Musician Forum - Band Discussion Board - BandMix

John I saw your post yesterday regarding the musicians gear post. I went there back on 6/20 its so buried I don't think you noticed. If you get a chance check it out!

Thanks man, Im just trying to decide whether to just input one QSC amp for the subs, or whether I should input for two amps, Im going to set it up early sat afternoon and play with it. Im sure it will be fine, I love that DBX unit!

I would use 2. One for each cab bridged especially for the subs. For subs my experience says 2 to 3 times the program power! I know it cost more but there will be minimal distortion with more power. Thats how I have my system set up. Oh and I agree with the 75 to 80% of volumn at the amp thats the way I use them.

Haley we had an older QSC amp, its a 1300 watt amp, so I put it in the rack for our monitors, which is what we used to use it for, I had just kept it in the trailer for a spare.

So running a QSC 1450 bridged will give me somewhere between 700-900 watts power at 8 ohms for each of my subs, should open the bottom up quite a bit, I had been using one amp bridged and daisy chaining the speakers so I was pushing them into 4 ohm range, I think running them in 8 ohm will make the amp breath better.

The place we are playing has a large seperate music room so sat afternoon Im going to hook it all up and RTA the room, it wont bother anyone like when you set up and there are people at the bar.

One more question when you RTA a room so you set the curve flat, or use one of the curve settings? I had been using the D setting which has a nice happy smile, but I was told by the guy I bought the unit from to just use a flat curve for live music, and use the curves for canned music.

Did you ever play with the sub harmonic setting in the DBX unit, I actually rolled off the QSC amps at 30 hz, I may need to cut those filters back off if I kick in the Sub Harmonics?

Just curious of your thoughts on this since youve used yours a lot.

Thanks

jw123 wrote:Haley we had an older QSC amp, its a 1300 watt amp, so I put it in the rack for our monitors, which is what we used to use it for, I had just kept it in the trailer for a spare.

So running a QSC 1450 bridged will give me somewhere between 700-900 watts power at 8 ohms for each of my subs, should open the bottom up quite a bit, I had been using one amp bridged and daisy chaining the speakers so I was pushing them into 4 ohm range, I think running them in 8 ohm will make the amp breath better.

The place we are playing has a large seperate music room so sat afternoon Im going to hook it all up and RTA the room, it wont bother anyone like when you set up and there are people at the bar.

One more question when you RTA a room so you set the curve flat, or use one of the curve settings? I had been using the D setting which has a nice happy smile, but I was told by the guy I bought the unit from to just use a flat curve for live music, and use the curves for canned music.

Did you ever play with the sub harmonic setting in the DBX unit, I actually rolled off the QSC amps at 30 hz, I may need to cut those filters back off if I kick in the Sub Harmonics?

Just curious of your thoughts on this since youve used yours a lot.

Thanks

John I use the D curve because its a little heavier on the bottom end and gives the bass guitar and kick drum a little more thump. I wouldn't use a flat curve I totally disagree with that. I do not use the Sub harmonic on the driverack I don't remember why. I am using 2 of those same 1450's one for each sub bridged. I also have a QSC PLX 3602 that I run the top speakers with. Are you using a Sonic Maximizer it gives me a little more adjustment. When you auto e.q. do you name and save the settings? I find they come in very handy in a pinch.

Yeah Haley I have most of the venues we have played saved, but since iM changing up the subs I want to rerun this room this weekend.

we are running the two QSCs into the subs, around 900 watts each, so 1800 in the subs, then Im using a Yamaha 7000 series into my 2x15 tops, these cabs are 4 ohm, so we are driving each one with roughly 1100 watts a side. So the FOH mains are getting around 4000 watts.

Then probably around 1000 watts into our monitors, with the older 1300 QSC.

I think I will continue to set them up with the curve, it has worked well in the past, like you we wanted a little more punch on the low end, than a flat curve, and when I used to use eq's we always notched the mids anyway thru the years.

Gentle suggestion from past experience:
When we ran subs, we found that careful use of the subsonic filter resulted in more clean chest thumping kick drum and less stage rumble, sucking up precious amplifier headroom. We found the -3db point on the subs and used that as our LF cutoff point. With these JBLs it was 40hz:
https://docs.google.com/viewer?a=v&q=ca ... sw0C9RGJMw

YMMV

Good luck with your gig JW!

Johnny we left the filter at 30hz on the sub amps, you can set it at 50 or 30.

I have to say, we played with it sat afternoon and with the added power on the subs, this system is really romping!

We turned it up with canned music, way way higher than we would for a gig and it didnt break up in the lows at all, my bassist uses a 5 string and we ran him thru it and I had him really hammer the low b into the system and it was crystal clear, no breakup at all.

Haley if you read this, we did run the curve on the eq parameters and I love it.

Sat night we had the kick and snare sounding as tight as ever, clear.

Just really sounded good, during the first set before the crowd went crazy, my bassist and I went to the back of the room with out wireless's and it just sounded like a cd player.

I think we finally got that sytem performing to its full potential. And oh yeah Haley I ran the top amp at 50% and the subs at 60% on the gain controls, it just sounded so smooth the transition between the lows and mids.

Thanks guys for all the responses to this, Im one happy camper this morning.

Congrats John don't it feel good! I get to use my system this Sat again as Barry is on vacation.

Well we had one of those gigs sat night, classic Aint Yo Mama gig!

I made a little video from behind me, you couldnt even see us from the front cause so many people packed it plus we set the drums up front so all these gals were going behind him and dancing, if I can figure out how to get the video on here I will put up a thread about it.