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Recommend SE OT

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12/24/2004 9:43 AM
Daver	Recommend SE OT I'd like to build a 2X6V6 SE amp. Could anyone recommend a good OT? Should the primary impedance be about 4K? Allen Amps makes one, but I'm not sure if it'll handle two tubes as opposed to one. Thanks! Daver

12/24/2004 9:36 PM
rooster	A Heyboer 18W OT from GDS Amps. I like them a lot. Lots and lots. rooster.

12/24/2004 9:37 PM
rooster	OOPS! Didn't see the "SE" part... On my 2x6V6 SE amp, however, I use a Hammond 125ESE with a 350V B+ and it seems to hold up fine. Not bad for about $40. rooster.

12/24/2004 9:38 PM
Marc	Re: Recommend SE OT Daver: the Hammond 125 ESE is good. Angela has them for about $33. Marc

12/25/2004 10:25 AM
Daver	Thanks to both of you for the help. Looks like the Hammond is it so far. Anyone else have any experiences with SE OT's? Daver

12/25/2004 12:35 PM

Use the Angela universal 125ESE. It has relatively poor bass response which is what you usually want for a guitar amp SE. If you use a tranny with wider bandwidth then you will immediately have hum problems because the residual AC ripple in the OT primary will make it through to the speaker. This is not a problem with PP because any ripple present will cancel out due to the humbucking nature of PP.

For full range OT's in SE you will almost certainly need a pi filter for SE HV since filter caps alone will not make the voltage clean enough. In sum, use a cheap OT to resolve this problem.

Impedance for single 6v6 should be 4-5K.

For 2X6V6 it's half that being 2-2.5K

12/25/2004 4:31 PM
Daver	Thanks, FreeWHEEL. What are you guys using for power transformers? Daver

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