I have always been facinated by the Synergy/Unity/Multi Entry horns. I have read i think most of the threads here on DIY audio and elsewhere on the web including danleys patent and more... After the DFM groupbuy here on DIY I suddenly have three compression drivers in my hands.. So now I no longer had any excuse and have begun experimenting myself!
I also have quite a few of the small SB full rangers (SB65WBAC25-4) on hand. I have no idea how good these drivers will be as MEH mids, but we will se. I was kind of fantasysing about the Scanspeak 10F/4424G00 based on the 2*FS/QES formual they score 562 which to my understanding is pretty good?
The dream is to build three bigger 3-way horn for use as Left, Right and Center fronts in a future home cinema/listening room.
However, for now I just want to do some smaller scale tests with what I have to see if my understanding of the concept is correct as well as do some experimentation.
While I understand that the corner placement of taps in the horn reduces the taps impact on the HF performance I really would prefer an eliptical horn based on the ATH formulas from a visual standpoint. Therefore the first experiment will test if it is possible to get a decent HF performance from such a OSSE horn with taps in it.
So I started by designing a parametric horn that has replacable taps to quickly iterate differnt shapes and sizes of the taps. This is what it looks like with the midranges attached
I also have quite a few of the small SB full rangers (SB65WBAC25-4) on hand. I have no idea how good these drivers will be as MEH mids, but we will se. I was kind of fantasysing about the Scanspeak 10F/4424G00 based on the 2*FS/QES formual they score 562 which to my understanding is pretty good?
The dream is to build three bigger 3-way horn for use as Left, Right and Center fronts in a future home cinema/listening room.
However, for now I just want to do some smaller scale tests with what I have to see if my understanding of the concept is correct as well as do some experimentation.
While I understand that the corner placement of taps in the horn reduces the taps impact on the HF performance I really would prefer an eliptical horn based on the ATH formulas from a visual standpoint. Therefore the first experiment will test if it is possible to get a decent HF performance from such a OSSE horn with taps in it.
So I started by designing a parametric horn that has replacable taps to quickly iterate differnt shapes and sizes of the taps. This is what it looks like with the midranges attached
First test here shows the CD performance in the horn with blank taps as a benchmark.
Im pretty happy with that performance compared to the datasheet response. Also the measurments wasn't made under the best conditions. Not sure what causes the 1k dip to be more pronounced in my horn compared to the datasheet though?
Im pretty happy with that performance compared to the datasheet response. Also the measurments wasn't made under the best conditions. Not sure what causes the 1k dip to be more pronounced in my horn compared to the datasheet though?
Second test was the first go at a tap design. Didn't put too much thought into it but just tried to make something that look slike something I have seen before. The taps look like this
The HF performance does take quite a hit though. The midrange performance is also decent I think. There is a volumefiller under the driver effectively reducing the volume as much as possible without the membrane hitting. The taps are rather long from the driver to the horn, but again. this was for testing with what i had and not a fully optimized system.
Based on this I tried to make a crossover with a small 10" sub I use for my PC speakers. It actually sounds pretty good! It also seems my understanding of the theory is in the ball park as I was expecting an maximum crossover of 1500Hz based of the 1/4 wavelength to the CD phase plug and full wavelength of horn circumferance. It can be seen that the response drops off around my crossover off axis. this gets much worse if I cross at 1500 hz. I think this is due to the horn cirmuferance at the tap exit. but I might be wrong?
The crossovers are all acoustical LR24. I made a verification measurment and it is pretty spot on.
The HF performance does take quite a hit though. The midrange performance is also decent I think. There is a volumefiller under the driver effectively reducing the volume as much as possible without the membrane hitting. The taps are rather long from the driver to the horn, but again. this was for testing with what i had and not a fully optimized system.
Based on this I tried to make a crossover with a small 10" sub I use for my PC speakers. It actually sounds pretty good! It also seems my understanding of the theory is in the ball park as I was expecting an maximum crossover of 1500Hz based of the 1/4 wavelength to the CD phase plug and full wavelength of horn circumferance. It can be seen that the response drops off around my crossover off axis. this gets much worse if I cross at 1500 hz. I think this is due to the horn cirmuferance at the tap exit. but I might be wrong?
The crossovers are all acoustical LR24. I made a verification measurment and it is pretty spot on.
The driver voice coil may be rubbing. You would see this in the electrical impedance curve.
Otherwise the performance of the horn (without the taps) is very nice, congratulations.
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Unfortunately the Group Buy batch pieces seem to suffer from this (see the posts here).
My explanation of the FR dip is that the diaphragm is not perfectly free to move, and it's probably the region of the largest excursion.
My explanation of the FR dip is that the diaphragm is not perfectly free to move, and it's probably the region of the largest excursion.
Thanks for the link @mabat .. Sad to see that.. Even though its not the most expensive driver it still makes you feel B*** F***ed.. Do you know if anyone has taken this to tymphany or if its just the way it is now? I read the rest of that thread and it seems all or at least many of the new drivers does it?
Btw. I just realized you are the guy behind the ATH-page. You have my deepest respect and I am very gratefull that you choose to share this kind of work. You are the reason someone like me have a small change of pulling somethin glike this off. I didn't even simulate anything I just used your formulas and compared the result with your example horns. I have yet to try my luck at AKABAK or the like.
Btw. I just realized you are the guy behind the ATH-page. You have my deepest respect and I am very gratefull that you choose to share this kind of work. You are the reason someone like me have a small change of pulling somethin glike this off. I didn't even simulate anything I just used your formulas and compared the result with your example horns. I have yet to try my luck at AKABAK or the like.
There was a query for the distributor and the answer was rather disappointing but I don't have the energy right now to pursue this, there are worse things that happen in life. Unfortunately this doesn't seem as an easy fix.