The recordings are really good. Too bad that I don't have a stud wall.
But, all my brick walls are fixed with gypsum boards from the inside. Must try this idea.
Chdsl So you have gyprock glued directly onto a brick and mortar wall and you want to try an exciter on the gyprock? Is that what you're saying?
If that's the case, I don't think it's going to work well. For LDLs to work, the panel has to be able to flex and vibrate. On a stud wall, gyprock can work because it's only anchored at the studs but the panel can flex and vibrate in between and it can produce some volume because you've essentially got a cavity behind the gyprock and between the studs. If your gyprock is glued to a very rigid brick wall, it will be constrained from vibrating and flexing everywhere (not just on the studs 16" or whatever your local building standard is apart).
What you'll be doing is creating something very similar to when they do seismic for oil exploration using a vibro-seis unit which is essentially a huge exciter on wheels. The energy from the exciter will travel through the gyprock and when it hits the interface with the brick a portion of it will reflect back and the rest will refract and continue propagating further into the brick wall. That energy will continue going through the brick wall until it hits another density interface and the same thing will happen again; some will reflect back and the rest of the energy will refract and continue on into the next medium. The bottom line is, most of the vibrational energy may be lost into the brick wall and whatever is behind it and what energy that does stay or come back to the drywall, will not be able to create much sound because the drywall layer is so heavily damped and constrained because it's glued onto a brick wall which is not going to vibrate/flex much from the little bit of energy your exciter will impart. THe vibrations in the gyprock will have almost no amplitude. Based on this reasoning, my guess is that putting an exciter on a wall constructed in that way will yield very satisfying results but what the hell, I've been known to be wrong before so give it a try and see what happens.
If that's the case, I don't think it's going to work well. For LDLs to work, the panel has to be able to flex and vibrate. On a stud wall, gyprock can work because it's only anchored at the studs but the panel can flex and vibrate in between and it can produce some volume because you've essentially got a cavity behind the gyprock and between the studs. If your gyprock is glued to a very rigid brick wall, it will be constrained from vibrating and flexing everywhere (not just on the studs 16" or whatever your local building standard is apart).
What you'll be doing is creating something very similar to when they do seismic for oil exploration using a vibro-seis unit which is essentially a huge exciter on wheels. The energy from the exciter will travel through the gyprock and when it hits the interface with the brick a portion of it will reflect back and the rest will refract and continue propagating further into the brick wall. That energy will continue going through the brick wall until it hits another density interface and the same thing will happen again; some will reflect back and the rest of the energy will refract and continue on into the next medium. The bottom line is, most of the vibrational energy may be lost into the brick wall and whatever is behind it and what energy that does stay or come back to the drywall, will not be able to create much sound because the drywall layer is so heavily damped and constrained because it's glued onto a brick wall which is not going to vibrate/flex much from the little bit of energy your exciter will impart. THe vibrations in the gyprock will have almost no amplitude. Based on this reasoning, my guess is that putting an exciter on a wall constructed in that way will yield very satisfying results but what the hell, I've been known to be wrong before so give it a try and see what happens.
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Recordings.
The recording app is the freebie version,so pauses after 3minutes.
But I have noticed that it sounds a bit odd after the pause!
I think it goes into mono after it pauses ,for some reason?
Something sounds odd anyway?
Which to me ,gives the sound a more unnatural muffled room echoe sound?
Just thought I'd mention this in case you are thinking the same?
Steve.
The recording app is the freebie version,so pauses after 3minutes.
But I have noticed that it sounds a bit odd after the pause!
I think it goes into mono after it pauses ,for some reason?
Something sounds odd anyway?
Which to me ,gives the sound a more unnatural muffled room echoe sound?
Just thought I'd mention this in case you are thinking the same?
Steve.
Stud work panels thoughts.
Obviously a more substantial exciter is needed,I have seen a shaker that goes up to 15k ,this I think might be a better option?
Please don't buy the hdn8 as this is a flawed exciter and badly put together.
The plastic casing produces far too much noise and produces very nasty noises when you start turning the volume up to anything useful.
I was thinking that if I was to make a similar type of panel as my rigid dml panel,I would have to have (probably)a central beam spreading the sound across the panel,would it be straight down the centre or running from corner to corner?
Or would the beam be better going across the shorter central width?
Maybe a thicker 5mm ply or plaster board ?
I'd be basically changing my panel into a fake stud wall?
Or if using a thicker panel ,would it be better to attach the exciter directly to the rear of the panel?
I may try and attach the hdn8 to the rear beam when I get time, and see how this sounds,but I'm not expecting much .
But that's about as far as I want to go with this,as good as it sound,I'm more interested in smaller lighter materials.
Sorry for rambling 😊
Steve
Obviously a more substantial exciter is needed,I have seen a shaker that goes up to 15k ,this I think might be a better option?
Please don't buy the hdn8 as this is a flawed exciter and badly put together.
The plastic casing produces far too much noise and produces very nasty noises when you start turning the volume up to anything useful.
I was thinking that if I was to make a similar type of panel as my rigid dml panel,I would have to have (probably)a central beam spreading the sound across the panel,would it be straight down the centre or running from corner to corner?
Or would the beam be better going across the shorter central width?
Maybe a thicker 5mm ply or plaster board ?
I'd be basically changing my panel into a fake stud wall?
Or if using a thicker panel ,would it be better to attach the exciter directly to the rear of the panel?
I may try and attach the hdn8 to the rear beam when I get time, and see how this sounds,but I'm not expecting much .
But that's about as far as I want to go with this,as good as it sound,I'm more interested in smaller lighter materials.
Sorry for rambling 😊
Steve
Last night i bought a 4'x8' x .75" sheet of green foam. Cut it in half brought it outside and it was so windy it was trying to knock me over and they just broke into pieces and then flew across the parking lot and i had to go around and pick them up. Should still able to make at least 2 panels.
I want to paint a chladini pattern on my panels gold/black. Thinking about mounting a daex25fhe-4 to the front side, might look cool. If it would help the low end i could add add 3oz (85g) lead fishing weight to the exciter. Run a piece of fishing line from top of panel before gluing it if voice coil sag was an issue.
I want to paint a chladini pattern on my panels gold/black. Thinking about mounting a daex25fhe-4 to the front side, might look cool. If it would help the low end i could add add 3oz (85g) lead fishing weight to the exciter. Run a piece of fishing line from top of panel before gluing it if voice coil sag was an issue.
