Chris Isaak wicked game
57buick.
quickly did a recording ,right chanel only ,not mono so might sound a bit strang.
first half at one metre then 3 mtr ,the fr of the panel is 40hz to 20k.
the top end sounds a bit harsh because of the cascamite ,gives it a glassy sound,a little too rigid i think,the cracking didnt help.
steve
57buick.
quickly did a recording ,right chanel only ,not mono so might sound a bit strang.
first half at one metre then 3 mtr ,the fr of the panel is 40hz to 20k.
the top end sounds a bit harsh because of the cascamite ,gives it a glassy sound,a little too rigid i think,the cracking didnt help.
steve
Wow so just hooked up my canvas for the first time and wow Im impressed!
18x24 canvas, coated backs with PPG gripper acrylic primer. Also used the gripper to paste these 3 ply birch circles to mount the exciters onto.
Im using a home receiver that is supposed to take 8ohm speakers and Im running a single 4ohm exciter on each at moment. I have a 100w powered sub under the desk that is just barely has the level turned up maybe 2 nothes and I am not using any equalizer.
I am using my iphone to test the audio signal with a MP3 of pink noise -12db I got off the internet somewhere and these are the results I got. granted the iphone is not going to be as accurate as you audiophiles equipment but look at that spectrum all the way from the low end to the high end.
First is without the sub level on at all and the second is turning the sub on just slightly.
I think that is pretty impressive.
Now that these are successful Im gonna have some canvas with pictures of my kids made to hang in the house as speakers.
18x24 canvas, coated backs with PPG gripper acrylic primer. Also used the gripper to paste these 3 ply birch circles to mount the exciters onto.
Im using a home receiver that is supposed to take 8ohm speakers and Im running a single 4ohm exciter on each at moment. I have a 100w powered sub under the desk that is just barely has the level turned up maybe 2 nothes and I am not using any equalizer.
I am using my iphone to test the audio signal with a MP3 of pink noise -12db I got off the internet somewhere and these are the results I got. granted the iphone is not going to be as accurate as you audiophiles equipment but look at that spectrum all the way from the low end to the high end.
First is without the sub level on at all and the second is turning the sub on just slightly.
I think that is pretty impressive.
Now that these are successful Im gonna have some canvas with pictures of my kids made to hang in the house as speakers.
Attachments
Last edited:
57buick.
I presume that is the steering wheel of a 57 buick in the photo?
At first I thought it was some crazy art work welded together,couldn't figure it out,then The penny droped.
The iPhone microphone will probably be restricted in the highs and lows ,but from your pictures of the eps it gives a good response down to about 40hz.
You could try what I am doing with new panels with the exciter more central,or maybe mount the exciter on to a spine to help prevent exciter sag ,on the canvas as well as the coils ,and maybe drive the panel better in the low end?,I presume they are in piston mode at this point? My panels are very stiff in the central area with the cascamite and the 4x6inch bulsa ply.
I will test with clamps and some blu-tack .
Steve
I presume that is the steering wheel of a 57 buick in the photo?
At first I thought it was some crazy art work welded together,couldn't figure it out,then The penny droped.
The iPhone microphone will probably be restricted in the highs and lows ,but from your pictures of the eps it gives a good response down to about 40hz.
You could try what I am doing with new panels with the exciter more central,or maybe mount the exciter on to a spine to help prevent exciter sag ,on the canvas as well as the coils ,and maybe drive the panel better in the low end?,I presume they are in piston mode at this point? My panels are very stiff in the central area with the cascamite and the 4x6inch bulsa ply.
I will test with clamps and some blu-tack .
Steve
Yea Im gonna try a spline and see what that does, hopefully give a little more spl too. I was just impressd with what a simple setup could do. Now to start fine tuning.
The steering wheel is actually from an old 55 Chevy Nomand that was my dads car when he was a kid.
57buick.
Some fr response pic with spine, I should have taken some pics before adding the spine,don't think it's changed much though.
Once again sorry for the poor picture quality,my other tablet has packed up so this is all i've got.
Still not a lot below 40hz,I don't think the 10watt exciter has enough power to move the panel below this,it's hit a brick wall.
First photo at 1mtr second at 3mtr the peek in the 400to 500hz lower mid is the annoying sound of the cascamite I think?
But apart from this the response is within +and-5db from 20k until 100hz when the response increases between 5and 10db till it drops like a stone at 40hz.
The dip at about 200hz, which is worse 3mtrs into the room ,is the room suckout ,even my TLS suffer from this.
Not bad for something so simple to make,as you say surprising how good (large) it sounds for such a small panel.
Sometime ago I tried two 15 inch drive units without cabinets to see how they performed,don't remember them producing this much low end and that was with two units?
And they were just running below 400hz.
Also this panel is 3ft off the floor and 3ft from the wall.
Steve
Some fr response pic with spine, I should have taken some pics before adding the spine,don't think it's changed much though.
Once again sorry for the poor picture quality,my other tablet has packed up so this is all i've got.
Still not a lot below 40hz,I don't think the 10watt exciter has enough power to move the panel below this,it's hit a brick wall.
First photo at 1mtr second at 3mtr the peek in the 400to 500hz lower mid is the annoying sound of the cascamite I think?
But apart from this the response is within +and-5db from 20k until 100hz when the response increases between 5and 10db till it drops like a stone at 40hz.
The dip at about 200hz, which is worse 3mtrs into the room ,is the room suckout ,even my TLS suffer from this.
Not bad for something so simple to make,as you say surprising how good (large) it sounds for such a small panel.
Sometime ago I tried two 15 inch drive units without cabinets to see how they performed,don't remember them producing this much low end and that was with two units?
And they were just running below 400hz.
Also this panel is 3ft off the floor and 3ft from the wall.
Steve
Attachments
OffGridKindaguy.
I've just searched through this site and finally found it was offGrid that came up with this idea.
Credit where it's due.
I know there is a patent for something similar,but this is such an easy work around and probably sounds just as good.
Steve
I've just searched through this site and finally found it was offGrid that came up with this idea.
Credit where it's due.
I know there is a patent for something similar,but this is such an easy work around and probably sounds just as good.
Steve
Just an FYI, if your in the market for a measuement Mic, PartsExpress has their UMM-6 (usb corded) for $76 and change...great bargain...plug it in to your computer, run REW, add in the calibration file and measure away 🙂
geosand
geosand
Patent WO2019061685A1
I tried to type in this patent I posted back on page 193 and it didn't work! It does not seem to exist anymore?
I presume no one has managed to access this,it is basically very similar to the picture panel although they say it can reach down to 20hz?
After a few days trying to find it I managed to find a work around that shows the patent.
So if it does not work for you try typing in parent CN201118973Y and scroll down to cited patents and you will find the patent listed there,click on it and hey presto there it is(I hope).
If it does work maybe someone could kindly post an easy link that works?
The fabric is woven Kevlar but it has a rubber type gasket between the bulsa and the Kevlar? Supposedly to help LF and blend the frequencies?
If this patent works as said ,it seems strange that it never made it into production(or did it?)'
A small panel that has a response from 20HZ to 20 or 25K seems unthinkable,impossible!
Surely this would have taken the audio world by storm?
I suppose we'll just have to live with the artists picture frames instead?
All the best .
Steve
I tried to type in this patent I posted back on page 193 and it didn't work! It does not seem to exist anymore?
I presume no one has managed to access this,it is basically very similar to the picture panel although they say it can reach down to 20hz?
After a few days trying to find it I managed to find a work around that shows the patent.
So if it does not work for you try typing in parent CN201118973Y and scroll down to cited patents and you will find the patent listed there,click on it and hey presto there it is(I hope).
If it does work maybe someone could kindly post an easy link that works?
The fabric is woven Kevlar but it has a rubber type gasket between the bulsa and the Kevlar? Supposedly to help LF and blend the frequencies?
If this patent works as said ,it seems strange that it never made it into production(or did it?)'
A small panel that has a response from 20HZ to 20 or 25K seems unthinkable,impossible!
Surely this would have taken the audio world by storm?
I suppose we'll just have to live with the artists picture frames instead?
All the best .
Steve
Geosand.
I did look in to microphones for measuring and recording but in the end I realized that the only use they would be to me was for posting on this site!
So most of the time the usb Mic would just sit there I'm afraid.
I need a new measurement Mic for my deq as the one I have at the moment has had a hard life(many times it has gone flying past me because my foot has got caught up in the lead).
But thanks for the info,you never know.
Steve
I did look in to microphones for measuring and recording but in the end I realized that the only use they would be to me was for posting on this site!
So most of the time the usb Mic would just sit there I'm afraid.
I need a new measurement Mic for my deq as the one I have at the moment has had a hard life(many times it has gone flying past me because my foot has got caught up in the lead).
But thanks for the info,you never know.
Steve
This is a graph of my panels reaching down to 20Hz. The problem is room modes in the long wavelength bass region (below Schroeder.) My speakers generate low frequencies but my walls, ceiling, and floor cause the long wavelengths to interfere with one another and cancel out or peak in different parts of the room.
To reduce low frequency cancellations and peaks you'd just need multiple panels (multiple subs) positioned and equalized for low frequency modes using a strategy supplied by Harman/Welti or Earl Geddes.
The Geddes Multi-Subwoofer Bass Optimization Approach - YouTube
Attachments
KoAP.
Thank you once again,is it me or is this starting to get embarrassing?
Is there any chance you could pm me with instructions on how to do this myself ,with the emphasis on how to post links for idiots!
Burntcoil has already had to show me how to upload pics.
Maybe I need to go on some sort of training course?
Bradleypnw.
Luckily running my LF drivers above the room dip and my panels below the dip ,so I have four drivers covering the dip and it seems to cancel the dip very well.
I do have a theory as to why this works so well with dml panels but I'm not sure.
My LF speakers are a foot of two further back and a foot of two to the side in the corner, I normally use time delay to time align the panels,although because I'm always changing panels it gets missed sometimes.
Steve
Thank you once again,is it me or is this starting to get embarrassing?
Is there any chance you could pm me with instructions on how to do this myself ,with the emphasis on how to post links for idiots!
Burntcoil has already had to show me how to upload pics.
Maybe I need to go on some sort of training course?
Bradleypnw.
Luckily running my LF drivers above the room dip and my panels below the dip ,so I have four drivers covering the dip and it seems to cancel the dip very well.
I do have a theory as to why this works so well with dml panels but I'm not sure.
My LF speakers are a foot of two further back and a foot of two to the side in the corner, I normally use time delay to time align the panels,although because I'm always changing panels it gets missed sometimes.
Steve
@ Spedge
Dayton too happen to have a good measurement mic which is very good value, IMHO. Check to see if its available from the usual sources for less, which is likely.
Dayton Audio - EMM-6 Electret Measurement Microphone
Warm regards
Dayton too happen to have a good measurement mic which is very good value, IMHO. Check to see if its available from the usual sources for less, which is likely.
Dayton Audio - EMM-6 Electret Measurement Microphone
Warm regards
I found this article that gives step by step instructions on how to equalize a DML panel using REW.
Originally, I made manual adjustments through the DSP. REW's automated EQ is a lot faster.
Digital Signal Processing (DSP) to Equalize DML Speakers
Originally, I made manual adjustments through the DSP. REW's automated EQ is a lot faster.
Digital Signal Processing (DSP) to Equalize DML Speakers
Bradleypnw.
Apart from the rew tutorial ,the rest of the site is a bit of a mystery to me ,2inch polystyrene 3x4ft ,throwing a fluffy towel over the panel and turning the treble down to control the exclusive hump (20db )in the response?
Or use expensive dsp ?
Why not just design a panel that has a good response to start with?
100 to 200hz or so up to 20k should be no problem with a little effort.
Steve
Apart from the rew tutorial ,the rest of the site is a bit of a mystery to me ,2inch polystyrene 3x4ft ,throwing a fluffy towel over the panel and turning the treble down to control the exclusive hump (20db )in the response?
Or use expensive dsp ?
Why not just design a panel that has a good response to start with?
100 to 200hz or so up to 20k should be no problem with a little effort.
Steve
On the other hand ,polystyrene is very cheap and 2inch with canvas covering will be quite robust for church use.
He suggests using many panels ,do they eq each panel separately?
I suppose finding a panel with a smooth hump in the response might be easier to eq down ,than one with a jagged response that is all over the place?
I do have a 2inch polystyrene panel in the loft but can't remember the response,the fact that it is in the loft probably says it all.
But it obviously does the job and by the sound of what he says,it does it well.
The flexibility of dml is very interesting.
It's just choosing which one is right for you I suppose.
Steve
He suggests using many panels ,do they eq each panel separately?
I suppose finding a panel with a smooth hump in the response might be easier to eq down ,than one with a jagged response that is all over the place?
I do have a 2inch polystyrene panel in the loft but can't remember the response,the fact that it is in the loft probably says it all.
But it obviously does the job and by the sound of what he says,it does it well.
The flexibility of dml is very interesting.
It's just choosing which one is right for you I suppose.
Steve
REW frequency response graphs are few and far between in this thread. I'm going to go out on a limb and say building passive DMLs with good frequency response requires a tremendous amount of effort. In contrast, taming DML frequency response with DSP is easy.