As "Tech Ingredients" initially demonstrated in their DML series videos, the purpose of using different materials as acoustic ceiling tiles, is to obtained a much rounded & richer sound when used in conjunction with other materials. What I gathered is that materials, sizes, thickness and location of exiter are only some variables, that will dictate frequency ranges. The reason why DML projects makes this DIY so intriguing, is since with the variables involved, it will bring out a uniquely different, creative experience by experimenting. EDIT: Most recently, they conducted a 5.1 setup by complete isolating and sorrounding the ear's perspective and at the same time showed how it can project sound outward on to an open space from it's back side. This really proves the potential of this panels on a large open area configuration.
Hi madmaxd1, regarding " the purpose of using different materials as acoustic ceiling tiles, is to obtained a much rounded & richer sound" I disagree with that: the purpose of using different materials, as stated by Tech Ing., was to - paraphrasing - "get frequency combs to overlap and thereby create a flatter response curve." if you mix foam and ceiling panels in an effort to do this it won't work because the foam panels are so much louder. This is why in a subsequent video, Tech Ing. used different amplifiers to power the foam and ceiling panels, sending low power to the foam, and higher power to the ceiling tiles so that their loudness's would be closer. I find this to be a bit silly. why work so hard to make a bad material (the ceiling tiles) be less bad? foam panels are better, honeycomb cardboard and end grain balsa is likely better than ceiling tiles. The density of the ceiling tiles is just too high. There are other ways go get the frequency combs to overlap in a positive way, using panel shape, and exciter location for example. But yes, the creative possibilities DML panels are quite inviting.
About your "poorly" performed ceiling tiles. The tiles are heavier therefore they need more power to generate a given amount of sound. The thing to notice is not the lower output you got, but that you DID get better low-end sound with the ceiling tiles. That is all that was demonstrated by Tech Ingredients as well. The solution for anyone wanting to replicate your work is to use a more powerful exciter. You used the 24W. I suggest using Dayton's 40W on the ceiling tiles. That said, after a review of posts on DML speakers, one would have to come to the conclusion that a subwoofer is going to be needed anyway, so the larger size panels (ceiling or foam) do not really add much value. Thanks for sharing.
@jeffkirk4761 I noticed the same thing about power. I want to build a DML set to act as central channel on my surround system for the voices. I'm wondering what would be best given I do have a subwoofer. Before reading your comment I though the best would be a 2'x4' ceiling tile with a 40w exciter in series with a 2'x2' polystyrene with a 25w. To achieve that "more balanced response" TI mentioned. It seems his 4 panel combination is overkill to get a good result. It's such a shame he did not run an REW test of the combined panels instead of playing us music... After your comment I'm wondering weather or not I should just used a smaller ceiling tile (for visual effect)
I ended up with this setup: Dayton Audio EX32EP2-4 Thrusters, FOAMULAR NGX 1 in. x 2 ft. x 2 ft. panels, Fosi Audio BT30D Amplifier, Infinity HTS-10 subwoofer. The panels are inside a light fabric “case” that my wife sewed together. We have them hooked to our TV. I am not an audiophile and rarely listen to music. I am so glad I did this. The realism is everything I expected. The only issue I have is that the exciters I got are heavier than I expected. Placed at the 3/5ths location, the panels don’t hang straight. The top is 2.5” away from the wall while the bottom is 3”. I think a small ceiling tile may have worked better. @@Turri_Moreira
They sound good because you built them to your specs. I wouldn't disregard the ceiling tiles. Your graph is telling you they need more power. I have a very similar fosi amp and i love it, but I dont think it can push the heavier tiles, but I'm also guessing 🤪 Thanks so much for posting this! Answered some questions I had and inspired me to order some parts 🙏
Very good video, and thanks! BTW, it is often called the "Golden Mean", "Fibonacci Proportion", "Fibonacci Ratio", "Golden Ratio", or other related descriptive term (i.e. it's not "Golden Rule", that's "do onto others as...")
Hi, I am sure I have made that measurement, but I am out of town right now, and I don't have the laptop I use for audio testing with me. How should I get it to you? I could email it, or post it on facebook, later, after I get home. I could also just tell you about it. In general, if I recall correctly, regarding the foam panels only, the high end drops off a bit after 14 kHz, and the low starts to drop near 70 Hz. You can email me if you like at henrydegroh@gmail.com
Thanks man! Finally someone did some REW testing with them! Have been searching for this for some time! I wonder if you tested one polystyrene and one accoustic tile in series to see how their combined work looks on REW. TI used a 40w for the ceiling tile which could give you better volume for that one
Yes, I did try that (one foam tile in series with a ceiling tile) the "problem" is the foam is about 3 times louder, thus the ceiling tile contributes VERY little. you basically can't hear the ceiling tile because the foam is so much more efficient (louder). Why work hard to make something that works poorly work better? when you already have something that works WAY better?
Thank you very much for the interesting video! I am contemplating making some myself. I see folks in the US mostly work with the 1inch thickness XPS panels Since i live in metric land, we only have 20mm and 30mm panels available. Would you recommend going up or down in thickness? It might be negligable difference. Still wanted to ask!
I don't have any data on how the thickness affects performance. This material is not very strong. My panels are larger than some are building. If your making large panels (greater than 2 ft x 2 ft) I would go thicker. Maybe thinner would work better when building smaller panels.
The DML panels are very loud (high SPL) but the output drops off a bit at the higher frequencies, so although the highs are there and strong, they are not as loud as the mid-frequencies, thus yes, I do a very primitive EQ in the tests I did on these: which consisted of turning up the treble knob while keeping the bass know flat.
Placement- A bass boost from wall proximity of speaker panel would be convenient, as panels hanging in the middle of a room is likely untenable for most ppl. Did you test or have an opinion, thank you.
I have seen some applications where the person hung them up overhead in a cathedral ceiling area; but my tests were done with the panels rather close to the wall: one was about 2', the other at an angle to the wall, 3' away. their performance was similar. They are designed to be hung close to a wall, like next to your tv or something. some people have hung them in an open deep frame with rockwool sound absorbing insulation in the box to absorb most of the sound coming from the rear of the panel.
You have asked a very valid question.. I have started experimenting with these types of speakers after watching many how-to videos and can tell you there's a major difference in sound quality depending on proximity to the back wall.. What I can suggest is what I did, have a listener in the area where you would be listening from and another person move the speaker further away and closer while playing music. In this manner you can find the sweet spot where the interaction makes the best sound. Hope this helps!
Each panels uses a 4 Ohm exciter. If you use two on each side wired in series 8 Ohms will result. Then you could add two more panels to each side and wire the two pairs in parallel, going back to 4 Ohms. So yes, you can add more panels. Is this clear?
Something is wrong with the sub measurement! How can it have high frequency!!! on a sub woofer!!! other than that, great job for sharing your experiences.
In the video, I misspoke: The subwoofer sweep includes the panels. It is meant to show the response of the panels and the sub working together. The sub was off for the sweeps I show for the panels.
@@VEC7ORlt Maybe I'm wrong.(?) It seemed to me that Henry de Groh built it with the same materials, same rounded corners, same two fifth/three fifth ratio like TI. So lets ask him: Sir, have you been inspired to this build by Tech Ingredients? And if so, would you mind giving them credit?
Very interesting although i can guarantee you that there is a huge amount of toxic microparticles released in the air from the vibration of those panels. That meterial was never intended to be excited in its structure. For people that have them at home it might be a good idea to wrap them in a sheet like cloth… sounds shouldn’t be affected too much.
What toxic microparticles are you talking about? These panels are 100% non toxic (extruded) polystyrene. And how would it "release" any microparticles do you reckon?!? Please don't spread misinformation. We already have so many toxins in and around us or in our food, to worry about.
i have an idea! Try sticking a couple ounces of wheel weights to the back of the exciter. It might lower frequency response. i have done similar with normal speakers by adding weight to the cone & lowering the resonance frequency. That eliminated the need for a subwoofer.
@@henrydegroh2341 Alloy wheel weights are very cheap, are easy to cut to weight, & have double-stick super-tape pre applied. I bet a single strip (~2oz) will be under $5, even free if you know a mechanic.
@@Iowa599 the back of 24 watt exciters I use have a tapped hole in them at the back, so you could attach it with a screw so it could be easily removed/changed.
I bet it will have no effect on higher frequencies, because adding mass will lower the resonance frequency of the exciter, only. that is just a theory, though...adding mass to the cone of normal speakers (coax with the tweeter removed, superqlued oil cap cone ;) ) worked to avoid a subwoofer, but I also installed a 100hz low pass crossover.
As "Tech Ingredients" initially demonstrated in their DML series videos, the purpose of using different materials as acoustic ceiling tiles, is to obtained a much rounded & richer sound when used in conjunction with other materials. What I gathered is that materials, sizes, thickness and location of exiter are only some variables, that will dictate frequency ranges. The reason why DML projects makes this DIY so intriguing, is since with the variables involved, it will bring out a uniquely different, creative experience by experimenting.
EDIT: Most recently, they conducted a 5.1 setup by complete isolating and sorrounding the ear's perspective and at the same time showed how it can project sound outward on to an open space from it's back side. This really proves the potential of this panels on a large open area configuration.
Hi madmaxd1, regarding " the purpose of using different materials as acoustic ceiling tiles, is to obtained a much rounded & richer sound" I disagree with that: the purpose of using different materials, as stated by Tech Ing., was to - paraphrasing - "get frequency combs to overlap and thereby create a flatter response curve." if you mix foam and ceiling panels in an effort to do this it won't work because the foam panels are so much louder. This is why in a subsequent video, Tech Ing. used different amplifiers to power the foam and ceiling panels, sending low power to the foam, and higher power to the ceiling tiles so that their loudness's would be closer. I find this to be a bit silly. why work so hard to make a bad material (the ceiling tiles) be less bad? foam panels are better, honeycomb cardboard and end grain balsa is likely better than ceiling tiles. The density of the ceiling tiles is just too high. There are other ways go get the frequency combs to overlap in a positive way, using panel shape, and exciter location for example. But yes, the creative possibilities DML panels are quite inviting.
About your "poorly" performed ceiling tiles. The tiles are heavier therefore they need more power to generate a given amount of sound. The thing to notice is not the lower output you got, but that you DID get better low-end sound with the ceiling tiles. That is all that was demonstrated by Tech Ingredients as well. The solution for anyone wanting to replicate your work is to use a more powerful exciter. You used the 24W. I suggest using Dayton's 40W on the ceiling tiles. That said, after a review of posts on DML speakers, one would have to come to the conclusion that a subwoofer is going to be needed anyway, so the larger size panels (ceiling or foam) do not really add much value. Thanks for sharing.
@jeffkirk4761 I noticed the same thing about power. I want to build a DML set to act as central channel on my surround system for the voices. I'm wondering what would be best given I do have a subwoofer.
Before reading your comment I though the best would be a 2'x4' ceiling tile with a 40w exciter in series with a 2'x2' polystyrene with a 25w. To achieve that "more balanced response" TI mentioned. It seems his 4 panel combination is overkill to get a good result. It's such a shame he did not run an REW test of the combined panels instead of playing us music...
After your comment I'm wondering weather or not I should just used a smaller ceiling tile (for visual effect)
I ended up with this setup: Dayton Audio EX32EP2-4 Thrusters, FOAMULAR NGX 1 in. x 2 ft. x 2 ft. panels, Fosi Audio BT30D Amplifier, Infinity HTS-10 subwoofer. The panels are inside a light fabric “case” that my wife sewed together. We have them hooked to our TV. I am not an audiophile and rarely listen to music. I am so glad I did this. The realism is everything I expected. The only issue I have is that the exciters I got are heavier than I expected. Placed at the 3/5ths location, the panels don’t hang straight. The top is 2.5” away from the wall while the bottom is 3”. I think a small ceiling tile may have worked better. @@Turri_Moreira
They sound good because you built them to your specs. I wouldn't disregard the ceiling tiles. Your graph is telling you they need more power. I have a very similar fosi amp and i love it, but I dont think it can push the heavier tiles, but I'm also guessing 🤪 Thanks so much for posting this! Answered some questions I had and inspired me to order some parts 🙏
Very good video, and thanks!
BTW, it is often called the "Golden Mean", "Fibonacci Proportion", "Fibonacci Ratio", "Golden Ratio", or other related descriptive term (i.e. it's not "Golden Rule", that's "do onto others as...")
Nice demo music!
Would you mind doing a Fresponse measurement without Sub and without EQ?
Hi, I am sure I have made that measurement, but I am out of town right now, and I don't have the laptop I use for audio testing with me. How should I get it to you? I could email it, or post it on facebook, later, after I get home. I could also just tell you about it. In general, if I recall correctly, regarding the foam panels only, the high end drops off a bit after 14 kHz, and the low starts to drop near 70 Hz. You can email me if you like at henrydegroh@gmail.com
Thanks man! Finally someone did some REW testing with them! Have been searching for this for some time!
I wonder if you tested one polystyrene and one accoustic tile in series to see how their combined work looks on REW. TI used a 40w for the ceiling tile which could give you better volume for that one
Yes, I did try that (one foam tile in series with a ceiling tile) the "problem" is the foam is about 3 times louder, thus the ceiling tile contributes VERY little. you basically can't hear the ceiling tile because the foam is so much more efficient (louder). Why work hard to make something that works poorly work better? when you already have something that works WAY better?
Thank you very much for the interesting video!
I am contemplating making some myself. I see folks in the US mostly work with the 1inch thickness XPS panels
Since i live in metric land, we only have 20mm and 30mm panels available. Would you recommend going up or down in thickness?
It might be negligable difference. Still wanted to ask!
I don't have any data on how the thickness affects performance. This material is not very strong. My panels are larger than some are building. If your making large panels (greater than 2 ft x 2 ft) I would go thicker. Maybe thinner would work better when building smaller panels.
Sorry if I missed that but did you EQ the DML panels?
The DML panels are very loud (high SPL) but the output drops off a bit at the higher frequencies, so although the highs are there and strong, they are not as loud as the mid-frequencies, thus yes, I do a very primitive EQ in the tests I did on these: which consisted of turning up the treble knob while keeping the bass know flat.
Placement- A bass boost from wall proximity of speaker panel would be convenient, as panels hanging in the middle of a room is likely untenable for most ppl. Did you test or have an opinion, thank you.
I have seen some applications where the person hung them up overhead in a cathedral ceiling area; but my tests were done with the panels rather close to the wall: one was about 2', the other at an angle to the wall, 3' away. their performance was similar. They are designed to be hung close to a wall, like next to your tv or something. some people have hung them in an open deep frame with rockwool sound absorbing insulation in the box to absorb most of the sound coming from the rear of the panel.
You have asked a very valid question.. I have started experimenting with these types of speakers after watching many how-to videos and can tell you there's a major difference in sound quality depending on proximity to the back wall.. What I can suggest is what I did, have a listener in the area where you would be listening from and another person move the speaker further away and closer while playing music. In this manner you can find the sweet spot where the interaction makes the best sound. Hope this helps!
Ciao, ottimo video è possibile utilizzare più pannelli invece di due, magari quattro pannelli o altra configurazione ? Un saluto Fabio
Each panels uses a 4 Ohm exciter. If you use two on each side wired in series 8 Ohms will result. Then you could add two more panels to each side and wire the two pairs in parallel, going back to 4 Ohms. So yes, you can add more panels. Is this clear?
Something is wrong with the sub measurement! How can it have high frequency!!! on a sub woofer!!! other than that, great job for sharing your experiences.
In the video, I misspoke: The subwoofer sweep includes the panels. It is meant to show the response of the panels and the sub working together. The sub was off for the sweeps I show for the panels.
-No credit to Tech Ingredients?- Edit: Since i read your mention of TI in the description, i withdraw my comment.
probably because they are implemented incorrectly.
@@jonmoore1614 hi, u mention that I did something incorrectly. Please share what that was so I can correct it.
Did Tech Ingredients invented these or something? They made them popular, sure, but distributed mode loudspeakers have been around for a long time.
They rock add some planar tweeters and a sub and you will love them they have solid mids lacking highs and lows.
@@VEC7ORlt Maybe I'm wrong.(?) It seemed to me that Henry de Groh built it with the same materials, same rounded corners, same two fifth/three fifth ratio like TI. So lets ask him: Sir, have you been inspired to this build by Tech Ingredients? And if so, would you mind giving them credit?
Very interesting although i can guarantee you that there is a huge amount of toxic microparticles released in the air from the vibration of those panels. That meterial was never intended to be excited in its structure. For people that have them at home it might be a good idea to wrap them in a sheet like cloth… sounds shouldn’t be affected too much.
What toxic microparticles are you talking about? These panels are 100% non toxic (extruded) polystyrene. And how would it "release" any microparticles do you reckon?!?
Please don't spread misinformation. We already have so many toxins in and around us or in our food, to worry about.
i have an idea!
Try sticking a couple ounces of wheel weights to the back of the exciter. It might lower frequency response.
i have done similar with normal speakers by adding weight to the cone & lowering the resonance frequency. That eliminated the need for a subwoofer.
I guess it's worth a try, but we also don't want to lower output in the high frequencies.
@@henrydegroh2341 Alloy wheel weights are very cheap, are easy to cut to weight, & have double-stick super-tape pre applied. I bet a single strip (~2oz) will be under $5, even free if you know a mechanic.
@@Iowa599 the back of 24 watt exciters I use have a tapped hole in them at the back, so you could attach it with a screw so it could be easily removed/changed.
@@henrydegroh2341 even better!
I bet it will have no effect on higher frequencies, because adding mass will lower the resonance frequency of the exciter, only.
that is just a theory, though...adding mass to the cone of normal speakers (coax with the tweeter removed, superqlued oil cap cone ;) ) worked to avoid a subwoofer, but I also installed a 100hz low pass crossover.