Hey everyone!
So after some field experience with my LAB12 in a ported box (let me tell you what doesn't make for a loud bottom end) I've finally decided to build the PAL12 TH as it's response looks noticeably nicer than the Tuba45 the driver was originally meant for (not digging that huge 10dB rise to 100Hz)
Sorry if this post looks similar to my previous one about the aforementioned ported 12, I promise I'm going somewhere useful!
I'm super interested in this project;
Q15 Compact 15" Bass bin
And here in 'Murica the BMS driver might be tricky to come around but THIS ISN'T!
PRV Audio 15SW2000 15" High Power Pro Audio Subwoofer 8 Ohms
(Slightly baffled as to why the unsatisfied buyer had used a Subwoofer as a midrange)
Those Q15 subs had gotten some great reviews and the PRV driver while only 1dB down on sensitivity has it beat on several specs like Xmax and Pe which to a noob like me, seem to be all that matters in a BR! (I'm trying to learn!) However, will this PRV driver's .46 Qts mess up the response compared to the BMS's .32?
So, the question is, can I place this PRV Audio driver in the Q15 box and use the B6 assisted alignment with similar results? the designer claims strong bass down to ~40 Hz with fairly good SPL. (potential iron law fault)
This would be for those occasions where 1 corner loaded sub and 1 top is all I need for house parties and such. I do love my Bass-Happy house music (EDM if you will) and TRAP, but with a PAL12 TH on the horizon I can wait for the full effect!
So any tips would be wonderfully appreciated. Would I be better off with a build like this?
http://www.diyaudio.com/forums/subwoofers/219923-ultra-compact-ported-15-dayton-ref-ho.html
I thought I could be sneaky and pop this driver in a proven box and be happy!
P.S. Someone will have to explain how this B6 alignment works (something about .707 of a normal F3 for this size box?) and how it is achieved on my DriveRack...
THANK YOU!
So after some field experience with my LAB12 in a ported box (let me tell you what doesn't make for a loud bottom end) I've finally decided to build the PAL12 TH as it's response looks noticeably nicer than the Tuba45 the driver was originally meant for (not digging that huge 10dB rise to 100Hz)
Sorry if this post looks similar to my previous one about the aforementioned ported 12, I promise I'm going somewhere useful!
I'm super interested in this project;
Q15 Compact 15" Bass bin
And here in 'Murica the BMS driver might be tricky to come around but THIS ISN'T!
PRV Audio 15SW2000 15" High Power Pro Audio Subwoofer 8 Ohms
(Slightly baffled as to why the unsatisfied buyer had used a Subwoofer as a midrange)
Those Q15 subs had gotten some great reviews and the PRV driver while only 1dB down on sensitivity has it beat on several specs like Xmax and Pe which to a noob like me, seem to be all that matters in a BR! (I'm trying to learn!) However, will this PRV driver's .46 Qts mess up the response compared to the BMS's .32?
So, the question is, can I place this PRV Audio driver in the Q15 box and use the B6 assisted alignment with similar results? the designer claims strong bass down to ~40 Hz with fairly good SPL. (potential iron law fault)
This would be for those occasions where 1 corner loaded sub and 1 top is all I need for house parties and such. I do love my Bass-Happy house music (EDM if you will) and TRAP, but with a PAL12 TH on the horizon I can wait for the full effect!
So any tips would be wonderfully appreciated. Would I be better off with a build like this?
http://www.diyaudio.com/forums/subwoofers/219923-ultra-compact-ported-15-dayton-ref-ho.html
I thought I could be sneaky and pop this driver in a proven box and be happy!
P.S. Someone will have to explain how this B6 alignment works (something about .707 of a normal F3 for this size box?) and how it is achieved on my DriveRack...
THANK YOU!
Is the Dayton a better choice due to the lower Qts? I tried simming it in WinISD and I guess none of these small boxes are going to have flattering curves without EQ. How does that B6 EQ not just kill your headroom?
This quote is from the Q15 thread:
"The response does tail off quite quickly below 40Hz as could be expected given the enclosure size and the processor settings. High pass at 41Hz Butterworth 12dB/oct with 8.7dB Parametric EQ at 41Hz (B6 alignment). Excursion seems to be well controlled and I've not had any issues running them one either side of a 1000W/ch into 8ohms amp."
This quote is from the Q15 thread:
"The response does tail off quite quickly below 40Hz as could be expected given the enclosure size and the processor settings. High pass at 41Hz Butterworth 12dB/oct with 8.7dB Parametric EQ at 41Hz (B6 alignment). Excursion seems to be well controlled and I've not had any issues running them one either side of a 1000W/ch into 8ohms amp."
I have been aging around on WinISD lately with this idea. With the additional 20-40 liters of box volume and Fb at 40Hz, It looks to have very nice output; up to 10dB more than my LAB12 reflex at 100Hz (where I cross with my OTop) but only 3-4dB on the low end (35-40Hz)
Back to the B6 alignment questions, what kind of negative impacts are there with boosting EQ at excursion minima? I'm not looking for flat to 35 performance from a small portable party sub, but a boost at 40Hz seems like it would be perfect for a smaller box.
Sent from my iPhone using Tapatalk
Are these the same B&C's that the Dayton's look like they copied? [emoji57] I can sim in WinISD but how do you like the low end performance of them? Have you ever used EQ for a boost?
Sent from my iPhone using Tapatalk
Last edited:
In my opinion Lab 12 are strictly horn drivers for PA use. The cone is too weighty for efficient bass reflex enclosures - it's built more like a car subwoofer than a bass reflex PA subwoofer, thus it will drink power and not give much sound in return. On top of that it's optimised for lower tuning e.g. 25-30Hz in home cinema.
Excursion minima are usually impedance minima. Too much power around there could heat things up.
As for Tuba 45 boundary loading should bring the lower bass up on par with the upper bass. Look at absolute numbers though too (although the Tuba 30 and 24 seem to have sub-par efficiencies in the bottom of the range, the horn looks designed for V-Plating due to the sudden flare that allows a long horn in a small box) the Tuba 45 seems to be more efficient at the lower bass judging by the graph and it has a bigger effective mouth size built into the cab.
I've been playing around with the T/S parameters of the B&C 18SW115 in a 6th order bandpass and got a theoretical 133dB from 40/45-100Hz with 110V (2Pi.
Chamber 1 is 135L + 500cm^2 * 45cm port (total 157.5L) for ~41 Hz tuning. Chamber 2 is 50L + 500cm^2 * 28cm port (Total 64L) for ~82Hz tuning. Sensitivity is between 100-102dB from 42-104Hz. (This is about 4dB more than the Bass reflex). I wonder how this would compare to sine143's mini tapped horn with the same driver.
Precision devices 15BR40 seems to sim equally well, although with less maximum power output.
Excursion minima are usually impedance minima. Too much power around there could heat things up.
As for Tuba 45 boundary loading should bring the lower bass up on par with the upper bass. Look at absolute numbers though too (although the Tuba 30 and 24 seem to have sub-par efficiencies in the bottom of the range, the horn looks designed for V-Plating due to the sudden flare that allows a long horn in a small box) the Tuba 45 seems to be more efficient at the lower bass judging by the graph and it has a bigger effective mouth size built into the cab.
I've been playing around with the T/S parameters of the B&C 18SW115 in a 6th order bandpass and got a theoretical 133dB from 40/45-100Hz with 110V (2Pi.
Chamber 1 is 135L + 500cm^2 * 45cm port (total 157.5L) for ~41 Hz tuning. Chamber 2 is 50L + 500cm^2 * 28cm port (Total 64L) for ~82Hz tuning. Sensitivity is between 100-102dB from 42-104Hz. (This is about 4dB more than the Bass reflex). I wonder how this would compare to sine143's mini tapped horn with the same driver.
Precision devices 15BR40 seems to sim equally well, although with less maximum power output.
Last edited:
I've got the B&C 15TBW100-4. They are much more sensitive in kick frequencies than the Dayton HO, and the low bass rolls off much quicker. Such that I lowered the highpass, and adjusted the lowpass to cut the kick. PEQ sometimes, but I start with the high and low pass. I use the DSP in my amp and just tune by ear (I have a pretty good ear).
I would rather still have the daytons, but they couldn't take the heat.
Last edited:
Hell yeah to that, the according to the sim, the box helps bump the low bass to a better level than the rest of the inefficient passband. Then again, I wasnt hoping for much, just needed something to run with my top on a Halloween party!
Now that I plan on building this PAL12 however, its time to build a proper BassReflex.
I was first intrigued by the possibility boosting EQ at excursion minima, but after reading Art Welter's replies to rated power and sine waves (I do love me some EDM and 808-laden trap/hip-hop), it really seems like I'm going to barbecue a a driver if I'm trying to play 40Hz sine waves while boosting that frequency despite the 1000Watt Pe. Can anyone validate/refute that assumption?
Again, I'm not looking to get PA levels out of a single 15 BR, I just know I can go louder than a LAB12 in a similarly small package (running 60 Liters now) and REASONABLY as low (would probably settle for a 40Hz F3)
I have a couple BFM subs and often in room it flattens out (corner), I have the T60 which is reasonably close to the t45 response curve. If the high sensitivity in the upper range looks like a bad thing you're not fond of using your EQ... it saves you power up high and all you need is 1 wide parametric filter -3dB or so at 80 Hz to get it flat, assuming you don't low pass at 80 (I lp everything at 80). 1 T45 will be silly loud, but the TH will go louder with a cutoff tradeoff, good luck! At 35 Hz the t45 is still pretty sensitive.
Last edited:
It certainly is sensitive at 35Hz! but after looking around on this glorious site (and having it recommended to me by its designer) the PAL12 looks to be a monster for its size. It actually occupies less volume than an 18" T45 and according to hornresp should be within 1dB sensitivity at 35Hz. I already bought the LAB12 in anticipation of building the T45 and this PAL12 looks VASTLY easier to build with a flatter response. So I can't wait to whip one up!
Of course now I'll have to find a new sub to build once the LAB12 is relieved of its reflex duty! (for good reason)
I just don't have to budget to pick out a FaitalPRO or B&C just yet =( But this Dayton looks like too good of a deal to pass up If I can come up with a box for it.
Anything I build will be placed in a corner; it seems silly to pass up that free output if I don't have to.
I've been reading Don Keele's AES paper on the B6 assisted alignment lately
http://www.xlrtechs.com/dbkeele.com/PDF/Keele%20(1975-07%20AES%20Published)%20-%20New%20Set%20of%20VB%20Alignments.pdf
It still seems like a valid method of achieving these output and extension goals I'm looking for (remember I'm just trying to beat a LAB12 and maintain a high 30's F3!!)
Here is an alternative to the PAL12 that achieves more 35-100 Hz output in 8.5 cu.ft versus the 9.7 that the PAL12 takes up with equal/lower cost. I say lower because I was able to buy 2 SWS12d4 drivers (500 watts each, 15 mm xmax) for 65 a piece which totals 130 (less than 165 for a lab 12).
It's also a tapped horn, it's my own design so let me know if you are interested in the model. Downside(s) - casters aren't in the original design but can be added and drivers are a pain to install.
More power handling at 1000 watts displacement limited with 30Hz HP 4th order or more. Impedance max and excursion minima around 38-42 Hz (perfect imo)
Attachments
Tests have gone well, upper bass is about 4 dB less than the 40 Hz region (as expected). It struggles a little with 30 Hz material but playing within it's passband it can get very loud without stressing. Intended to be HP at 32-35 I can't really knock it for not playing 30 loud
. Haven't done outdoor tests so can't comment on that front. One thing is if you have 5x5 material it's easier to make the sides the full 50 inches and then put the end pieces sandwhiched, my version requires 1/16 inch accuracy because I had 4x8's to work with and matching side length is tricky.
Hmm, well since I was fully expecting a 35Hz high pass with the tuba and since the music I play doesn't NEED that extension (hip hop and TRAP max at mid to low 30's, EDM more like 40's and no crazy dubstep) I'm happy to stay strong anywhere Into the 30's.
Size is always the biggest concern and until I get a new hatchback I'm limited to my SAAB's backseat. I can definitely fit 48" long, does that mess up the sim?
Sent from my iPhone using Tapatalk
Size is always the biggest concern and until I get a new hatchback I'm limited to my SAAB's backseat. I can definitely fit 48" long, does that mess up the sim?
Sent from my iPhone using Tapatalk
If you make it 48 long that won't be much difference from 49.5 (what I built). You'd lose 1 hz cutoff. So 36 Hz would be f3 rather than 35.
One thing to keep in mind is I would put both drivers facing inwards because I have a hunch that it chokes it at high output to have push pull (either variation). Only noticeable with 30 Hz content so may not be an issue.
Last edited:
I did see the last post on your thread pertaining to that. I'll have to check back for results if you go about testing that theory!
Pay me 2 beers and I'll get around to swapping driver orientation
haha, anyways it doesn't really effect me because I have my T60 covering the extra low range anyways and I'm only really using the 2x12 for "fill" in my tiny 10x13 room.- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.