Measuring is knowing as we say here in the Netherlands. Moving these subs around will be quite te task. Thankfully there a transporttrolly's. Eq will be done when I've got everything in order. There's not much placement options though considering the size of the thing. Basically two, front or back because of my room layout.
That was my concern also. Much more acoutic power in the same space with two woofers. Singles it is.
By change I came across a potentially nice deal on some second hand jbl cs1214 woofers that are as good as new for 30 euro a piece. Did some sims and they turn out to be better in terms of max spl, more even freq response and group delay. What do you guys think?
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The JBL CS1214 venting does not appear to make wind noise, so at least that is good.
Looks like it should work in the TH, though it sounds like the distortion may be a lot higher than other speakers with similar TS parameters:
https://www.beisammen.de/index.php?thread/120161-test-jbl-cs1214/
I have not signed up on that site so can't read the distortion curves, but if distortion shows up at half Xmax free air, could be a problem in the TH loading.
Looks like it should work in the TH, though it sounds like the distortion may be a lot higher than other speakers with similar TS parameters:
https://www.beisammen.de/index.php?thread/120161-test-jbl-cs1214/
I have not signed up on that site so can't read the distortion curves, but if distortion shows up at half Xmax free air, could be a problem in the TH loading.
@Magician1981
This is the woofer in my neighbor's Honda, though had forgotten it was a ~17 Hz T-TQWT (inverse tapered TH) and as of yesterday still pounding out Tex Mex hip hop? Regardless, thoroughly obnoxious resonant noise to my Classical/Big Band/Country/DooWop/R&R upbringings.
This is the woofer in my neighbor's Honda, though had forgotten it was a ~17 Hz T-TQWT (inverse tapered TH) and as of yesterday still pounding out Tex Mex hip hop? Regardless, thoroughly obnoxious resonant noise to my Classical/Big Band/Country/DooWop/R&R upbringings.
First of all let me thank everyone who has contributed to this project and helping me out with getting this th build of the ground using different drivers.
After thinking things through I've came to the conclusion that a single large th sub would be preferable. One that goes deeper, has higher spl and smaller overall footprint. After searching various forums I landed on a th design called lilwrecker. It's a single 15'' tuned around +-17hz, but goes as deep as 15hz (room acoustics aside). For those who are interested please have a look at the attached sims. Driver is a kicker cvr124 and costs about 230 Euro's. My amp delivers about 250W 8 ohms in bridge.
Kind regards.
After thinking things through I've came to the conclusion that a single large th sub would be preferable. One that goes deeper, has higher spl and smaller overall footprint. After searching various forums I landed on a th design called lilwrecker. It's a single 15'' tuned around +-17hz, but goes as deep as 15hz (room acoustics aside). For those who are interested please have a look at the attached sims. Driver is a kicker cvr124 and costs about 230 Euro's. My amp delivers about 250W 8 ohms in bridge.
Kind regards.
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@Magician1981
This is the woofer in my neighbor's Honda, though had forgotten it was a ~17 Hz T-TQWT (inverse tapered TH) and as of yesterday still pounding out Tex Mex hip hop? Regardless, thoroughly obnoxious resonant noise to my Classical/Big Band/Country/DooWop/R&R upbringings.
nice! whats 'thoroughly obnoxious resonant noise'? the sound of that design in the car by chance?
My bad it's cvr154. In the comment section of hornresp is the correct driver. Regarding ts parameters, those are provided by the manufacturer. The designer of this sub has verified that the cvx154 works well with this design. Someone on that forum used the cvr154 and confirmed that it works also. He included some spl measurements.
Regarding vas that comes very close to the cvx. Q's are somewhat off.
Regarding vas that comes very close to the cvx. Q's are somewhat off.
Its typical ~ 'one note' booming of the trunk from the outside, i.e. a boom-boom car. Inside it's even more obnoxious with some action movies and associated hip hop? I was in and out pretty quick! Regardless, they're happy and the $40? JBL on sale some years ago has so far been quite the bargain.
Not saying it won't work, just that the published specs aren't even in the same 'ballpark', so please post what all you have as these are cheap mobile audio speakers, which don't include big a$$ motor/low Qts bass horn driver specs. The 'giveaway' is the 27.57 BL, 8.0 Le specs.
Also, they don't post driver 'Sd' specs or even its effective piston diameter, so how did they arrive at it as it's size is even bigger than my Altec's long time record setting 12.75" eff. dia..
Sd is at the bottom of the page:
Sd 839.82 cm²
Good point regarding vc diameter. Could not find it anywhere.
What do you mean with all that I have? All the drivers that are available here?
The problem is that there aren't many suitable drivers available here as for example the usa. On parts expresse there are a ton listed for decent prices. Those ones, if available in the netherland, costs about 40% more making it not a real good deal. So consessions have to be made.
What would your preferable ts par look like?
Sd 839.82 cm²
Good point regarding vc diameter. Could not find it anywhere.
What do you mean with all that I have? All the drivers that are available here?
The problem is that there aren't many suitable drivers available here as for example the usa. On parts expresse there are a ton listed for decent prices. Those ones, if available in the netherland, costs about 40% more making it not a real good deal. So consessions have to be made.
What would your preferable ts par look like?
Looking into T-TQWT on this forum. Found a very long thread. Are there any plans listed somewhere of the final version? Could someone please tell me if distortion is the same with other types of TH in theory?
The tapered down to exit version has a large bandwidth between Fb and the rest of the 1/4 wave resonances.
The tapered open to exit has a very limited bandwidth as those resonances are all bunched together at Fb- ~ 3 Fb.
The tapered open to exit has a very limited bandwidth as those resonances are all bunched together at Fb- ~ 3 Fb.
Interesting. Are the plans and cutlist still available? Haven't found them on this forum yet. Would be very appreciated!
There are many T-TQWT designs & plans on this forum, here's one:
https://www.diyaudio.com/community/threads/t-tqwt-subwoofer.232767/
Given the same voltage input, a T-TQWT has similar SPL output to a BR of the same volume, a TH has greater SPL over a more limited usable bandwidth.
The TH's higher compression ratio puts more stress on the cone, contributing to more distortion per given voltage/excursion, but similar distortion for a given SPL.