Donthertzme.
Those are big panels, bigger than I expected.
It must have been messy work.
Anywhere between 40% and 50% pva and the rest water.
Just splash it on all over, the water will evaporate when dry , leaving the eps impregnated with a thin coating of pva.
When the exciter is glued to the panel the shout sound should reduce.
If not there are other methods to reduce this.
Does your exciter have a vent hole in its magnet .
Steve.
Those are big panels, bigger than I expected.
It must have been messy work.
Anywhere between 40% and 50% pva and the rest water.
Just splash it on all over, the water will evaporate when dry , leaving the eps impregnated with a thin coating of pva.
When the exciter is glued to the panel the shout sound should reduce.
If not there are other methods to reduce this.
Does your exciter have a vent hole in its magnet .
Steve.
Greetings Don'tHertzMe;
Glad to hear everyone is enjoying
I'm sure spedge can give you some very useful info. As to your closeness to the wall problem, have a read of post #761 , #993 and #995
Thank you for posting your results
Pete
It was insanely messy! But a great deal of fun. Thank you for the PVA recipe. The exciters I have are these (I've cut off the arms):
The hole has an M3 thread, so I assume it's for mounting. No hole on the front side.
Thank you for that - I have some speaker stuffing in a cupboard somewhere, will dig it out. I can buy melamine sponges, but we'll need a lot of them.
Donthertzme.
You can experiment by moving the panels back and forth towards the wall , and listening to the sound change , what sound you prefer is up to you.
Adding damping behind the panel will help, but buy how much I don't know, its a big panel , and it is very close to the wall, the natural rear sound will be lost.
A small panel might have given a better performance in this situation?
Such as the canvas panel or card panel.
but have fun.
Steve.
You can experiment by moving the panels back and forth towards the wall , and listening to the sound change , what sound you prefer is up to you.
Adding damping behind the panel will help, but buy how much I don't know, its a big panel , and it is very close to the wall, the natural rear sound will be lost.
A small panel might have given a better performance in this situation?
Such as the canvas panel or card panel.
but have fun.
Steve.
Steve,
Thanks for direct me to those old post. I will read them.
Yes I did listen some of your recordings. They sounds good! However I can't project those panel's "real sound" from records.
I'm now listening your "epoxy coated 5mm xps" and "1cm eps low grade" mp3.
Your XPS sounds much natural then all XPS I tested. However I'm not sure your XPS is it same good sounding if I actually listen them.
Just listen your recordings I can't get a clear picture of their quality. However it's good for compare 2 of your panels their "difference". They are both recorded under the same condition so I can get a picture of their difference.
I doubt that you're using phone to record? External mic for sure right? How to get the stereo so good!
Christian,
Shame that I don't have enough knowledge to read those patents. I gave back all the maths to my teacher. Now I even forget how to make simply calculation by pen and paper.
An update: I'm still can't find a fit size bottle cap to try the screw mount system. And I've got enough exciters to pair with my final panels. So this project may not be done in a near future.
Eucy,
I'm agree we should try to get some "common scale".
I think crushability may not easy to measure without a proper equipment. Coin with weight is easy to process but seems not easy to measure. The indents maybe 0.1mm count I guess.
DontHertzMe,
It's a pleasure to know you get the success and satisfaction on first try. And I'm really jealous you can enjoy the DIY with your girls! I'm always DIM.
Thanks for direct me to those old post. I will read them.
Yes I did listen some of your recordings. They sounds good! However I can't project those panel's "real sound" from records.
I'm now listening your "epoxy coated 5mm xps" and "1cm eps low grade" mp3.
Your XPS sounds much natural then all XPS I tested. However I'm not sure your XPS is it same good sounding if I actually listen them.
Just listen your recordings I can't get a clear picture of their quality. However it's good for compare 2 of your panels their "difference". They are both recorded under the same condition so I can get a picture of their difference.
I doubt that you're using phone to record? External mic for sure right? How to get the stereo so good!
Christian,
Shame that I don't have enough knowledge to read those patents. I gave back all the maths to my teacher. Now I even forget how to make simply calculation by pen and paper.
An update: I'm still can't find a fit size bottle cap to try the screw mount system. And I've got enough exciters to pair with my final panels. So this project may not be done in a near future.
Eucy,
I'm agree we should try to get some "common scale".
I think crushability may not easy to measure without a proper equipment. Coin with weight is easy to process but seems not easy to measure. The indents maybe 0.1mm count I guess.
DontHertzMe,
It's a pleasure to know you get the success and satisfaction on first try. And I'm really jealous you can enjoy the DIY with your girls! I'm always DIM.
Hkguy6
The picture in this post shows the the rug I used to record my headphones recordings .
The last recording was done in exactly the same way , but I held my Samsung a12 phone in my hand instead of resting on the rug.
This way I do not need the low frequency drivers, as the panels produce full range nearfield response.
All other previous recordings were recorded at 1m in front of the panels.
With the low frequency drivers, unless stated otherwise.
The 5mm is a totally different panel when coated in epoxy, it actually sounds good.
It sounded OK with the pva coating but xps has problems with the higher frequencies, the epoxy sorts this out.
But it is no longer a light panel.
I was thinking at some time in the future, to use the scraping method of applying the epoxy to see if I could get a thinner coating ,rather than the roller ,which I felt was too thick and heavy ?
The 2ft proplex panels are the only serious full range panels that I would be happy playing loud rock music without a sub.
They just need more powerful exciters.
Steve.
Hkguy6.
The idea behind using the headphones method ,was so that you could hear the panel sound only ,without trying to blend in the low frequency drivers , which is a pain trying to get right, as I only know if I got it right ,after the recording has been done.
You can end up doing several recordings before you finally get it right , but it will never be perfect.
This way you only hear the panel sound,warts and all, not the room or the low frequency drivers.
Steve.
Steve.
The idea behind using the headphones method ,was so that you could hear the panel sound only ,without trying to blend in the low frequency drivers , which is a pain trying to get right, as I only know if I got it right ,after the recording has been done.
You can end up doing several recordings before you finally get it right , but it will never be perfect.
This way you only hear the panel sound,warts and all, not the room or the low frequency drivers.
Steve.
Steve.
Donthertzme.
I only asked about the hole, as there is a modification I make to the panel , which I will cover in the graphite panel tests.
I can do this with my exciter after it is glued to the panel and show the difference.
But you will have to do it before gluing on the exciter as you do not have the hole.
A lot of panels have a peak somewhere near 10k with dips each side, mostly above, with a drop off in frequency there after.
Tectonic panels included!
It is just an easy remedy.
But not totally necessary, but should help prevent some of the shoutyness and most of all sibilance.
Steve.
I only asked about the hole, as there is a modification I make to the panel , which I will cover in the graphite panel tests.
I can do this with my exciter after it is glued to the panel and show the difference.
But you will have to do it before gluing on the exciter as you do not have the hole.
A lot of panels have a peak somewhere near 10k with dips each side, mostly above, with a drop off in frequency there after.
Tectonic panels included!
It is just an easy remedy.
But not totally necessary, but should help prevent some of the shoutyness and most of all sibilance.
Steve.
I thought I would take a few pictures of the panel response to give you all an idea of what I am doing.
The first pic is of the response about 2inches in front of the exciter area.
The 10k peak on this material is well damped.
The second pic is of the microphone being moved around about 2inches in front of the panel on peak hold, but around the edges, 2inches in from the sides.
It is at a lower level but quite similar but a more heavy a drop after 10k.
The third pic is with the microphone in a fixed position at 3m in my seating position.
I gave up trying to get a better response as there was a lot of passing traffic noise and my dog barking which was driving me mad.🤯
At the moment I am more interested in the response above 10k although it is pretty consistent from about 400hz to 10k, very similar to some measurements I made over ten years ago with my large eps panels over on NXT RUBBISH.
The suck out in the 100hz to 400hz region, is not that great, but this is a fixed point measurement which does not give a true idea what is going on in this area.
All the rubbish in my room is not helping the in room response either.
Anyway, even though I can't see a large peak at 10k to remove, I will see if I can still increase the hf, or not ?
Steve.
The first pic is of the response about 2inches in front of the exciter area.
The 10k peak on this material is well damped.
The second pic is of the microphone being moved around about 2inches in front of the panel on peak hold, but around the edges, 2inches in from the sides.
It is at a lower level but quite similar but a more heavy a drop after 10k.
The third pic is with the microphone in a fixed position at 3m in my seating position.
I gave up trying to get a better response as there was a lot of passing traffic noise and my dog barking which was driving me mad.🤯
At the moment I am more interested in the response above 10k although it is pretty consistent from about 400hz to 10k, very similar to some measurements I made over ten years ago with my large eps panels over on NXT RUBBISH.
The suck out in the 100hz to 400hz region, is not that great, but this is a fixed point measurement which does not give a true idea what is going on in this area.
All the rubbish in my room is not helping the in room response either.
Anyway, even though I can't see a large peak at 10k to remove, I will see if I can still increase the hf, or not ?
Steve.
Attachments
You means you're just place the a12 phone on that middle "roll of sheet"?!
Anyway, I just can't believe a phone's internal mic has this quality. Most of them won't capture bass at all. But your recordings obviously is full range.
Beside the mic quality, I can't imagine the mic has enough separation to record L/R stereo so good.
I have to test this on my phone, however I'm quite sure the result must not like yours.
Hkguy6.
Yes ,the phone is just propped up between the panels as if your head is in-between the panels.
I have always said even with my very large eps panels that standing between them was like wearing very large headphones .
I used to compare this sound to my headphones , and still do, the panels sounded better.
the microphones in the Samsung phones sound very good .
I did try various microphones with the computer but without much success.
They were very noisy with poor frequency responses.
The low frequency does roll off early on the Samsung phones though, there is nothing below 50hz.
The microphones in the phone are nearly 7 inches apart, very similar to our ears (maybe a little of the binaural sound ?).
At the moment I am using AudioLab free to record the stereo sound then using VLC to upload to my drive, where I can access and ZIP before uploading.
Not all phones are capable of stereo recordings.
The only problem is the auto volume control of the phone, which can become very intrusive, ruining the recordings sometimes.
Steve.
Yes ,the phone is just propped up between the panels as if your head is in-between the panels.
I have always said even with my very large eps panels that standing between them was like wearing very large headphones .
I used to compare this sound to my headphones , and still do, the panels sounded better.
the microphones in the Samsung phones sound very good .
I did try various microphones with the computer but without much success.
They were very noisy with poor frequency responses.
The low frequency does roll off early on the Samsung phones though, there is nothing below 50hz.
The microphones in the phone are nearly 7 inches apart, very similar to our ears (maybe a little of the binaural sound ?).
At the moment I am using AudioLab free to record the stereo sound then using VLC to upload to my drive, where I can access and ZIP before uploading.
Not all phones are capable of stereo recordings.
The only problem is the auto volume control of the phone, which can become very intrusive, ruining the recordings sometimes.
Steve.
Hkguy6.
Usually I record with the phone at about 1m in front of the panels ,with the panels at about 1m apart.
This prevents most room sounds(noise), but it is very difficult to get the blend right, being so close to the low frequency drivers.
Recording with just the panels playing is so much easier.
And you don't have to worry about the cross over , you only hear the panels, nothing is masking the sound.
But obviously this is only the near field response and the low frequencies will drop away the further away you move.
But this is the sound you will have in your seating position if you blend in your low frequency properly.
Steve.
Usually I record with the phone at about 1m in front of the panels ,with the panels at about 1m apart.
This prevents most room sounds(noise), but it is very difficult to get the blend right, being so close to the low frequency drivers.
Recording with just the panels playing is so much easier.
And you don't have to worry about the cross over , you only hear the panels, nothing is masking the sound.
But obviously this is only the near field response and the low frequencies will drop away the further away you move.
But this is the sound you will have in your seating position if you blend in your low frequency properly.
Steve.
Forgive I'm so dumb to think phone mic are placed left and right bottom. Now I know they are top and bottom.
Yes I also have my "large headphone". (pic)
They are not the best sound setting. My ears always prefer single excitor and 2 panels clean imaging. However this 4 small panels setting is really good for late night listening. So intimate but with a huge deep soundstage.
Attachments
Aiyima Exciters
Does anyone have experience with these Exciters... They have an aluminium mounting plate and rod which would seem to me to be heavy enough to affect hf frequency response
Also they have the metal spring spider which seems not ideal to me
They do however come in a range of powers and are reasonably priced
So worth a try maybe?
Does anyone have experience with these Exciters... They have an aluminium mounting plate and rod which would seem to me to be heavy enough to affect hf frequency response
Also they have the metal spring spider which seems not ideal to me
They do however come in a range of powers and are reasonably priced
So worth a try maybe?
I've got 3 models of them.
Yes you're right the metal spider is too stiff. So I cut them (pic2), however sounds not much improve.
Other problem is, from the pic1 you can see both 44/50mm model share the exact same spider. So the 44mm even worst sounding then the 50mm.
And they're both too heavy to use on a spineless system.
Overall not recommand even they're cheap.
