Things not working out...anyone use B&K?

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JonFo, quick question: what does the "separate them" part of this advice mean? Is it just increasing the spacing between the speakers? And how much toe in are we talking about? The flashlight adjustment in the manual says within a third of the panel. Maybe at the middle?
Thx.

It means what you deduced, to spread them apart further on the wall and angle them in a bit more so the rear wave bounces off the wall behind at an angle away from the speakers. It's not a lot, so just think of a billiard ball traveling from the back of the panel, hitting the wall and bouncing off. Would the new path clear the speaker?

This then needs to be balanced with how the front wave arrives at the listening position, which is why it's often a sequence of steps to spread the speakers apart, play with the toe-in and get to where the balance works for you.

But absorption is the cleanest way of solving this, and given your room spacing constraints, likely the only one that will solve your challenges.

BTW- all this amp swapping should be something you look at down the road. Using amp selection as a means of tone control is rather ineffective, a good preamp with a decent room corretor will get you ten times better results.
 
I found the post showing the tube traps a fellow forum member made:
http://www.martinloganowners.com/fo...he-Back-Wave&highlight=15003&d=1321129532
I'm the one who made them. If you make some as well I suggest that you stuff them (I didn't), making sure that the stuffing is secured such that it doesn't drop. Jonathan, do you remember the ones that a guy called Jon Risch used to have on his web site?

BTW, I suggest that for now you don't consider buying another receiver, but make do with whatever you have, and save your money instead for a good amplifier.

I HAVE to say this: I think Martin Logan do their customers a disservice by stating on their web site that you can use a wide range of receivers with their speakers. Receivers generally don't have the cojones to handle electrostats.
 
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@2+2,
As a fellow ML Vantage owner who had a similar problem (fatiguing highs), might I suggest a different solution? Take another look at your amplification.

While many amplifiers say they can drive a 4 ohm nominal impedance speaker, that's not quite the same as saying that they can drive MLs. As I'm sure you've know, while ML lists the Vantage as a 4 ohm speaker, the minimum impedance at 20kHz is 1 ohm. A lot of amplifiers (like the Rotel 1080) state that they can drive 4 ohm speakers, but their manufacturers don't exactly say how they perform at lower impedances. The harshness you are hearing is likely due to your amp starting to distort as impedance dips. A good test is listening to classical music (heavy on the strings) at louder-than-normal volumes. Pop music with cymbals or tambourines will work too. If the highs you hear are grating and make you reach for the remote, then I would say that your amp is being pushed into distortion. I had a pair of Emotiva UPA 1 mono blocks that were spec'd for 4 ohm speakers, but screeched like a electrocuted cat when I played anything with a lot of strings.

I switched to an old McIntosh amp (which is stable at 1 ohm), and the highs went from screechy to smooth. Have been happy with my set-up ever since.

Having said all this, I am in no way diminishing the importance of proper room treatments. They are critical to getting your speakers to play at their full potential. I'm just suggesting that the harshness problem you're facing might be caused by you amp (based on my experience).
Let your ears be the final judge!!!
 
In response to your original post, I use B&K M200 mono blocks with my Ascent i's. Yes, they have a very mellow sound and can easily handle the speakers. I had my tested a few years ago and they doubled in power down to 2 ohms.
 
@2+2,
While many amplifiers say they can drive a 4 ohm nominal impedance speaker, that's not quite the same as saying that they can drive MLs. As I'm sure you've know, while ML lists the Vantage as a 4 ohm speaker, the minimum impedance at 20kHz is 1 ohm. A lot of amplifiers (like the Rotel 1080) state that they can drive 4 ohm speakers, but their manufacturers don't exactly say how they perform at lower impedances. The harshness you are hearing is likely due to your amp starting to distort as impedance dips. A good test is listening to classical music (heavy on the strings) at louder-than-normal volumes. Pop music with cymbals or tambourines will work too. If the highs you hear are grating and make you reach for the remote, then I would say that your amp is being pushed into distortion. I had a pair of Emotiva UPA 1 mono blocks that were spec'd for 4 ohm speakers, but screeched like a electrocuted cat when I played anything with a lot of strings.

I switched to an old McIntosh amp (which is stable at 1 ohm), and the highs went from screechy to smooth. Have been happy with my set-up ever since.

Couple things . . .
I really like Rotel amps and wanted to spend under a couple grand for an amp that enjoyed working with ML's. I called Rotel, told them about my speakers, and their response was that they were "not sure" about how well their amps would perform when going close to 2ohms - let alone going below 2ohms. When compared to Krell, which states "The amplifier is stable at any load impedance", I simply had to spend a little more to get something with a lot of confidence. I love this amp.

Secondly, I can vouch for the "harshness" factor in amps that have a hard time with ML's. Billy Cobham cymbals sounded harsh until mating my speakers with my Krell.

. . . ok, a third thing . . . Another "wow" moment for me came when my journey for a great preamp ended with my current selection. Hours and hours and hours of continuous music enjoyment.
 
Dear Daniel,
The way things usually work with MLs is that you hear them fully "environmentally" optimised in a friend's home and get blown away to the extent that you feel compelled to own them (or even bigger ones if that's possible ;^)
Having acquired them, you then spend the next 6 months or a year achieving precisely "that incredible sound" by fine tuning positionally, angularly (vertical angle) and experimenting with damping (not necessarily professionally made traps). :)

One of those optimisation steps may involve inviting your local HiFi dealer to bring a selection of amplifiers to your house and to try each model for a week or 2 at a time.
MLs are pretty ruthless at revealing that 2 identically specced amps are anything but identical in their performance which is why matching is so important. Although lower and mid-range MLs are reasonably priced (by modern exhibition standards) this is actually high-end stuff you're listening to - which demands equally good ancillaries.

Thing is....your friend's home may not have had any kind of room treatments at all and yet the speakers still managed to sound spectacular ;^)
It is possible to make unmodified rooms sound great, it just needs a little persistence and experimentation to get the result you are looking for.

One method that worked for me was rotating the hifi arrangement through 90 degrees and using the window drapes behind each speaker as dampers. Behind these I have vertical blinds that provide an additional damping/diffusing layer. (I realise these are not broadband dampers but they have proved excellent.)

Don't give up too easily. The results are worth waiting for and further experimentation yields even greater reward!
Best regards,
 
Thanks everyone! I have not been posting but have been looking into the various things suggested in the replies and doing listening tests since returning after the holiday. As suggested by Bernard, I used some pillows to cover the back side of the panels to see what a tube trap behind the panels may sound like. That made a marked difference and did take much of the harshness out but I did not like the effect on the airiness and ambiance in my arrangement undermining the very reason why I wanted MLs. I also tried putting large patio furniture seat cushions behind the speakers at the wall. Not exactly acoustic panels but I thought the impact may be similar. I notice some difference but not as much as I thought. It may be because the cushions were not on the wall of the entire speaker height. Per JonFo's suggestion, I looked into the company for the custom panels and pictures and I don't see it happening...however, I may order some custom sized acoustic panels that can be positioned below the chair rails but because it would only cover the bottom half of the speaker, I am not sure if it will help all that much. I also tried using the Maven receiver as an amp and as a preamp. In amp form, it was brighter than HK, but in preamp form it was slightly more mellow than Rotel preamp.

So what is the current status? Well, I am back to Rotel preamp, HK amp using copper cables/interconnects. I want to keep the Maven for office duty considering the nominal improvement to the Vantage system. Per JonFo I increased the spacing by couple inches and increased toe in. I also acquired Music Hall DAC 15.2...that made a significant difference in mellowing out the sound...not as much as switching amps but pretty noticeable....funny because I thought my CD player was pretty good....I placed a high skinny table between the speakers with a long runner and a bunch of picutre frames that are somewhat separating the lower half of the speakers from each other. I will have to put up another picture. Now listening wise, it is borderline in terms of ear fatigue. At my normal listening levels, no fatigue. At louder volumes, I start getting fatigue. Per topofroc and ttoc, I am thinking that a better amp may be the best option considering that any room treatments would be pretty minimal. The wife does not want any more "clutter" in the living room..a position I understand.

As mentioned, the HK amp is only 80watts although I am only using 2 of the 5 channels. Jimbill mentioned using B&k monoblocks which appear to have been top of their line. Krell and McIntosh was mentioned as well. All of those are likely out of my price range but I will snoop around. B&k ST-140 got really good reviews from Sam Telling at Stereophile powering Quad ESL. I am thinking that it may be worth trying out although I would look for something with a bit more power and newer. Victor's suggestion of trying out different amps from a dealer would be nice except that I don't think I can afford anything new....so I will look at acquiring another amp in the 100-200watt/ch range that is described as being "warm, laid back" while avoiding amps described as "detailed."
I will loop back here as to what else I try and the outcome.
 
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