Audio Research and Martin Logan Montis

Zd542

This is the kind of non linear frequency response that may happen with a tube amp at 4.5khz with the Montis, -2db!!! because of it's -55 degree phase shift and combined 3ohms load, because the amp can't deliver current.
It has nothing to do with wattage! It's all about current. Not very flat is it?

http://www.stereophile.com/images/archivesart/A88FIG01.jpg

Cheers George

What difference does it make if the system sounds OK?

What about a different speaker like the Prodigy? Would you say the same about that one?

03-06-15: Zd542
What difference does it make if the system sounds OK?

What about a different speaker like the Prodigy? Would you say the same about that one?

Well your not listening to a flat frequency response, it like having a fix tone control embedded, + - 4db from 20hz to 20khz

As for the Prodigy, it too has an evil load, of -55 degrees with 3ohms, but it's further up around 7khz.

http://www.stereophile.com/content/martinlogan-prodigy-loudspeaker-measurements

As for Bfin3 Spire's there is no load v phase angle graph done on these, so who knows.

Cheers George

"What difference does it make if the system sounds OK?"

A technical mismatch does not mean the results will not "sound good". Its a red flag indicating performance as intended may not be optimal. But nothing says optimal "performance" means best sounding to all. Optimal performance on paper is always a good omen though. The sound can always be tweaked to tastes to some extent once one has optimal performance but if not its possible that no tweaks might suffice.

Its more about the selection process and how to be in the best possible position to achieve satisfactory results more so than a question of what might sound good or best to any particular individual.

"03-06-15: Georgelofi

03-06-15: Zd542
What difference does it make if the system sounds OK?

What about a different speaker like the Prodigy? Would you say the same about that one?

Well your not listening to a flat frequency response, it like having a fix tone control embedded, + - 4db from 20hz to 20khz"

In order to have a situation like that, some pretty big assumptions have to be made. All the other components in the system, including the room will have to be neutral and deliver a frequency response that is flat, in order for that one issue listed above to manifest itself as a specific problem. By the time you're done picking matching components and setting them up in any given room, another component could balance the imperfection in the FR out, or even make it worse. None of this happens in a vacuum. Its a challenge getting all the components in a system, set up and working well, given they're flaws as well. Not to mention, planer speakers, in general, don't measure well to begin with. They never have and its something you really have to accept when you buy them.

The reason I asked about the Prodigy was was that, when it first came out, I was invited by my dealer to attend the new product seminar that ML gives when a major product is released. I'm not sure if they do this for all dealers, but the one I used to go to was very big and did a lot of volume. At the seminar, they selected some components in the store to do the setup, and the ML rep. (Gayle Sanders), picked an ARC VT-100 to power them with. He could have chosen anything. The store had no shortage of big, powerful solid state amps. And the Prodigy looks to be a much more difficult load than the Montis that we're talking about here. So, if an amp like that is OK for the guy who designed the speakers, I'm OK with just leaving it at that. But that's my own personal decision, and I won't try force it on anyone else. To be fair, I've heard ML sound great with Krell, Threshold/Pass, Counterpoint, McCormack and ARC solid state amps. There's no shortage of good choices regardless of personal preference.