Top Hat Ambassador What spec for OT?

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chopstuck
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Top Hat Ambassador What spec for OT?

Post by chopstuck »

I was going to build an Ambassador - looks like a cool design.

Anyone know if it uses a Fender style 4K OT or a more of a Vox oversized OT . Looking at the 4 6V6's sharing a 150R Rk I'm not sure if it's in class A or not.

Plan was to use a 295-0-295 pt for an AC 30

Will using a Bassman 50w OT be the right choice to soak up the class A heat ?

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JamesHealey
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Re: Top Hat Ambassador What spec for OT?

Post by JamesHealey »

I'd go with a vox over sized my self but that's just me
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Darkbluemurder
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Re: Top Hat Ambassador What spec for OT?

Post by Darkbluemurder »

Fender used to run its 6V6 pairs with a 250R cathode resistor so 150R for a quartet would actually be cooler - provided the plate voltage was the same in both amps.

PT choice is fine with me. With an SS rectifier you should get 380-400VDC which is fine for 6V6s. Heater current would also be in spec.

Any OT with a 4k primary and a power handling capacity of 40W would be fine, e.g. both the Bassman iron and the oversized Vox iron would work well.

Actually I am considering a 4x6V6 build at the moment with a tranny set for an AC30 - PT has 290-0-290 and 275-0-275 HV windings, OT has a 3.8k primary and is suggested for 4 EL84 or 2 EL34 tubes.

Cheers Stephan
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