Eucy, I didn't mold these panels. That is a future project. I got the material from an old, destroyed 4' x 2' ice chest. The link below will explain it in more detail.
You very much should try it out if possible (please do!) as I think these are the closest to EPS as it gets but sound even better to me personally.
Post # 7,748 - https://www.diyaudio.com/community/...ll-range-speaker.272576/page-388#post-7208551
I just did what i intended to setup last night.
sorry Eucy 😭😂
I found an old battered about 5mm hd eps panel ,it seems I destroyed both 5mm panels😩.
I glued on the exciter yesterday , basically just stuck it on anywhere.
first pic is of the panel from the front, with a magnet attached to show where the exciter is.
second pic is the response, with the peak in the 10k region ,this is easily sorted without blu-tack.
third pic is the panel from the side angle used for the response plot.
The fourth pic is the response plot from the side angle , the microphone was behind my seating position where I took the pictures.
The response from the side angle looks better than the front, the peak at 10k needs getting rid of.
Not bad for an old battered panel, with the exciter stick on just anywhere.
If placed on a proper hd eps 5mm panel my exciters would give a very good broad frequency response .
Steve.
sorry Eucy 😭😂
I found an old battered about 5mm hd eps panel ,it seems I destroyed both 5mm panels😩.
I glued on the exciter yesterday , basically just stuck it on anywhere.
first pic is of the panel from the front, with a magnet attached to show where the exciter is.
second pic is the response, with the peak in the 10k region ,this is easily sorted without blu-tack.
third pic is the panel from the side angle used for the response plot.
The fourth pic is the response plot from the side angle , the microphone was behind my seating position where I took the pictures.
The response from the side angle looks better than the front, the peak at 10k needs getting rid of.
Not bad for an old battered panel, with the exciter stick on just anywhere.
If placed on a proper hd eps 5mm panel my exciters would give a very good broad frequency response .
Steve.
I have about 5 turntables none of them are hooked up at the moment as they all need some attention,as does my valve amp, I have spent far too long on the panels and have neglected them 😳
The whizzer I made had a good response from 2k up , so you would hear the response up to 8k with no problems.
That is why I thought of you, and thought it might help.
Getting old is a pain in the neck (literally) so hope you get well soon and get back to some good old diy 👍
Steve.
toddincabo, Can you please state the density, lbs/cubic foot or kg/cubic meter of this cooler poly foam? Also which excilter are you using?Thanks!
Sorry, I have no idea about lbs or kg's per, or even how to go about checking that, but as I explained in prior posts, the foam is really dense as I can squeeze it with my fingers as hard as I can and it barely squeezes in. Super light material though. The exciters are the cheap DAEX25FHE-4. My entire surround speakers are made of this material and these exciters.
I wish a few people could find a way to test some PU foam just to have some other opinions. What sounds good to me could be crap to others but would be cool to see someone graph some out.
I'm debating whether to splurge and order some of the more advanced steered flux DAEX25SHF-4's when I can catch them on sale, not sure if the $85 for two right now is really worth it. Input from anyone with knowledge on these would be greatly appreciated.
Luv em... Read my posts
And we pay about $90 EACH here so you get a bargain 👍
Check this link
https://www.wagneronline.com.au/sou...dio-speakers-pa/daex25shf-4-73057/1007143/pd/
I see the manufacturer's wholesale prices is less than US$20-00. But you have to order 1,000 at a time... sigh
I have used DAEX25SHF in a number of different projects. It’s powerfull and generates a clean sound extending up 20k.
The measurement is from the white round one. It’s an 8 inch panel playing both as DML/bending wave and pistonic i.e. a bmr.
The smaller round ”woodcoloured” is used as center speaker and lying flat on a bench which work very well due to the DML sound dispersion.
The measurements are from 1m.
It is a really nice exciter!
thomas
The measurement is from the white round one. It’s an 8 inch panel playing both as DML/bending wave and pistonic i.e. a bmr.
The smaller round ”woodcoloured” is used as center speaker and lying flat on a bench which work very well due to the DML sound dispersion.
The measurements are from 1m.
It is a really nice exciter!
thomas
Attachments
Thomas,
Are those BMR's as simple as they appear? Round CF sandwich panel with a normal surround, attached to round frame, with exciter mounted dead center via a spine? In the image below, the back of the panel looks different from the face. Is it just a different CF fabric, or is there more to it than that?
Very cool, as always.
Thanks,
Eric
Are those BMR's as simple as they appear? Round CF sandwich panel with a normal surround, attached to round frame, with exciter mounted dead center via a spine? In the image below, the back of the panel looks different from the face. Is it just a different CF fabric, or is there more to it than that?
Very cool, as always.
Thanks,
Eric
from the first tests of the fibre-nomex panel the result seems excellent, even if it has a better effectiveness on the very high frequencies on the side where the exciters are mounted, given that this part of the frequencies does not come from the vicinity of the exciter but from the edges of the panel always on the rear side.Do you notice this thing too?
OK I'm sold on the DAEX25SHF-4's. I'm gonna pull the trigger next time I have someone coming down to visit. I look forward to testing them against their cheap brethren. I'll use these for the R/L as they are my music speakers of course.
I think I'm going to set it up to where I can do an A/B blind sound test with the help of a friend so as not to placebo out towards the expensive one.
I think I'm going to set it up to where I can do an A/B blind sound test with the help of a friend so as not to placebo out towards the expensive one.
Could you please give an opinion of these compared to other exciters you have used if possible.
I was casually scanning through some comparisons today (trying to increase the WAF) when I was forced to suddenly curtail my walpoling activities after noticing this...
Here are two identical drivers from Dayton. the 25FHE, and the 25FHE2. The only difference between them being that the first is a common-or-garden type of driver, and the second has an interchangeable mount. Big deal?
No. I mean YES!
Here are their (Dayton) response curves (on a 12x12x1/2" foam-core board in an infinite baffle....)
In other words, the one with the interchangeable mount has a RESONANT CAVITY!!
Fascinating.
So, therefore, from the above, we know now that an extra 5mm cavity on top of a 25mmDia voice coil causes a peak at just over 10kHz.
Not only that, but the whole FR curve changes as well. I wonder if the same guy took those measurements.
Curiouser and curiouser.
Here are two identical drivers from Dayton. the 25FHE, and the 25FHE2. The only difference between them being that the first is a common-or-garden type of driver, and the second has an interchangeable mount. Big deal?
No. I mean YES!
Here are their (Dayton) response curves (on a 12x12x1/2" foam-core board in an infinite baffle....)
In other words, the one with the interchangeable mount has a RESONANT CAVITY!!
Fascinating.
So, therefore, from the above, we know now that an extra 5mm cavity on top of a 25mmDia voice coil causes a peak at just over 10kHz.
Not only that, but the whole FR curve changes as well. I wonder if the same guy took those measurements.
Curiouser and curiouser.
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But now we ALSO know that the cavity inside the VC has a significant effect on response levels around that frequency.
I think @spedge was doing something along these lines a while ago.
So, messing around with that VC cavity can change the HF. Plugs, damping, extenders etc should all make a difference.
Does it explain if or how inverted domes on the outside make a difference?
I think @spedge was doing something along these lines a while ago.
So, messing around with that VC cavity can change the HF. Plugs, damping, extenders etc should all make a difference.
Does it explain if or how inverted domes on the outside make a difference?
Intriguing yes. I would be cautious with data from the Dayton spec... those days, I was looking for the voice coil mass and spider stiffness of the different exciters... not well documented, many missing values, some units are wrong (confusion between mm/N and m/N), resonance frequency in the table that doesn't fit with the diagram, inductance value neither. So not a good quality documentation.
You are pointing to the right question : are the measurement conditions the same, same material?
Is it an effect of the cavity or of the panel area inside of the voice coil perimeter, or even both?
Easy to test though. Of course, there's also the thing of the added mass of the extention