Here they are
Luca,
Here are the results of his measurements .... Not great but workable .... A lower Qts and lower voicecoil inductance (Le) would have been preferable ....
Coils in series:
Coils in Parallel:
These discrepancies run rampant across brands from what i am being told by some of the more knowledgeable car audio guys that i have met recently .... You really don't know what you are going to get until you receive it and measure it with many of these Car Audio brands ........ The problem is that some of these companies like Twisted and Skar just blindly publish the parameters given to them by their Asian suppliers, and the brand isn't bothering to verify with a simple measurement which would certainly be easy enough for them to do ........................................but why would they post the real parameters when the bogus figures look more marketable??!!? ...... Dirty
but that's not all , there is more!
Apparently the Chinese factory that produces these Twisted drivers could stand to improve their quality control .... Barnaby received a driver that was missing some glue where the outer edge of the surround is supposed to be sealed to the frame ..... He has the glue to fix it but as he says "it's the principle" ....
This company should not be asking this price for these drivers unless they can get the production problems and parameter issues fixed ..
Luca,
Here are the results of his measurements .... Not great but workable .... A lower Qts and lower voicecoil inductance (Le) would have been preferable ....
Coils in series:
Coils in Parallel:
These discrepancies run rampant across brands from what i am being told by some of the more knowledgeable car audio guys that i have met recently .... You really don't know what you are going to get until you receive it and measure it with many of these Car Audio brands ........ The problem is that some of these companies like Twisted and Skar just blindly publish the parameters given to them by their Asian suppliers, and the brand isn't bothering to verify with a simple measurement which would certainly be easy enough for them to do ........................................but why would they post the real parameters when the bogus figures look more marketable??!!? ...... Dirty
but that's not all , there is more!
Apparently the Chinese factory that produces these Twisted drivers could stand to improve their quality control .... Barnaby received a driver that was missing some glue where the outer edge of the surround is supposed to be sealed to the frame ..... He has the glue to fix it but as he says "it's the principle" ....
This company should not be asking this price for these drivers unless they can get the production problems and parameter issues fixed ..
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Thanks a lot Matthew !
But if still possible to make a "Coumpound loading 6th order" sub with a Qts of 0,57 then is possible to make this subwoofer with the inexpensive woofer that I've posted with a Qts from 0,33 to 0,54 . The only problem is probably the Bxl , but is possible that also the TSX1000 haven't a real very high Bxl......
But if still possible to make a "Coumpound loading 6th order" sub with a Qts of 0,57 then is possible to make this subwoofer with the inexpensive woofer that I've posted with a Qts from 0,33 to 0,54 . The only problem is probably the Bxl , but is possible that also the TSX1000 haven't a real very high Bxl......
Good news
Hey guys , I have good news!
The Dayton RSS315HO-4 12" subwoofer has published parameters that work well in a Super Planar 8th
It is my understanding that Dayton's published parameters are generally accurate with the exception of a few of their heavy duty PA drivers (there was a 15" and an 18" that had some issues from what i have read).. .
Has anyone yet measured this driver to verify it's parameters?!?!
Dayton Audio RSS315HO-4 12" Reference HO Subwoofer 4 Ohm
Based on the published figures i can put two of the Dayton HO 12 (svc) drivers into a 420 liter Super Planar 8th order cabinet tuned to 34hz and get performance that is very similar to a decent 18" PA driver from 35hz to 100hz .... F3 is 35hz , and the Group Delay is very very low ....
This cabinet would have the same internal volume as the Cerwin Vega L36 (in all of it's many incarnations and clones) but the performance is far better with this Super Planar 8th design and the Dayton 12s ..
Luca, are you able to purchase the Dayton HO 12" (single voice coil 4 ohm) drivers in Italy ?? If so then this is the driver you have been looking for
assuming that Dayton's published parameters are correct on this model ..
I plan on posting some graphs and inputs here in the next few days
Hey guys , I have good news!
The Dayton RSS315HO-4 12" subwoofer has published parameters that work well in a Super Planar 8th
It is my understanding that Dayton's published parameters are generally accurate with the exception of a few of their heavy duty PA drivers (there was a 15" and an 18" that had some issues from what i have read).. .
Has anyone yet measured this driver to verify it's parameters?!?!
Dayton Audio RSS315HO-4 12" Reference HO Subwoofer 4 Ohm
Based on the published figures i can put two of the Dayton HO 12 (svc) drivers into a 420 liter Super Planar 8th order cabinet tuned to 34hz and get performance that is very similar to a decent 18" PA driver from 35hz to 100hz .... F3 is 35hz , and the Group Delay is very very low ....
This cabinet would have the same internal volume as the Cerwin Vega L36 (in all of it's many incarnations and clones) but the performance is far better with this Super Planar 8th design and the Dayton 12s ..
Luca, are you able to purchase the Dayton HO 12" (single voice coil 4 ohm) drivers in Italy ?? If so then this is the driver you have been looking for
assuming that Dayton's published parameters are correct on this model ..I plan on posting some graphs and inputs here in the next few days
The Dayton is available in Germany:
Dayton-Lautsprecher RSS315HO-4
It's price is rather forbidding, compared to the US price.
Dayton-Lautsprecher RSS315HO-4
It's price is rather forbidding, compared to the US price.
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Luca,
No problem on providing the Twisted data, and indeed the Twisted 12 has a Qts of .576 but Qts doesn't tell us the whole story .... Developing a Large amount of motor force is key with these high order designs ... You have to look at the relationship between the BL and Re figures , and also the ratio of the Le to Re in order to come up with a number that you can use to compare the motor force between drivers with different impedances ....
A good place to start is by multiplying the BL by the BL and then dividing by the Re .... This gives you a basic motor force figure that you can use to compare drivers ..... Note that when the Le is high in relation to the Re we lose a considerable amount of motor force (Just A Guy and David McBean have discussed that formula here)....
To give you an example:
MOTOR FORCE: (BL^2/Re adjusted for Lossy Inductance)
Twisted TSX1000 12" D4 = 45.6 (it's high Le:Re ratio really hurts it)
Dayton RSS315HO-4 12"= 77
As you can see the Dayton HO 12 has a much stronger motor, so that is what allows it to work in a considerably smaller Super Planar 8th cabinet (420 liter versus 600 liter , for dual drivers and tuned to around 35hz).
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I built this simple tapped pipe design as a very cheap home theater sub for a friend, but the Fane 10 inch driver did not last very long.
GAS ALPHA 10D2 | GAS | Billjud | Brl.se
I needed a strong heavy duty driver with a quite low Qts and a strong cone that could take the quite large warping pressures inside the tapped pipe without complaining. The GAS Alpha 10 has a published Qts of 0,30 and I am inclined to believe the published Qts even though it is a cheap car audio driver.
The green line is measured outdoors at 1 meter and the red line is at 3 meters. Both lines are 4 sweeps each to leave out background noice.
This is my best guesstimate working back and forth between the published specs, the measured performance in the tapped pipe and my previous experience of different drivers in this tapped pipe.
It is not very precise. I believe it has a little less Bl then this. I am using lossy Le in this sim.
I don't think shipping to Germany from Sweden is very expensive.
898 Swedish kronor is about 100 US dollars.
A picture I stole from their homepage.
It is a quite robust driver. We pushed one channel of my QSC RMX 1450 (500 watts) to constant clipping for 30 minutes and the bass was tremendous even though we were outdoors. We could not provoke any audible distortion from the driver despite very bass heavy EDM and no high pass filter.
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No. The driver is glued into the box and it is already delivered to the owner.
I wish I had measured the driver, since it eases the design phase a lot.
Me, the current owner, my son and his friend are all very impressed by the performance of this cheap home theater sub.
We are planing to buy another one, but we have several projects we need to complete first.
I am going to measure the next one, but it might take a while.
Cheers,
Johannes
I wish I had measured the driver, since it eases the design phase a lot.
Me, the current owner, my son and his friend are all very impressed by the performance of this cheap home theater sub.
We are planing to buy another one, but we have several projects we need to complete first.
I am going to measure the next one, but it might take a while.
Cheers,
Johannes
We increased the power slowly while checking the cone displacement with a finger on the cone. We could never feel any excessive cone excursion. I guess it was regularly moving plus minus 5 - 8 mm or so.
We did sense a scent of hot voice coil after a while.
There was one single mm of clearance behind the magnet in the tapped pipe. This is not optimal, since it blocks of the air flow through the pole piece. I did not want to build a new box. I knew it was a tight fit, but I hope it will survive. It is a home theater sub, so it should never have to endure prolonged periods of intense use. It is usually most explosions and collapsing buildings and stuff. The Gas Alpha 10D2 seems like a very rugged driver.
The baffle is 36 mm thick - two layers of 18 mm plywood. This is a way to get a very robust and stiff mounting of the driver, and a way to get more clearance behind the driver.
If I have to build another box, it will be tuned a few Hz deeper and I will increase the distance behind the driver to ease the airflow and cooling of the driver.
I don't believe he will regularly drive my QSC to clip in his basement though. Its a quite brutal experience, and his whole house complains as loudly as his wife...
I have contacted BRL who owns the GAS brand and asked for more data. They promised to get back to me. I hope they can provide complete and reliable TS-data for their drivers.
I told them that there is some interest in their drivers in mainland Europe and probably even the states, but we need reliable data to design our basshorns, tapped pipes, tapped horns, series-tuned 6th order quarter wave resonators etc...
I am very impressed by the performance of this cheap driver. It compares quite favorably (considering the price) to my B&C 12PS100 in clean punchy bass outdoors, even though my ROAR is much more efficient and thus much louder.
It was very clean and very low distortion. No mechanical noises from the driver at any level up to clip.
Cheers,
Johannes
I told them that there is some interest in their drivers in mainland Europe and probably even the states, but we need reliable data to design our basshorns, tapped pipes, tapped horns, series-tuned 6th order quarter wave resonators etc...
I am very impressed by the performance of this cheap driver. It compares quite favorably (considering the price) to my B&C 12PS100 in clean punchy bass outdoors, even though my ROAR is much more efficient and thus much louder.
It was very clean and very low distortion. No mechanical noises from the driver at any level up to clip.
Cheers,
Johannes