High power single supply amplifier?

Jay

Banned
2003-02-11 9:02 am
Jakarta
Why is it not common to see high power amplifier with single ended power supply? I have a big transformer (around 7A) with 14Vac or about 20Vdc that I want to use for as highest wattage amplifier as possible. The front end can be driven with higher rail voltage if necessary. Is there such amplifier design somewhere?

Thanks
 
+/- Rails...

An amplifier running from a single-ended supply must use an output coupling capacitor because the output must be at 1/2 Vcc for the amp to operate in a linear fashion. Dual amps get to run the output at 0 V and, naturally, have no need for an output coupling capacitor. Capacitors can limit low frequency response and electrolytic capacitors can cause distortion by non-symmetry leakage/impedance issues.
 
You could use a bridged amp to get higher power from a single supply, or make a dual supply with your transformer as shown below.
 

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Why is it not common to see high power amplifier with single ended power supply? I have a big transformer (around 7A) with 14Vac or about 20Vdc that I want to use for as highest wattage amplifier as possible. The front end can be driven with higher rail voltage if necessary. Is there such amplifier design somewhere?

Yup, right here: Zeus Amp

That'll get around the need for a dual, +/- supply.

Multiplier! That's a good idea, thanks. I will use the 20V-0-20V for Quasi NBIP using 4x or 6x 2N3773 per channel.

It's not a multiplier. It's two back-to-back half wave rectifiers running off the same xfmr. You're looking at a whole essssssss-load of problems: DC core magnetization, and making the filtering job twice as hard as it would be with full wave rectification.