New to DRPA - A couple of questions regarding setup

fazmanicg

Hi All,
Learning a lot here. I appreciate the help.
Here is my setup.

Mackie Onyx1640 Mixer
(2) mackie C300z Full range Speakers (Mains)
(2) JBL MRX518S Subs
(2) Crown XTi 4000 Power Amps (These are set up as CH1+CH2 Y, where the left and right inputs are summed to both outputs. It is still regarded as stereo mode for the config wizard, I assume. You get another +6db in this config) Is this a good idea?

During the configuration wizard, I input all the equipment (I have selected the C300 for the mains, The spec are the same). When I get to the power amp level setting, it suggests 57% on the input for both amps. I assume this is a starting point since no gain structure has been performed yet. Is that true?

Once I finish the config wizard, I set up the gain structure as suggested here on this forum. Do I then go back to the config wizard and adjust the inputs to where they are after setting the gain structure? Is matching the levels in the config wizard that critical?

Also, I am crossing over @ 80hz. I would like to get a little more out of my subs. I don't seem to get that \"punch\" that I should. I do not want to use the autoEQ if it is going to take away from this setup. Could I set the crossover point to 100hz for instance, and will it make a difference in your opinions?

I know I could increase the gain on the Low crossover side, but I want to hear from you all first.

The problem is I do not have a place to set all this up and fiddle with it. I would like to get a good starting point before i get to a gig. I have been relying pretty much on meters to set this up (gain structure, etc).


Thanks all for assisting a newbie.

Dra

Welcome.

1) Running mono is not a problem. Where did you hear that you are getting +6db? The voltage is not doubled when you add two outputs from a board or Driverack, etc, together. If the left channel is outputing 1.2V and the right channel is outputing 1.2V, when you combine them they yield 1.2V, not 2.4V. You would have to invert the phase of one output to increase the voltage, but you would have less sound because of cancelations. But if you wish to run mono that is fine. There are advantages and disadvantagegs to it though.
Advantage - the whole room gets the same content. Pretty easy to wire up. Easier to use bridged amps for more power with fewer cable runs.
Disadvantage - Can't use stereo effects. Can't manipulate the sound stage (left side guitar \"appears\" to be playing from the left side of the stage, etc.)

2) Since you will be setting the gain structure manually anyway, just make a note of it and compare when you're though. Be sure ,if you haven't already, read the detailed FAQ / Wlecome post on gain and limiters. The DRPA does not have adjustable output control (in the wixard). The wizard is only a source of other people's findings (right or wrong), but for the most part can be trusted to be in the ball park.

3) Gadget recommends never crossing at 80hz (major kick drum harmonic). Your tops are only rated to 300w program. I would try no lower that 100hz and maybe as high as 125hz. Use a LR 24 setting for the x-over point and set a filter on the lo end of the sub (for protection) around 45hz BW 18.

4) Consider setting up a 2 x 3 (stereo tops and mono subs). Bridge the sub amp and run both subs together as a 4 ohm load (best together and in the center). A 2 x 4 setup also will work fine (no sub bridging).


Try this out and report back.

DRA

kpippen

Welcome to the forum fazmanicg,

fazmanicg wrote:

When I get to the power amp level setting, it suggests 57% on the input for both amps. I assume this is a starting point since no gain structure has been performed yet. Is that true?

Yes,...this is true...:)

fazmanicg wrote:

Do I then go back to the config wizard and adjust the inputs to where they are after setting the gain structure? Is matching the levels in the config wizard that critical?

After you set the gain structure DO NOT set your attenuators past the point that you marked (3dB below clipping)... You may adjust the attenuators anywhere below this point to suite your taste...

fazmanicg wrote:

Also, I am crossing over @ 80hz. I would like to get a little more out of my subs. I don't seem to get that "punch" that I should. I do not want to use the autoEQ if it is going to take away from this setup. Could I set the crossover point to 100hz for instance, and will it make a difference in your opinions?

We do not recommended to crossing any lower than 100Hz because 80Hz is critical frequency for kick drums.

fazmanicg wrote:

I know I could increase the gain on the Low crossover side, but I want to hear from you all first.

I normally recommend to set the gain at +3db for subs and 0dB for tops only as a starting point...

fazmanicg wrote:

The problem is I do not have a place to set all this up and fiddle with it. I would like to get a good starting point before i get to a gig. I have been relying pretty much on meters to set this up (gain structure, etc).

It appears that you have done your homework...you will do fine...:)

Cheers,

Kevin

Edit: Looks like Dra beat me to the punch here!... Anyways,...I recommend that you follow his or Gadgets suggestions before mine...:)

fazmanicg

Wow. Great stuff. Thanks for the quick replies.

As for the +6db boost. it is on page 24 of the XTi4000 user manual

http://www.crownaudio.com/pdf/amps/139548.pdf

Here is what it states:
DSP PROCESSES
The XTi amplifier includes a number of DSP processes, which appear as ICONS on the screen. They are described below:

Y (Input Y):

• CH1+CH2 (Ch.1 input signal and Ch. 2 input signal are summed and fed to both output channels.) This provides a 6 dB level boost.

• INPUT Y (Ch. 1 input signal goes to Ch. 1 and Ch. 2 output. Ch. 2 input signal is ignored.)

• STEREO (Ch. 1 input goes to Ch. 1 output. Ch. 2 input goes to Ch. 2 output.)

---

Since I have (2) mrx518s, I cannot run the low amp (xti4000) in bridge mode because they are 4 ohms.

I would like to hear your thoughts on the 6db level boost thing.

kpippen

Hello fazmanicg,

First off I always recommend following Dra's or Gadget's suggestions before mine...:D

The following suggestions are only my opinions or personal preference... When setting up a system like this there are going to be trade-offs...and the main goal is to come-up with something that sounds great to you or your customer(s)...

I looked-up your amps and speakers on the web... The first thing I would do is disable the DSP feature on the amps because this would simplify things considerably... This also eliminates the possibility of redundancy, confilct, and confusion :?...plus it allows the DRPA to be \"the DSP\"... You can easily \"dB boost\" by lifting the crossover gains in the DriveRack... I recommended a \"3dB boost\" for your subs... Personally,...I love lots of earthmoving, chest-thumping bass... You can always experiment with the XTI's advanced features once your system is up and running...:)

I would choose a custom 2X4 stereo configuration as illustrated below... I used the DR260 DriveWare Wizard to configure this 2X4 and it's only a good starting point... I recommend that you click here and download the DriveWare GUI... Play around with the DriveWare and get yourself familiar with it... The below settings should work...but you will need to key them manually with the DRPA... Mr. Dra recommends sitting at the kitchen table, poking around, and getting familiar with the menus and screens…

It's not going to sound “great� until you set the gain structure, the time delay between the subs and tops, and perform an Auto-EQ (for inside use only) with the RTA mic... If you perform the Auto-EQ only enable one side (mute the other), adjust the gain (volume in this case) to the venue listening level, and use the fast mode... Once it has completed set everything (in the GEQ) from 0-100Hz flat (at 0dB) and adjust everything from 7kHz and above to suite your taste...

You may also want to read this thread because there is lots of good information scattered through out...:)





Cheers,

Kevin

Dra

Kevin is too kind when giving me credit for the kitchen table remark. I stole that from Gadget. Let's give credit where credit is due.

You are right about the sub cabs being 4 ohm. When the driveware showed a single 18 and offered to bridged the Xti4000 I jumped the gun.

DRA

fazmanicg

Thanks for some GREAT info. It will make for a good starting point. I am going to hook up the system in my garage and actually make some noise. It is pretty large. I'll bring 6 packs to my neighbors just before i Auto EQ the system. I'll report back when I have more.

Once again, You folks offer invaluable insight and guidance
Much appreciated.

kpippen

fazmanicg wrote:

I'll bring 6 packs to my neighbors just before i Auto EQ the system.

Don't forget Dra and I!...:shock:

Yes,...please post back and let us know how it goes...:)

Cheers,

Kevin

fazmanicg

Well, After delivering the beer to the neighbors, I set up my PA in the garage and set it up as Kevin had suggested. I then performed the gain structure routine. Once that was done, I did perform the AutoEQ.

Here is what happened when I put some audio through the system and slowly turned up the volume ............. BIG BIG BIG SMILE !!!!!!

I cannot believe the difference! It sounds phenomenal!
I actually feel the low end in my chest, and the tops performed beautifully. The system is So much louder than it was prior to this setup. The nice thing is, the amps are hardly breathing. No RED lights anywhere.

Since I am a Bass player and run sound, you can imagine my relief knowing I do not have to worry about clipping anything anymore. I play in a funk/top 40 cover band.

BTW - I cranked up \"Soul with a capital S\" by Tower of Power to listen to the system. It has a great Kick drum, Bass & snare sound. The mix is real tight. If you have not heard this tune, listen to it.

I cannot say enough about the help you guys have given me (Especially Kevin .....) I DO owe you some Beers !!!

Thanks Again,
Peter

kpippen

Hello Peter,

Dra and Gadget deserve all of the credit here!... If it weren't for them I couldn't of helped you... They taught me everything I know about the DriveRack...and lots more about pro-audio...

In fact I can't say this enough... Thank you Dra and Gadget!...:D

Now bout those beers....

Cheers!

Kevin

kpippen

fazmanicg wrote:

Since I am a Bass player and run sound, you can imagine my relief knowing I do not have to worry about clipping anything anymore. I play in a funk/top 40 cover band.

Hey Peter,

Have you tried the Tech 21 Sansamp Bass Driver DI box?... I bought one of these for a system and the bass player's think it's great!...

Kevin

fazmanicg

I use that in my studio and for rehearsals. For live gigs, I use the Fishman Pro-EQ Platinum Bass Preamp. It is outstanding for funk/slap style playing. I play an alembic Bass. The combination is second to none.


http://www.gollihur.com/kkbass/preamp-fishman.html

kpippen

Peter,

Looks like a wicked unit!...8)

Hey just looked into the +6dB boost thing and what it does is...sums both of the input channels and routes the summed signal to both of the output channels... It's a summed-parallel kind of thing... If you use this feature you'll back to a mono system... Now if they came out with a summed-bridged mode...that would be useful I think... Personally,...I prefer good ole stereo...either using two amps in bridged mode or one amp in stereo mode...:)

Input Y is what everyone else calls parallel...

I'm sticking to my guns in suggesting on NOT using the XTI DSP functions...

Cheers,

Kevin

fazmanicg

Thanks Kevin. I did turn off ALL DSP functions yesterday when I set up the PA and did all the tweaks. I could not be happier with the way it sounds and performs. It is running in Stereo.

Thanks Again

Gadget

Ahhh..you guys make me real proud...I too own and use a Sans Amp Di..cool tool! Thanks for the kind words..I started out just like you guys.. I was/am a sponge...plus I LOVE THE INTERNET! I could probably get a degree in almost everything just by studying on line :!:

Be well Rock hard!
Gadget

kpippen

Hey Peter,

Assuming that the DRPA has it... When you go live you'll want to enable the AFS (Anti-Feedback Suppression)...

1. Turn AFS On 2. Set mode to Live 3. Set type to Music High 4. Turn Filter Lift On 5. Lift after 5 Seconds 6. Set Fixed Filters to 6 7. Set Total Filters to 12

Hey Gadget,...This brings up a question... Suppose your late for a live gig and you don't have time to ring-out the system... Couldn't you just set the fixed filters to zero so all twelve filters are live?... What harm would it do?...:?

Kevin

fazmanicg

I will try that at our next gig. I will post back when I do. It's not for a couple of weeks. But I will be sure to report back.

BTW - Kevin, DRA & Gadget ...... What kind of beer do y'all like ?

Thanks

Dra

IBC

DRA

kpippen

I love IBC!... The ultimate root beer!... Diet for me though...:)

Cheers,

Kevin

Gadget

Well,
If your system is properly tuned you really won't need the feedback eliminator till you start getting stupid loud... and if you need to get that loud you need to have a separate tuning for that eventuality. Take my monitor rig for example... the thing is stupid loud and you can point the mic right at the monitors and sweep the whole way even point at the horn and it doesn't feed back. It's the systems that have hot spots in their response that have feedback issues.. or those that have too much piercing hf in the mix... these are the things that leave people with ringing ears at the end of the night. I have goofball singers that stand on the subs right in front of the mains and scream bloody murder.. no feedback...

But I guess that would work fine... but if you clear all the filters first.. all the filters are live and the first 6 will catch and hold and the other 6 will roam...


G

kpippen

OK,...Maybe it's time for a little Gadget AFS-101?...:D

kpippen wrote:

Hey Gadget,...This brings up a question... Suppose your late for a live gig and you don't have time to ring-out the system... Couldn't you just set the fixed filters to zero so all twelve filters are live?... What harm would it do?...

Gadget wrote:

But I guess that would work fine... but if you clear all the filters first.. all the filters are live and the first 6 will catch and hold and the other 6 will roam...

Why would you need to clear all of the filters first?... Also if the filter lift is set a 5 seconds would the each of the first 6 lift after 5 seconds?... Would you please explain the DriveRack AFS mechanics?...:?

Sorry,

Kevin

Gadget

K...

But not tonite...

G

kpippen

Gadget,

I will re-phrase and re-post my question under the \"Audiophile thread\"...so we can keep all this good \"101 lesson\" stuff under one roof...:D

Thanks!

Kevin

stublito

Can you switch stereo/dual mono EQ after you finish using the wizard? I want to preserve my EQ setting if I can.

THanks

Peter

Gadget

DRPA... sorry...
260... NO PROBLEM!

G