I asked the question and they answered that in their own testing they didn't hear a difference.
No reasoning was given.
I went for the XS though, just in case :-)
There are two current models: the CS300 and the CS300XS. The latter version has various upgraded components.
The CS300X is discontinued, and has been replaced by the CS300XS. The amplifiers are identical (I believe), the only difference being the tubes used.
In terms of headphone use, Leben told me that there is no qualitative difference between the 300 and the 300X(S). The sonic differences lie in their speaker output.
my guess is that Leben is simply referring to the 15W the CS300X/S outputs from the speaker taps, as opposed to the 12W from the CS300.
I feel (to my ears) that all of the flagship headphones (except maybe the Audeze) benefit from a warmer amp. So I would worry about any amp that is bright or even neutral.
If you read any write-up here of the major top phones, brightness is always mentioned (and I agree with this assessment from my own listening).
It seems like the amp and phone makers need to cooperate a little more.
I mean, 10 years ago, the Senn 600/650 was the standard must-own dynamic, but those days are gone, and unless the phones start warming up, I'd get an amp to compensate for that.
(I have a B52.) I kind of miss the little toggle switch high-frequency filter Tyll put on the original HR Max.
OK, maybe the LCD2 and the Edition 8s are not especially bright, but even those benefit with hyped up recordings (and there are way too many of those).
Yes it is. I use the leben 300X with stock (mullards) tubes and HD800 and also power my proac tablette reference 8s in an nearfield setup. Both sound amazing. And great for me because my room is quite small.
First of all, outstanding review. I've been drooling over an Apex since it was introduced. It is at the top of my wish list right now along with some HE-6's. I can dream right?
Who, me? Yes, books are how I make my living now. Thanks for asking.
If you don't mind saying what type of books? I'm an avid reader and am always on the hunt for something interesting.
Innerspace--great review. Could you please comment on the 24-step attenuator with the phones you used and whether you could get a good level? I notice that the B52 uses the same attenuator (the DACT one, so I assume it's the same one).
Thanks. The gain architecture seems to work fine with the stepped attenuator. I'm usually four or five clicks up and the steps are subtle enough - I don't find myself wanting an in-between setting anywhere.