I also use the Behringer crossover. I drive it digitally with the Wiim Mini Pro streamer. Much lower noise than the analog input and only one D/A conversion needed.
Attachments
Lots of temporary sticky stuff going on - and I see I put it on the same side as the main exciter, not the diagonally opposite side
Eucy,
Yep, I did try this last year when I was doing a series of outdoor measurements. On my panel, I did get the best result with the exciter at the "opposite corner", rather than the close corner, but I suspect it depends on the panel and exactly what feature of the response you are looking at.
Eric
If I do experiment with separate plates or exciters for treble, I will probably go with simple 1st order passive filters. With DML I'm not that worried about a lot of overlap between the exciters, so can use a very simple filter basically just to take a bit of load of the treble exciter.
In my case a 3-way active setup would add too much complexity. It is a lot of cables, and since I do quad surround that would mean a lot of DSP channels, and my 8 outs would not be enough.
And it does seem to make sense to design the combination as one unit tweaked into balance on a hardware level before applying EQ to tune it.
In my case a 3-way active setup would add too much complexity. It is a lot of cables, and since I do quad surround that would mean a lot of DSP channels, and my 8 outs would not be enough.
And it does seem to make sense to design the combination as one unit tweaked into balance on a hardware level before applying EQ to tune it.
Eucy
Sorry, I didn’t mean to imply that. I would say it actually worked pretty good.
Curiously, the best thing it did was to smooth out a hump in the middle of frequencies which I hadn’t expected. But the highs were still a little weaker than I was hoping for.
Eric
Sorry, I didn’t mean to imply that. I would say it actually worked pretty good.
Curiously, the best thing it did was to smooth out a hump in the middle of frequencies which I hadn’t expected. But the highs were still a little weaker than I was hoping for.
Eric
Eucy
Sorry, I didn’t mean to imply that. I would say it actually worked pretty good.
Curiously, the best thing it did was to smooth out a hump in the middle frequencies which I hadn’t expected. But the highs were still a little weaker than I was hoping
Eric
Sorry, I didn’t mean to imply that. I would say it actually worked pretty good.
Curiously, the best thing it did was to smooth out a hump in the middle frequencies which I hadn’t expected. But the highs were still a little weaker than I was hoping
Eric
Here's a new interesting dml build with exciters doing lows and highs on a single panel, using two amps and DSP.
Now considered a multi-way panel/speaker.
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Hello
Just to come back on a previous Steve's post about the benefit of a foam strip in a small hole at the center of the ring area.
I posted the measurements below on the PETTaLS thread (#340] where the discussion is around the HF resonances and their possible causes.
This is a 9mm Depron panel without any skin treatment.
Without damping, there is a huge peak at 12k. With the damping, the IR (green) is much cleaner.
Christian
Hello Christian.
Hip Hip Hooray 🥳.
At least someone is listening to me 😃
Looking at the response of the depron material, maybe you need to reduce the thickness of the foam insert a little more.
Are you using the softened foam sponge material we talked about ?
I have not used this depron material myself, but you need to reduce the major peak without causing dips and peaks in the response in other areas.
I usually use several different thicknesses of foam until I get the desired response.
Too much and the area is over damped , and can cause problems.
Too little and foam will only lower the peak a little.
I would probably err on the side of too little rather than too much.
I'm glad to have been of help.
Steve.
Hip Hip Hooray 🥳.
At least someone is listening to me 😃
Looking at the response of the depron material, maybe you need to reduce the thickness of the foam insert a little more.
Are you using the softened foam sponge material we talked about ?
I have not used this depron material myself, but you need to reduce the major peak without causing dips and peaks in the response in other areas.
I usually use several different thicknesses of foam until I get the desired response.
Too much and the area is over damped , and can cause problems.
Too little and foam will only lower the peak a little.
I would probably err on the side of too little rather than too much.
I'm glad to have been of help.
Steve.
Here are some additional measurements about the central area.
To make it short, I have had better results today with a small piece of EPDM cut in a D shape weather strip than with the yesterday yellow sponge. Magic sponge was not as good.
Then I thinned the area in a shape which is suppose to be the tip of a parabola (see the tool below: a piece of wood topped by something replacing now the sand paper at the end of a dremel). Alone, it is not as good as the hole + sponge tested yesterday, with a piece of EPDM it is better (see below)
Red is the hole + sponge (yesterday post)
Blue is the thinned area + EPDM. The IR is very nice... I am wondering now what happens just before 1ms... I already observed that. An hypothesis is diffraction or let say emissions from the edges.
All of that don't say if it really matter and important for the listening pleasure. Anyway, any cheap adjustment that makes the IR/FR nicer is interesting.
Christian
The tool:
To make it short, I have had better results today with a small piece of EPDM cut in a D shape weather strip than with the yesterday yellow sponge. Magic sponge was not as good.
Then I thinned the area in a shape which is suppose to be the tip of a parabola (see the tool below: a piece of wood topped by something replacing now the sand paper at the end of a dremel). Alone, it is not as good as the hole + sponge tested yesterday, with a piece of EPDM it is better (see below)
Red is the hole + sponge (yesterday post)
Blue is the thinned area + EPDM. The IR is very nice... I am wondering now what happens just before 1ms... I already observed that. An hypothesis is diffraction or let say emissions from the edges.
All of that don't say if it really matter and important for the listening pleasure. Anyway, any cheap adjustment that makes the IR/FR nicer is interesting.
Christian
The tool:
@Pepe
If it’s easy to check it out?
I remember very well (? It’s 50 years ago!) a good and spatial fullrange sound produced by those speakers at that Hifi show. But I don’t know how styrofoam is altering in 50 years.
Christian... Do you think this is an EPS/XPS issue only... What about ply or other thin materials??
Frankly I don't know. I have a measurement of a 2mm plywood without peaks. I haven't search in all my tests for other materials but I think some other show it also. I remember a test of a 1.2mm acrylic (a bit thin) for which I search for a countermeasure for this peak. So I am in the idea it might be more a question of stiffness and mass of the material. It would be interesting to search for the modes of a clamped or free edge disc to see if it gives something plausible.