Transformer Question...

[v00d00blues79]

I have a set of the TW Heyboer tranny's and i'm thinking about using them in a ODS build. Anyone have any suggestions or recommendations? The PT 300V AC side should rectify to 420 or so, which should be enough to run a quad of 6V6's and the OT should be able to handle them unless i'm mistaken. Also, which primary tap would be recommended? the 5.2k or the 6.6k?

Thanks,

Andy

[Luthierwnc]

I'm not sure you will see 420 on the plates. That is the theoretical voltage. When all the tubes are in you are probably looking at more like 400VDC. That is a good voltage for those tubes but they will sound a little browner than in a DR so adjust your components accordingly (i.e. slightly higher voltages on the preamp plates and slightly smaller caps to protect the low end).

The impedance for a quad of 6V6's is around 4k so go with the smaller Z-out or make it switchable if you have a half-power mod.

That should make a killer amp, BTW. Speakers will matter a lot. Four 6V6's will give you large tube power and their own sweetness but you won't get the bottom-end of 6L6 variants. Make sure your speakers are firm on the lows. I'll bet that build would sound great over a Chicago 15 or (and this is a guess) one of the new Eminence Big Bens. I built a 5F8-A amp maybe ten years ago using 4 6V6's. The guy who bought it put it over 4 10's and it really delivered.

Skip

[v00d00blues79]

I'm a real big fan of 4x10 cabs and 1x15 cabs. I was thinking of doing a 4x10 for it. I am going to try and adjust for the lower voltage from the PT so that the preamp voltages stay the same, or at least in the same ballpark. But back to my original thought, would the TW OT, which is rated at 40w, be able to handle the quad of 6V6's or am i going to have to go with another tranny?

Thanks,

Andy

[Bob-I]

I'm a real big fan of 4x10 cabs and 1x15 cabs. I was thinking of doing a 4x10 for it. I am going to try and adjust for the lower voltage from the PT so that the preamp voltages stay the same, or at least in the same ballpark. But back to my original thought, would the TW OT, which is rated at 40w, be able to handle the quad of 6V6's or am i going to have to go with another tranny?

Thanks,

Andy

I think you'll be good with that xformer. You might be seeing 45 watts but it should handle it just fine.

[v00d00blues79]

Running it on the 5.2k Z-out, would that be good middle ground to run a half-power switch?

Thanks,

Andy