Martin Logan Summit X

[chiphoust]

With my big ARC tube amps, the speakers only get harsh at very high volumes. Otherwise they are smooth as silk and present a walk through image. The grip is not are good as solid state, but that the trade off eh? My guess is that the amps are clipping at those levels. I have tried the various vertical positions and landed at the minus one (1) degree setting as best. The toe-in was set using the flashlight technique, now iPhone flashlight technique. I am listening to the inner 1/3 of the panel at most. i am familiar with the "wall-slap" created by an improper toe-in.

Back to the point... I am thinking of auditioning the Audio Research DM450 monoblocks. ARC claims they also have a linear power supply and can deliver what ESL's need. The only concern is that these are D Class amplifiers. I tend to gravitate to Audio Research amplifiers because I love Audio Research tube pre-amps and there definitely is synergy with the combination.

Thanks for your thoughts.

IMO the current range of Martin Logans shouldn't sound hard or edgy at high volumes. If they do, it's most likely the amp's protection circuits are cutting in and are causing soft clipping. This can produce a hard and flat sound.

If so, you need an amp with higher voltage output. Remember: with ESLs it's about voltage, not current, because ESLs are capacitors, not resistors. A Devialet can supply bags of current, which makes it brilliant at driving conventional (resistive) electrodynamic speakers, but not ideal for (capacitative) ESLs.

If you have an overly bright presentation at all volumes, that's more likely to be the result of room reflections or speaker placement. Try toeing the speakers out a bit and adjusting the feet so that the panel is nearly vertical. And get lots of soft furnishings. I think MLs prefer a fairly 'dead' acoustic.

But whatever the cause of the problem, you should know immediately when you've solved it, because the speakers will sound as smooth as silk and present a 'walk-through' 3D image.

Matt