Hoffman Tweed Princeton #001

[p2pAmps]

Parts came in yesterday (thanks Doug) So I knocked this one out for a friend.  Pretty cool amp...

[EL34]

Looks good Mike!

[p2pAmps]

Looks good Mike!

Hey thanks Doug...

[Fresh_Start]

With a nice 10" alnico speaker that is a really fun amp to play.

What transformers did you use?
What voltage on plate of 6V6? 

I ask because I had to work to get voltages down to 5F2 levels.  It was worth the effort since I wanted that warm tweedy sound and feel. So was an extra filter cap and choke before the power tube plate node.


Cheers,
Chip


P.S. A small thing but a log taper volume pot instead of linear taper would be a big improvement.

[p2pAmps]

With a nice 10" alnico speaker that is a really fun amp to play.

What transformers did you use?
What voltage on plate of 6V6? 

I ask because I had to work to get voltages down to 5F2 levels.  It was worth the effort since I wanted that warm tweedy sound and feel. So was an extra filter cap and choke before the power tube plate node.


Cheers,
Chip

Hi Chip,

Right now I am looking at 370 on the plates...  The trannies are Heyboers. 


P.S. A small thing but a log taper volume pot instead of linear taper would be a big improvement.

Thanks for the tip

[p2pAmps]

So does anyone think a 12" would totally suck in one of these amps? 

[eleventeen]

Almost like the Flintstones compared to your neat little Princeton Reverbs.

[Fresh_Start]

So does anyone think a 12" would totally suck in one of these amps? 

No, it wouldn't suck. Just need a bigger cab.  However, there isn't enough wattage to really push any 12" speaker I can think of.

IIRC for a brief period on the '50s, Fender put the 5F2A circuit in a cab with a 10" speaker and called it a "Harvard".  I can tell you that a Weber 10A100 is a great match for this circuit. "Warm, crunchy, early breakup. Compressed /fattened at high volume."  Sounds about right. Ted recommended light dope If I remember right (sorry he's gone).

Cheers,
Chip


P.S.  Should've started with "Another really nice, clean build."


One lead dress question - it looks like the junction of the two 68K resistors with the shielded wire going to the first triode grid is unsupported. Is there a turret under there not shown in the photo?

[Willabe]

No, it wouldn't suck. Just need a bigger cab.  However, there isn't enough wattage to really push any 12" speaker I can think of.

Celestion Vox blue, 12"/15w. 

[eleventeen]

Although it does not matter one iota, by custom, the red OT wire should go to the B+ and the blue should go to the plate of the output tube.

[sluckey]

Although it does not matter one iota, by custom, the red OT wire should go to the B+ and the blue should go to the plate of the output tube.

Except when it squeals.

[p2pAmps]

Although it does not matter one iota, by custom, the red OT wire should go to the B+ and the blue should go to the plate of the output tube.

Except when it squeals.

And boy did it squeal! 

[p2pAmps]

One lead dress question - it looks like the junction of the two 68K resistors with the shielded wire going to the first triode grid is unsupported. Is there a turret under there not shown in the photo?

I use shielded cab for the input tied to the 2 68K resistors.  Yes there are not turrets for that but I have honestly never had a problem.  I know Marshalls and some other tie the 68Ks to the board but never have seen it on any Fender yet.  So far it works for me.  Good eye...

[EL34]

That should not be a problem.
Those 68k carbons in that config are pretty stout