Tube Amp and Martin Logan Montage?

[CougarCruiser]

Someone on here might know this... I am currently in the process of selling a pair of Martin Logan Montage speakers. I have a prospective buyer who has asked if his tube amp can run these speakers?

I have no idea what tube amps are all about. How should I go about answering the question? I asked for some specs on his amp and that he could bring it over to my condo for an audition against the Sony ES receiver they are currently running on...

Thoughts? Ideas?

[Chris D]

I might be wrong, but I think it's just an issue of pure power as far as CAN the amp "run the speakers". Is the amp rated for enough wattage to drive the electrostat design of ML? They do require a lot of juice.

[Kevin P]

MLs can be used with tube or SS amps, but they recommend whatever amp you use is stable down to 2 ohms or so for best performance. This is because impedance can vary quite a bit by frequency on any electrostatic speaker. The Montage has a nominal 5 ohm impedance. I have a pair of SL3s that are 4 ohms nominal but can drop as low as 1.5 ohms. This is a challenge for all but the finest amps to drive these speakers.

If an amp puts out X watts into 8 ohms, 2X watts into 4 ohms, and 4X watts into 2 ohms, then the amp is truly stable down to 2 ohms. Few amps can do this, but stability down to 4 ohms should be adequate.

Depending on the design of the tube amp, it may prefer higher-impedance, high efficiency loads; SET type amps are like this and are usually lower power (say 8 watts). More expensive push-pull tube amps can put out more power and if the amp has a multi-tap output transformer, it likely will work well with the MLs.

Hopefully that didn't sail way over your head, but if it did, if you could post the name of the amp your buyer would want to use with your Montage, we can provide more info.

[CougarCruiser]

Ok, I feel dumb now.

That's great info -- and I have something to go on now... If I hear back from him with specs, I'll re-pose the question.

Thanks for the info and advice!

[ThomasW]

Montages aren't electrostatics, they're a MMT dynamic driver system 2-6.5" midwoofers with a planar tweeter. Any amp should drive them.

[CougarCruiser]

Ok guys, the equipment this tube guy is running is Conrad Johnson PV10 BL and the MV60SE amp. from www.conradjohnson.com, the amp is rated at 55watts.

How will that do? What does a tube amp do that an electic amp doesn't?

[Kevin P]

I didn't see a MV60SE on the website, but found the MV60 which I expect is similar. It should drive the Montage no problem, as it can be configured to drive 4, 8 or 16 ohm loads.

As for what do tube amps do that SS ones don't, well, they typically have a certain "warm" sound quality to them that some people like. That's a discussion for another thread though.

[dyazdani]

The MV60 should be fine. I've heard one driving B&W 802s, and it seemed to do well.

Last I heard MLs with tubes was a pair of Prodigys with an ARC VT100mkII. It really sounded great in the midrange, lacked a little punch, but that's to be expected somewhat, especially since a I listened with a big FPB series before I connected the ARC.