Signal split, no sends left.. help

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Signal split, no sends left.. help

Post by funky54 »

Can I do this?

Image

If I split the send signal between the FOH EQ and the Crossover on one side... will that jack with both channels being at equal gain?

Before suggestion come for mono.. It must stay stereo.

The second delayed FOH speakers for further back in the venue will not be stereo. It’s ok. Those don’t need to be. They are only powered by on side of the sub amp. I’ll use DSP to kill frequencies on that side below 150hz, and Ill set the delay in the dsp for these.

Here’s what’s going on:
Image
Last edited by funky54 on Mon Oct 21, 2019 8:55 pm, edited 2 times in total.
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Re: Signal split, no sends left.. help

Post by Hugh Robjohns »

funky54 wrote:If I split the send signal between the FOH EQ and the Crossover on one side... will that jack with both channels being at equal gain?

Yes, you can take a passive split without losing any significant level.

Before suggestion come for mono.. It must stay stereo. The second delayed FOH speakers for further back in the venue will not be stereo. It’s ok. Those don’t need to be.

But not only will the delay speakers not be stereo, they will only be one channel... And I don't see anything providing the required delay, either!

I dont know how 'stereo' the main PA will be, but the apparently definite requirement for stereo suggests at least some sources will be hard panned, so the balance from the delay speakers could be significantly different from the stage sound. Not good...

It would be much better to feed the delay speakers with a genuine mono feed. If you really don't have a suitable spare mono send from the desk, I'd use balanced Y-splits from both main desk outputs (or the graphic outs, but why compromise the sound with the main PA correction EQ when you don't need to?), and feed them into the left/right inputs of an old spare digital FX unit. That can then be configured to sum them and provide a mono delay of the appropriate duration (1ms/foot distance). If you don't have a suitable FX unit lying around I'm sure you could borrow one from a friend somewhere, or even hire one.
Last edited by Hugh Robjohns on Mon Oct 21, 2019 9:45 pm, edited 1 time in total.
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Re: Signal split, no sends left.. help

Post by funky54 »

Hugh Robjohns wrote:
funky54 wrote:If I split the send signal between the FOH EQ and the Crossover on one side... will that jack with both channels being at equal gain?

Yes, you can take a passive split without losing any significant level.

Before suggestion come for mono.. It must stay stereo. The second delayed FOH speakers for further back in the venue will not be stereo. It’s ok. Those don’t need to be.

But not only will the delay speakers not be stereo, they will only be one channel... And I don see anything providing the delay, either!

I dont know how 'stereo' the main PA will be, but the definite requirement for stereo suggests at least some sources will be hard panned, so the balance from the delay speakers could be significantly different from the stage sound.

It would be much better to feed the delay speakers with a genuine mono feed. If you really don't have a suitable mono send from the desk, I'd use balanced Y-splits from both main outputs, and feed them into an old spare digital FX unit to sum them and provide a mono delay... If you don't have one lying around I'm sure you could borrow one from a friend somewhere, or even hire one.


First, thanks so much for the reply. I’ll likely move ahead with the splice as drawn. To provide some background and hopefully make sense of my shenanigans...

The delay and all frequencies above 150 hz can all be set in the dsp of the second side of the subwoofer amp.

I Hard Pan two guitar amps. They ping pong some special effects. There is a third amp that is even in both channels. The (3) vocals, lead guitar amp, bass drum, bass guitar and second guitar amp are balanced equally.

1 back up singer, snare, two guitar effects are all hard panned.

The back of the venue with the secondary aux mains will have the majority of the signal. These will be just cracked on with enough volume to help even the sound throughout.

I don’t have spare effect.. this is a larger gig for me and I’m using everything I have.

6X monitors
4X 12” 2 way mains
1X 15” sub
9X mic’s
4x line ins
2X different stereo in’s
Lighting, lasers, mirror balls....
Last edited by funky54 on Mon Oct 21, 2019 9:56 pm, edited 1 time in total.
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Re: Signal split, no sends left.. help

Post by funky54 »

Just following up. The “Y” splitter worked great. Zero problems, Zero ground loop issues. In fact Zero DB loss on the split side to the non-split side.

Delayed pair of speakers worked great. I set it at 60’ from the mains and just barley tweaked it to get it to sink nicely.

Only real problem was the bass was really lacking. My single 15” bag end sub wasn’t really enough for the venue.

I will comment that vocal and guitar amps ended up with all reverb off. But still sounded great with the natural coming back from the room.

Ended up running monitors in dual mono with 3x 8 ohm cabs a side.
Last edited by funky54 on Wed Nov 06, 2019 3:35 pm, edited 1 time in total.
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Re: Signal split, no sends left.. help

Post by Wonks »

Well done for sorting it out. Now time to save up for more subs!
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Re: Signal split, no sends left.. help

Post by Hugh Robjohns »

:thumbup:
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