What's wrong with using just one sub?

[7thson]

What's wrong with using just one 18" sub?

 

We are a three piece rock band (guitar, bass, drums) that plays for 150 to 300 people, indoors and outdoors. This is what we have.

 

2 QSC RMX2450 PA

2 Yamaha 15" mains

1 Yamaha 18" sub

2 Yamaha 12" monitors

 

(and some various rack stuff: xover, FD, Comp, Sonic Max., EQ)

 

Bass is DI'ed thorugh a SansAmp to the board

Electric Guitar is mic'ed, Acoustic is DI'ed

Drums are mic'ed and submixed before going to main board (except Bass Drum Mic)

 

We use one of the QSC's on the mains (1 per channel)

We use one channel of the other QSC for the Monitors and the other for the sub that sits in the middle of the stage in front of us.

 

Everything sounds fine to me and I've heard from people in the crowd that it is one of the better sounding setups they have ever heard (clean, crisp, not obnoxious, etc.). But... I have a lot of musicians/sound guys looking at me funny when they see that we have just one sub. And, I've seen alot of people on this forum tell people to always get two subs.

 

Can someone tell me why this is so bad?????

[tlbonehead]

Originally posted by 7thson What's wrong with using just one 18" sub? We are a three piece rock band (guitar, bass, drums) that plays for 150 to 300 people, indoors and outdoors. This is what we have. 2 QSC RMX2450 PA 2 Yamaha 15" mains 1 Yamaha 18" sub 2 Yamaha 12" monitors (and some various rack stuff: xover, FD, Comp, Sonic Max., EQ) Bass is DI'ed thorugh a SansAmp to the board Electric Guitar is mic'ed, Acoustic is DI'ed Drums are mic'ed and submixed before going to main board (except Bass Drum Mic) We use one of the QSC's on the mains (1 per channel) We use one channel of the other QSC for the Monitors and the other for the sub that sits in the middle of the stage in front of us. Everything sounds fine to me and I've heard from people in the crowd that it is one of the better sounding setups they have ever heard (clean, crisp, not obnoxious, etc.). But... I have a lot of musicians/sound guys looking at me funny when they see that we have just one sub. And, I've seen alot of people on this forum tell people to always get two subs. Can someone tell me why this is so bad?????

There is nothing really bad about the concept of a single sub cab if it will move enough air to keep up,and you have time-aligned it as best as possible. The problem is that a single 18" (especially a lower budget simple vented model like the Yam) will not move enough air to get the low end volume up where it needs to be. For a pair of decent 15" two way cabs,I'd want at least 3,probably 4 of those subs in order to get where I needed to be volumewise. I've run subs in front of the stage in the center on outdoor stuff in the past. We used to have three of the old JBL refrigerator dual 15" sub scoops and instead of putting two on one side and one on the other,we just centered the three of them in front of the stage,which was usually a semi flatbed,which is almost exactly 4' off the ground. The same height as the sub cabs. It had surprising thump,and the young girls loved to jump up and dance on them towards the end of the night. Had our share of attempted stage-divers too!

[7thson]

We get girls that like to straddle it while we thump a low "G" on the bass.

[7thson]

We plan to get another Yamaha 18" sub in the future and run it through the second channel of the 2nd QSC and get another power amp for the monitors.

 

Wouldn't anything more be overkill for small bars with about 200 people? Would the second sub be enough for the few outdoor gigs we paly?

[tony k]

Uh oh. You've opened a can of worms my friend! I use two dual 18's or two dual 15's for crowds of 30 to 250. Thirty it's overkill but sounds wonderful. 250 it's a bit lacking. Would love to pick up another set of the dual 18's but cash is a little short

[URSavage]

My Band runs one SUB cabinet, a dual 15" JBL. The crossover is configured to run summed mono and I power it with a 1600W bridged QSC amp.

 

For the small venues that we play at it does a nice job of adding some thump. ~ 150 people.

 

At the bigger venues - I really would like to be adding a 2nd cabinet...

 

 

As for outdoors; in my limited experience this really is a whole different ball park. It really depends on the size of the crowd and how far you need to be pushing the sound.

 

Unless the setting is very intimate, or you are providing a bit of background music - it very quickly becomes the job of the professionals...

 

Well just my 2 cents.

RUs

[Old Steve]

Good points so far...

 

One thing to consider as well (and is often overlooked with posts like these) is to manage your expectations.

 

As others have said, running with one sub isn't necessarily a problem, but two would be better. In general, more (at least PA wise) is usually better, assuming it's run properly. It's always easier to turn down or unplug a too-big rig than it is to make a too-little rig sound good if its pushed too hard.

 

Bottom line, you need to find a way to hear what your rig sounds like in your typical venues...if it's too weak, build it up...if you're happy with it, don't fix it.

 

As for outdoors, these guys are right saying it's a whole new can of worms with plenty more to consider. But how often do you play outdoors and what is a typical outdoor gig for you. I've seen plenty of bands play at the local town park with nothing more than some speakers on sticks...obviously this is inadequate for loud thumpin rock and roll, but it does just fine when the senior citizen swing band is performing for their peers! If you seldom play outside, and/or those gigs consist of playing for free beer at your buddy's barbeque with a couple dozen friends, you don't need to spend any more money. Then again, if these are higher profile paying gigs where you expect a real crowd, you'll need more gear. In the end, it might be more economical to hire/rent if these kind of gigs are infrequent.

[Tommy Tune]

We're running 2 EV force subs but I'm thinking about adding another in the middle to experiment.

[Rbts]

I was looking at a post over at sweetwater, that sent me to a link where there was an article that made a convincing argument for the idea that no matter how many subs you run, it might be best to place them altogether somewhere as a group... to minimize the phase cancelation that typically accompanies the lower frequencies when the subs are placed apart from each other.

 

Any comments to this?

[agedhorse]

Originally posted by tony k Uh oh. You've opened a can of worms my friend! I use two dual 18's or two dual 15's for crowds of 30 to 250. Thirty it's overkill but sounds wonderful. 250 it's a bit lacking. Would love to pick up another set of the dual 18's but cash is a little short

I see 2 more sub cabinets in your future!

[RamRodRacingMt]

If we have more people than our amps can handle i just hire a sound guy.... We have a pair of 15in mains for vocals and minor guitfiddle if we need it. If we need more than that I ring up the local sound guy.

[Scodiddly]

If you like the sound then your single sub is doing its job.

 

For indoor gigs you can play around with location, especially trying to find a good corner to put the sub in. Room coupling will make a big difference in efficiency.

[Sugarfried]

The rig I work on most of the time has a single 18 for subs. Most guest engineers look at the entire rig (which is 2 EV DeltaMax 12's and this big ass 18" bin for the sub) and immediately wish they had brought their own rig. At the end of the night they all say the same thing: Damn, I got way more lows than I thought I would.

My room is 200-250 capacity, and at 250 it's like a sardine can. So the room is small enough to only need 1 sub. Back when we ran 2 there was cancellation in certain parts of the room. When we only use 1 it's more evenly dispersed.

Just to thwart any doubters, early in the night I usually play something at a loud volume. I make a few EQ adjustments so that it looks like I'm doing something, but I'm really just cranking it for the sake of showing that the PA has balls.

 

So IMO, in some situations 1 sub is more than adequate, but the same PA in other rooms would require more than 1.

[rickkreuzer]

One of the great things about subs is that if your bottom end is where you like it, you're fine. If it isn't, you just add more!!

 

If your sub is crossed over properly, it should almost be impossible to localize. See, a sub is supposed to be omnidirectional. It's more felt than heard. There are, of course placement options where you'll be able to utilize your surroundings for your desired effect. For example, if you place a sub in a corner, you'll get more boom. If it's standing alone without any walls around it, you'll get more crispness.

 

Most bands make the mistake of overdriving their subs. They expect to get the same thump outdoors as they do in a small club with the same equipment. It just ain't gonna happen.

 

Rick

[tony k]

Originally posted by agedhorse I see 2 more sub cabinets in your future!

 

LOL I'm an easy sell as you know