Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Mark Coleman]

Hi,

I didn't even know what to search for for this question.

If I'm running my subwoofers from the single mono output of, for example a MixWiz3 16:2, via the traditional EQ/crossover (DBX 231 & 234XL, for example) signal path, how do I connect that single mono output into my two EQ channels and on to my two subwoofer amps?

These Y-cables ( http://www.thomann.de/ie/cae_90074_yaudiosplittkabel.htm ) seemed like they'd be useful, so we bought a couple when we bought our PA, but haven't had cause to use them yet. Could they achieve what I'm talking about, if I hook it all up like in this diagram?



Or is there another specific method or piece of connectivity/cabling we should use?

Or could it be connected in mono from the mixer into a single channel EQ and then on in mono into a crossover which would then split the signal into two outputs for the amps?

Thanks,

Mark

[Paul O'Brien]

You don't need the Y cable at all if your amps have parallel mono capability. The input signal will typically be available at the CH2 input terminals in this mode so you can use it to jump to another amp. If the signal is not available at CH2, then simply use a TRS patch from Ch1 input to the second amp Ch1 input.

[Phil LaDue]

What amps do you have?

[Tim Brackett]

That will certainly work but I would put the Y-cable between the crossover and amps and only use one side of the crossover and EQ.  Why have to adjust both channels when it is all the same signal anyway.  Then you have the other channel available for something else like a monitor send.  Alternately if your amps have parallel outputs you can just chain the two amps together with a regular cable.  Either way is the same electrically.  Do whichever is most convenient.

[Scott Deeter]

Mark Coleman wrote on Wed, 18 April 2007 10:26

Hi, If I'm running my subwoofers from the single mono output of, for example a MixWiz3 16:2, via the traditional EQ/crossover (DBX 231 & 234XL, for example) signal path, how do I connect that single mono output into my two EQ channels and on to my two subwoofer amps? Or could it be connected in mono from the mixer into a single channel EQ and then on in mono into a crossover which would then split the signal into two outputs for the amps? Thanks, Mark

Mark,

The first question would be "Are you running a Mono 2-way  System"?

If so, I believe the easiest way would be the way I show in the diagram (from my point of view). This would be if your amps allow the daisy chaining in mono parallel mode to additional amps.

[Brad Weber]

Quote:

If I'm running my subwoofers from the single mono output of, for example a MixWiz3 16:2, via the traditional EQ/crossover (DBX 231 & 234XL, for example) signal path, how do I connect that single mono output into my two EQ channels and on to my two subwoofer amps?

Maybe you just didn't show the complete system, but putting this statement together with the drawing makes it seem that you might actually be addressing a form of aux fed sub, perhaps with the mains fed via the main outputs.  Is this true or is the mixer mono out signal actually feeding a split mono, multi-way system?

Would having an open EQ and/or crossover channel be of any benefit?  Provided that all the subs are the same, there seems to be minimal times where you would get too much benefit from being able to adjust the left and right subs independent of one another.  But if there is no advantage by having the open channel on the EQ or crossover and you don't mind what may be some additional setup, it certainly wouldn't hurt to have it.

How to handle the amp inputs might also depend on the specific amplifiers and what connectivity they provide.

[Mark Coleman]

You're right Brad - aux-fed subs.

The band's kitty is slowly increasing so we should soon (this year) be getting a MixWiz3 16:2 to replace our current Peavey RQ2318.

I'm trying to put together a connectivity plan for our rig (always feels too cheesy to use "rig" to describe a weekend warrior's band PA, but it's quicker to type than "set-up". Or it would have been if I hadn't typed this qualifier     ), so any one of the band could hook it up without always relying on me.

I intend to have one rack carrying the mixer, all eqs and crossovers, with a custom connections panel on the back, and another rack carrying the three amps.

In previous posts of my own and by others, I've gotten loads of advice on aux-fed subs, mixer choice, simplifying connectivity and more, so before we decide on a revamped rig, I want to know as much as possible to avoide choosing inappropriate gear.

So the diagram I attached shows the aux-fed subs signal path of our intended new rig.

Our subs amps are two Yamaha P5000Ss.

We currently own:

RQ2318 mixer
DBX DRPA
DBX 231 eq
2 x P5000S amps for subs
1 x JBL MPA750 amp for tops (may need to replace with a third P5000S if our old guitarist asks for it back)
2 x JBL JRX125 tops
4 x JBL JRX118S subs
2 x TC M300 effects

Tempting as it may be for some of you, believe me - I've heard plenty of flaming of the JRX speakers, but they're what we have for now, so leave me alone . . .  

What we want to aim for is dual mono mains (nothing panned from centre - that makes it dual mono rather than stereo, yeah?) from MixWiz LR main outs into both channels of our current 231 eq, then into both channels of a new crossover (thinking of DBX 223 or 234), then into both channels of our current MPA750 amp and on into the JRX125s.

This dual-mono method allows us to raise or lower the volume of either left or right speaker stacks - some of our venues have a dancey side and a sit-down-and-chat side. I understand that the left/right separation functionality will be lost for the mono subs, but I plan to close-couple the subs in centre whenever possible, so it's not an issue, is it?

We thought the aux-fed subs could run from the MixWiz mono (dedicated aux-fed sub) out into our current DRPA, using the parametric eq (rather than the 28-band eq), to focus only on the sub frequencies (if necessary), and the crossover, then into our two current P5000S amps and on into the four JRX118Ss.

I had a look at the DRPA manual and I didn't see anything that confirmed that a single mono input could be summed to the two low outputs, though I'd assumed that the DRPA would be able to do it.

[EDIT: My mistake. I went back to the DRPA manual - the two inputs ARE mono summed to the two low outputs in two of the crossover modes:

"The crossover is stereo linked. Adjusting a parameter affects both the left and right outputs
of the current frequency band. For the 2x3 and 2x5 Crossover, the Left and Right inputs are
summed to produce a Mono signal that is processed by the Low Band Pass filter. After filtering,
the Mono signal is fed to both the Left and Right of the Low band output."]

I'll have a look at the P5000S manuals to see if the signal can chain out from channel 2 of one amp to channel 1 of the second amp.

Just did:

"STEREO/PARALLEL/BRIDGE switch
Use this switch to select the operating mode.
• STEREO mode
Channels A and B operate independently (as with a conventional
stereo amplifier). The Channel A input goes to the Channel
A output jacks, and the Channel B input goes to the
Channel B output jacks.
• PARALLEL mode
The Channel A input signal is output through both the Channel
A and Channel B output jacks. The Channel B input jacks do
not function. Channel A and B volumes can be independently
adjusted.
• BRIDGE mode
The Channel A input signal is output from the BRIDGE output
jacks. To adjust the volume, you must use the Channel A volume
control knob."

Doesn't say if the signal is present at input B. I'll e-mail Yamaha. In the meantime, do any of you guys know?

[EDIT: Just spoke with Yamaha UK tech support on the phone - the signal is not present at input B. He suggested chaining from the amp 1 channel A input 1/4" jack (the input from the crossover will be into the channel A XLR input) to the second amp's channel A 1/4" input jack - how's that sound to you guys?]

This brought me to the question in my OP. It seems that to send a singal from both left & right low outputs of the DRPA, it needs to be receiving signal into both left & right inputs.

I'm sure there are better or other ways to achieve what I'm talking about, but I'm trying to achieve aux-fed subs with a MixWiz3 16:2 with the minimal outlay.

We'd be selling:
RQ2318
2 x TC M300 effects (MixWiz has built-in effects)

We'd be buying:
MixWiz3 16:2
DBX 223 or 234 - I haven't researched which one suits purpose best for the lowest spend
Compressors - maybe 2 x DBX266XLs? We currently use the compressor from a TC M300 on the vocals in an effect send/return - that suffices, but the flexibility of having four dedicated quality (and good value) compressor channels to insert as required would be good to have.

One of the advantages of the MixWiz over the RQ2318 is the ability to run 4 separate monitor sends, so we'd probably also be buying another two dual 31-band graphic eqs - probably two more 231s.

We currently have no EQ on our two monitor sends. Monitors are 4 x active HK Audio Powerworks RS122MAs.

Thanks for the replies folks,

Mark

Now, where was I? Oh yeah - work!

[Dara Traynor]

Hi Mark,

Can't beat Thomann...

Based in Dublin too.

[Mark Coleman]

Hah!

Actually MusicStore gave us 10% discount when we were buying our PA & some other gear when Thomann wouldn't.

We still use both.

Mark

[Dara Traynor]

speaking of musicstore, do they still have a rep in ireland?  there used to be a guy in mayo or sligo area...think he stopped doing it though.

very hard to beat thomann on their prices and the gear they stock.