What would you choose between Zener and IC regulator for the preamp section and why? I read that zener regulated power supply is unstable, but then, would that make the amplifier feel more "organic" and "touch responsive" compared to the IC regulated one.

My goal is to build an amp with TL072 or TLE2072. The power supply would be +-15-18V. I want it to be as clean as possible, with as low noise as possible, because I will be using it for jazz. So, the greatest concern for me for now is how to regulate the power supply for a maximally clean and quiet preamp, but then again, I don't want a sterile Hi-Fi amp sounding either.

I am thinking about using a choke for the power supply of a TDA7293 amp as a means to filter out all that DC ripple. The amp would be running at +- 32-36 Volts. What would be the specs of the chokes that I need?

Also, can I use chokes for the preamp section, which is built around two TL072 chips, or the ones used in the power amp supply would suffice?

After awhile, I am thinking about building a new solid state amp, that would suit my needs. The reason - my beloved tube amp is oh so gentle, and go into rattling snake/tamburine mod after a year or so! So, there are three paths I'm considering:

1. Building the "Blackface" preamp from RED circuits and  making its power supply switchable from 30 to 12 volts.

2. Doing the same thing with ROG's "Umble" preamp.

3. Maybe even doing them both as switchable channels.

My questions:

- What are your opinions on these circuit designs?

-  Can I increase the Umble's power supply, without doing any harm. Also, I read that the circuit is a bit noisy, is there a way to fix that?

Hi! Until now, for my projects I've used mostly pre-designed PCB's. Lately I've been thinking about building some stuff on a perfboard, so my question is - should I pay attention where I lay the parts regarding things like oscillation etc.? Can I just replicate the schematic on the perfboard, for example, on the top I put the +V, on the bottom the ground, on the left side Input and on the far right the Output?

I've put this question in  "Preamps and Effects", but the same goes for other circuits like power amps etc...

Hi! This is not exactly a schematic question, but maybe a question related to a part of schematic, Anyway, I apologize if post the thread on a wrong place.

I need 15V regulated dual supply, and I've decided to go with Zeners instead of IC regulators. So I have two questions:

- what would be the value for the resistors in series with the Zener diodes?
- I'd also like to have switchable 7.5V dual supply; can I use some DPST switch which would switch on and off the 7.5 Zener diodes in parallel with the 15V ones, and also, what would be the resistor value for the 7.5 diodes?

The transformer would be +-22V or +-18V.

Thanks in advance!

Hi! I found this interesting circuit : http://www.redcircuits.com/Page120.htm, which I would like to use as a preamp for a power amp with TDA7294 chip. But the power supply needed for TDA7294 is dual, and for the RED circuit is single. Is there any way to convert the RED circuit into a dual supply, and how?

Ok, so first of all hello to everybody here  8| So I have these chip and transistores spare in my junkbox and I thought I could upgrade my  TDA2030 10-15w practice amp  that I built some years ago. Now, I have this schematic for TDA2030+BD243A/BD244A current boost or something hybrid amp design that would suppose to deliver 40W into 4Ohm load at +-22V. I don't have a scanner so I can't post the schematic right now, but maybe someone could tell me if I could just use TDA2050+BD249C/BD250C instead or would I have to change the values of the other parts as well? For the power supply I have two transformers to consider: 2X18(center taped 36v?) and 2X24 (not quite sure about Amps though, the 2X24 one is over 2A i think) so would those be suitable, could all that work, and how much output would I get out of it? Is it worth bothering or should I just swap the TDA2030 with TDA2050. For the TDA2030 amp I used 2X9V transformer and that was too much for the chip so I put two 9V zener diodes to have exactly 18v for the power amp section. For TDA2050 I'd just remove those diodes so I guess it would work fine for some 25w amp into 8Ohm load. So what do you guys think?