That doesn't sound right... Especially the 12.88" dimension.
https://www.amazon.com/Peavey-PV-118-Inch-Subwoofer/dp/B001Q5SGJK
I'm thinking this is the cabinet he's talking about. It matches his description of the port being in one corner. You can barely see it through the grille in the picture. Amazon gives 29.5" x 24.7" x 23" external.
So to see how that compares:
That's 274.6 Liters.
THAM 15 is 187 liters.
So that's 549.3L for 2 Peavey 118s if I got the cabinet right vs 748L for 4 THAM 15s. I think the extra flexibility of 4 cabinets vs 2 for packing arrangements means you can likely find that additional 200L of space unless your SUV is already crazy tetris-packed already.
I'm not saying the THAM option is the best option of all possibilities, but I've never heard anyone say they were disappointed after building one
.There was mention of trying to fit 2 keystones in an SUV. Having two myself, there's no way to get them both in my 2003 Toyota Highlander. Even for a bigger vehicle that could fit them, it would be a hell of a squeeze and you'll have quite a time getting the rest of your gear in.
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Chris,
Thanks for the correction, been months since I have seen my amps due to the cross country move, and my memory being shite.
I far prefer moving a single Keystone to the pair of 2x15" subs that take up the same space as a single Keystone while putting out less LF
.I plan to build a large BR shop sub, a pair of tiny PA/home theater subs, and two 19" racks, then sharpen my pencil for the new "Keystone B Low Sub™" plans.
I have a pair of B&C 18TBW100 on their way for one pair of Keystone B Low Subs, the other four will get the 15"s from the PPSL "Shoehorn" 2x15" subs, unless someone wants to purchase them loaded, shipping from 32720, make offer..
By the way, having done sound for outdoor shows with as many as 4000 people attending with a pair of Keystones, I would think the OP would be fine with one Keystone for club dates, if he uses the last 6 dB of his amp power (my previous post should have stated 250 watts instead of 100 watts, 4 dB more power).
That said, with his amp bridged mono he could get 2000 watts into a 4 ohm B&C, pretty close to what one would want.
Gotta get of the keyboard and start making sawdust...
Art
Sam,Wait a minute! OP didn't say cost was an issue... Does your SUV have a hitch?
I am liking the single Keystone idea.
I am liking the six Keystone idea, I'll fit four in the trailer, and two in the Outback (or one in, and one on top- have not checked if a pair will fit inside...).
The pain of an extra loading and unloading for each gig makes life without a trailer unimaginable to me.
Art
Xalanx,
2) You perhaps tested polarity, but you did not check phase. Your subs probably do not match the phase of your ported (phase inversion) top cabinets in the crossover region, which makes for a lack of "punch".
3) When the -10 light on your amp illuminates, it is only putting out 100 (peak) watts. You bought a 1000 watt amp, and are using 1/10th it's potential.
Kind of like buying a Ferrari and never taking it out of first gear
Art
2) how can one test polarity?
3) how do I get more power from it without clipping if it's already that close to doing so?
I had a buddy tell me that because I daisy chain my 2 enclosures that I'm sitting at 16 ohms??
Also, I feel like I may not be properly wired-through when it comes time to my whole rack set-up. I'm using the soundcraft ui16, and I'm running my subs from the headphone outs...is this stupid? There's only 2 main outs L/R, two headphone outs, 4 monitor/aux sends. The two main outs I have running to an ultramizer then to my tops. Whereas, the sub comes from the headphone out to the xover to the amp. Should I be using one main out for the tops and the other for my subs?
Hi Xalanx309,
Post #26: "...because I daisy chain my 2 enclosures that I'm sitting at 16 ohms?"
If the PV118 spec sheet from Post #22 is for your subs, then the connectors are in parallel, and you will most probably be looking @ ~4 Ohm as the amplifier load. Have you had a chance to take a look at what that internal Low Pass Filter in the PV118s is? That could be eating up some of your power.
Regards,
Post #26: "...because I daisy chain my 2 enclosures that I'm sitting at 16 ohms?"
If the PV118 spec sheet from Post #22 is for your subs, then the connectors are in parallel, and you will most probably be looking @ ~4 Ohm as the amplifier load. Have you had a chance to take a look at what that internal Low Pass Filter in the PV118s is? That could be eating up some of your power.
Regards,
You were already told how. Make sure you can identify the + and - line of your speaker wire. Hold a 9 volt battery momentarily to the speaker wire with the + of the battery to the + speaker wire and - to -. If the cone moves outward all is well. Perform this test with both cabs. (If both cones move inward it's ok, you can use the phase inversion on the amp instead of rewiring the subs.) Next make sure to wire it up with both subs in phase with each other. More on this later...
This was already explained. You are nowhere near clipping. If you don't see the final 0 db light lit up you are not clipping. Don't be scared to light that last light up UNLESS you fear that the subs are being stressed either thermally or mechanically. Both types of stress should be very audible long before you blow the subs up. Stressed subs make all kinds of nasty distortion, this is the equipment telling you it's not happy.
You can wire your subs in parallel or in series configuration. It has been assumed here that your subs are wired in parallel, giving the total load 1/2 the impedance of a single sub. If wired in series your total load would be 2x the impedance of a single sub.
At this point, before passing go, before collecting $200, before doing ANYTHING it is absolutely essential that you research series and parallel wiring and determine for yourself how your subs are wired and what impedance the total load is. I really can't stress enough how important it is to understand these basics of wiring and polarity.
Until it is 100 percent crystal clear that your subs are running in phase with each other and you know what impedance your total load is it's really impossible to help with any kind of recommendation on what you should be doing different.
If necessary draw a picture of your sub wiring connections (including labelled + and - connections) and we'll tell you. It's still up to you to figure out the polarity of the individual subs (cone in or out during a + pulse, it's absolutely necessary that both subs behave the same).
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The NU4-6000 put out more power, and drew only 50% of the power from the mains compared to the CA9, and weighs a small fraction of the "heavy iron".
I likes my new amps Berry Berry much
Art
Thanks for sharing your thoughts. Looks like I need to buy one of these amps for testing.
Are class D amps replacing conventional AB amps in the pro industry nowadays?
I did the battery test and they both popped outwards. I originally thought this meant they were in phase but I was told I was wrong and that perhaps I was checking polarity.
I've been told that daisy-chaining is technically wiring in parallel, and that prallel wiring divides speaker ohmage. Two 8ohm speakers (in separate cabinets) daisy chained by a speaker cable means I have a 4 ohm load, yeah? If so, that's what I'm working with, as explained in my original post.
How often is clipping acceptable? I usually try to get it where it only clips now and again, but never constantly.
I've been told that daisy-chaining is technically wiring in parallel, and that prallel wiring divides speaker ohmage. Two 8ohm speakers (in separate cabinets) daisy chained by a speaker cable means I have a 4 ohm load, yeah? If so, that's what I'm working with, as explained in my original post.
How often is clipping acceptable? I usually try to get it where it only clips now and again, but never constantly.
Yes, the battery test is checking polarity. Then you have to make sure that both the subs are in phase with each other (and with the mains) when you wire it all up. If everything is not in phase it will subtract rather than add. It's very important that all the +s and the -s get wired where they are supposed to go. In the diagram below if any of the + and - are swapped you get cancellation. It's still wired in series or parallel but out of phase.
First of all, we would be further ahead to stop saying "daisy chain". That could mean just about anything. You are either wired in series or in parallel. If you really don't want to look it up and understand it I'll show you pictures. This is important. Either of these could be called "daisy chain" if you wanted to, but it's more telling to say "series" or "parallel". Your wiring might not look exactly like either of these images but I can assure you, it's either wired series or parallel, figure out which. And make sure that your subs are in phase with each other (they both pop out at the same time) and in phase with the mains.
Yes, you only want it to clip instantaneously for a second at most. But the actual clipping light is the last one (0 db) not the second one (which I think Chris said is -6 db).
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Its definitely not conventional.
What is the model of that crossover? The correct way to wire this is main outs from the mixer to the crossover, high outs from the crossover to the amp powering the tops and low outs to the amp powering the subs. When you do this you will probably discover there are no lows at all coming from the 215.. which is what should happen. What you should then realize is that there really is no need for 215 mains unless you have seriously powerful subs, so you could swap those for 1x15 or smaller boxes(2x10) and then add more or upgrade your subs.
And if it were my rig I'd chuck that maximizer thing in the river but I understand some like what it does to the sound, if may be part of the problem you're having with coherence though so it would be worth taking it out of the circuit for testing.
After you get the wiring figured out and the gain set so that you are using all the amp's power and the crossover is set properly (preferably by measuring the response and tweaking) the next thing to work on is sub placement. Putting the subs far apart at the front corners of the stage (under the mains) is just about the worst place to put them.
Ideally the subs should be clustered (side by side or one on top of the other) and placed at a boundary, a floor/ceiling boundary or even better in a corner of the room.
After you've tried all that out, if it's still lacking, then it's time to talk about upgrades.
Ideally the subs should be clustered (side by side or one on top of the other) and placed at a boundary, a floor/ceiling boundary or even better in a corner of the room.
After you've tried all that out, if it's still lacking, then it's time to talk about upgrades.
So by now you should have tested polarity with a 9 volt battery.
You should purchase or borrow a V.O.M (volt/ohm meter), with it you could easily measure whether the pair of speakers are 4 or 16 ohms. Harbor Freight has a cool VOM for around $25 (IIRC) that also has a SLM (Sound Level Meter) so you can measure the level of your speakers (and your drums and guitar amps, etc.)
The DCR (Direct Current Resistance) of an 8 ohm speaker is generally in the 6 ohm resistance range, so the DCR will be around 3 or 12 ohms.
6 dB headroom is a not close to clipping, it is only 1/4 power- kind of like the speed of first gear in a four speed transmission compared to top speed in fourth . The amp has a clip limiter, so hard to do much damage to your Black Widows unless the clip light stays on for more than kick drum peaks. If the amp gain is not already wide open, simply turn it up.
If it is already turned all the way up, and your mixer's headphone output (W.T.F.?) is clipping before the amp, you probably need to use balanced connectors, either 1/4" TRS or XLR (mic cords) rather than 1/4"(guitar cord). A balanced connection will give either 3 or 6 dB more output, depending on your console or EQ output topology.
If you are using a headphone output via a T.R.S cord to the amp, signals mixed mono will have 6 dB less output than if you use the proper output.
To expand on my previous post regarding phase vs. polarity, if you were using DSP (Digital Signal Processing) you can adjust the phase balance between your tops and subs. Since you are not, all you can do is swap polarity between the two, and go with the combination that is louder at the crossover frequency.
It appears you using nothing to cross over (a crossover removes highs from the subs and lows from the tops) the subs to the tops, where is the face palm icon...
Art
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JAG,
For 80% of the live venues I have encountered, set up and measured systems in (that would be in the order of several hundred, not including outdoor facilities, which I work in more frequently) I would disagree with your advice, unless playing in a home living room sized joint, in which case you don't need anything but a vocal monitor in the corner behind the band.
To have proper time/phase alignment between the top cabinets and subs requires them to be located within 1/4 wavelength at the crossover frequency (34 inches, just short of one meter for a 100 Hz crossover), not possible when using two mains speaker locations and one off-center sub location. Center clustered subs using Left/Right mains can only be time/phase aligned for one audience position, unless the crossover frequency happens to be much lower than the typical 80-100 Hz generally used.
Granted, more output can be gained from corner loading, but in my opinion, the loss of "punch" and coherency through the crossover region is a bad exchange deal, unless playing drone-tone boom boom slop, in which case I'll defer to whatever the customer wants
.Art
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Jag,
Polarity and phase are related, but quite different beasts.
The subs must be wired in the same polarity with each other to gain 6 dB for the pair compared to a single.
The pair of BR (Bass Reflex/Phase Inversion) tops may need their polarity reversed to be in phase with the subs at the crossover frequency. If wired with the same polarity, they may be as much as -6 dB down at the crossover frequency.
The polarity choice between the tops and subs is also dependent on crossover slope (poles/dB per octave) and driver acoustical center offset distance, but since it appears the OP is not even using a crossover (!?!), no need to go into more explanations, unless you are interested.
Art
JAG,
For 80% of the live venues I have encountered, set up and measured systems in (that would be in the order of several hundred, not including outdoor facilities, which I work in more frequently) I would disagree with your advice, unless playing in a home living room sized joint, in which case you don't need anything but a vocal monitor in the corner behind the band.
To have proper time/phase alignment between the top cabinets and subs requires them to be located within 1/4 wavelength at the crossover frequency (34 inches, just short of one meter for a 100 Hz crossover), not possible when using two mains speaker locations and one off-center sub location. Center clustered subs using Left/Right mains can only be time/phase aligned for one audience position, unless the crossover frequency happens to be much lower than the typical 80-100 Hz generally used.
Granted, more output can be gained from corner loading, but in my opinion, the loss of "punch" and coherency through the crossover region is a bad exchange deal, unless playing drone-tone boom boom slop, in which case I'll defer to whatever the customer wants
Art
Yes, but ...
With a 80 hz crossover you have 42 inches to play with inside the optimal 1/4 wave zone. And things don't get really bad until quite a bit further out.
I'm picturing OP playing in small(ish) rooms with small(ish) stages, so the back wall is only a few feet to the mains and close enough to the 1/4 wave distance.
Also consider that in small(ish) rooms, the room is going to mess with the sound so much that it's not going to sound perfect anywhere regardless of the perfection of the setup.
And specifically in this case, the main (in fact the only) documented problem is not enough spl.
Considering all that I'd say it's well worth giving subwoofer boundary loading a shot. it may well be much better than the textbook perfect 1/4 wave crossover distance setup.
This is why I mentioned that it would be preferable to measure and tweak when setting up the crossover. This will make phase issues abundantly clear (if you know what you are doing).
I've got a good bit of experience with driver distances, crossover type and slope and phase, lobing, constructive vs destructive interference, etc, but at this point OP isn't even familiar with series vs parallel wiring so no need to write a manual on proper setup.
1) Xalanx309 has indicated he is not using a crossover.
2) Even in the smallest clubs, the usual distance from a cheezy 6 foot deep stage to where the usual weekend warriors place their mains speakers is at least 6 feet. Perhaps you frequent smaller parlors
.3) Agreed, but there is no reason to FUBR (FIBUR) sound before it reaches the patrons.
4) Which can be easily remedied by gain staging suggestions in prior posts.
5) Fix electronic problems with acoustical nightmares? Time for me to go to bed
.i don't even know if that emoticon is correct, but a dear protege (M.L.W.) known for over 3 decades is going to pass on soon, sorry for the drunk post.
Art
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I do in fact have a crossover. A dbx 223xl.
I'm not 100% sure on my ohmage so I may just buy the meter reader. I don't know if the tops are in phase (or polarity) with my subs. But my subs are in phase. I haven't tested both subs at the same time to measure the time of their reaction though.
I mixed things around and here how it's hooked up now. I now have just one output from the main R out to my crossover (is that ok? Or do I need to use both L and R outputs??), high out goes to the ultramizer (which I have bypassed) then that one line is split into L and R to my amp which is in stereo mode, and low out simply goes to the amp.
I'm not 100% sure on my ohmage so I may just buy the meter reader. I don't know if the tops are in phase (or polarity) with my subs. But my subs are in phase. I haven't tested both subs at the same time to measure the time of their reaction though.
I mixed things around and here how it's hooked up now. I now have just one output from the main R out to my crossover (is that ok? Or do I need to use both L and R outputs??), high out goes to the ultramizer (which I have bypassed) then that one line is split into L and R to my amp which is in stereo mode, and low out simply goes to the amp.
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