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lgc
Jan-28-2009, 3:37pm
Are these an applicable piece of equipment for a condenser mic setup? Does anyone use them and if so what kind of results have you found. Are there any brands or models worth checking out? Would this be the kind of thing you'd bring to gigs with you and plug into the PA. I'm not very informed.

TonyP
Jan-28-2009, 3:59pm
I use dbx DriveRack 260, and it's part of the PA we use. I've found it very necessary for playing loud and using condensers. There are several different unit's in the dbx line that have a feedback suppressor as part of it's arsenal. I like the 260 for the computer interface that helps me see better what's going on. These kinds of units are always part of signal chain for the whole system, not just one mic.
There are several different brands but for me, it's either dbx, or Sabine. From what I've seen in pro's racks and talking to them, stuff like the Behringer, while less expensive, doesn't work. You will see dbx's in the higher end racks along with Sabine's.

Dave Reiner
Jan-28-2009, 4:03pm
Short answer -- Behringer = cr@p, Sabine = great!, dbx has good rep but I haven't used it.

We use a Sabine FBX 2400 - one channel (12 parametric, automatic bands) on a central Shure KSM27 mic (we have also used it on condensors, with good results) and one channel on the monitor mix. Gives us more headroom, and works very well. Can also combine the two channels if needed.

Dave

steve V. johnson
Jan-28-2009, 5:15pm
Tony, if you hadn't replied to this I was gonna go lookin' for you to point you here. LOL!!!

After all the discussions of this stuff that have been here... whoooee.

But, sure as a cadaver dog, you found it! Hurray! And well done.

lgc, you have found The Man. Tony has studied and worked to get this stuff right and he's
the one who knows how to use the dbx and it's feedback suppression. And for my $.02, the
dbx is certainly the pick of the lot.

stv

Doug Edwards
Jan-28-2009, 6:16pm
Good and bad luck with the Sabine FBX solo. The device worked great but only lasted a year or so. I've gone through two now. The first one was send back to the factory, who in turn declared it fried. They were happy to replace it for $290. The second one, purchased through the factory, quit after a year. I have not done any thing with it. Perhaps their rack model does better.

The Behringer Shark was junk from the git go.

Tbone
Jan-28-2009, 6:26pm
Do you guys still use an EQ if you're using the feedback supressor? How does it fit into the signal chain?

Right now, I'm using a 16 track Allen&Heath Mixwizard, with a dbx gate/limiter/compressor -> dbx 2 channel 31 band eq into the main inserts on my board, then out to an amp, to the mains. Powered monitors from the 2 monitor sends. Would I need a seperate feedback buster for the mains and monitors?

TonyP
Jan-28-2009, 6:56pm
You know me too well Steve, one trick pony goin' in circles :)

I think I'm on year 3 of the 260 and it's been wonderful and performed it's duty every time. Sorry to hear about that Doug. I think things are much safer in a rack, and who knows what the difference between the two units is.

I use the ch. eq. for each instrument/voice, and then have used the auto eq. to get a baseline eq. on the speakers. From there, depending on the venue, and how loud, I run the FB wizard and see if it got 'em all before it runs out of notches. If not, depending on the graph showing where it dropped the auto notches, and how wide they are, and how close together they are, I'll either use the 31 bd eq. or notch filters to "help" out the FB. Then run the wizard again, and that usually does it.

What's cool is ALL of this stuff I can do with the laptop through the 260. It actually has, depending on how many inputs/outputs I'm using has a possibility of 8 31bd eq's, 6 notch filters, and 6 parametric eq's! All in one rack space, and it can do a ton of other stuff like auto eq.(which I've now learned how to use properly, and after checking with the pro analyzer SmaarLive, is dead on! That's remarkable in itself)

And because it can be run dual mono, the monitor, and mains are separate in their eq adjustments, and FB's. I have only run IEM's for live monitor so far so that doesn't require the FB. But, I've got some Mackie SRM 150's and have been waiting for the right time to try them out as monitors. So, when I set them up, I'll use the separate program I've got that runs the FB on the mains, then on the monitors. Would seem the only logical thing to do. But, I've only did a practice run in the back yard with it. Next time we do an outdoor, or quiet concert gig, I'm going to try the 150's. Unfortunately I got 'em after the weather got cold.

steve V. johnson
Jan-28-2009, 7:50pm
Tony sez he's, "...one trick pony goin' in circles ..."

I can't affirm that one, mate, not after all I've learned from you!

Carry on... :cool:

The dbx 260 manuals are on the dbx website here:

http://www.dbxpro.com/260/260.htm

and I've found reading the manual to be really useful in understanding the thing.

As you can tell from what Tony says, this is a deep device, but it can also be very simply used.

stv

TonyP
Jan-28-2009, 8:08pm
Sorry Tbone, I kinda lost track.
The mixer Lch> ch 1 input DR #1 output> input of Mackie 450 powered speaker, then daisy chained to the other speaker.
mixer Rch > ch2 input DR #3 output > input of headphone amp for IEM's, or Mackie 150's for monitors.

BTW limiters, compressors, gates are built into the DR, and can be used and configured through the laptop too. The DR is called a speaker management system, and that pretty well describes it.

GVD
Jan-28-2009, 8:12pm
I'm here to tell you that Tony knows what he's talking about. After doing extensive research I decided to go with the 260 Driverack. Tony was kind enough to offer advice and baseline set up parameters which helped immensely. Thanks again Tony!

We run a pretty similar setup to Tony with a few exceptions. 2 LDC's and 1 SM57 (for the banjo player) into a Mackie 1402 mixer then through the Driverack with one channel feeding the SRM 450 mains and the other into the SRM 150 monitors.

This rig works like a charm. I'm pretty new to all this and was pretty much forced into learning sound reinforcement by default. Thanks to the Driverack people around here think I'm a sound guru now. If they only knew! We played a crowded LOUD bar a couple of weeks ago and the sound was perfect. A guy I know from out of state happened to be in town and came by the show. He runs FOH for a lot of big festivals out west and I asked him if he would help out if we needed it. He came up after the first set and said "Man when I first saw those LDC's with the monitors right behind them I thought for sure you were going to have big time feedback. You may want to tweak the EQ just a tad on one of the mics but other than that it's perfect."

Not one peep of feeback all night. There were a bunch of other musicians in the audience and to a person they all said it sounded great and couldn't believe the lack of feedback. A couple of them who have been at this game a lot longer than me came up and started taking pictures of our set up during breaks and asking all kinds of questions.

I agree the Behringer Shark is not up to the task but I've never tried a Sabine. The 260 Driverack is the real deal IMO.
GVD

TonyP
Jan-29-2009, 11:25am
aw shucks, twern't nuthin you guys wouldn't do for the rest of us.......you are too kind guys. With GVD I got scared because this machine is so deep, and unlike Steve, the manual make little sense to me. There are others on the dbx forum that feel the same way about the manual. I'm glad you got it to work for you GVD.

I have a process where we get everything but the mains going(you can "cut" them with buttons on the front of the DR) and just do a sound check with our IEM's in. This way I can get true levels before I run the FB. I've learned the hard way don't rely on doing some kind of check individually, it's never right. Do a song that goes through all the breaks and it covers it all, vocals and instruments and ask, everybody ok?. Then everybody unplug the IEM's and go away while I run the FB wizard.

What's funny is it always flips the audience out because they can't hear the PA(which makes our bass player crazy as they are always looking at him and pointing to the their own ears, "can't hear?!?). Then they are usually the ones that hang around when I run the FB and I hear the comments, "check this out....". As I run up the volume and it starts to feedback and you hear the ooooo..op! as the FB kills it. Truly magic.

The really bad thing is though everybody thinks then I can make up for bad mic technique and weak playing......NOT! It's no wonder nobody ever wants to do the sound. You can go from wizard to jerk in a heartbeat. No matter how many boxes I get, that part never goes away.

GVD
Jan-29-2009, 4:33pm
The really bad thing is though everybody thinks then I can make up for bad mic technique and weak playing......NOT!

Dude don't even get me started!!! ;)

GVD

steve V. johnson
Jan-29-2009, 4:43pm
Ahhh, yep. Fer shure.

stv