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View Full Version : Had bad trouble with my sound system last night!



jim_n_virginia
Aug-12-2007, 7:12am
We had what should have been an easy gig. It was an outside block party with plenty of room to set up. Since they were only expecting 60-70 people I brought my Bose system which I have been using almost exclusively since I got it 4 months ago.

We did the sound check and the instruments (mandolin, upright bass, guitar and fiddle) sounded OK. I couldn't get much volume on them (my first hint something was wrong because usually outside you can get tons of volume) but was passably loud enough. The problem I had was with the vocals. They sounded terrible. Like static when you spoke or sang into a mic. I double checked my wires. I switched the mics to differnt channels. Thinking maybe somehow two mics went bad or something I tried another mic and still the same problem. It was MOST distressing. I couldn't enjoy myself at all.

After our first set I didn't take a break and double checked my wires. Like I said the instruments sounded fine so I switched the mics to the channels the instruments were running through and STILL got the same problem I even switched the XLR cables on the two mics. NOTHING helped. The sound was breaking up and had a loud buzz at the end of whatever you said. I was really stressed. After I triple checked the wires, system and the mics I started looking at the power source.

We were set up in the street. I had to run power from a house. I knew it was going to be a fairly long run (75') so I bought brand new heavy duty 12 gauge electric cords.
Thinking maybe there was too much of a power drop off I intially had two 50' 12gauge cords. I took one out and REALLY stretched and used a 25' footer so the minimum I had was a 75' run with the second fattest electrical cord you can buy (they make a 10 gauge)

I then took out the 6 way outlet I was using to run lights (two little 40watt bell lights), sound sytem and mixer power and used a direct three way plug. When this STILL didn't work I resigned myself (we had done 2 sets by then and only had one more to go) that this was as good as it was going to get. I guess the people didn't notice that much. We got a lot of compliments but also a lot of requests to "turn it up"

And the most important part we still got paid. Still I was stressed to the max because we are a good band and we didn't sound as good as we could have and this was a pretty high paying gig and I really want the client to get their money's worth. To make up a little we stayed a little later and played an extra 45 minutes which they seemed to really appreciate. I CANNOT let this happen to me again! I am not so experienced with sound reinforcement. I've only been running my own sound a couple of years and not so much because half the places we play had their own sound.

Does anybody have any idea what could have went wrong? Do you think that it was a power drop off from running 75'? Anybody got any experience from having to run long distance to get power? I am going to set up the same exact set up today out in the backyard using the same cords and see. I cannot let this happen to me again! Again the vocals had a crackiling sound, almost like when you have a blown speaker, you know that buzzing sound only when you sing or speak otherwise quiet, in other words it's not a constant buzzing. Also the power seemed like it was crackling off and on.

If its the last thing I do I am going to find out waht happened last night. If anyone has any ideas of tips I sure would appreciate it!

Tim2723
Aug-12-2007, 7:37am
Jim, the first thing I though was a blown speaker. Power supply problems tend to affect everything equally in my experience. Get the system assembled and try to replicate the condition.

Ken Sager
Aug-12-2007, 9:46am
Could the gain on the microphones been all the way up? Turning up the gain and turning down the volume will distort that way (classic overdrive). If the instruments sounded fine through the same channel where a vocal mic was distorting then I'd look at gains, mics, or mic cables.

As Tim suggested above, I'd set it up again and try to duplicate the problem, allowing you more time and less stress to figure out what was happening.

Good luck,
Ken

theBlood
Aug-12-2007, 11:06am
I understand and empathize with your frustration. There's really nothing like the feeling of having a problem with your sound system and being compelled to proceed with the gig anyway. Not exactly conducive to the best playing.


For what its worth, I try to have some kind of backup for nearly every piece I bring to a gig: cables, speakers, preamps,etc.. out of fear for just what you're describing.

From what you've said, I would try alternate cables for the mic and the other associated connectors. Cables are something that can partially work, or work intermittently. Usually a mic or mixer that's been in use won't suddenly go bad.

Also, even though the Bose has a useful, though limited, little mixer, (IMO) it still would be wise to have a backup inexpensive mixer for just such problems, in addition to adding other players...


John

sbarnes
Aug-12-2007, 11:45am
we try to never run the lights and other equipment on the same circuit.....
usually means buzz city but for the entire system.....not just the vocals?

mandolooter
Aug-12-2007, 11:52am
what Ken said is a good place to start. With the Bose systems the active EQ basically gives it its sound and without it the sound is miserable. I'd be very curious as to what ya find out when ya re-test it.

steve in tampa
Aug-12-2007, 4:20pm
Check the pre sets on inputs 1 and 2. Match them to the mics or put them on 00 for a mixer feed.

jim_n_virginia
Aug-13-2007, 1:14am
Check the pre sets on inputs 1 and 2. Match them to the mics or put them on 00 for a mixer feed.
I put the system together this morning and gave it some serious thought before I had to leave for a friends funeral and then a bunch of meeting the rest of the day, didn't get back until the evening so I will plug in everything first thing in the morning and try and recreate everything as I cannot have this happen again.

One of the things I did notice when I pulled the bottom of the system out is I didn't have the presets (I have the old presets) on 01 for the Shure SM-58's of which we were using they were set on 00 for some reason. I have vocals into channel 1&2 and bothe presets were 00, I know I set them to 01 last gig.

Could this be the cause of my distortion? I can't hardly believe it could be. I'll plug it in tomorrow and see. I have also posted on the Bose board and they are working with me on that.

I've got to get to the bottom of this as I have used this system half dozen times beautifully since I first got it. When it is working right the sound is the most natural I have ever heard out of speakers.

Thanks for the other ideas and suggestion I will check them all out and see it that is what was wrong.

steve in tampa
Aug-13-2007, 3:09am
A wrong pre set and phantom power on was once a short sound problem for me with a dynamic mic.

Timbofood
Aug-13-2007, 7:35am
This sounds very unlikely but could the pots be dirty? System seems too new for that to be a problem but our old Peavey XR600 started to get a case of the "scratchy's" after cleaning everything (slides, knobs, pots, and all) it was back to sounding like new. I guess that means scraping 25 years of crud off some things is good. I agree with the separate line for lights theory, I have heard problems with that before too.
My band just did a corporate party for about 150 outside and we opted not to use any sound re-enforcement at all. Those that wanted to hear came close those that wanted to talk ,etc. stayed back. When being an organic jukebox I like being organic, It makes the escape easier. Nothing big to dismantle and load...Case instruments up and go!

jim_n_virginia
Aug-13-2007, 9:07am
In looking at my notes for suggested hook up from bose I noticed that I was supposed to connect the 3rd and 4th channel on the Bose system to the left and right Main input on my mixer. I only had channel 4 going into one side of the mixer, the left I think.

Could have this been my problem? I could not recreate my setup from Sat night, of course everything works FINE at home!

Also I had my presets wrong. I got a question in at the Bose site to see it that had anything to do with it. It shouldn't have caused all the distortion I had.

Thanks for all the suggestions and tips so far.

Big Joe
Aug-13-2007, 10:17am
I'm not familiar with the Bose system, but the location outside can be an issue also. If there are power lines nearby, power transformers, radio or cell towers nearby, any of these can cause issues...particularly with inexpensive or poorly shielded cables or cords. Whether it is the cord from the mic to the mixer or to the power amp or to the speaker, any thing in the system that is poorly shielded may cause noise when used near any high power line.

jim_n_virginia
Aug-13-2007, 10:33am
Joe we were outside with powerlines all over the place. And I did have to run a cord 75'

but most all my instrument and mics cords are Monster brand cords, should be well shielded for the cost of them.

hmmmm http://www.mandolincafe.net/iB_html/non-cgi/emoticons/rock.gif

allenhopkins
Aug-13-2007, 10:38am
Sounds to me like a problem with your power supply. If you can't re-create it at home, the operative variable may be the "juice" that was powering your system. It was a block party, probably your extension cord was plugged into someone's house or garage, who knows what else might have been on that circuit, or what the condition of his house wiring was. You were getting low volume, which may also have indicated that the amp wasn't receiving enough power.

Hard to tell what might have happened, but if the only way you can replicate the situation is to go back and plug the PA into the same guy's house, there may be nothing wrong with the Bose.

TonyP
Aug-13-2007, 11:03am
It would be interesting to know what kind of outlet you were coming off of.

We played in a little gazebo that the people there had obviously made. They also wired it. My workhorse 4033, which had NEVER given me a bit of trouble just refused to work. Something in the way it was wired, as when we went home, and ever since, it's worked just fine. The rest of the PA seemed to function a little weird, but we got through. It's one of the reasons I use a Furman now, #1 you can see at a glance exactly how much voltage you have, and it's supposed to tell you if there's ground faults etc. and protect the sys if there's problem.
Also, I've noticed, everytime we are playing someplace when it's hot, and the sun goes down, the humidity goes up. I know this because all the instruments start changing tune. Well if that's not enough all the sudden we start having feedback probs.. This last time my girlfriend was in the audience and she came up and asked could we turn down as we were now blasting. I would have to check with my sound tweek buddy, but it would seem that the higher the humidity, the more 'coupling' or efficiency and more volume. I bring this up, because most problems are not usually just one thing, but several.
It really sounds like more than one button got pushed on the mixer too. I've had that happen. Almost like grimlins. Find pre's maxxed, contour buttons pushed on the speakers, all kinda stuff. Don't know if it just happens in teardown or what. But all those things have cause complete havoc until I've found them and reset them.

steve in tampa
Aug-13-2007, 1:27pm
Just looking at my system, and the correct pre set for a SM 58 is "14" .Don't understimate the power of these presets. They are very specific.