For the last few years I've been thinking about getting a new center speaker because I figured it would easily be bested by any new speaker that might even cost less than what the Motif cost new. I've been thinking that the Motif hasn't been sounding as good, but it's been good enough to get enjoyment from watching movies. So I've been gearing up for an early 2023 purchase of a Focus, most likely. My room isn't large enough for an Illusion.
Last week I began doing some measurements as simply a test of some Isoacoustics ISO Pucks I had laying around that were for a subwoofer I had a few years back. I hadn't used the pucks since as I wasn't convinced they did much, at least not for subs. So I started experimenting with the Motif on 3 of the pucks with granite slabs for added so the weight was within the spec the pucks are rated for. So I'm going through with things and I began tailoring how the testing is being done for repeatability etc, then began to see that the Motif has some odd frequency response curves. Normally I use Dirac for all the HT stuff, so never really noticed these odd things being as pronounced as now.
The electrostatic panel seems to have lower output than I remembered it to have. Lower than where it meets the woofers at 450Hz, and lower than where it meets the tweeter at 4000Hz. Plus it seemed a bit ragged. Dirac always fixes this stuff, and for HT it seemed ok, so I never thought about it more than that.
Also, the woofers exhibit a big "bump" between 100-200Hz, and I've seen this since I started using REW a little less than 3 years ago. I just figured it's a design flaw. Anyway, with the tests I did last week this bump was different than a few years ago and dropped off above 100Hz quite sharply, so this is new, not good.
How to fix this?
I vacuumed the stat panel, but more intensely and for much longer than usual. Still no good. I cut some thin, stiff, cardboard to use for a custom vacuum cleaner nozzle extender. This is to attempt to get the vacuum nozzle into the very tight spaces on the back of the stat panel, which is otherwise impossible. I then was extremely diligent about getting that vacuum nozzle everywhere possible in back, and on the front, and vacuumed a long time. I think this helped a tiny bit with panel output, but problems remained.
So I opened up the back to look at the capacitors and check them. They looked ok. Took out my ESR meter and they all checked out REALLY GOOD, I mean really low ESR. Next I re-seated every wire connection by pulling it and pushing it back onto its connector. Then I tightened all the screws on the wiring terminal strip, and about half the screws were not tight. Then I noticed the back panel was a little warped between each screw location, so I suspected that the back might not be sealing well and is maybe affecting the woofer output. So I added some thick pliable tape to the perimeter of the routed recess the back panel inserts into and sealed it back up.
Prior to opening up the speaker cabinet I measured each stat "strip" with a mic less than 1/4" away, and did the same for the woofers. I then did the same after the fixes and found improvement. The stat strips each seemed better. The woofers looked about the same as before, but I think this is because there's nothing wrong with the drivers, and with the mic that close the mic is really only hearing just the driver and not much of the box.
The first acid test with the mic at the MLP which showed good improvement in both the panel (mids) and the woofers (bass). So I mounted it back on the wall and began comparing pre and post fix. Now the bass is much better, and the frequency response from the panel is smoother, and like I said before just a bit more output. No single part of the fixing is responsible, but everything together made this a very good outcome.
As I'm writing this I'm listening to music through only the Motif. Due to that big bump I have the speaker setup as Small and the crossover setting at 140Hz to tame the bass, otherwise it just sounds like too much bass bloat. No subwoofer, just the Motif. Surprisingly the bass still extends below 100Hz at a level that's higher than the stat panel just above its crossover of 450Hz. That'll tell 'ya how much bass is boosted between 100-200Hz on this speaker.
So the speaker sounds very good. I'm still going for a demo of the Focus tomorrow, but the Motif is doing ok for now.
edit: I just realized one subwoofer is operating. I forgot the one in the rear that's wireless. I unplugged everything else.So my statments above about the extended low bass are not correct when I was listening to music while the Motif was setup as Small. For all the tests it was setup as Large so there was no possibility of subwoofery. edit2: I was half smart, the miniDSP that controls the subwoofers for BM and LFE had BM turned off, so it's only LFE being passed through.
I realized my mistake when I began watching a movie and heard lots of really low bass sound effects, LFE.So when I setup the speaker as Small, that subwoofer kicked in. Only LFE was operating, no Bass Management.
Last week I began doing some measurements as simply a test of some Isoacoustics ISO Pucks I had laying around that were for a subwoofer I had a few years back. I hadn't used the pucks since as I wasn't convinced they did much, at least not for subs. So I started experimenting with the Motif on 3 of the pucks with granite slabs for added so the weight was within the spec the pucks are rated for. So I'm going through with things and I began tailoring how the testing is being done for repeatability etc, then began to see that the Motif has some odd frequency response curves. Normally I use Dirac for all the HT stuff, so never really noticed these odd things being as pronounced as now.
The electrostatic panel seems to have lower output than I remembered it to have. Lower than where it meets the woofers at 450Hz, and lower than where it meets the tweeter at 4000Hz. Plus it seemed a bit ragged. Dirac always fixes this stuff, and for HT it seemed ok, so I never thought about it more than that.
Also, the woofers exhibit a big "bump" between 100-200Hz, and I've seen this since I started using REW a little less than 3 years ago. I just figured it's a design flaw. Anyway, with the tests I did last week this bump was different than a few years ago and dropped off above 100Hz quite sharply, so this is new, not good.
How to fix this?
I vacuumed the stat panel, but more intensely and for much longer than usual. Still no good. I cut some thin, stiff, cardboard to use for a custom vacuum cleaner nozzle extender. This is to attempt to get the vacuum nozzle into the very tight spaces on the back of the stat panel, which is otherwise impossible. I then was extremely diligent about getting that vacuum nozzle everywhere possible in back, and on the front, and vacuumed a long time. I think this helped a tiny bit with panel output, but problems remained.
So I opened up the back to look at the capacitors and check them. They looked ok. Took out my ESR meter and they all checked out REALLY GOOD, I mean really low ESR. Next I re-seated every wire connection by pulling it and pushing it back onto its connector. Then I tightened all the screws on the wiring terminal strip, and about half the screws were not tight. Then I noticed the back panel was a little warped between each screw location, so I suspected that the back might not be sealing well and is maybe affecting the woofer output. So I added some thick pliable tape to the perimeter of the routed recess the back panel inserts into and sealed it back up.
Prior to opening up the speaker cabinet I measured each stat "strip" with a mic less than 1/4" away, and did the same for the woofers. I then did the same after the fixes and found improvement. The stat strips each seemed better. The woofers looked about the same as before, but I think this is because there's nothing wrong with the drivers, and with the mic that close the mic is really only hearing just the driver and not much of the box.
The first acid test with the mic at the MLP which showed good improvement in both the panel (mids) and the woofers (bass). So I mounted it back on the wall and began comparing pre and post fix. Now the bass is much better, and the frequency response from the panel is smoother, and like I said before just a bit more output. No single part of the fixing is responsible, but everything together made this a very good outcome.
As I'm writing this I'm listening to music through only the Motif. Due to that big bump I have the speaker setup as Small and the crossover setting at 140Hz to tame the bass, otherwise it just sounds like too much bass bloat. No subwoofer, just the Motif. Surprisingly the bass still extends below 100Hz at a level that's higher than the stat panel just above its crossover of 450Hz. That'll tell 'ya how much bass is boosted between 100-200Hz on this speaker.
So the speaker sounds very good. I'm still going for a demo of the Focus tomorrow, but the Motif is doing ok for now.
edit: I just realized one subwoofer is operating. I forgot the one in the rear that's wireless. I unplugged everything else.
I realized my mistake when I began watching a movie and heard lots of really low bass sound effects, LFE.
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