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Practical meaning other than something like "get XYZ because those are crap". ;-) I always wanted a pair of ESS AMT 1A's as the Heil AMT sounds wonderful and detailed. Now that I have a pair I understand why people always said the lowend was lacking. Now these things have a 12" woofer with a ditto sized passive radiator mounted directly behind the woofer. They are mounted approximately 2 feet up from the bottom and the cabinet volume is *very* roughly about 2'x2'x3' = 12 cubic feet. The cabinet is pretty packed with acoustic dampening material. You'd think that they would put out some bass but in fact they are quite subdued. Im wondering is the subdued bass resulting from the drivers being so high up or could it be overpacked with dampening material? Of course it could always be the woofer is crap too - but I don't think so. Or maybe the passive is simply providing an out-of-phase wave that is partially cancelling the front (eg crappy cabinet design). Anyone else had these or know of any sources for detailed info on the drivers and cabinet design? Thanks!
Maybe no help but have you tried putting the speakers in room corners?
Are the speakers bone stock. Could someone have modified them at all? Maybe wired the crossover out of phase inside the cabinet? Those are pretty old now maybe a crossover rebuild is in order. You did not say what you were driving them with. When you say you always wanted a pair and describe the sound; does that mean you are familiar with them and these particular examples are showing this problem? I have heard them many times due to a friend who owned a pair and he eliminated the passive radiator by blocking up the hole with plywood; he liked them better that way. J.R.
Thanks for the replies folks. You know I pulled out one of the woofers and it does appear that someone has been playing around in there so I decided that it is necessary to follow the wiring and see what comes up. A 12" woofer should make more oomph than it does. First thing I noticed was that the woofer appears to be wired with 18 ga wire. That seems a bit skimpy to me with a several hundred watt rating. I always went with the gauge that actually goes from the speaker lugs to the coil - which looks to be about 14-16 ga. So now I'm gonna take 'em all apart, get 'em reconed while I'm rewiring. What I would really like to know is how much acoustic stuffing is supposed to be in the cabinets. The stuff was literally touching the back of the woofer and that ain't right. If there is too much then the woofer would be overdamped which can also cause problems. So I guess I'm now in experimentation mode unless someone who has detailed knowledge of these speakers speaks up here. Thanks for the comments - the phase comment prompted me to open them up to look for problems. BubbaJon
Yes the speakers are stock. Pretty hard to miss that massive cast aluminum frame. I'm driving them with 80 watts. Yes I have heard these before. The Heil AMT's are as sweet as I remember but the bass is definately lacking. I think you are on to something with your modified statement though - read the next mesage reply... Thanks, BubbaJon
I have owned a pair of amt monitors for 24 years and have just recently had the 12 inch bass and 12 inch passives serviced because of rot. I cetainly cant say mine have ever been short of base..My model has the passive beneath the bass driver..I am looking where to buy a spare of diaphrams in case the original fail..ESS just ignore my requests for info and they never answer the phone steve Wellington New Zealand