1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

upgrading PA system (sorry for the long post!)

Discussion in 'Live Sound [BG]' started by morgansterne, Nov 26, 2012.

  1. morgansterne

    morgansterne Geek U.S.A.

    Oct 25, 2011
    Cleveland Ohio
    I'm in a cover band that runs our own sound. We've been using a Behringer pmp6000 mixer for mains and I recently bought a mackie FR800 to upgrade our old monitor amp. We have 3 yamaha 12" monitors and 2 JBL tr125 mains. Volume is pretty well maxed out on the lead vocal and main fader to carry over the drums (mic on kick, toms are electronic).
    After sticking a mic out in the room to record set 2 and 3 of our last gig, I'm hearing
    1) a need for vocal compression. the lead vocals didn't cut thru when he goes into the low register. We're all good singers but our lead guitarist has pretty poor mic technique.
    2) a need for compression on acoustic guitar
    3) you'll probably suggest we need a subwoofer, but we're usually turning the low end down on our PA, so I'm not convinced of that.

    PA setup options:

    1) use channel inserts and buy rackmount compressor units for the four vocal channels.

    2) I have a yamaha aw4416 recorder/digital mixer with built in effects including compression on every channel. It's only got eight inputs though, so we'd have to have a submixer (probably my allen and heath zed10 that I bought for recording chores) going into it. Also we'd have to use my mackie amp for the mains (and revert to our old monitor amp which still works).
    Wattage rating wise it's a little confusing -- the Behr says it's 300 watts @ 8 ohms, the mackie is 140 watts at 8 ohms. BUT the Behr rating is 1% THD, the mackie rating is for 0.01% THD. (A little net research reveals this to be EIA rating vs. FTC rating.)
    there's really no great way for me to test in advance whether or not we can switch to unpowered mixer + mackie amp. I think a little drop in volume with the mackie might be ok considering we'd be adding compression on the vocals (and maybe the main mix even?) and we'd apparently be lowering our total harmonic distortion (unless we have to turn up all the gains to compensate for lower power output!)
    NO knee jerk Berhinger bashing please. We've been using this powered mixer for about two years and at least forty gigs.
  2. modulusman

    modulusman Banned

    Jan 18, 2004
    I'm not going to tell you to get a subwoofer. You need a whole new PA. Seriously the reason you can't hear your vocals is your speakers are 15 years old and mainly designed for just vocals. Your power amps are not powerful enough for a kick drum. It will eat up all your available headroom. Time to punt and start over.
  3. lowfreq33


    Jan 27, 2010
    Endorsing Artist: Genz Benz Amplification
    Well, for zero dollars you could use the Yamaha mixer for the compression on vocals and acoustic. Use the main L/R outputs into 2 channels on the Behringer for vocals, and run the acoustic out of an aux into a channel on the Behringer. It's a little janky, but it's using what you've got.

    As for the suggestion for upgrading your mains... Not enough information for me to say. No idea how loud your mix is, what kind of venues, etc. Modulusman and I tend to disagree on PA threads, his idea of sufficient power/speakers is generally higher than mine, and I'm not going to debate it again, my guess is we have different requirements based on genre and mixing styles. I suppose you could do with better mains, those jbl's weren't that great when they were new, and PA speakers have come a long way since they came out. But if your overall volume is fine and you just need more out of a couple of things, try lowering all the other faders a bit and raising the master. This will buy you a couple db more headroom for the vocals, which are honestly the most important thing.
  4. walterw

    walterw Supportive Fender Gold Supporting Member Commercial User

    Feb 20, 2009
    i agree, but if you gotta make this stuff work somehow, a sub (especially a powered sub) is the temporary answer.

    it'll handle the low end from the drums and whatnot, which will let you take that low end totally out of the shoestring top boxes, which will let them be a little louder and clearer.

    compressing everything isn't the answer, it'll just make it all that much quieter.
  5. Don't compress everything, but compressing the lead vocals can be good. If they get too quiet because of it, just use the output (or "makeup") gain to bring the overall level back to normal.

    Ideally, compression will be transparent and unnoticed, and will simply reduce the peaks while bringing up the quiet parts to even out the overall level.
  6. Stumbo

    Stumbo Wherever you go, there you are. Commercial User

    Feb 11, 2008
    Intergalactic Mind Space
    Song Surgeon sofware rep.
    1. Video the guitarist at the gig so he can see and correct his "poor" mic technique. No cash out of pocket to compensate for laziness.

    2. +1 to adding a powered sub to help out your mains.

    3. No way to know about your extra equipment and how it works unless you take it out on a gig. Maybe set it up for rehearsal and give it a chance to perform, at least in that environment.

    4. Go wireless your for bass so you can go FOH since you're running sound. Best way to check things out, especially after sound check when the venue fills up and off and on during the gig.

    5. Maybe your whole band it too loud? Something you can check FOH from the back of the room.
  7. walterw

    walterw Supportive Fender Gold Supporting Member Commercial User

    Feb 20, 2009
    exception noted, and concurred with AOK.
  8. agreed. new pa system required. 225w of power is not much these days. once you step up to like 500w or even 1000w, it will fix the majority of your volume issues in regards to things not cutting through and give you the head room you require.

    compression as people have said, is a means to "compress" sudden spikes in volume in order to protect your equipment and peoples ears and/or make the incoming signal from a mic/instrument more even sounding. IMO if you are looking fora good replacement console that gives you this and not looking to lug around more outboard equipment, and have an ipad take a look at a MACKIE DL1608, its a fantastic mixer and reasonably priced.
  9. Regarding power amps, I use a little rule of thumb that has worked quite well for me over the years: The USEABLE power output of the amp is HALF the rated output at reasonable THD levels (<.1%). This gives you enough headroom for most situations that are likely to occur. For instance, the Peavey CS800X that powers our mains is rated at 400 watts/channel at 4 ohms at 0.03% THD. So I treat it as a 200W/channel amp. Now the fact that it rarely has to put out even 50 watts/channel continuously means that it runs very cool, fan never hits high speed, and clipping is never an issue. The real output of that Behringer is quite a bit less using reasonable THD levels, which is why I suspect they don't release those specs. I'd guess (using the half rule above) that the actual power output is closer to 250 watts/channel. Not bad for two mains. The Mackie might be useful for a monitor or two if your stage volume is low enough and you are running just vocals through it.
    Compression on vocals is something I find is usually needed, even if set to only reduce an inadvertently loud note or two to prevent input clipping.
  10. morgansterne

    morgansterne Geek U.S.A.

    Oct 25, 2011
    Cleveland Ohio
    I only yesterday got around to checking out the specs on our JBL mains and was a little dismayed. the singer figured that they are JBL's and thus they must be awesome, I guess.

    the guitarist and I recently both got wireless systems, so we've been checking out front more often lately.

    Our main fader is pretty well maxed out -- not all the way at the top but near it.

    Really the whole band can't turn down. According to the recording I made of our last show, the hi hat is the loudest thing in the whole band and it's not mic'ed. (this was an unusual shaped, all brick and concrete room, tho.) We've all talked to the drummer about being quieter and threatened to make him play an all electronic set.

    thanks for all the suggestions everyone.
  11. Stumbo

    Stumbo Wherever you go, there you are. Commercial User

    Feb 11, 2008
    Intergalactic Mind Space
    Song Surgeon sofware rep.
    IME, the drummer controls the volume.

    Louder the drummer, louder the band. Best drummers in my bands over the years can play at any volume with acoustic drums. No need to pound away like their life depended on it.

    +1 to all electronic drums. Problem solved. No more discussing, asking, begging him to change. Seems like he won't, can't, doesn't care. Ask him, "How would the band sound if everyone played louder and without considering the band's overall sound?"

    IMO, if you get all electronic drums first, then you will be able to make better judgements about what your PA really needs. Maybe you don't need as much as you think.

    Put the electronic drums (except for the kick) into a small mixer of their own and then run them off of one channel of the main mixer. Maybe that will help. I've seen that done before with excellent results.
  12. morgansterne

    morgansterne Geek U.S.A.

    Oct 25, 2011
    Cleveland Ohio
    two gigs this weekend so we're going to try using a sub with the singer's little pa head powering it. It's 800 watts in bridge mode so with the pmp6000's crossover engaged we should be adding a little headroom to things!
  13. Vinny D

    Vinny D

    Jan 9, 2007
    Warwick, RI
    How about hiring someone that actually knows what they are doing and let them go through your system for you?
    This way they can hear your band and tell you what your best option(s) may be.
    I would rather throw $1-200 away on having a pro come and setup/run your system then buying more items that may just end being used as paperweights.
    The more that your try to patch together a workable PA out of what you currently have and how you are running it may just end up giving you more problems with more areas to have issues with.
  14. morgansterne

    morgansterne Geek U.S.A.

    Oct 25, 2011
    Cleveland Ohio
    Anyway just wanted to update, for anyone having similar problems in the future. Friday night we hooked up an extra little PA head to a 15" 500w cab to have a sub with its own power source, engaging the board's crossover. Nice improvement to the sound once we adjusted EQ for it.

    Saturday night, same setup, but with the guitarist getting his own monitor mix. Our board has two aux sends so it's only two monitor mixes for all five of us. It was actually quite fun just to watch him come right up to eat the mic, and then back off the instant he opened his mouth cuz his vocals were cranked up in his monitor, (and backed off in everyone else's) .;)

    I personally hate having my vocals louder than everyone else's in my monitor mix, but apparently that's what he needed to perform the right way . . . ! :D