Amp damping factor?

Another aspect of loop feedback is that all amplifiers have a delay time- the time that it takes for the signal to propogate from input to output.

What this means is that the feedback signal will always be a little late getting back to the input of the amp. As frequency goes up, the problem gets worse as the propagation delay of the amplifier remains constant (in effect the feedback signal is progressively later). At very high frequencies this can cause the amplifier to oscillate if not treated properly in the design.

The result is a sort of ringing effect in the amp, which plays a role in odd-ordered harmonic enhancement. Keep in mind we are not talking about very much distortion; hundredths of a percent is all it takes to be audible.

??

An amp doesn't have a damping factor. Damping factor is the ratio of the rated impedance of the loudspeaker to the source impedance. In other words, you can only calculate a damping factor when you have a speaker amplifier combination.

What you are looking for is an amp with a low output impedance which then results in a good damping factor number.

Regards
Paul

http://homepage.mac.com/tlinespeakers/vaughn/downloads/Damping-Factor.pdf

An interesting article on damping factor.

John C.

"An amp doesn't have a damping factor"

Pauly - You'll often find DF in amps' specifications. "Having" DF simply means amp has that many times lower output impedance (at given frequency) than assumed 8 ohm speaker. DF is a measure of output impedance - hence amp "has" DF.

"What you are looking for is an amp with a low output impedance" - not likely to find in specifications, look for higher Damping Factor instead.

Kijanki – an amplifier that has a DF rating is probably something I'll pass on. When specs are written by the marketing department, one never knows just how creative they’ve been.

Regards
Paul