Clio09
The subs are Dynaudio Acoustics BM12s . In the search to replace the previous sub they were a kind of dark horse for me. Not really known in the consumer area in North America, but well known and used in the recordings studios. For serious listening it’s just me really, so my setup with two works really well with me sitting in the area of the couch position. If I was to extend the seating "around" the room, and needed good sound all around the room, one could just add one or two more in master slave fashion. Each sub has its own 250 Watt Class a/b amplifier. I was given the ability to trial them first.
The subwoofer category in the audiophile world has to be at the top when it comes to # of choices these days ? So many choices. I find the companies like to call the way they control their woofer by a special code name. Dynaudio’s special woofer control is called CEC (Cone Excursion Control) :^)
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Your comments re; RM3 settings on the OTL versus Push Pull amp were very interesting - thanks for that.
There is no significant difference in the RM-3 settings with either the amps. Sometimes I trim the high end a couple dB when running the RM-10 depending on the music. I run the M-60s with 4 tubes each channel so probably about 20 watts. I do use Speltz autoformers with them at 3x setting so that bumps up their power at some frequencies.
My Quad room has an adjacent music room which is really my main room - defined by (where do I go if I need a quick fix) Fwiw the Quad room can not be called my main room because the right sub is placed in very close proximity to where my wife sits upstairs ......anyway.
So I was running 200 wpc OTL’s on the matrix 800 in that room. It was sweet and very nice. Then one day when they were being serviced, I subbed in my modded RM9. It outperformed the OTL’s in the bass department with half the power. That was sort of the beginning of the end for them.
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sorry to digress back to the Quad 57.
The three wood legs allow the speaker to be planted well. This is important. When raised it is important to affix them in a way to allow for the same thing to happen. Stock presentation is like viewing an orchestra from a balcony. I have spent time in the balconies, but it is more the norm to be in a room with multiple tables, and the band/group of musicians on an elevated stage. So the first mod was a 2x4 piece of wood under the rear leg - lowering - the projection angle of the speaker - but - raising - the soundstage. This is one example for me of "Audio Magic" happening in this Audio Hobby. When you experience this the first time, it goes against the way we think. IMO, we don’t generally think about the back wave on an ESL.
From there the speakers were raised onto Arcici stands and moved 7 feet out into the room. This provided the best bass in the space, but I needed better sound dispersion. Raising another foot did it. If you click on the runner and see pic 41 - the last one shows current setup from the last year. The subs are positioned with the woofer cone slightly forward of the speakers with 0 Phase.