Bass through the PA?

[atinder]

I posted this over at Talkbass, but I thought some of y'all might have good info too. See below.

Sorry for the noob question, but I wasn't having much luck searching. I play in a trio, and we just got a fairly inexpensive PA - haven't had a chance to try it out at practice yet. We got two different opinions from two different employees of the shop: one said don't run the bass through the PA (just use the amp), and one said it would be fine. What's generally considered the "correct" way to go? Here's the basic info:

Band: guitar, bass, drums and two vocal mics. Music is rock, but not hard rock (alt/country, Stonesy bar rock).

PA: Behringer powered mixer (800 watts mono/ 2x 350), Peavey 12 inch speakers (rated at 400 watts). Not planning to mic drums, and our goal is small bars and perhaps parties.

Help? Thanks, and let me know if you need more info.

[psychetelec]

Run the bass thru the PA IF the speakers can handle it.
Will you have a soundman? If so, with the bass thru the board he will have more control of the sound.

[atinder]

But how do I know if the speakers can handle it? (I mean, without doing some kind of damage)

[bobbybigmac]

I'd like to suggest you only run vocals and acoustic guitars ( if any ) thru the PA.

You described a scenario that was very similar to my last band .
2 female lead vocals, both playing acoustics, yours truly on bass and
vocals, guitar and vocals, and drums. We played mostly country rock in a small pub. I'd guess up to 125 patons. PA was 800 watts, a small 10 channel mixer board, and Ev's combo 1x15 + horn cabs. No monitors.
We never DI'd the bass or miked the drums. I used my GK 4x10. Guitar player
had a Twin. Always sounded fine.

[cantolina]

In most small-venue situations, it'll do more harm than good....

The bass is generally something that can be heard without reinforcement in a situation like this...

In a small room, with a small PA, less is more...

"Correct", in this case, is more a function of necessity, than one of theory....

As with ANY instrument in a scenario like this....if you can hear it fine without reinforcement, it doesn't need to be in the PA...

As mentioned before....vocals FIRST....then, whatever you can't hear....

If there's no soundman...keep it simple...

For years, I did a little kick drum (sometimes), and vocals ONLY....

[Tim Armstrong]

I used a smaller amp and ran bass through the PA system for five years or so. Our main speakers are fairly heavy-duty Community Sound and Lights 15s, and they handled it just fine.

Then, back in May, after accidentally sending a MUCH hotter signal to the PA than intended, I slightly damaged one of the speakers, and it buzzed like a cheap TV whenever a low frequency signal hit it. At about the same time, I bought a 400-watt head, and being too busy to replace the damaged speaker (which worked fine as long as I didn't run my bass through it!), I began just using my bass amp like, well, most bass players do!

That's working for me just fine now.

So, while I still think a large enough PA system ought to be able to handle bass without problems, I now realize how close to the edge I was operating! I'm on board with the idea that a proper bass amp that's big enough to carry the room is preferable!

There, I said it!



Cheers, Tim

[franchelB]

I use my bass amp as MY monitor. I run a "line out" to the P.A. to give the bass drum a fuller sound.
BUT the only way I'd LOVE to run my bass through the P.A. is IF I had my OWN monitor mix!

"atinder": If you guys are runnning everything through a P.A., I'd say go ahead, and maybe get someone to do the sound. On the other hand, if the guitar player has a 50/100 watt "stack", and you have a 400 watt bass head, I think you guys don't need to be "mic'ed"...just the vocals and the drums.

[broadcaster]

I don't mind going through a PA if I can hear myself clearly in a monitor. I prefer having an amp on stage for a monitor and also sending a signal to the soundman for FOH.

The PA needs to have sufficient juice and speaker capacity to handle bass along with everything else.

[unbridled]

I'd say no. The behringer power amps generally don't have enough reserve power to handle bass notes with heavy attack. Once you hit a hard bass note, the power amp will clip and the "reserve power" won't come back fast and the entire mix will sound bad, not just the bass. Also, you gotta remember the speakers are only 12s.

I'd do without for now and once you get gigging more, buy a crossover and some powered subs.

What kind of bass amp are you running?

[atinder]

Bass amp I'm using is the new Acoustic 200 head through a Peavey BW 1x15. Not tons of power, but sounds pretty good. Any thoughts?


Thanks for all the advice so far - as usual, this forum is very helpful.

[unbridled]

If the drummer is under control, I'd just run the amp for now. I don't think you'd gain much through the PA you have and would run the risk of creating more problems. If you do decide you can't live without running through the board, a compressor is your friend (on the PA, not just your bass compressor)

[Strawfields]

You want a DI box from bass into PA and small amp as monitor if there is no 'Foldback' ( on stage monitors') but I'd only do this if you're also miking the guitar and Kick drum.

Ignore bit about mandolin http://www.soundonsound.com/sos/may0...s/qa0507_1.htm

[Strawfields]

Also

http://www.arx.com.au/FAQ_DI_boxes.htm

[Tim Armstrong]

Originally Posted by atinder

Bass amp I'm using is the new Acoustic 200 head through a Peavey BW 1x15. Not tons of power, but sounds pretty good. Any thoughts?

I'd run the amp as loud as needed, up to the point of diminishing returns, and run a line out to the PA system but only actually turn that up if needed, to augment rather than replace your amp...

Cheers, Tim

[4mal]

you don't have enough PA to even consider it IMO. If you need more volume from the bass, add speaker area - a second 1 x 15. You're only seeing about 140 watts at 8 ohm's with the Acoustic from what I've been able to read. That's pretty light. 200 at 4 ohms is better - still light for my uses but better. The additionaly speaker area will help a bunch.

If you stay with a relatively low powered head, then you might consider going to more efficient 15's.

[atinder]

You know, that brings up a related question: the 1x15 I'm using is a homebuilt job that has a Peavey BW speaker in it. It was built nicely, and works great - but I honestly don't know anything about its power handling (I acquired it as part of a trade). Is there any way to tell if it's 4 or 8 ohm? Or would it most likely be one or the other?

[robbysturgis]

It's a frequency thing, don't you know.

But seriously: If you want your bass line to push enough air directly to the ovaries in the audience, a normal PA speaker is not going to do that. First of all the PA speakers are directed at face level, to impact the ears. The bass needs to be at floor level, impacting the family jewels. Plus that is where the bass drum is driving the sound home.

plus, a sweet range speaker for vocals and acoustic guitar is not made for the deep rumbles.

If you are going for the deep sound, add a sub woofer to your PA gear, and try it that way, but the extra problem is, you can't shape the sound to match your guitar...face it, not all bass guitars are the same, so you have a volume and tone control on the guitar, but you have an equalizer on the bass amp, to shape your tone there.

your thoughts?

[Tim Armstrong]

Originally Posted by atinder

You know, that brings up a related question: the 1x15 I'm using is a homebuilt job that has a Peavey BW speaker in it. It was built nicely, and works great - but I honestly don't know anything about its power handling (I acquired it as part of a trade). Is there any way to tell if it's 4 or 8 ohm? Or would it most likely be one or the other?

First, I'd look and see if there's a label on it that says!

If there isn't, a volt-ohm meter set to read the resistance in ohms will give you an idea. If it reads 3.2 ohms, that would be a 4 ohm speaker (speaker impedance is roughly resistance x 1.25).

You can find out what the power handling is by Googling Peavey Black Widow 15. I'm sure it's considerably higher than your amp!

Cheers, Tim

[atinder]

Yeah, no label. Now for the embarrassing part: I own a meter, I just don't know how to use it for this kind of reading. What am I actually putting it on to check the impedance? (I guess it's better to ask than pretend I know what I'm talking about.)

For what it's worth, I'm thinking that the Acoustic 200 head is 200 watts at 4 ohms - so I'm better off making sure that I'm getting the power out of it by running it into a 4 ohm cab, right? Whereas if my BW cab is 8 ohms.........

[unbridled]

Put it on the leads of the speaker. If it is 4 ohms, you're pulling all you can from that head, if it is an 8 ohm speaker, you can add another 8 ohm speaker cab. 2 seperate 8 ohm cabs would be better for you situation IMO.

[hockey_head]

yes by using a 4 ohm speak you will be effectively doubling the percieved volume.
black widows i think are 200 watt program speakers which would be a good match for your amp(4 ohm speak).
also if you're using a four string bass your set up might work pretty well as is. you're not trying to amplify that lo B note which hogs a lot more power.

[4mal]

Easiest way to check the impedance is to plug a speaker cable into the cab, set the meter to ohms, scale should be 10 ohms preferrable or if it's a digital- never mind that piece... touch one probe to the indentation a the tip, pinch it into contact, touch the 'shaft' with the other probe. Chance are you'll see around 6/6.5 ohms which would be about typical for an 8 ohm driver.

IMO about the best replacement driver out there today is the Eminence Kapalite 3015*. The sensitivity on the 3015 is a little over 100 DB - not bad at all for a speaker that will go deep and loud! It seems to be real unfussy about box design as well. I have one loaded temorarily in an old Sonic can that is about 2.5 cu ft with a slot port - and it rocks in there even though the speaker design program says it wants more room and less port. Raw driver wise, that's about 2 db more output than the Black Widow at least accoriding to specs. Personally - I'd bet it is more than that. My gut feeling is that the B/W is over rated in the sensitivity department. They seem to need a bunch of power to me ...

I'm working on a 1x15 design for it that will stack under an Avatar 2x10. About 2.8 cu ft total volume, slot port design. ... and being a neo based driver - it weighs next to nothing ...

*Note: the 3015LF - a great speaker but meant for sub woofer duty not full range bass guitar. Plain old 3015 is the driver I'm using! Used in perfect condition, they pull $125 shipped. New IIRC about $175 from www.bltsound.com - Bernie is just the best guy on the planet when it comes to speakers parts. He's just gone up and over the top for me in the past customer service wise. I can't recommend him enough! I do wish he were closer though!

[bargoedboy]

most bw peavey speakers will handle 350w plus , very good speakers i have used them on and off in bands for years , good thing is blow a cone and you can unbolt it and pop in a new cone in 5 mins plus if you have the 8ohm cone buy a 4ohm one which will get more out of the amp .
as for putting it through the pa , sorry but your pa is not upto it and with your backline you will need the pa to get the vocals above the band dont swamp it with bass. i never put bass through PA unless i have a decent bi amp rig ie bass bins and crossover to top speakers . i like the sound of a bass through a big pA rig as its similar to a studio, full range and clean.
good luck .

[Ben Harmless]

That PA will be fine for vocals and keys and such, but it just doesn't have the power to push the bass into the room and still do a good job with the vocals.

As someone who's mixed shows in small bars and large festivals, I wouldn't start running bass into a system until I had about three or four times that power - minimum.

Not knocking your system, but I don't want you to blow it up, either. bargoedboy's right. You'll want a system with subs and dedicated amps for it to really work.