which headphones???

You might try upgrading within the Grado line. My 225's have decent bass response.

Could someone please explain to me why, as previously quoted;

"must be driven by good headphone amp however because of high 300 ohm impedance rating vs 32 ohm rating for Grado."

8 ohm impedance is easier to drive in normal speakers that 4 ohm, so why does it appear the other way round with phones?

My amp, an Audiolab 8000LX has the following stats:

Headphone output:

Output Imp: 330 Ohms
Suitable for headphones 8 - 2K ohm Imp.

Will the Senn 600's be OK with this?
(I am currently using a tired old pair of BeyerDynamic DT 331's - 40 ohm)

Thx in advance,
Josh

Joshcloud ... an 8Ohm speaker impedance is easier to drive for most amplifiers because it draws less current than a 4Ohm impedance, and most cheaper amps are more limited in their ability to drive current than voltage, because high current equals large power supply equals expensive parts.

Now I think that headphones require very little current, but a 600Ohm headphone will require 10 times the voltage of a 60 Ohm headphone in order to drive the same current. In battery powered devices higher voltages are bad news for battery life, and so a small battery powered portable might have difficulty and/or very short battery life driving a pair of HD600s.

In summary the limiting aspect of the design of an integrated amp (current limited) and a portable CD player (voltage limited) are very different, leading to the apparent contradiction in driving capabilities. Hope this makes sense.

Your audiolab amp should have no problem at all with HD600s. I have an audiolab 8000C preamp and it drives higher impedance headphones with ease. My Marantz CD67SE headphone socket will also drive the higher impedance phones with ease.

So I think the HD600s will work with most decent mains powered equipment but might struggle with battery power.

Thx Sean,

Now it is all clear to me :)

I'll add that I changed my Creek 4330R for the 8000LX and am happy with it, sounds far more open and revealing that the Creek and plenty of controlled bass. I found the Creek very "musical" but not revealing enough for my tastes and it didn't have a phone jack (the 5350 does though...???)

I am not 100% sure, yet about the 8000LX as I am listenning through a pair of Kef Cresta 3 floorstanders while I await my new Tweeters for my pair of eBay B&W P4's :)

What I am really looking for is that old magic that my '96 Pioneer A400 amp provided, even if it didn't have much bass (what it had was nicely controlled)...

I am optimistic though :)

Josh~

Josh .. audiolabs are very good amps, but very neutral ... I'm not sure there's much "magic" with them. I have always preferred Cyrus amps as they seem to have more of a beat. Currently my main amp is a Densen B100, and it seems to me to be better than Audiolab, Cyrus and the Naim Nait. I hear that the Densen can be rather fussy of the speakers, though. If you're in the UK then I'd look out for a second hand Cyrus 3 with PSX power supply ... for me that's the best amp you'll get for the money, and probably much more enjoyable than the audiolab, though perhaps less accurate. I used to own a Cyrus 2 with PSX (now its residing at my parents' house) and it was slightly less refined than the Densen, but it had tremendous power and bass.
Unfortunately it has no headphone socket !