Punisher plots
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Category: Plans
Forum Name: Punisher and X-tro
Forum Description: Discussion / Questions about the Punisher and X-tro
URL: https://forum.speakerplans.com/forum_posts.asp?TID=33742
Printed Date: 27 March 2026 at 8:25am
Software Version: Web Wiz Forums 12.08 - https://www.webwizforums.com
Topic: Punisher plots
Posted By: doober
Subject: Punisher plots
Date Posted: 16 December 2009 at 9:55pm
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I don't recall seeing any measured plots of punishers on here, so I took four into a field and did some measuring.
Pic shows measurements of 1,2,3,4 punishers. It should be obvious which trace is which. Measurement was groundplane (middle of a soggy field), a good distance from any buildings, four speakers stacked longways with mouths coupled. Mic was berry ecm8000, on a short stand, mic tip nearly touching the ground, around 2m from the cabs. Pre amp was small soundcraft mixer, output taken at insert point on mic channel. Soundcard is cheapo 2 in 2 out berry thing, software calibrated to match. The spl is not calibrated, power input to speakers unknown, just enough to get a good level for measuring, maybe 50-100w per cab. Amp was (you guessed it!) a berry ep2500. I used this because its lighter than my main rack, it will drive 2ohm loads, I'm not bothered it it gets rained on or covered in horsey poo. The amp levels were set for the first sweep then not changed for the rest as more cabs were plugged in. This means the total impedance lowered, 8 - 4 - 2.66 - 2 ohm, and therefore total power input rises with each cab added, power per box drops. I though this was the most realistic way to compare plots rather than trying to make it a constant power at each sweep. The results certainly surprised me....... 
I'm not sure why there are those notches on the single cab and three cabs measurement. Any comments? Kieran ------------- Blahblahblah |
Replies:
Posted By: Peter Jan
Date Posted: 16 December 2009 at 10:43pm
In fact power per box doesn't drop if not driven to maximum (clip). The graphs show it too, roughly 6dB more for each doubling of cabs, apart from the respons nicely flattening out to the low side, the more cabs play together.
Seems logical that 1 or 3 has a notch and 2 or 4 don't if they were on their side. I don't know if you measured only 1, 2 or 3 cabs connected in a stack of 4 or with 1,2 or 3 placed on their own for each measurement. Might be intresting to see how dips would occur (or less or not at all) if the cabs were placed with the mouth(s) to the soil or floor, meaning the underside of the cab(s) down. The majority of waves are found in that part of the mouth and as they 'see' an open space when exitting the horn or a cavity from another cab that's not connected to the amplifier, they will behave different than when they 'see' a mirror from the soil/floor or another cab that has the same waves propagating and adds the SPL, instead of disturbing it in some way. For one cab it's a dip that goes down about 7dB around 75Hz and that's a serious problem for a bass cabinet. Two cabs still behave somewhat funny, but less obvious than one. Three cabs have the same thing going on as one, less dip, but not as smooth as it should be or could be. At some points three cabs go a tad over the response of four and even if it's not in the area the cabs will be used in, it's an indication that this kind of placement on his side has issues. From four cabs on and more, the erratic behaviour is largely gone. On a side note let me tell you that I had the same thing going on with KF940 cabs I used about 10 years ago. Stacks of four or more with mouths coupled, worked great, but three had to be with mouths down to the floor or the 'punch' was gone. I never took the time to measure it up, as I didn't find it exiting to know precisely how much and at what frequencies the trouble occured. I knew what caused it and worked around it. Some folks suggested to EQ it out, but this kind of problems can't be EQ'd out, only destroy speakers with no significant effect on respons whatsoever. The placement is the problem, not the response of the cabinet(s). |
doober wrote:Posted By: Ibex
Date Posted: 17 December 2009 at 7:08am
What would you recommend for stacking two cabs? Bottom to bottom of each cab lying on their sides or both with their bottom against the floor? |
Posted By: Peter Jan
Date Posted: 17 December 2009 at 11:14am
Both with bottom against the floor for sure. Or on their side in a corner is also good.
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Posted By: darkmatter
Date Posted: 17 December 2009 at 11:38am
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Thank you VERY much! Really useful to have some proper info on this :)
Kinda raises the question of whether these can be used up to ~140hz when in a larger stack. People report honk at 120hz and that's pretty evident in the graphs for 1 and 3 cabs but not in the 4 cab response.
When you measured with just 1, 2 or 3 cabs, were the other cabs still part of the stack and not switched on? If so I'm guessing an unpowered cab in close proximity to the others could have some effect?
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Posted By: Peter Jan
Date Posted: 17 December 2009 at 12:04pm
The honking sound occurs with only one or two cabs, because the response is not as good down low as with more cabs ( 4 and up ). I tested with several speakers beside the Ciare and other speakers did better higher up than the Ciare, but all had decent response above if used in multiples. The Ciare starts to lose SPL faster than other speakers, but it's very useable till about 200Hz. The Punisher design is not meant to be used that high anyway, too many folds that cause refraction. It's not bad design thing, but a inevitable property of bend/folded bass horns.
It certainly does have effect !
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Posted By: toastyghost
Date Posted: 17 December 2009 at 12:29pm
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I’m not sure how useful this is with the way it’s been measured. Using a calibrated SPL measurement rather than an RTA mic would be a start, but at the very least they should have been measured with a standardised amount of power into each impedance.
Also, is the single cab measurement on it’s own entirely, with the other three cabs many metres away, or was it just one cab powered in a stack of four? |
Posted By: Timebomb
Date Posted: 17 December 2009 at 1:26pm
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How much power your giving them dos not really matter if your not measuring spl, and if you haven't got calibration kit and expensive mics i dont think there is an awful lot of point in measuring SPL. it gives a good idea of frequency responce though, thease plots seem to tally well with the plots i took in the summer, theres a couple of dips on mine but they came with every speaker, so proximity of walls would account for that. http://forum.speakerplans.com/got-a-lot-of-plots-eh-wot_topic28237_post281115.html?KW=plot#281115 - http://forum.speakerplans.com/got-a-lot-of-plots-eh-wot_topic28237_post281115.html?KW=plot#281115 Seem to run smooth to about 42-43HZ then drop off sharply. Anyway, nice one Doober for taking the time to do this! ------------- James Secker facebook.com/soundgearuk James@soundgear.co.uk www.soundgear.co.uk |
Posted By: doober
Date Posted: 17 December 2009 at 3:53pm
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Shortly after posting the plots I realised what was causing the dips. For the plot of one box I had an unpowered box sat on top. For the plot of 3 boxes I had a stack of four, one unpowered. It would seem that the unpowered box is sucking a bit of the energy from the powered one at those points. The fact that the dips are smaller on the 3 cabs plot backs this up. I might do an impedance plot today, it will be interesting to see how the peaks compare frequency wise with the dips seen on these measurements.
It would have been nice to do plots with a standardised amount of power and a calibrated spl meter, but we had a lot of cabs to measure in not much time, and it was getting dark. It seemed much easier for the sake of comparison to set everything up once and then not adjust the gains between tests. I also took plots of various reflex and bandpass boxes while it was set up, just to compare rather than to get any absolute measurements. I'm also a bit sceptical about the level of the plot for 4 cabs. I initially set the levels to get a good reading with a 15" peavey reflex cab. By the time we got to 4 punishers the spl was considerably higher and the soundcard input was getting close to clipping. The results are certainly of use to me, I am interested in the shapes of the curves more than the levels, and it should show that it is not absolutely necessary to use a stack of four or more at all times. I'll put up a plot comparing 2 punishers with a 18" reflex later. Kieran ------------- Blahblahblah |
Posted By: darkmatter
Date Posted: 17 December 2009 at 4:03pm
Ah makes sense now, thought that might be it.
Yeah same :)
The results suggest to me that regardless of stack size, high passing above 40hz is safest. Previously I was never sure whether low pass could be taken lower with a larger stack. Guess the only way to be certain would be with a fancy excursion measuring laser, I don't have one of 'em though :P
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Posted By: toastyghost
Date Posted: 17 December 2009 at 4:09pm
I’d never advocate reducing your HPF, regardless of stack size. You will naturally get a boost at and slightly below the HPF point through coupling but the excursion limits won’t change dramatically. |
Posted By: Timebomb
Date Posted: 17 December 2009 at 4:10pm
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Yeah 3 seem to sound a lot smoother than 2, i think there totally usable in 3s, what software were you using? ------------- James Secker facebook.com/soundgearuk James@soundgear.co.uk www.soundgear.co.uk |
Posted By: cravings
Date Posted: 17 December 2009 at 4:43pm
| would shorting the drivers in the unused boxes get past the dips in testing? just curious. |
Posted By: minaximal
Date Posted: 17 December 2009 at 4:48pm
that is a nice set of responses, a stack of three looks perfectly useable, slowly dropping 3dB from 70hz to 43hz. just dont forget to short the unused cab to get rid of the destructive interference. prog is: roomeqwizard and the berry / dayton mics are fairly reliably flat over this passband, i had a cal file made for mine and there was no deviation to worry about here. ------------- Subs + Barges = :) http://www.metaacoustics.com" rel="nofollow - www.metaacoustics.com |
Posted By: doober
Date Posted: 17 December 2009 at 5:12pm
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Shorting the unused driver may have helped, concentrating on what we were doing and only adding another cab at a time certainly would have.
I usually high pass mine at 42hz regardless of stack size, although I don't give them huge amounts of power, and I'm not keen on dubstep. Here's the impedance plot 
As I suspected the spikes are at the same place as the dips in the plots. My understanding of this is that the impedance spikes are caused by larger cone excursion (more back EMF), due to the horn acoustic resistance being lower at these frequencies (or reactance being higher?). This will mean that a cab playing next to it will move the unpowered driver easier at these points, absorbing acoustic energy. I'm still learning with this measurement malarky, this has definitely been a lesson for me. It would have been good to get some more plots with the cabs stood upright in a row, horns to the ground, and upright two high two wide with mouths coupled. Unfortunately time (and daylight) was running out, and I wanted to have a quick play with my new matrix 5000 whilst outdoors. That was painful, in a good way! Kieran ------------- Blahblahblah |
Posted By: doober
Date Posted: 17 December 2009 at 10:02pm
This plot is two punishers compared with 1 18" reflex. Its not really fair because there are two cabs to one, the two cabs get more total power due to the 4 ohm load, and the reflex box is a Behringer. The punishers will gain an extra 3dB due to there being two of them, and another 1.7dB due to the 50% extra power the amp puts out when running 4 ohm load. The point I'm making is that in some situations two punishers would be enough. The berry boxes sound a lot fuller than the plots would suggest, probably due to the rolloff being quite smooth. This sort of response is good enough for chart/pop etc parties, and for smallish band gigs. The punishers actually have a more gentle rolloff than the reflex box. Kieran ------------- Blahblahblah |
Posted By: VaultzPA
Date Posted: 25 July 2014 at 3:23pm
| What would you recommend 2 Punishers v2 or 2 18 reflex bins say for instance active ones made by Cerwin vega for use at Disco's and outdoor marquee parties. |
Posted By: doober
Date Posted: 28 July 2014 at 9:16pm
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If you already have the punishers- stick with them. A single 18" reflex cab won't be much smaller than a punisher, and will almost certainly not be as loud. If you are looking at disco/music shop subs you will probably need 4 to do the job that 2 punishers will do. ------------- Blahblahblah |