The ones that say "Page 26," "building jbell's hs12," and "JBell PA Top" have all the info you should need.
Another of JBells single sheet designs has been gathering some acclaim on the SAC Forum (Software Audio Console). This design is based on the Dayton PA460-8 18" driver. I built 2 of these, ran some sweeps with REW, and asked him in PM if he'd like the data posted anywhere...he suggested this thread.
His design allowed the cabs to be deployed standing upright or laying down, mine will be permanently mounted standing upright, so I did use additional ply to close off the portion of the mouth that is blocked by the floor in that orientation.
My cabs are 3/4" birch ply, latex painted internally, and coated with Line-X externally for continuous outdoor life. I used 1/2" expanded steel as a grill, with grillcloth behind to keep rain splatter from reaching the driver easily.
Testing method:
Outdoor measurements in a park, no buildings within 100 yards
Amp output set to 28.3V at 100Hz with no load other than the meter.
DBX reference mic 1' off ground at 10 meters distance from cabinet.
Allen & Heath mixwizard used as Ref mic Preamp. REW loopback also passed through A&H
SmaartLive and REW both calibrated to match Radio Shack SPL meter at same position as reference mic
Results of 4 sweeps 20-1KHz on each cabinet averaged as single trace.
Tested: Both JBell SS18, Dayton 460-8, red/orange traces
2 Cerwin-Vega T36-750 as a 'control', blue/green traces
Frequency Response and Phase plots attached
Further data from single SS18 (Though I don't honestly know if these following plots have any validity when performed on distant measurement methods...they're still pretty)
Group Delay, Decay, Waterfall
BTW: a great sounding cab, based off of a wonderfully inexpensive driver, and one of the simplest I've ever built.
His design allowed the cabs to be deployed standing upright or laying down, mine will be permanently mounted standing upright, so I did use additional ply to close off the portion of the mouth that is blocked by the floor in that orientation.
My cabs are 3/4" birch ply, latex painted internally, and coated with Line-X externally for continuous outdoor life. I used 1/2" expanded steel as a grill, with grillcloth behind to keep rain splatter from reaching the driver easily.
Testing method:
Outdoor measurements in a park, no buildings within 100 yards
Amp output set to 28.3V at 100Hz with no load other than the meter.
DBX reference mic 1' off ground at 10 meters distance from cabinet.
Allen & Heath mixwizard used as Ref mic Preamp. REW loopback also passed through A&H
SmaartLive and REW both calibrated to match Radio Shack SPL meter at same position as reference mic
Results of 4 sweeps 20-1KHz on each cabinet averaged as single trace.
Tested: Both JBell SS18, Dayton 460-8, red/orange traces
2 Cerwin-Vega T36-750 as a 'control', blue/green traces
Frequency Response and Phase plots attached
Further data from single SS18 (Though I don't honestly know if these following plots have any validity when performed on distant measurement methods...they're still pretty)
Group Delay, Decay, Waterfall
BTW: a great sounding cab, based off of a wonderfully inexpensive driver, and one of the simplest I've ever built.
Attachments
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Each trace is a single cab.
There is no EQ, no filters, no nuttin 'cept signal, power amp, speaker, mic.
I suspect my calibration may have been off by a couple of dB as I was using a borrowed Rat shack meter (couldn't find mine) and repeated previous tests with the CVs as reference show the peak between 90 & 100 Hz to be in the 108-110 range they advertised for those cabs rather than the 104ish I got here...So I bet we can safely assume that I'm slightly under the actual performance.
There is no EQ, no filters, no nuttin 'cept signal, power amp, speaker, mic.
I suspect my calibration may have been off by a couple of dB as I was using a borrowed Rat shack meter (couldn't find mine) and repeated previous tests with the CVs as reference show the peak between 90 & 100 Hz to be in the 108-110 range they advertised for those cabs rather than the 104ish I got here...So I bet we can safely assume that I'm slightly under the actual performance.
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thanks for posting measurements -- appreciate it.
BTW -- for anyone wondering, no this is not an 18" driver stuffed in the typical ss15 cab.
The request for this cabinet design was cheapest/simplest/most output possible. (emphasis on cheapest) It's basically an up/back singlesheet TH with a dayton driver. Better drivers give more output, however I think this driver/cabinet hits the original target quite well. (hey it hangs with a T36-750 without the T36's rising response you have to eq flat)
BTW -- for anyone wondering, no this is not an 18" driver stuffed in the typical ss15 cab.
The request for this cabinet design was cheapest/simplest/most output possible. (emphasis on cheapest) It's basically an up/back singlesheet TH with a dayton driver. Better drivers give more output, however I think this driver/cabinet hits the original target quite well. (hey it hangs with a T36-750 without the T36's rising response you have to eq flat)
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For the frequent DIYAudio types -- you may notice I've been kinda MIA lately around here. Things are busy... really busy. (I've got 3 commercial video systems to install in just the next couple weeks, and that's not my day job.) There's so much to do, that the site I've been trying to get off the ground SingleSheetDesigns.com has languished and never officially seen the light of day.
I have several designs, install video's, documentation, etc... and just never got it all put in place so that the requests for designs like this could be honored in an automatic and efficient manner. I also wanted to be able to use PartsExpress wholesale, and/or other connections I have to be able to pass along some driver/plans packages to folks who want to build. Because of this, I don't want to confuse folks with more partial projects. I just don't want to compromise my name that way.
Yes, Ted -- if you want to private message respond to anyone with your google sketchup of the 'simplified' SS18 you and others on the SAC forum have built -- go ahead. However I really need to get a handle on the requests from folks on my HS12's, SS15extended, original SS15, and the new SS18 that I have built/tested but never published.
Hopefully things will slow down a bit and I can get this done for everyone -- till then, apologies to all.
I have several designs, install video's, documentation, etc... and just never got it all put in place so that the requests for designs like this could be honored in an automatic and efficient manner. I also wanted to be able to use PartsExpress wholesale, and/or other connections I have to be able to pass along some driver/plans packages to folks who want to build. Because of this, I don't want to confuse folks with more partial projects. I just don't want to compromise my name that way.
Yes, Ted -- if you want to private message respond to anyone with your google sketchup of the 'simplified' SS18 you and others on the SAC forum have built -- go ahead. However I really need to get a handle on the requests from folks on my HS12's, SS15extended, original SS15, and the new SS18 that I have built/tested but never published.
Hopefully things will slow down a bit and I can get this done for everyone -- till then, apologies to all.
JBell,
Thanks for your blessing to forward this design when requested here.
I definitely understand the 'overrun' bit, I'm eyeball deep in a distributed audio installation with 2 more on deck for when this one's done...and it's festival season, so no exaggeration I have 14 shows this week between club dates & outdoor events with mobile PA! (Cutting the grass is officially postponed)
Ramsey
Thanks for your blessing to forward this design when requested here.
I definitely understand the 'overrun' bit, I'm eyeball deep in a distributed audio installation with 2 more on deck for when this one's done...and it's festival season, so no exaggeration I have 14 shows this week between club dates & outdoor events with mobile PA! (Cutting the grass is officially postponed)
Ramsey
I've been trying to make my way through this whole thread, and there is a lot of information to digest. I'm looking at building two SS15s soon, buy will probably build the HS12s first. I see that the Dayton PA310 is a recommended driver for it, but I see that it is not recommended for the OT12, which this box was initially based on. Maybe JBell can give me some info on why it works okay in this box?
Does anyone had any pictures of finished HS12s that maybe I haven't gotten to in this thread yet? And has anyone done any real world SPL tests of an HS12 like I've seen for the SS15? I'd love to see them and see what kind of gain/efficiency this cabinet design gives.
One last thing, sorry. I'm too new to send PMs, but I saw somewhere in this thread that 4pyros is from Allentown. I'm from Wilkes-Barre, and I'd love to come hear your SS15s before I commit to building some, if thats ever an option. Thanks.
Does anyone had any pictures of finished HS12s that maybe I haven't gotten to in this thread yet? And has anyone done any real world SPL tests of an HS12 like I've seen for the SS15? I'd love to see them and see what kind of gain/efficiency this cabinet design gives.
One last thing, sorry. I'm too new to send PMs, but I saw somewhere in this thread that 4pyros is from Allentown. I'm from Wilkes-Barre, and I'd love to come hear your SS15s before I commit to building some, if thats ever an option. Thanks.
I use them for the pyro musicals at Mount Airy but sadly they only had one show on the 4th.
I will be out in rain at SAP America today, its down by King of Prussia.
I can keep you updated on our pyro musical shows if you like.