Modulator or AF PA output transformers...bigguns...

[N8YX]

I'm thinking about revisiting a design I played around with years ago: 2x 4X150A or 4CX250B in push-pull, running either Class A or AB as an audio amplifier.

So I'm going to need an output transformer which is rated for 3KV+ breakdown on its primary winding, and I'm probably going to run 1800-2100v on the anodes of the tubes. Screen grid voltage and balance will be done dynamically by a separate circuit so I won't need a tap for those.

Secondary impedances of 4/8/16 ohms.

Total power output of the envisioned contraption will be on the order of 2KW (1KW each pair/channel); by going with fewer tubes and higher plate impedance I ought to be able to keep the THD figures pretty low.

Where can I source such a beast? Hammond makes them rated to 300w and 1KV, but this setup requires a stouter configuration.

[NQ6U]

Man, no clue. It's hard enough finding a modulation transformer of any sort these days, let alone one with those sorts of specs.

[mw0uzo]

Get it custom wound. It will be worth the extra and, I have found, that the extra charge for a custom job isn't massive.

[N2CHX]

What the heck are you going to do with all that audio power?

[KC2UGV]

What the heck are you going to do with all that audio power?

That's what has me confused...

Generally, in the audio world, if you are looking for a component that doesn't exist/very hard to find; your design needs to be re-worked. And, that's the assumption I'm having here. Seems like an awful lot of power for audio.

[N8YX]

Max Headroom:

It wasn't just a corny TV show.

;)

[WØTKX]

Jeebus, are your speakers inefficient? You gonna blow up your MagnaPlanars? :neener:

When I was a kid in the prehistoric tube days, I hooked up two identical transformers to get about 450 VAC. Somebody gave me some EL34's to play with...

[K7SGJ]

I'm thinking about revisiting a design I played around with years ago: 2x 4X150A or 4CX250B in push-pull, running either Class A or AB as an audio amplifier.

So I'm going to need an output transformer which is rated for 3KV+ breakdown on its primary winding, and I'm probably going to run 1800-2100v on the anodes of the tubes. Screen grid voltage and balance will be done dynamically by a separate circuit so I won't need a tap for those.

Secondary impedances of 4/8/16 ohms.

Total power output of the envisioned contraption will be on the order of 2KW (1KW each pair/channel); by going with fewer tubes and higher plate impedance I ought to be able to keep the THD figures pretty low.

Where can I source such a beast? Hammond makes them rated to 300w and 1KV, but this setup requires a stouter configuration.

Maybe Marv can help......


9171Oh goody! My illudium Q-36 explosive space modulator

[WØTKX]

LOL!

I have two (toy) Marvins in the hamshack to guard my stuff.