Importance of Damping Factor and Current for amps

In addition to the good points that have been made above, it should be kept in mind that extremely high amplifier damping factors are meaningless in typical setups, because from the woofer's perspective damping is also limited by the resistance of the speaker cables and the resistance of the inductor in the crossover.

A 10 foot run of 12 gauge speaker wire, corresponding to a 20 foot round-trip for the signal, will limit the damping factor to about 250, even if the amp's damping factor is infinite. Crossover inductor resistance is often much more significant than even that, and I believe in many cases will limit the damping factor to well under 50.

Regards,
-- Al

I hope this thread is read by many members.

About a month ago I had a spirited discussion with a customer who insisted on purchasing an amp from me with a high damping factor.

The amp I recommended would have been a terrific match but the gentleman insisted differently based solely on the damping factor.

In any case, Ralph, Simon, Jallen, and Stan make good points.

In general amps with high current capability will deal with difficult , low impedance loads better, but , as noted, there is no single measurement or even sets of measurements that will tell you what a speaker amp combination will sound like. I have found it amusing how often you see the sound of a speaker or amp described by itself when in fact there is no such thing as the sound of a speaker except as driven by a particular amp or of the amp except as heard through a certain speaker. As a dealer I always suggested selecting a speaker first as it is considerably easier to find an amp that will work well with it than it is to find a speaker to match an amp. In the first case you know what the needs are, in the second you have potentials that could match many different speakers in different ways.

Thanks to all who responded so far and provided a good range of opinion It should be interesting to hear Hooper's impressions about the Pass amps.

High damping is overrated. Some amps with high damping factors have no musical bass. The notes are all pinched, and thumpey, like a car audio-hell on wheels. Tubes have damping factors in the 10-15 range, and can be quite stunning. A good match is critical. jallen

High dumping factor, IMO, is useless as I never know will it help or not.

There are some amplifiers with 5000 - 6000 dumping factors which cannot handle difficult load.

On the contrary, high current delivery , is always, always useful and its difficult for me to imagine situation where high current delivery can hurt...

Also, when I say "high current delivery" I mean not over period of a few milliseconds as its only marketing.

Finally, high wattage does not mean that this amp is with high current delivery. Good example is bridged solid state amp e. g. Spectron stereo versus monoblock amp.

This is not a universal truth by any means! If the speaker is over-damped by the amplifier, you will get **less** bass and no definition!

Some speakers want almost no damping and others need some; no known speaker needs over 20:1.

There are two design paradigms for amps and speakers that compete in the high end audio world. You cannot mix equipment from opposite camps as it will result in tonal anomalies- this is the equipment matching issue you hear about so often. For more info see:

http://www.atma-sphere.com/papers/paradigm_paper2.html

I'm going to find out for sure on Saturday, as I’m going to compare my Coda S12.5 to a pair Pass Aleph monoblocks. The Coda has far more power (125 watts vs. 30) and a very high damping factor, so we’ll see if it controls the bass better on my friend’s Vandy 3As. My other friend, who suggested the shootout, seems to think it will.