nm2285 said:
I have a pair of Sennheiser HD590s (120 ohm) and was considering a headphone amp for them. I enjoy the way they sound now straight from my laptop and was wondering how much of a difference an amp would make. Also, do more expensive amps really make that much difference or is it similar to home audio where the amps don't matter nearly as much as the speakers?
Let's get some facts straight so that the situation is looked at from an objective standpoint.
Headphone.com, as referenced by another user, I can not recommend using for any sort of information purposes. They present facts mixed in with fiction: you can't trust them. They appear to typical hi-end audio minded people.
There is nothing inherantly superior, audibly, from a mega-buck headphone amp that can not be acheived from a much cheaper version has been proven to exist. The main reason to buy a mega-buck headphone amplifier is for cosmetics, imagination(you think it sounds special) or just to show off to audiophile friends.
The real issues for a headphone amplifier purchase, after you know what you need, should be:
-Does it have sufficient gain(output level vs. input level) for your headphones and source combination?
-Does it have an audible noisefloor(hiss) within normal volume settings?
-Does it have a crossfeed acoustic filter(some people need this to enjoy headphones, but I don't personally like crossfeed)?
-Does it meet your requirement for portability?(Size, power sources, etc..)
-Does it have a switchable 0/120 Ohm output impedance? (Some headphones were expressly designed to work with a 120 ohm source impedance, it will affect frequency response slightly--you can achieve the same thing by using a 120 ohm resistor in line with the headphones if the amp does not have the feature built-in)
As for an amp improving your laptop output -- that is entirely dependant on the specific headphone/laptop sound section combination. Some headpone outputs may have severe distortion that approaches audible levels with some very low impedance headphones. You can fix this by using a resistor in line with the headphones, but the soundcard will have to produce higher voltage output in order to compensate, and many will not have the additional voltage available so it will end up being not loud enough. Some audio outputs have audible hiss and other noises; the only rememdy in that case is to use a different soundcard.
-Chris