Hello, I am a DJ who wants to bring friends and other people together with small size parties, so I recently decided to acquire some used passive gear. It's not finished yet, but for now I just have 2 JBL MP215's being run from a QSC GX5, and I got a Yamaha SW118V that I thought would be good paired with a Crown XLS1002 in bridged mode, but it was not loud enough to really be heard/felt over the tops during outdoor performance. Keep in mind I did not have a crossover to take some of the bass out of the MP215's. Perhaps the sub would sound louder facing a wall indoors, but I haven't checked that yet. So now I have a few options, and wanted to hear people's opinion. I'm pretty sure that I should try and sell the sub and go with something like a QSC kw181 if I could find one. I could replace the amp with something more powerful, but I still also need to get an EQ and crossover, was thinking of getting a dbx driverack pa as an all-in-one solution. Though with the QSC sub I believe that would crossover the main speakers for me? Or I could choose to try and get another SW118V and run them in parallel at 4 ohms, but I'm pretty sure there are other subs out there that are of smaller size, hit harder, and are better in general. Not to mention I don't have a vehicle that can carry massive equipment right now, so more compact is better.
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get a dbx driverack pa and also an ECM8000 measurment mic. Then use the mic to set up the crossovers and system EQ. Your kind of shooting in the dark atm! high pas filtering the JBLs should clean up the midrange and allow an increase in system volume before unaceptable distortion. When equalising the sytem familirise yourself with common 'house' curves used in PA. Good luck!
Start upgrading to all powered boxes it will make your life so much easier... less gear to carry and no trying to figure out processing for them. The one catch is that tops and subs should be from the same brand as the crossover processing is often not executed the same way from one brand to another and you can easily end up with a situation where you still don't have a proper crossover for one box or another.
Also If you go with 18" subs there's really no need for 15" tops... the slightly better bass response of the 15 is moot when the crossover is applied.
Also If you go with 18" subs there's really no need for 15" tops... the slightly better bass response of the 15 is moot when the crossover is applied.
single 18" in reflex.
Linear excursion isn't as high as you think.
No need to bridge because real world power
levels no where close to bridged.
Just overheats the amp and tortures the power
supply. Needs crossover low pass 60 to 80 Hz
Then Over excursion filter. High pass
below reflex tuning. 27 to 35 Hz
More power yes is needed.
1 speaker only does so much.
Not always about power.
About moving air and enough cone area
to do it. So current amp is fine really.
Since actual linear power levels ( distortion)
is way way way below manufacture thermal rating
Simply crossover yes will help.
If sharing same bandwidth could cancel
each other.
Absolute minimum would be a pair of 18"
real world outdoors closer to 4
more like 6.
My default vehicle since I was 16 was a Truck
or Van. For the love of sound and high SPL
pretty much mandatory. Or alot of really
nice reliable friends
18" wants 5 to 7 cubic feet of airspace
x2 or x4 law of physics wont be broken with
a hatchback
Linear excursion isn't as high as you think.
No need to bridge because real world power
levels no where close to bridged.
Just overheats the amp and tortures the power
supply. Needs crossover low pass 60 to 80 Hz
Then Over excursion filter. High pass
below reflex tuning. 27 to 35 Hz
More power yes is needed.
1 speaker only does so much.
Not always about power.
About moving air and enough cone area
to do it. So current amp is fine really.
Since actual linear power levels ( distortion)
is way way way below manufacture thermal rating
Simply crossover yes will help.
If sharing same bandwidth could cancel
each other.
Absolute minimum would be a pair of 18"
real world outdoors closer to 4
more like 6.
My default vehicle since I was 16 was a Truck
or Van. For the love of sound and high SPL
pretty much mandatory. Or alot of really
nice reliable friends
18" wants 5 to 7 cubic feet of airspace
x2 or x4 law of physics wont be broken with
a hatchback
its possible to fit a potent system in a hatchback if you are willing to sacrifice <40Hz. The prescription would be something like:
Admark AD442 amplifiers
Small 15" reflex subs with something like 15DS115-4 I believe @chris661 has a design that is high output and very small
PM90 (expensiver) or SynTripP tops (cheaper)
some kind of DSP, ideally with the capability of multiple output limiters and FIR processing
Admark AD442 amplifiers
Small 15" reflex subs with something like 15DS115-4 I believe @chris661 has a design that is high output and very small
PM90 (expensiver) or SynTripP tops (cheaper)
some kind of DSP, ideally with the capability of multiple output limiters and FIR processing
Here we go:
https://www.diyaudio.com/community/threads/teeny-tiny-pa-15-subwoofer.272492/
It looks like some of the images aren't working, but hopefully there's enough there to be working with.
A pair of them with a good amount of power would give a decent amount of punch, with a useful amount of 40Hz grunt. A lot of smaller PA systems are rolling off by 55Hz, and having something that's flat down to 40Hz gives a noticeably more tactile feel to the bass.
I've since transitioned to some high-excurison 18"s in sealed boxes. I like the flexibility of being able to choose low or loud, and the cabinets are small either way.
NB - the drivers used above will be a massive step up from the Yamaha sub. Heck, I expect a high-end 12" would easily keep up.
Finally, a question: was the Crown amp hitting the red lights at all?
It might be the case that you simply didn't turn the subwoofer up loud enough.
Chris
https://www.diyaudio.com/community/threads/teeny-tiny-pa-15-subwoofer.272492/
It looks like some of the images aren't working, but hopefully there's enough there to be working with.
A pair of them with a good amount of power would give a decent amount of punch, with a useful amount of 40Hz grunt. A lot of smaller PA systems are rolling off by 55Hz, and having something that's flat down to 40Hz gives a noticeably more tactile feel to the bass.
I've since transitioned to some high-excurison 18"s in sealed boxes. I like the flexibility of being able to choose low or loud, and the cabinets are small either way.
NB - the drivers used above will be a massive step up from the Yamaha sub. Heck, I expect a high-end 12" would easily keep up.
Finally, a question: was the Crown amp hitting the red lights at all?
It might be the case that you simply didn't turn the subwoofer up loud enough.
Chris
I have finally finished my 15" PA style sub inspired by Chris' thread. Nothing to write home about - RCF LF15X401 in a BR box tuned to around 40 Hz with a large and long port. No time for measurements yet, but it shakes the house pretty well🙂 So I can definitely recommend that as well. One of the sound guys I rented used a pair of similar subs on a small metal festival and I could not complain about lack of bass.
as long as you hit 40Hz loud no one is going to complain about the bass. 30Hz is better and at our gigs we get there but its a lot of effort to get there and its better to be loud at 40Hz than going down to 30Hz and hitting limiting/clip.
Alright, so I'd like to give an update on the situation. I took Kipman's advice and got a DBX Driverack PA +, as well as the ECM8000. Currently just waiting for a couple XLR cables to arrive in the mail so I can hook it all up. In the mean time, I set the system up just how I normally would have, but changed the crossover on the crown amp to a bandpass between 40-100hz. I decided to try turning the sub around 180°, so it would be hitting the wall instead of facing forward. I know this may not be super accurate, but I found that it made a great improvement to actually feeling the bass all around the house. This got the house and glass vibrating, and I could hear it pumping nice from outside : ) The problem is when I turn up the volume up to a certain point, the MP215's metal cages start to rattle a bit, so looking forward to taking a bit of that low end out, and then being able to push it further as previously discussed. If that didn't totally remove the vibrating issue, does anybody know if it would be worth it to try and remove the cages to insert little foam pads in there to maybe absorb some of that? That is just a thought a friend and I had, but I feel like it shouldn't really be necessary.
In response to Chris, no I never hit the clip light on the sub amp yet. I do have the channel A turned all the way up as is suggested for bridged operation in the crown manual. I think I may have needed to turn up the gain a bit on the YamahaMG10xu.
In response to Chris, no I never hit the clip light on the sub amp yet. I do have the channel A turned all the way up as is suggested for bridged operation in the crown manual. I think I may have needed to turn up the gain a bit on the YamahaMG10xu.
hmm if you got a better result turning your sub around 180 deg i would be looking at the phase and polarity of whatever drivers are being used,no?
Hi, we are in New Zealand. We use QSC KW181 subwoofers and QSC K12.2 Speakers at our sound hiring company. I must say that these are brilliant speakers and especially KW181 subwoofers are great. If you want to see our client reviews and other information about QSC KW181, you can view it here https://starsounds.co.nz/