Amps have alot of measurements which aren't always given as specifications.
one of which i believe is slew rate.
I don't have a full understanding of it, but i believe it has to do with the amplifier's ability to swap polarity, which affects control.
Bruce, can you give an explanation for us, it'll help to show the benefits of a quality amplifier

Slew rate is the voltage rate of change as a function of time. It is the fastest rate at which a device can change the level of voltage, measured in volts per (micro)second.

In a hi-fi audio application, the slew rate doesn't have to be all that fast (relative to some other applications), because of the limited bandwidth required.

http://www.amplifier.cd/Tutorial/Slew_Rate...te/SlewRate.htm
http://www.amplifier.cd/Verstaerker/Wald_u...e_bandwidth.htm

[ December 22, 2003, 13:36: Message edited by: Bassaholic ]

so slew rate only really applies to data transfer, due to the limited frequency range of audio amplifiers.
if the slew rate was ridiculously low it could harm SQ.

regardless, the faster the slew rate, the mor accurate the amp is?
even if it's mostly beyond our hearing range...

Remember, accuracy is relative to your ears - there is no point being accurate to ridiculously high frequencies when you cannot hear it. Any extra bandwith is simply unneccesary and irrelevent.

Remember, when engineering an amplfier, the aim is to make the perfect compromise - and providing any extra detail that you will not hear will not be a perfect compromise - why bother overengineering something if it doesn't have any real benefit?

I have a very simple rule about slew rates, and that is, cheap amps wont supply this spec, and so anyone who does, has made a darn good amp. So if slew rate is spec'ed then you are looking at high end amp period
peace
Cyberpunky

Cyber, I wish this was the truth but it isn't. I have never seen specs for a car audio amp that were done properly, all specs are either lies or completely uselss. There are defined ways in which to test specifications and without the test metod stated with the spec it is completely useless.

Exactly...

I hear you K-dog and agree but in my eperience any company that bothers to do a slew rate spec regardless of method used, is so far above the cheaper stuff that doesnt even have a freq speced for output is "usually" one of the better amp makers.

I wouldnt buy an amp on wether or not it qoutes slew rates but I would buy an amp that states a slew rate over an amp that doesnt mention thd or freq range max power is over,

Anyway slew rate is rarely specified and so if a brand can be bothered quoting it then I reckon your a step ahead of the marketneering barnds
peace
Cyberpunky

Yeah, its probably a reasonable assumption to make. Lets hope the marketers aren't reading this thread. lol

intersting stuff

i aways thought that slew rate was just a function of frequency response (bandwidth). The higher the bandwidth the better the slew rate and vice-versa

i have been having a very quick look at amp design and it seems like the standard class a and a/b are bandwidth limited to 150khz and below due to high frequencies resonance. Most of the amps ives seen reviewed are around the 100Khz range.

self oscillation and amplifiying out of band noise is a major concern for amp designs. The main object seems to be low noise, a flat frequency response to 20Khz and also a flat phase response to 20Khz.

all in all i cann not see the benefits in a high slew rate amp unless if was designed for data communications rather than low bandwidth audio tansmission/amplification

Just looking through my Zapco manual here, it says slew rate is often reffered to jokingly as "damping factor" for tweeters.

HAHAHHA

my cadence Q2000 amp quoted the slew rate, cheap amp...