Leob.
I guess, my point is that there could be more than one problem with your exciters.
Also , you mentioned over heating , which can be a major issue with eps or xps.
The heat can easily melt these panels, I know this from experience.
The problem is having to check each exciter individually to see if you can see any movement of the glued parts, this is not always obvious.
Luckily I only have one per panel to worry about.
It usually ends up with me prodding the exciter with a tooth pick in various places to see if it altars the noises in any way or holding the magnet end and moving it from side to side to see if the noises stop ?
Debris could have also got into the coil gap.
I have a few that I haven't been able to fix , which I have now written, bad coil, on them to make sure I don't use them again ! 🙄
Over powering and exciter wobble or sag are the major killers of exciters, plus quality control in production.
The holes in the back of my exciters are purely for coil cooling, they do not have threads, so I never block these holes .
I have shown methods for easily and precisely mounting exciters without blocking air vents.
Also when I tried to use 2 exciters near each other on the same panel ,as in my video, I noticed they were not working together properly, but fighting each other.
So, actually, How much louder does a panel really go with four exciters, than a panel using only one ?
I don't see a way of keeping more than one exciter in phase with the panel at the same time ?
At some points through the frequency range, they will be at odds with each other , causing all sorts of problems.
Except if you have 2 exciters in push pull mode, of course, but this still has its problems , but at least they are working together.
Sorry this post has got too long.
Steve.
I guess, my point is that there could be more than one problem with your exciters.
Also , you mentioned over heating , which can be a major issue with eps or xps.
The heat can easily melt these panels, I know this from experience.
The problem is having to check each exciter individually to see if you can see any movement of the glued parts, this is not always obvious.
Luckily I only have one per panel to worry about.
It usually ends up with me prodding the exciter with a tooth pick in various places to see if it altars the noises in any way or holding the magnet end and moving it from side to side to see if the noises stop ?
Debris could have also got into the coil gap.
I have a few that I haven't been able to fix , which I have now written, bad coil, on them to make sure I don't use them again ! 🙄
Over powering and exciter wobble or sag are the major killers of exciters, plus quality control in production.
The holes in the back of my exciters are purely for coil cooling, they do not have threads, so I never block these holes .
I have shown methods for easily and precisely mounting exciters without blocking air vents.
Also when I tried to use 2 exciters near each other on the same panel ,as in my video, I noticed they were not working together properly, but fighting each other.
So, actually, How much louder does a panel really go with four exciters, than a panel using only one ?
I don't see a way of keeping more than one exciter in phase with the panel at the same time ?
At some points through the frequency range, they will be at odds with each other , causing all sorts of problems.
Except if you have 2 exciters in push pull mode, of course, but this still has its problems , but at least they are working together.
Sorry this post has got too long.
Steve.
I guess that would be ideal, although it seems like at least initially supporting them from the back with a screw in the hole in the back did make them balanced enough to avoid distortion. But at the first event I did they played for a couple of days a string suspension that was not precise and sufficient to hold them completely level. And that seems to have caused distortion that can no longer be helped by neither supporting them or placing plates horizontal.
According to soundimports where I bought the exciters:
Code:
The screwhole on the Dayton Exciters is for production purposes and not meant for mounting. A free hanging exciter is a perfect viable construction. The sagged suspesion is probably caused by aging over time and use. Xcite invested a lot of time in optimizing the suspension (spider) and will probably have less aging.Thanks Eric,
I'm using DAEX30HESF-4
https://www.diyaudio.com/community/threads/dml-pa-systems.390363/page-8#post-7309172
https://www.diyaudio.com/community/threads/dml-pa-systems.390363/page-8#post-7309172
Will have to take som pictures of my latest design as well...
All good tips, but since I have 64 exciters that so far of the 8 I tested now all have the problem, I guess that makes it unlikely with for example debris or bad gluing.
The DAEX30HESF-4 has a hole in the middle back with M6 thread.
I don't have any comparable measurements with one exciter getting the same wattage as 4 on the same plate. Since my plates have not been entirely consistent and the EPS is destroyed when changing exciters, it is not so easy to do that kind of comparison. But using a cluster of four exciters seems to work really well, and is tried and tested design by Tectonic for their PA speakers. They will then basically act as one very large exciter with a big center, and it seems like it helps with giving pronounced transient information for example. And sensitivity is very good.
Remember that sound travels very fast in EPS, so a few cm large area between the exciters will not result in cancellations in a range that is relevant really.
Of course, more elements will increase sensitivity but usually that means each element has its own cone. When instead sharing a plate, I see the logic in some cancellation happening, although I doubt it would happen in a band where it is audible. But more exciters adds mass to the plate, which should decrease sensitivity to some degree. But even then the end result is more sensitivity since each element should add 3dB even if the power remains the same.
When you both double the power and number of elements, you should get a 6dB increase. I cannot swear that I get the full +18dB compared to a single exciter, but I'm sure it is very close. So for a PA application there is no choice really. A single exciter plate will just not have a chance to keep up with any half decent sub. I need something like 2 plates with 4 exciters to keep up with one sub typically., which means a total of 16 plates for my setup. My guess is that by splitting it up to 64 plates with a single exciter I would hardly see a 1 dB improvement.
Hello all,
some of the above posts now make me wonder if there is actually a 'Life span' of exciters.
Apart from over-loading & heating, I wonder if some brands and models are most resilient (?)
Because they are a 'relatively new' product, there is probably no real information regarding this.
From a simple visual inspection of the Dayton EX32's I'm about to use, the suspension system
appears to be made of Spring Steel, so I doubt it would sag or fail > without heat.
This makes me mention that there are a lot of low-power exciters out there and people must
take this into consideration when building. So many amplifiers today have a lot of power.
This is why I will be using twin exciters (80W RMS) and also filtering-out very low bass frequencies.
CHEERS
some of the above posts now make me wonder if there is actually a 'Life span' of exciters.
Apart from over-loading & heating, I wonder if some brands and models are most resilient (?)
Because they are a 'relatively new' product, there is probably no real information regarding this.
From a simple visual inspection of the Dayton EX32's I'm about to use, the suspension system
appears to be made of Spring Steel, so I doubt it would sag or fail > without heat.
This makes me mention that there are a lot of low-power exciters out there and people must
take this into consideration when building. So many amplifiers today have a lot of power.
This is why I will be using twin exciters (80W RMS) and also filtering-out very low bass frequencies.
CHEERS
I'm not the only one that has reported issues with sagging, so it seems to be a common issue at least with the larger heavier exciters.
So I am a bit surprised that instructions from both the seller and Dayton says that they do not require any suspension, and that they are in fact intended to support themselves.
I first noticed the sagging issue on one test plate with brand new exciters when they where on a hot veranda in direct sunlight, and they had not been playing anywhere near rated power, so it seems like you don't even need to push them hard, it is enough that the ambient temperature becomes high enough.
I think many of my exciters will been exposed to direct sunlight, perhaps that been enough to make them sag?
Has anyone been using larger exciters without suspension for an extended period without issues? With what environmental conditions, and have you pushed them hard for extended durations?
So I am a bit surprised that instructions from both the seller and Dayton says that they do not require any suspension, and that they are in fact intended to support themselves.
I first noticed the sagging issue on one test plate with brand new exciters when they where on a hot veranda in direct sunlight, and they had not been playing anywhere near rated power, so it seems like you don't even need to push them hard, it is enough that the ambient temperature becomes high enough.
I think many of my exciters will been exposed to direct sunlight, perhaps that been enough to make them sag?
Has anyone been using larger exciters without suspension for an extended period without issues? With what environmental conditions, and have you pushed them hard for extended durations?
Hi Leob
Have you considered what exactly is moving to cause the sag?
It would seem highly unlikely that the coil would sag under its own mass alone, therefore there must be a load on the coil caused either by the downward sag of the panel itself relative to your mounting, or flex in your mounting, which by the position of the mount, would induce a couple, or moment, thereby displacing the coils.
Given the low mass of the foam panel, I suspect that twisting/flex in the mounting is the culprit.
Obviously, with a perfectly rigid brace securely screwed to the rear of the exciters, and a panel which doesn't shift downwards over time, there should be no shear or torque on the coils to cause distortion.
Eucy
Have you considered what exactly is moving to cause the sag?
It would seem highly unlikely that the coil would sag under its own mass alone, therefore there must be a load on the coil caused either by the downward sag of the panel itself relative to your mounting, or flex in your mounting, which by the position of the mount, would induce a couple, or moment, thereby displacing the coils.
Given the low mass of the foam panel, I suspect that twisting/flex in the mounting is the culprit.
Obviously, with a perfectly rigid brace securely screwed to the rear of the exciters, and a panel which doesn't shift downwards over time, there should be no shear or torque on the coils to cause distortion.
Eucy
As I mentioned, when I first observed it, exciters was not suspended at all. It was before the first event I noticed distortion on a test plate that was on a sunlit veranda.
I do think the problem should not have occurred if I had suspended them to begin with, but it was clear already after testing them on the veranda that there was some permanent damage from running them unsuspended since they still needed suspension also after cooling down. Probably time, more sunlight, and perhaps plates moving slightly like you suggest, have made the symptoms worse and worse.
I do think the problem should not have occurred if I had suspended them to begin with, but it was clear already after testing them on the veranda that there was some permanent damage from running them unsuspended since they still needed suspension also after cooling down. Probably time, more sunlight, and perhaps plates moving slightly like you suggest, have made the symptoms worse and worse.
I fought for a long time with the weight of the magnets that took the speaker piston out of axis, it can only be resolved with a very rigid support on which to screw the speaker from behind, as far as breakages in my case are always one speaker out of 4 , always connect serial and parallel to always have 4ohm. I don't know why only 1 always breaks.
I do think it's really odd that Dayton Audio is not at all clear about how you are supposed to use the holes on some of their exciters. Many have the threaded hole on the back in the center, and/or the four unthreaded holes around the perimeter. They do describe the four holes on the 30HESF-4 as "screw down mounting tabs" which does sound self explanatory, but I don't recall ever seeing anyone use them like that.
Eric
Eric
Eric
They don't mention it in docs, on mine they where covered by a sticker, and according to soundimports they are for use during manufacturing and not intended for mounting.
So I think it seems clear that are not intended to be used at all, and exciters should actually be able to hold up themselves.
But it seems like I'm not the only one with the experience that they do need back support, so the Dayton's have a flawed design that we can try to work around by using other methods than the one suggested by manufacturer for mounting.
They don't mention it in docs, on mine they where covered by a sticker, and according to soundimports they are for use during manufacturing and not intended for mounting.
So I think it seems clear that are not intended to be used at all, and exciters should actually be able to hold up themselves.
But it seems like I'm not the only one with the experience that they do need back support, so the Dayton's have a flawed design that we can try to work around by using other methods than the one suggested by manufacturer for mounting.
Leob.
As far as I can remember, discussion about exciter mounting has been going on for about one and a half decades.
The fact that you were warned of this problem, but decided to go your own way is why you have damaged exciters.
Agreed that the manufacturers should make it clear how to mount them.
But it has been mentioned many many times ,by me, and also on this forum.
You can't blame the exciter.
It also seems clear to me why one out of four exciters on the single panel has problems.
I made a post and video of this probable cause.
Steve.
As far as I can remember, discussion about exciter mounting has been going on for about one and a half decades.
The fact that you were warned of this problem, but decided to go your own way is why you have damaged exciters.
Agreed that the manufacturers should make it clear how to mount them.
But it has been mentioned many many times ,by me, and also on this forum.
You can't blame the exciter.
It also seems clear to me why one out of four exciters on the single panel has problems.
I made a post and video of this probable cause.
Steve.
Not sure where you got that I was warned in advance Steve?
But that doesn't really matter. I spoke to the seller/distributor, and they have stated that they should not need support. If they say I have used it correctly if I used it unsupported, of course I blame the exciter if it breaks from being used unsupported?
But it is great if the community here has a workaround for the defect and people that have read the 11000+ posts here can avoid experiencing the same issue.
But that doesn't really matter. I spoke to the seller/distributor, and they have stated that they should not need support. If they say I have used it correctly if I used it unsupported, of course I blame the exciter if it breaks from being used unsupported?
But it is great if the community here has a workaround for the defect and people that have read the 11000+ posts here can avoid experiencing the same issue.
Leob.
This was a panel Christian made with a rigid spine support.
This subject keeps popping up.
It has been done like this for a reason .
This is an very old panel I have posted many times on this forum.
Steve.
