Lab Gruppen Wattage Question?

[pete10uk]

Hi All

 

Just a bit of a question.

 

I'm just specifying a job, the customer successfully uses Lab Gruppen C20:8x amplifiers in other locations, so has a bit of an liking to them, however the spec sheet states 8 x 250w @ 4, 8 and 16 ohms as well as 70v. I was expecting a different wattage dependant on the resistance. Dose this amp do some clever monitoring and adjustments to achieve 250W or am I missing something.

 

Cheers

[DrV]

Yes, they are smart. They use something they refer to as Power Average Limiter (PAL) to adjust the power. It's in the spec

 

http://labgruppen.com/view-model/c-series/c20-8x?page=spec

[Chappie]

You'll find that many modern class D amplifiers, especially 4 or 8-channel versions, do not follow the pattern of output power that you would normally associate with linear class (A, A/B, H etc) amplifiers.

[timsabre]

You'll find that many modern class D amplifiers, especially 4 or 8-channel versions, do not follow the pattern of output power that you would normally associate with linear class (A, A/B, H etc) amplifiers.

This is because they tend to have more "smart" features though, it's not anything to do with it being a class D amp. Power output from a class D amplifier output stage follows ohms law just the same as a linear amp output stage. The processing stage is designed to adjust the signal level to keep the output power constant for different load impedances.

[pete10uk]

Answers a fer questions, thanks.