Hello.
I would like to know how/if I could add some subs/bass bins to my PA system.
I'll start by describing it. It's a passive system. We have a Behringer Europower PMX2000 mixer. On the back it says:
Stereo mode: 250 watt at 4ohm, minimum 4 ohms
Bridge mode: 500 watt at 8ohm, minimum 8 ohms
Then there are three speakon outputs. One says
right/mono main, the second one says
bridge, and the third says
left/monitor. We currently have two Studiospares 248210 speakers. Here are the details for the back of one speaker:
It has a jack input which we use. Underneath this are two speakon inputs side by side, they are labelled as full range inputs. It says
max power: 500w peak, 250W RMS(PROGRAM). Impedance: 8OHMS, Crossover 2000Hz
If I want to connect some subs:
What sort do I need? How would I connect them? What watts/ohms should I get?
I can't say I fully understand any of the information I provided
, so any help would be much appreciated! Thanks.
I can try to provide pictures if that would be helpful.
Comments
1 Add some passive subs that have a crossover built in so you go out of the mixer amp into the sub and out of the sub to each top speaker.
Easy but you don’t get a huge amount of power.
2 Add some active subs and go from a line out on the mixer amp to the subs and connect the top speakers as normal from the amp. The down side is the top speakers are still getting some of the bass frequencies so the system isn’t as efficient as it could be.
3 You could keep your mixer amp but use it just as a mixer and add a bigger power amp and then connect to passive subs and your current speakers like the first option.
4 Keep the mixer amp as a mixer only and add active subs and tops.
Sell it all all and buy a separate desk and active subs and tops - this is how I run mine so I can add in as many speakers as I need for the gig - last weekends gigs used one sub and two tops and another I used 6 subs and 4 tops.
There are probably several other ways but those are the obvious ways that cone to mind.
In my view the major advantage of having subs is that the bass can be kept out the tops, so the tops can amplify the vocals more clearly; adding subs without being able to roll the bass off into the tops could actually make your live sound worse.
Why did you want to add subs anyway?
I do John_P's '2' - I run mine with a pair of Celestion 1x10" cabs and a single Wharfedale 250W powered sub bass bin, which I simply connect to the main/mono output and let the frequencies take care of themselves. (With monitors driven from a separate small power amp, from the monitor mix output.) It works fine for the sort of level of gig you'll be using a system this basic at - it's not technically correct or quite as efficient as it could be, but when you get to the point that sort of thing really matters then you need a bigger and more sophisticated system anyway.
If you aren't using monitors, you could get a better mix by using the monitor output to send the bass instruments to the sub(s) and take the 63Hz sliders right down to fully cut on the main mix, which would stop the lowest frequencies getting to the top cabs.
You may only need one sub - they're not directional - but two would give you a self-backup system and allow you to mount both top cabs on the subs with simple poles, and not bother with stands.
(NB, I probably wouldn't get a Wharfedale - I made mine from two dead ones I was given! They are not renowned for reliability...)
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
ICBM- thanks for your detailed response. We aren't using monitors (we tend to get by without, and at larger gigs we use the provided PA, not ours), so I like your second suggestion, especially as I coild get a better mix.
What brand would you recommend? Is it a good idea to buy used (cheaper) or is that considered risky?
If you’re not using monitors, definitely get a powered sub (or two) and run them from the monitor output with just the bass, keyboards and kick drum going through them, and cut the 63Hz in the tops.
I’m not actually that familiar with currently available brands, but I think your best plan is to buy a pair secondhand - cheaper, and if one fails you’ll get through the gig on the other. (Unless you’re unlucky, like the previous owner of my Wharfedales! And even those didn’t fail at the same time.)
Actually even Wharfedales are probably OK, and they’re fairly common and cheap.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
What is your budget?
For our smaller gigs (audience of one hundred and under) the rumble 25 manages on full volume. But the drummer isn't extremely loud, and I usually play through my Champion 100 at gigs. What size/watts bass amp would you recommend? We don't want anything too large.
Really cheap PA gear is usually a waste of money, it will inevitably break even if it sounds OK. Wharfedale would really be the lower end of what I would bother with.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
It's actually a transistor preamp with a valve power amp. I wouldn't describe it as very loud though... I think we must have different ideas of what loud is, if you can gig with a 25W bass amp .
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein