I was bored - another YouTube clip

I was playing the first amp I ever built (a modified 5F1 tweed Champ circuit) and realized how ridiculously awesome it sounded! Unfortunately the crappy camcorder mic is terrible.

Mods:
15 watt OT and a Bright switch as well as a switch for putting a cathode bypass cap in the preamp or taking it out (the original schematic AND layout do not have a bypass cap on V1). Right now its got a 6L6 power tube in it (I have a switch in the back to change cathode bias resistor for 6V6's or 6L6's/EL34's).

Anyway, even through a P15N reissue Jensen 1x15" its got as much chime as my AC15/AC30 head through 2x12" Celestion Blue AlNiCo's. Its got plenty of tight bottom end as well. Its about as loud as my 5E3 tweed Deluxe.

Hopefully the beautfiul chime and complex swirl comes through - if not, at least you got to do something for 5 minutes :smile:

1LWZvMW1s0E

I was playing the first amp I ever built (a modified 5F1 tweed Champ circuit) and realized how ridiculously awesome it sounded! Unfortunately the crappy camcorder mic is terrible.

Mods:
15 watt OT and a Bright switch as well as a switch for putting a cathode bypass cap in the preamp or taking it out (the original schematic AND layout do not have a bypass cap on V1). Right now its got a 6L6 power tube in it (I have a switch in the back to change cathode bias resistor for 6V6's or 6L6's/EL34's).

Anyway, even through a P15N reissue Jensen 1x15" its got as much chime as my AC15/AC30 head through 2x12" Celestion Blue AlNiCo's. Its got plenty of tight bottom end as well. Its about as loud as my 5E3 tweed Deluxe.

Hopefully the beautfiul chime and complex swirl comes through - if not, at least you got to do something for 5 minutes :smile:

1LWZvMW1s0E

Hey JC, Willing to share the schematic/layout on that? I am jonesin to build a champ, which will likely keep growing into a princeton or harvard, but just need to get my hands busy doin' something...

Its exactly the same as a normal 5F1 except I used 1N4007 SS rectifier diodes instead of a 5Y3 and I think I used 20uF filter caps.

For the cathode switch I believe I used a 5uF or maybe 10uF and for the Bright switch I only used a 250pF (though I am leaning towards a 100-120pF now).

For the "bias" switch I have a 470 ohm cathode resistor for 6V6's and a 250 ohm for 6L6's/EL34's

I checked my transformers out for you and I actually used used a Hammond 270DX (which only spits out 225DC, which when SS rectified is a low 315 B+) and a 10 watt Hammond 125DSE OT (using the 5k tap for 6L6's and the 10k tap for 6V6's for the impedance/speaker switch on the rear).

Wow, that 10 watt Hammond OT is friggen LOUD! Especially considering I'm running "brown" with low 315 B+ voltages.

Sweet! I just got a harvard OT and hope I may have a PT laying around, or that I can get my hands on quick, as I have about a month of sitting on my thumbs after my treatment finishes up next week and I will need to be busy. So why not build an amp to go with the tele I am finishing up?

I am just tossed up between a 5F1 or an AA764. The Harvard OT will be good for either, I think, but I have to nail down the PT and a few odds and ends...

By the way DUDE YOU ROCK!!!!!

I am just tossed up between a 5F1 or an AA764. The Harvard OT will be good for either, I think, but I have to nail down the PT and a few odds and ends...



I've gotta admit - the BF/SF Champs are my favorite Champs. Sure the 5F1's are rude, but they're also dark and less flexible than AA764's.

5F1's take Rangemaster treble boost pedals really well. AA764's are nice for home volume cleans and take all sorts of pedals very well.

I am just a humble noob trying to learn at the feet...

mostly I just know what I like to hear. Classic tones mostly. Tended towards fender until I discovered the Vox pathfinder 15, then 10 (which I now own), but the new kid that caught my interest is the egnater rebel 20. Just seems to do it all! I just can't afford it... so I will build...

Gotta love those Jensen speakers

Like butter! Now I want to build a modified 5F1. :mrgreen:

There's a thread about building a 5F1 or AA764 (BF/SF Champ) in the Amp Central Station Forum here from one of our TDPRI brothers in Turkey, check it out. I posted some ideas for the OP to use for negative feedback switches and tonestack lift switches on a BF/SF Champ circuit.

The BF Champ has a tonestack (resulting in gain loss) and more negative feedback (resulting in more headroom). Using 2 switches (1 to lift the tonestack and one to lift the NF) will not be an exact "5F1 conversion," but will go from BF/SF to a sort of "tweedish" Champ vibe... plus it uses only a few extra parts (two resistors, two pots, three small caps, and two switches) and can get you a lot more versatility.

From dark and dirty tweed Champ to cleaner and tighter BF/SF Champ with only a handful of parts... couple that with a 10w OT, a cathode bias switch in the back, and a 6L6 and you can get a louder Champ or a swap in a stock 6V6 Champ with tighter bass (tighter from the 10w OT).

Very cool. Now I wanna go back in and "de-stock" my '67 Champ...

Is the cyclops car really your car?

I had a '97 Camry (green, no less) that was beat to death before I sold it (200K, original struts and such) so it made me laugh, and brought back memories.

Very cool. Now I wanna go back in and "de-stock" my '67 Champ...

Is the cyclops car really your car?

I had a '97 Camry (green, no less) that was beat to death before I sold it (200K, original struts and such) so it made me laugh, and brought back memories.



Yep. Still running.

Great clips the amps sound very nice!