VP1800S | Portable | Loudspeaker Systems | Behringer | Categories | Music Tribe - Behringer
This my "B" rig but daughter (DJ) still managed to blow it. Would like to keep it cheap. Leaning on the blowout B52 $100 at Parts Express but curious what the bright minds here might suggest. I can post my HR data if you want but is basically run of the mill BR.
Thanks in advance!
This my "B" rig but daughter (DJ) still managed to blow it. Would like to keep it cheap. Leaning on the blowout B52 $100 at Parts Express but curious what the bright minds here might suggest. I can post my HR data if you want but is basically run of the mill BR.
Thanks in advance!
internal volume and port dimensions? not much xmax on the B52 but probably the VP1800is tuned high anyway. Are you running a high pass filter?
HR info attached if you want to import. Agreed B52 low xmax but probably better than stock driver. Not running active XO or HP on this rig but wonder if built into DSP of the amp module.
161.8L volume
144.8 sq cm port mouth and 47cm length
161.8L volume
144.8 sq cm port mouth and 47cm length
At 400w of real power output(the 1600w rating is pure marketing BS) I'd say one of the B52 buyout drivers would be fine.
P.S Looks like this driver models pretty well in that cab.
P.S Looks like this driver models pretty well in that cab.
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Thanks. Agreed power is bogus.
Am I nuts? Here is sim for this driver... Eminence B stock 15" subwoofer
and check it out xmax's out st 400W...
Am I nuts? Here is sim for this driver... Eminence B stock 15" subwoofer
and check it out xmax's out st 400W...
The port looks to be too long to get maximum output from the sub, in hornresp I get a tuning of 21.5 Hz. This is ignoring that this port been a slot port at the bottom of the sub will likely have an apparent length longer than normal. It looks like a much shorter port tuned to around 35Hz would maximise output for the Celestion T5867A; yielding around 120dB/1m and -3dB ~30Hz.
Also the linked sub doesn't have an amp built in, are you using an external amplifier? should always use a high pass filter for vented subs used in PA to prevent driver damage and maximise output capability.
Your posting the response not the hornresp record 😉
That driver has great specs for the price but is only 15" so its going to require some box modifications. Due to its massive xmax it displaces more air than the 18" though so should have more low bass output. If it where available in the UK I would order 8 of them...
SORRY. Yes, mine is powered. VQ1800D | Portable | Loudspeaker Systems | Behringer | Categories | Music Tribe - Behringer
Also, not sure I what I messed up but will post correct HR export when I can. I really want some input because it looks too good to be true. Flat to 20Hz. Not much output improvement however.
Thank you however, you are confirming my suspicion this driver might be good. Running box modifications through my head now. Leaning on a square plate mounted on baffle with rabbit recess for driver but need to verify it will fit.
Anyway, not my A rig but this setup is great for small gigs and pretty crazy to me since all active and so little to setup.
Also, not sure I what I messed up but will post correct HR export when I can. I really want some input because it looks too good to be true. Flat to 20Hz. Not much output improvement however.
Thank you however, you are confirming my suspicion this driver might be good. Running box modifications through my head now. Leaning on a square plate mounted on baffle with rabbit recess for driver but need to verify it will fit.
Anyway, not my A rig but this setup is great for small gigs and pretty crazy to me since all active and so little to setup.
ah so this caught my eye:
"State-of-the-art 500-Watt Class-D amplifier with comprehensive over-excursion, thermal and clip limit protection"
The over excursion protection is going to take the form of frequency dependent voltage limiting for the existing driver which means if you put in a driver that is capable of more excursion then the existing driver the amplifier is going to limit and you won't be able to use that extra excursion capability to generate low bass. So you would be much better off picking the more efficient 18" driver Celestion driver that is a better fit for the built in limiter than the 15" buyout.
Great catch! THANKS That went right over my head. Do you think there is some form of basic HP filtering?
yep probably, if you have a multi meter you could try putting a signal in at different frequencies and recording the amplifier output voltage to get an idea of the frequency response. You could also use a resistor divider and a computer with REW to get the gain Vs/frequency, this could be done at different levels to see if the hypothesis about the excursion limiting mechanism is correct.
Try shortening the port to 16cm and you will see that the maximum output of the box goes from 110dB to 116dB which is equivalent to having twice as many subs all while still going down to 30Hz which is enough for music, even things like floating points.
Not really sure I want another 6db. Said no DJ ever. Thanks! Seems odd the box is tuned so low. That mod also flattens the response considerably. Cut won't probably won't be pretty but at least it will be hidden!
I think there may be a discrepancy in your port dimensions, which would explain the unusually low apparent tuning.
Doing some very rough scaling from the pics on B's website, it looks like each of the 2 ports is about 23.8cm wide by 9cm high, for a total of 418 cm^2 rather than the 144.8 you mentioned earlier.
Also, I don't think your box volume was net of the space occupied by the port, driver, handles, bracing, amp module etc, right?
It needs to be net of all those inclusions for accurate modelling. The port alone will eat into the total internal volume of the box by at least 22l, depending on how far forward of the baffle its front end is set.
That means net Vb could be as low as approx 125l, which coupled with the revised vent area could raise the existing tuning to approx 35Hz, much more in line with expectations for this type of cab than the 21.5Hz noted earlier.
Please, don't start cutting the vent shorter until you've double checked all the relevant dimensions and revised your HR models.
Doing some very rough scaling from the pics on B's website, it looks like each of the 2 ports is about 23.8cm wide by 9cm high, for a total of 418 cm^2 rather than the 144.8 you mentioned earlier.
Also, I don't think your box volume was net of the space occupied by the port, driver, handles, bracing, amp module etc, right?
It needs to be net of all those inclusions for accurate modelling. The port alone will eat into the total internal volume of the box by at least 22l, depending on how far forward of the baffle its front end is set.
That means net Vb could be as low as approx 125l, which coupled with the revised vent area could raise the existing tuning to approx 35Hz, much more in line with expectations for this type of cab than the 21.5Hz noted earlier.
Please, don't start cutting the vent shorter until you've double checked all the relevant dimensions and revised your HR models.
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Once you have your new driver you can check the actual tuning quite easily by using REW or similar software to find the frequency at which the cone movement is minimised.
THANKS. Got out my metric tape and you are correct. Way off. Ports are 8cm x 22.5cm so 180 per and 360cm2 total. Probably messed up through my inches to metric conversion. Good eye! I did a decent job of using internal measurements and an estimate for driver but admit I could be more accurate. At this point I will try the driver and see how it performs before any mods as it seems logical they would have not tuned this design that low.
So happy I posted. Thanks for the help thus far!
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