Custom speaker xover setting

j.rahl

Driverack pro PA.
How do I take the settings I have for a speaker and translate that in the xover section for a custom speaker. For example do I use BW18 or LR24 and how do I know? We are using a custom biamp and the low are MTX speakers with the following specs:

Diameter of Subwoofer (2) 15\"
Type Full Range
Frequency Range
(-10dB) 36Hz-20kHz
Nominal Impedance 4 ohm
Sensitivity 96dB
Power Handling (watts) 300 RMS/1200 Total
Crossover Frequency 2.5kHz
Maximum Peak SPL 127dB


I have tried taking the 260 GUI and loading the speaker config and then looking at the speaker specs but they dont seem to line up.

Dra

I am a little confused as to what gear that you have, but...
As a rule of thumb set the sub high pass (lo cut) to the -3db frequency point using BW18 and all other cross-over point filters should be LR24.

DRA

j.rahl

Sorry if there was confusion. We are using MTX p215h speakers. On the high pass and the low pass it says you can set the frequency response. I was curious as to how I set that for the MTX since it appears that I have just the range. In the All Outputs document dbx has it says to set unknown frequency response to 50Hz for the low and set the high at OUT. Thank you for the quick response!

Jason

Gadget

How about giving us ALL the info not just parts of it...
1. Subs
2. Tops
3. Amps
4. Purpose system is for

Model numbers and specs if possible, just like it requests in the READ ME FIRST BEFORE POSTING (or you won't get any answers) section...
There just isn't enough info to help you here...

Gadget

j.rahl

I wasnt trying to be vague and I apologize for not following the read me I just didnt think the information pertained to my question, which it does. I am a newb when it comes to sound so I think I am being cautious about not looking like a total idiot but my idiocy may be more obvious as you read.

1. Subs - None
2. Tops - Using an older model Yamaha speaker (sorry I am not sure of the model) hooked up to the High output. Also using MTXP215h hooked up to the Low output(they look like they are similar to the JBLJRX125s in the way you can use them. yes I know the MTX is not a JBL). The MTX specs are included in my previous post.
3. Amps - Crown Powerbase 3.
4. Purpose system is for - small church seats 250 at most.

In setting up the cross over it asks for the frequency. So that is where my question was coming from.

I was working fine previously with just my Yamahas and the DBX. The room had been pink noised and everything. Worked great.

We have the MTXes just sitting that we were not using and I was trying to put them in the dbx to see if it was possible to use them.

Following the doc All_Output_Full_Range I set the DBX to custom biamp, set the EQ up afterwards to the same as when I had the DBX originally setup, I set the X-over settings for the high at 50Hz, LR24, and 0db and the low 50Hz, LR24, and 0db and OUT LR24 and I could hear the Yamahas clear as day but the MTX were then very soft. On the board if I turned the MTX up at least twice what the Yamahas were but the Yamahas were still much louder. So I posted to the dbx forum and followed the suggestion on the low BW18 and then I played with the setting and my X-over is now set to

X-over setting
L -
37.5 Hz BW18 10db
OUT LR24

H-
50 Hz LR24 0db


This made the Yamahas and the MTX almost as loud as each other. That is where the 10db on the gain came in for the L on the DBX. On the board I had the Yamahas half of what the MTX were and so I set the gain on the X-over for the MTX to 10db and I thought it had totally fixed my issue.

Part way through our set the MTX speakers started to \"crackle\" so on the board they turned them down and it fixed the issue. I tried looking for the frequency response of the MTX and the only thing i find is they say they are tunable to anything you want. That is where my orginal question came in.

All of the equipment was installed a while back and all of it was installed by a \"professional\". They were not doing live music at the time. We are small and with that have a small budget so I am trying to make do with the speakers I have. The Yamahas are in the center of the church and the MTX are on the side. It sounds awesome right now but I want to make sure I have the settings where they need to be and really want to be sure I dont harm my equipment.

j.rahl

I have 2 Crown Powerbase3 amps. Yamahas on 1 and MTX on the other

Dra

The Yamaha's are flown in the center?
I would also set the MTX's to 50hz.
The yamaha's are probably more sensitive (more output with less input), but this is not a problem. Using the the mtx's to \"fill\" the front on the edges that the Yamaha's \"miss\" is fine, but to try to use all 4 cabs to \"fill the room with 2 times the sound is going to hurt more than help. I'd just use the MTX's to spritz the fringe that the Yamaha's miss. I bet that if you leave the MTX x-over at -0- it will work just fine for this purpose.

DRA

j.rahl

Exactly right! We had dead spots on the sides and the MTX gave the room a fullness the Yamahas by themselves werent accomplishing since they were in the center. I appreciate the response and thank you for all of your help!

Jason

Dra

-0- was just a guess. The best way to do what you want is have a second person sit in the center of the room bring the level up to a comfortable point (crossover gain on the MTX's down). Then have them move to the dead zone (front side extreme) then bring up the MTX gain until they signal you that the level is the same. Then do a simple walk through the pews / chairs and see if there are still dead spots. Aim speakers towards dead spots and away from hot spots in the front. Dead spots in the back (even on the sides) would require re-aiming the Yamahas. If the dead spots aren't too bad, that can be a good thing. Some people don't like it as loud and those with hearing aids hate it loud.
A db meter would be usefull. Also a \"book on CD\" would probable be better easier than music for this test.

Good luck.

DRA