amplification dependency on supply voltage

[Othello]

I have a power amp mono block which calls for a 60V supply voltage.
I don't have that available and run it on roughly half that supply voltage.

I don't need much amplification to start with and wouldn't mind running the amp always like this but I wonder how the specs change with a change in supply voltage. I am thinking that as long as all the biasing circuitry is happy all that would change is that the amp would start to clip earlier.

But I wonder and wanted the opinion of experienced folks.

Uwe

 

[Sceadwian]

As you said as long as the biasing circuit is happy you should be fine, but as you said it'll clip at a lower 'volume' level. One of the benefits of this is the circuit should really last longer as you're barelly loading it compared to what it's capable of.

 

[audioguru]

If you cut the supply voltage in half then its max output power will be about one-quarter.

With a 60V supply, its full output into 8 ohms is probably 47W. With a 30V supply, its full output into 8 ohms is probably only 11W.

It depends on the design whether the biasing will change. It might have crossover distortion when it has only a 30V supply.

 

[Othello]

What do you mean by crossover distortion?

To clarify, this is a monoblock, to be part of a bi- or tri-amp system.

Uwe

 

[audioguru]

Google has many articles about crossover distortion that is caused when push-pull output transistors do not have enough bias voltage. There is a "dead" part of the waveform where one transistor crosses the signal over to the other transistor.