How to do Single center tap/bridge regulated supplies?

ChuckT

Member
2002-11-29 5:41 am
HK
Hi all,

I have a broken amp with a good preamp section and I want to replace the amp section with a gainclone.
It has a huge tranny with +/-40AC and only one center tap. This gives +/- 55V DC output. Is there any good circuit to drop the voltage down to below 35V?
Note I don't want to take apart the tranny to get 2 CT.

I had looked at Pedja site (Thanks Pedja for the info) and there is a nice discrete circuit. But I don't know if it will work with single bridge +/- supplies.

TIA.
 

ChuckT

Member
2002-11-29 5:41 am
HK
Thank you, guys. I only know the basic electronics, so a switch mode is a bit out of the question.

The secondaries are 94Vct (1A), 74Vct (3.75A) and 15Vct (1A). The 15Vct is for the preamp section.


I wanted to use the LM3875 with +/-35V.
Guess I will use the LM3886 with +/-45V. Now that's only a 10v drop.

Can anybody tell me if Pedja discrete supply work with some modification. thanks.
http://www.pedjarogic.com/gc/supplies.htm
 
Hypex modules can theoretically run on 42v

ABS Max continuous voltage for general audio amplifier applications:
LM3886TF, 37v
LM3875T, 40v
LM1875, 31v
And, at slightly beyond this point you can use fans and/or add about 4 ohms resistance in series with the speaker output.

These maximum voltages aren't something to do on purpose, but rather. . . just a note on "where" that "too far" might be.

Also, too-high voltage necessitates higher powered input or higher gain setting, and at some point either can be a mess.

Hey, is that 15v a single (15v AC) or is it a 15vct (as in 15+15 AC)?