Supply for Class D amplifier not split?

[eem2am]

Hello

If there is a class D audio amplifier that runs off +24V, -24V

-Can i simply supply it with 48V instead?

[alexcp]

No you cannot.

[Andy5112405]

How many threads are you going to start with the same question ????

That's three so far.

[ssanmor]

No, you cannot, you need a ground reference.
If you need a +/-24V PSU just ask us (www.coldamp.com)

[hilli_billi]

Why not,
IRF shows in AN-1164 how it can be done.
Wants someone to try it?

[ssanmor]

We have done many experiments about that, and the results were not good. Even when using an active bleeder the symmetry obtained is not suitable for mid to high power and low frequencies and can lead to many problems. Leaving apart that the transistors will dissipate quite a lot of power in these applications, ruining the efficiency of the switching power supply (if used) and Class-D amplifier.
Virtual grounds (even using opamps) are not a problem for small signals and are widely used, but for power stages they are not very recommendable.

[runebivrin]

Or use two amps in bridge mode. That leaves the ground mostly signal level.

[Pafi]

In my PC amplifier I also use single supply splitted by two capacitors. The DC voltage is set by the amplifier via sub speaker. No need for dedicated active bleeder, neither bridged amp. The only thing needed is properly controlled output voltage: it's reference potential is composed from (positive rail+negative rail)/2 at DC, and output GND at AC.

(This amp is Class AB, but it makes no difference.)