Best Pass Labs Amp with B&W 800 Diamonds?

Wouldn't the 1000.5 be the best?

I owned 5 different Pass labs poweramps, and in the past I owned the 800 S from B&W. I would go for the 600.5 in your situation. You need a paired set of mono's. The extra current will give you a better result than the XA series. I owned 3 different XA.5 models as well. The Purist Audio Limited Edition is one of the best powercables for Pass. I tested many on Pass Labs for over 6 years of time. I do consulting in sound7vision and I work in this world for over 17 years of time.

Can you post what are main diff between XA160.5 and X250.5. I own X250.5 and found fail to power B&W801d.

Mimskev hi, look at the phase (dashed) v Impedance (solid) at 60hz 4ohm, this is where the two meet, now this is not a 4ohm load, it could be as low as 1ohm and this is where the bass power/control is required. Also up high at 8khz.

http://www.stereophile.com/content/bampw-800-diamond-loudspeaker-measurements

An amp to drive these nasty loads with comfort ease and good amperage, should be able to almost double it's wattage from 8ohm to 4ohm to 2ohms eg: 100w 200w 400w

This sort of amp needs to have bi-polar output devices, not mosfet as I belive the Pass amps you mention are. Sure they will work and sound good but at these points 80hz and 8khz an amp with bi-polar not mosfets will sound better.

Cheers George

Mimskev: Passive biamping is no big deal, it's not hard. Active biamping with an external crossover, is a bit tricky. Either way, Pass Labs has you covered as they make active crossover units.

Just curious, did you end of bi-amping and are you happy?

Sorry for the slow response! I spoke to the guys out at HiFi Reno and got a great deal on a pair of brand new XA160.5s. Love how they sound!

They were willing to work with me and even let me try the XA200.5s, but once I had the XA160.5s I was hooked...

One word of caution, these amps get HOT! They can easily heat my media room which is pretty large at 25' by 19'. This sort of scared me away from the 200s, but I'm happy.

I really wanted to try bi-amping by was told it's complicated and tough to do.

I just noticed your message - what did you end up doing? Still on the X250.5, or did you try something else? I have a pair of 800D speakers, and I was debating trying to biamp with a pair of x250.5 or x250.8 amps.

I have tested my speakers with cheaper amps, and I ABSOLUTELY preferred the sound biamped.