PA sounded weak and thin last night

[ScreaminSaint1]

Without going into a whole lot of detail, my band has played a few gigs in the last month or so with really good sound thru the pa. Last night we played a gig and i think all we changed was take out the 18" sub and run another monitor instead.

 

I use an Ipod to get the board up and running. It sounded fine until we started hooking up all of the instruments then for some strange reason, the whole PA sounded like an AM radio. No lows and all highs. almost sounded like something was blown. Im not sure if something happened to the power amp. The monitors sounded fine. It almost sounded like the mains were out of phase/almost blown.

 

Anything to look into here?

[trevcda]

Polarity of the speakers? Polarity at the amp? Did you lower your cross over point on your highs to compensate for the removal of the sub?

[ScreaminSaint1]

i do know that my monitor had issues and i think it was due to a bad cord. i think it had a short in it. it had a splice in it, electrical taped up. I jiggled it while holding my guitar and got a small shock. Come to think of it, i don't remember having that problem until we hooked up the monitors.

[agedhorse]

Good grief, get it fixed. Wow.

[RoadRanger]

I jiggled it while holding my guitar and got a small shock.

If you're expecting to die of old age you might want to develop the habit of never touching any cords you don't have to while grounded through your guitar strings . Don't even touch the speaker cord of your own amp. It's OK to plug your cable into your guitar but other than that put the guitar down first.

[abzurd]

Throw the cord away or cut it off where it's cut and put the plug there!

[Vinny D]

 

Last night we played a gig and i think all we changed was take out the 18" sub and run another monitor instead.

 

 

Why take out the sub? that will make you sound thin right there.

[RoadRanger]

Actually sounds like the amp freaked out when shorted and blew your HF drivers with ultrasonic square waves . What amp was it?

[agedhorse]

Actually sounds like the amp freaked out when shorted and blew your HF drivers with ultrasonic square waves . What amp was it?

 

"WAS" is the operable word

[ScreaminSaint1]

 

Why take out the sub? that will make you sound thin right there.

 

 

You missed the point. It was FINE when we hooked the mains up and ran a soundcheck on those BEFORE we did monitors.

 

 

Something got screwed up later. For small gigs, we don't even mic the drums so there's very little need for the 18" sub. We run a peavey 900w power amp and a behringer 1500w amp. the Peavey was running the mains. We don't get stupid loud, we have a reasonable stage volume and set the mains (vox and mic'ed guitars and bass) accordingly.

 

The stage and monitors sounded great, just something happened with the mains that made it sound like a tin can.

[RoadRanger]

I misread your original post - I thought you said no lows and no highs. If just the lows went away you probably blew your LF drivers by putting to much bass into them - that's why we use subs to offload the bass from the mains.

[ScreaminSaint1]

No problem.

 

We don't get too crazy with the bass to begin with. we normally use one side of the peavey to run mains (two peavey 2x12 towers) and the 18" peavey sub. The behringer (which is weak compared to the peavey) is used for monitors. Most of the time the master volume on the amps isn't much past noon. (but i was always told to run the amps full throttle, even though the drummer, who owns them doesn't)

 

I guess i won't really find the problem until next practice with the full gig. everything is still in the trailer.

 

It was just weird that everything was fine when we just had the mains going. I wonder if something went wrong with the board too. It's a Crate 20+ channel board. Some of the sliders are getting scratchy.

[Unalaska]

Hmm, the peavey dual 12 (circa 82) and the sub off 1 channel? or is there a crossover involved? The dual 12 with the aluminum sides has a piezo HF driver. Could that have failed?

 

If you are using a crossover before the peavey amp and just "didn't use a sub" then the mid/highs would sound a little thin. But it could be that this cable cause the amp to freak a little and take out the HF drivers before giving up. Sounds like a mess...

[jwlussow]

If you took the sub out of the pic, did you also remove the crossover?

[ScreaminSaint1]

To be honest, i don't think we are even using an outboard crossover. For sure i know we are using a feedback destroyer, 15 band eq and compresser/limiter in a rack. It's a pretty basic system.

 

I'm not the guy in charge of the board and PA, my drummer is. I have looked around and it looks like we are running the PV215 towers, but i think they may be 12's. He knows more about it that i do.

 

I just thought i'd throw it all out there and get some ideas.

 

Thanks.

[Unalaska]

this post makes my head hurt. I'm glad it doesn't hurt my ears though.

 

Peavey really hasn't made a dual 12 since the international series and that was what I thought you meant. The PV215 is a newer box, low end dual 15 that is somewhere on par with the JRX225 (w're splitting hairs to go more in depth on the quality here). I see that many times a band "sounds good" if they can feel the low end and have a sense of loudness coming out the speakers overall. Getting out front and really listening to balance, the character of the sound and a feel for how the mix is put together is the most important aspect of providing a good listening/entertainment experience. Obviously having a dedicated person out front can really help (sometimes not!) but many bands mix from stage and it takes a really dedicated person to be able to handle both.

[ScreaminSaint1]

That's our problem too, the guy who's supposed to be out front is sitting at the mixer wearing headphones. Every time we get a decent mix out front, he puts his headphones on, plugs into the board and turns the singer up way too loud (he's also the singer's brother in law) As far as the video goes, the sound was great until he touched the board. He's pretty much done...

 

The drummer and i know when it "sounds" good, regardless of "feeling". All im trying to say is that it sounded great in front when we had the ipod going (primarily to set the eq to the room and get overall volume for the mains set) but something went to crap when everything else got turned on. It sounded nice and full for what we were running. We didn't get that loud either. just turned the mains up to rise just above stage volume.

 

It's really hard for me to explain here but i thought i'd give it a shot.

 

Ill let you know if i find something out. Like i said, im the lead guitarist, not a sound man. I just do what i can to get by.

[Unalaska]

You've got someone mixing with headphones on out front. That's a tough gig! I don't know how many times I see younger unexperienced guys using cans thru the show, what possible balancing can they do?? Cans are great for listening to a solitary input, if something is buzzing/crackling or sounding off. Because of the SPL in the room there is NO way to get a mix with them on.

[agedhorse]

A basic system would be one WITH a crossover and WITHOUT a comp, limiter, eq, etc. Crossover is more basic.

[Phil Clark]

 

...all we changed was take out the 18" sub and run another monitor instead. I use an Ipod to get the board up and running. It sounded fine until we started hooking up all of the instruments...

 

 

Ok. If your iPod is set up with Mp3's then you might not notice a difference in the sound without the Sub since the compression of many Mps's is such that it kills much of the bass. So it might have sounded just a little bit thinner, but not too bad. Then when you go to play, you would REALLY notice the difference. Loosing the Sub and not adjusting for it in any way is your most likely problem.

[ScreaminSaint1]

 

You've got someone mixing with headphones on out front. That's a tough gig! Because of the SPL in the room there is NO way to get a mix with them on.

 

 

Yeah, he's pretty much fired. He told me he does it so he can hear the singer better. Well, our singer sucks and if he can't hear him good thru the phones, he turns him up, meaning he's WAY too loud in the mains.

 

Me n the drummer were pissing him off since we kept "fixing" what he messed up.

 

I talked to my drummer last night and we are using Peavey PV215's for the mains. I was told they have internal crossovers so there's no need for an outboard one. He may have had the low cut on the power amp on. We talked about that and he said it was set right.

 

It will be a while before we gig again so hopefully we can work out a few more bugs before then.

 

Thanks for the input.

[Unalaska]

The crossover in the PV215's is between the 15's and 1" horn, nothing to do with the sub. The Sub crossover in the sub ONLY deals with the sub and the PV215's still get full range signal. This might sound good except those poor 15's can't do what the sub can so they eat up the power and don't reproduce the mid/highs near as well. It's wasted energy basically since the sub will do the same better, clearer and louded.

 

A simple rack-mount x-over is what you need. Stereo or mono it doesn't really matter. I'd bridge the PV900 on the subs (450 per sub) and run the EP1500 stereo to the tops (450 per top). Hope that helps...