Powering tubes without transformers

[charlie monroe]

That makes a lot more sense.

In the DIY world, there are a lot of really goofy parts and PCBs offered that in many cases are terrible designs. Also, many do not have any kind of safety approvals and can not pass any kind of global safety approvals.

A common theme of these goofy designs is that they make no sense to professional designers and engineers, and usually do not function the way the "designer" explains it. Surprisingly often they don't even function nearly as well as simpler, more straight forward, more conventional designs. In other words, smoke, mirrors, esoterica and snake oil all come to mind. It's especially bad in the DIY hi-fi world. Even the real designers in that world cringe at some of what's marketed as "high end".

Full point for using the word esoterica

 

[byacey]

To go transfomerless, all you need to do is get a speaker with a 7000 ohm voice coil.

 

[AstroSonic]

To go transfomerless, all you need to do is get a speaker with a 7000 ohm voice coil.

You could get close by wiring the 32 ohm drivers in two 810's in series, for 320 ohms in each cab and a total of 640 ohms for the two cabs.

 

[byacey]

I don't think that would offer a high enough impedance if you are capacitor coupling, because you will also need a plate load resistor which also figures as a parallel plate load impedance.

You wouldn't want the DC plate current going through the speaker voice coils, as this will heat them up and put a DC bias on the coils. There's just no free ride available here, either.

 

[Redbrangus]

There's just no free ride available here, either.

I always thought transformers were the best 'free ride'.

 

[byacey]

I always thought transformers were the best 'free ride'.

Yes, I meant there wasn't any practical way around using a transformer.

 

[Redbrangus]

Yes, I meant there wasn't any practical way around using a transformer.

I imagine this is what everyone who has contributed to this thread thought at the first post. As we say out here in the country, you can't get there from here. It's an interesting thought experiment though.

 

[AstroSonic]

I don't think that would offer a high enough impedance if you are capacitor coupling, because you will also need a plate load resistor which also figures as a parallel plate load impedance.

You wouldn't want the DC plate current going through the speaker voice coils, as this will heat them up and put a DC bias on the coils. There's just no free ride available here, either.

That was not meant to be taken seriously...

 

[Funk With Me]

I always thought transformers were the best 'free ride'.

Until you have to carry it.

 

[Basslice]

I imagine this is what everyone who has contributed to this thread thought at the first post. As we say out here in the country, you can't get there from here. It's an interesting thought experiment though.

I agree. However, if someone could figure it out, it would be revolutionary.

 

[byacey]

I agree. However, if someone could figure it out, it would be revolutionary.

Yep, but you can't break the laws of the universe for personal convenience.