Amp damping factor?


OK need some technical info. I was told by a reputable source that I should buy an amp that had a high damping factor >100 and preferably closer to 150-200. In looking at this in the specs for many units it seems this might be over-rated. I have been looking at some vintage Mac gear and their numbers are like 10-40? Is that an age thing and modern equipment is just that much better? Or is there a tradeoff I dont know about?
joekapahulu
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
Pauly - I agree. Specifications are very flexible and often misleading. Amplifier (and any other) design is a series of compromises and when you see an amp with exceptionally high DF and extremely low THD something else has to give - the sound.

Joekapahulu - I wouldn't pay too much attention to DF. For instance Atmasphere MA-1 amps have DF<1 (tube amp without output transformer) but sound great according to 6Moons review ("gigantic imaging, excellent dynamics, frequency extension and potent music-making").
An amp doesn't have a damping factor. Damping factor is the ratio of the rated impedance of the loudspeaker to the source impedance.

The convention is to report Damping Factor into an 8 ohm load - so for pratical purposes one might say that power amps do indeed have a Damping Factor.

It can be over rated as the woofer drive motor and mechanical as well as acoustic suspension can play a much bigger role. A high damping factor amp is not going to fix a badly designed speaker with low cost drivers with cheap (small) motor - that will be putting lipstick on a pig.