ElectroVoice Q-66 amp schematic?

[Enzo]

Mje15032?

Mje15030?

[nosaj]

Mje15032?

Mje15030?

Thank you, but how did you come up with that? Years of experience or .....?

Thanks so much,

nosaj

[Enzo]

Kinda. Those are to me good general purpose high voltage TO220 transistors.

But I went to On Semi web site, under products chose discrete bipolar transistors. In that section I chose audio transistors.

That brings up a ton of transistors. So there is a filter button, which offers things to sort by, not unlike Mouser or Digikey. So I chose package type, and checked the three variants of TO220. That list then I further filtered by checking 250v. I could have chosen other voltages I suppose.

And there was my MJ15032. That is how you get there. I already was familiar with the part from my shop. I use it for cathode transistors in Music Man or PV VTX amps. But I use the selector guide often enough.

I am old school, I have a printed Motorola selector guide book, and in fact have Xerox copies of the most useful transistor pages, and I kept them on my bench all the time. To me that is convenient. But the same information is online in the selection guide I described above.

When asking for a sub suggestion, though , it is really helpful to describe or show the circuit. My suggestion might be influenced by that. Say a driver transistor versus a voltage regulator circuit.

[nosaj]

When asking for a sub suggestion, though , it is really helpful to describe or show the circuit. My suggestion might be influenced by that. Say a driver transistor versus a voltage regulator circuit.

Thanks for the replay Enzo I appreciate the lengths you go to when schooling us.
Referring to your quote above : What criteria differentiates the driver vs voltage regulator circuit? Why would you choose a different transistor in those possible cases?

Thanks,
nosaj

[Enzo]

Oh nothing high tech, but in my mind the Vreg would be far less demanding - it has a fairly steady load rather than processing large signal swings. Or I might determine that they used the same transistor in other places and used it in a Vreg that didn't really need as much voltage simply because it kept inventory down. That sort of thing.