audio-talk

Am I missing something

You may be missing what choke input means, its not just a power supply with a choke in it.

Yes, remember the following cap is a short circuit at AC, so the choke has the full AC voltage across it and current through it. MJ covers it well.

pre65 wrote: ↑

Tue Nov 12, 2019 6:50 pm

Nick wrote: ↑

Tue Nov 12, 2019 6:38 pm

A bit like the way "Delhi belly" is used to describe the after effects of too much curry.

Yes, I get that, but the analogy would be using "Delhi Belly" to describe the result of having Pie And Chips.

Over time the specific meaning becomes more generalised ?

I give up.

A bit like the way "Delhi belly" is used to describe the after effects of too much curry.

Yes, I get that, but the analogy would be using "Delhi Belly" to describe the result of having Pie And Chips.

RhythMick wrote: ↑

Tue Nov 12, 2019 6:30 pm

Not sure I'm following the concern, 60mA well under 200mA rating?

Yes, but choke input is much harder on a choke than cap input.

Are there any disadvantages of this mosfet follower design Tempted to say transistor ear but... As the linked article says, the changing input capacitance may matter, but can be reduced by having a large d to s voltage across the mosfet. Also, theer will be distortion introduced by the source follo...

not necessarily accurate.

That's all right then

transistor ear

Err, that sort of proves that whatever it is you don't like, its not transistor ear.

Yep, the red spot is power dissipated, voltage * current, if one is low the other needs to be high.

I thought the "Power Driver" was just a mosfet source follower.

Thanks Mike - might be worth a try. This bit is on the PCB so adding it could be a touch fiddly. I'd just bung it across on the track side. :D Sadly it's a double sided PCB with insulated tracks... :( I think Mike means the side without components. You can scrape the resist of the tracks if there i...

What frequency is the oscillation at?

Already asked that question.

Ok, so you are running it with 0v bias then, so you could do that again.

And was the cathode connected directly to ground?

I think it was negative, what bias are you running at the moment?

A) The input direct from preamp ? Yes, but you will need to add a adjustable bias to the input, whatever DC voltage is on the input will be on the output, thats how it works as a A2 driver. Cap coupler your preamp input to that. B) The output to 833a grid ? Yes And, what would be a good way to conf...