

The Tele doesn't "fart out" like other folks have described on their amps. Perhaps due in part to the 4ohm 8" alnico speaker? Or the single coil on the fiddle? I'll have to mess around with the LP a little more on this amp and see what that does.

Also gonna look into power scaling as a way of reducing volume. I've read that pentode/triode switches can be buzzy. I like the idea of a low power switch, like what Fender did on the EC Vibrochamp...but I don't know what their approach is, or how it sounds. I'll probably try out one of those amps in the next few days.

Beautiful

Gorgeous!

You are thinking about power scaling this 5 watter?

Great work.
Do you find the variable feedback useful or do you think an on/off switch would have sufficed?

I'm sure if you googled VVR you'd find good info on power reduction. If you want the cadillac of power reduction check here : http://www.londonpower.com/catalog/inde ... 56fce39aae

Thanks for the compliments, folks! This afternoon I took the finished amp down to True Tone Music in Santa Monica...those folks were extremely helpful in finding some of the cosmetic appointments of the amp. Anyhow, we set it up side by side with an EC Vibrochamp. And the overall consensus was that mine smoked the Clapton! The quality of the BYOC parts surely was a huge factor, but also I think the Mather cabinet with the slightly oversized back board and 4ohm alnico speaker had a lot to do with it.

@TNblueshawk - Yep. I'm not kidding when I say this thing screams. I'm genuinely surprised at how loud 5 watts really is. The amp reacts best when it's pegged.....even clean tones with the guitar volume rolled off (with treble bleed) are glassier. It would be nice to try to achieve those tones at a lower volume.

@Knight of Cups - I gotta say I like the variable feedback. The values of R22 and the pot suit my playing using both the LP and the Tele so far. And by having it on push / pull switch as well gives it that extra little bit of stank.

I've been digging around with power scaling for a while now. Only got turned onto VVR recently. Known about London Power for a couple years. There's also a power scaling kit by Skipz Circuits. Because of the lack of space on the chassis faceplate area, I'm leaning toward Skipz or VVR....I like the notion of having a single pot instead of a pair. (Although I'm mostly aware of why there's a dual pot system w. LP.) So we'll see what the next step is. Of course, I'll have to get over the sacrilege of adding a pcb and a <gasp!> MOSFET.......