A high quality dual 18 ported sub with a pair of columns (20 3" drivers each) would do just fine but. Moving the sub would suck.
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Sealed subs like bag end infra
- Thread starter kringle77
- Start date
IMHO a high quality dual 18 ported sub is way more than you need for twenty 3" drivers; especially if you are running the 3s down to 160hz.
Interesting. That's starting to sound like PJB kinds of stuff. I had the 16B and 8T for a while. Not portable but lightning quick transients. It also makes me think of the K-Array PA gear. It sounds great and is very expensive. I'd like to see pictures when you get it. Here's a snap of my gig yesterday for better size context.
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Have you calculated max SPL at 160hz?
Here's what I am basing my curiosity on. I mixed daily on the original Bose L1 columns with four B1 bass module for about two months and SPL was a huge limiting factor. I believe each column used 24 2.25" drivers. Max SPL is listed as 115 dB SPL (121 dB SPL peak). This was with 250W for the highs and 250W for the lows. I believe the crossover was a little higher than 160Hz, but the drivers are a bit smaller, so obviously not an apples to apples comparison with your speakers, but enough to make me wonder how much SPL you really need. IMHO a big dual 18" sub is probably serious overkill.
For comparison the Max Peak SPL for a single JBL VRX918SP is 126dB. The spec for the unpowered version (VRX918S) is 130dB.
Well, Im thinking about going direct with my bass. Normally I use 2 bag end sd15 cabs indoors, 3 of them outdoors. So, the system has to cover that, the kick drum and, samples. I do prefer to have plenty of clean headroom. Basically, we are a cover band that does everything from george jones, metallica, lady gaga and green day, but does it with the attitude of motley crue. So, there has to be some authority and thump.
Pretty sure a single JBL VRX918SP will trounce three Bag End S15s below 100Hz. I used to biamp a GK 800RB into an S15 and a RAMSA WSA200. The rig was super articulate, but had zero fat.
Okay I just Googled the PZtronics VLA-2 you referenced earlier in the thread (see attached). They are rated for 1000W from 60-18kHz, but the Max SPL is listed as 100dB at 100'. They won't behave as a line source over that entire frequency, but for mid band frequencies assume they well; therefore SPL increase 3dB for each halving of distance. At 3.125' the calculated change in SPL will be +15dB, so 115dB. I would assume the rated figure is peak, so drop 6dB and you get 109dB continuous. That's significantly less than the old Bose L1 Model 1 I mentioned. I believe the explanation for this is the VLA-2 columns go much lower than the Bose columns, so the drivers are less efficient.
The Bose L1 Model 1 used smaller drivers and they still got pretty beamy in the end. I put the Bose in front of the band and had to place them much closer to the center than normal due to the narrowing of the horizontal dispersion pattern in the high frequencies. If I placed them at the edge of the band, the acoustic image in the center collapsed.
Also, I felt that cymbals sounded a bit weird. I believe the reason is the frequencies produced by cymbals are so high that you start getting some phasing between the drivers. I don't remember the formula, but the diameter of the drivers determines the high frequency cutoff in which the array stops behaving as a line source. The bigger 3" drivers in the VLA-2s will push the frequency in which this occurs lower. I believe the modern Bose column arrays splay every other driver left or right to get the acoustic centers closer and broaden the horizontal dispersion. Some other column speakers like the Turbo Sound IP2000 just cross over the highest frequencies to a horn that is mounted on top of the array.
The Bose L1 Model 1 used smaller drivers and they still got pretty beamy in the end. I put the Bose in front of the band and had to place them much closer to the center than normal due to the narrowing of the horizontal dispersion pattern in the high frequencies. If I placed them at the edge of the band, the acoustic image in the center collapsed.
Also, I felt that cymbals sounded a bit weird. I believe the reason is the frequencies produced by cymbals are so high that you start getting some phasing between the drivers. I don't remember the formula, but the diameter of the drivers determines the high frequency cutoff in which the array stops behaving as a line source. The bigger 3" drivers in the VLA-2s will push the frequency in which this occurs lower. I believe the modern Bose column arrays splay every other driver left or right to get the acoustic centers closer and broaden the horizontal dispersion. Some other column speakers like the Turbo Sound IP2000 just cross over the highest frequencies to a horn that is mounted on top of the array.
I find this very intriguing. I’m in a situation now where the PA has no sub support, just “speakers on a pole” with maybe 12-15” woofs. I think getting myself a more substantial rig would be beneficial.
Just curious, what crossover frequency did you use between the SL 112 and BE?
Regards,
Wayne A. Pflughaupt
Pedulla Club #45 Unique Arrangements of Hymns, P&W Standards, and Original Tunes
Administrator, Tobias Club #133
Administrator, Fretless Club #943
Big Cabs Club #23
My Basses
Pedulla Club #45
Tobias Club #133
Wasnex, do you think a parametric equalizer could emulate the effect of the Bag End processor?
Regards,
Wayne A. Pflughaupt
Pedulla Club #45 Unique Arrangements of Hymns, P&W Standards, and Original Tunes
Administrator, Tobias Club #133
Administrator, Fretless Club #943
Big Cabs Club #23
My Basses
Pedulla Club #45
Tobias Club #133
I believe so. Years ago I used a parametric to extend the low end of my Ampeg 810 to 40Hz.
What you don't get without the processor is the Concealment (limiting of the extreme lows). Also the document I linked in post #18 suggests the phase response will be different with a dual integrator than you would expect with EQ based compensation.
you mean to play bass through?
that works but only to a point, which is where you're on a par with the drum kit, specifically the kick drum. with no subs that isn't gonna be very loud.
as do we all
sounds like you just need to get a good PA system with good subs, it's not more complicated than that.
(it's definitely not gonna be cost effective to try and build your own, when modern PA stuff integrates the power and DSP right into the boxes you're not going to to do better than QSC or RCF or whoever.)
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even better, if you're a band trying to do louder more high energy shows, just get a guy who already has all that stuff and let him do all of it. much less stress for the band and it'll sound more pro.
I actually have plenty of good gear, the trick is getting the most performance out of the least gear. Using column arrays helps to achieve this. Also, my group tends to get a better live sound than the other locals so, there is nobody to hand the reins to. In my area, most band decisions are made out of necessity rather than want. So, I have a 3 piece band that covers everything, everyone sings and I run the sound. Yeah, its alot of work.
Sorry for the long delay. The BE has its own crossover. I use the TH750 amp and just rolled all the bass off. Its centered at 40hz but at zero sounds quite thin.
To put
My 2 cents is that using an eq to make a cabinet do something it is not designed for (like go real low) does not work because eq is only one part of the process. These days it seems like high-end (PA) gear that goes into the high 20's is integrated with specific DSP settings one way or another. Subs that go low and loud are expensive. For example, price out a Meyer single 18" self powered. It's a head scratcher until you year it - then it all makes sense. 750-LFC And there are a variety of other high-end, self-powered subs in that price range. I've recently used JBL's G28's although in fairness its a dual 18" - the speaker cab alone with no amp or DSP is over $8K. Invalid Link Removed
The BE actually "sounds" like one of the very expensive subs at about 25% of the price. Not as loud but enough for stage. So in that regard the BE fits a unique place.
These subs have some juice too and they only weigh about 60lbs.
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My 2 cents is that using an eq to make a cabinet do something it is not designed for (like go real low) does not work because eq is only one part of the process. These days it seems like high-end (PA) gear that goes into the high 20's is integrated with specific DSP settings one way or another. Subs that go low and loud are expensive. For example, price out a Meyer single 18" self powered. It's a head scratcher until you year it - then it all makes sense. 750-LFC And there are a variety of other high-end, self-powered subs in that price range. I've recently used JBL's G28's although in fairness its a dual 18" - the speaker cab alone with no amp or DSP is over $8K. Invalid Link Removed
The BE actually "sounds" like one of the very expensive subs at about 25% of the price. Not as loud but enough for stage. So in that regard the BE fits a unique place.
These subs have some juice too and they only weigh about 60lbs.
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I don't think there is any problem whatsoever using an Ampeg 810 or other sealed cab in this way as long as you take care to not exceed the driver's power rating or excursion limits. This approach doesn't really work for vented cabs, because if you push the response below the port tuning, the driver unloads and hit's it's excursion limits at low power and without producing much sound.
I have worked with an SVT and 810 EQ'ed to be relatively flat to 40Hz and it worked fine and got plenty loud for the music I was playing. The SVT was crossed over at 200Hz to a Fender Twin with JBL E120s.
I have also worked with four S18C Compacts with the ELF1 processor and fed by two QSC PL1.8, so 400W per cab.
I never compared the two directly. They both sounded nice. I used the SVT as part of a bass rig and I was playing 4-string. Keep in mind bass does not put out a strong fundamental, so this was probably part of the reason the rig worked. I never ran out of headroom with the SVT, so the missing parts of the process (Concealment and Limiting) was not a factor. Additionally the 810 can easily handle all of the SVT's power even at 40hz, so again, the Concealment and Limiting is not relevant. The Concealment is really the only missing part of the process that is a bit trick...very easy to insert a limiter in the signal chain.
The S18Cs were part of a portable PA. It was very easy to push the four S18C Compacts to the point where the Concealment became active and with certain types of program material it was very obvious even at relatively low volume. But for general pop music they did pretty well for such small subs. The system had a pair a TA12s and TA12JRs for mains which I believe were drive by a pair of QSC PL1.6s. The subs were definitely the limiting factor. Basically you ran the SPL up till the Concealment started thinning the bass out too much.
It's been a long time since I ran these subs, I am pretty sure I found it advantageous to limit the low end extension to about 40hz in our application instead of running them all the way down to 8hz. They were fairly expensive (especially in Europe) and if the basis for purchase was done on a cost/performance analysis alone there were much better choices. I am pretty sure a single properly powered JBL VRX918S would stomp all four of the S18C Compacts from 35hz up as far as SPL. But their small size was a huge factor in my purchase decision.
For the record the Bag End system replace an Apogee system consisting of two AE10s, two AE5s, and four AE3s properly powered and processed. Performance wise the Apogee system was significantly louder and sounded way better, but it was also big and heavy.
The Bag End system allowed me to put a 5-piece rock band in this type of plane with a full PA.
True for sure it could be done. I've cooked a few small speakers without really noticing it was happening. Especially those Euphonic Audio VL 110's which I loved. Referencing your example, an Ampeg 810 weighs 165 pounds and is a refrigerator. No doubt you could coax more lows out. But finding out if you're pushing excursion limits could be expensive. The first harmonic above the fundamental is MASSIVE! It still does not feel like the actual fundamental. The self-powered INFRA BE Single 18" is 67 pounds and is relatively small. I know you were not referring to weight or size but that is a factor for my "smallish" gigs where there aren't "pro" subs that go low. I replaced my 2nd Aguilar SL112 with the BE 18 and it was a significant improvement in "resolution" at the low end. I like your PA transportation. Very cool.
