How to use effects on a board?

[SpeedKing]

How do I hook up effects units to send through to different channels on a mixer (I have a crappy 32 channel Behringer Eurodesk mixer)? From what I thought, I would put it in an aux send and then with my aux send knobs, I can put as much or as little of the effect I wanted, but this doesn't seem to work.

 

Can anyone help me how I would put in effects units to as many channels as needed? (ie, if I had a compressor and needed it on 5 channels..how do I set that up correctly)

[jason_oates]

If you're wanting to compress several channels like background vocals, you could route all the vocal channels to a subgroup and use the inserts for that channel to go to the compressor. If you're wanting reverb or other fx for multiple channels, using a post-fader aux channel would be best. If you use the inserts, you will need an insert cable which basically is a trs cable that splits into two ts cables. If you're going from the aux, you would plug the aux send from the board into the inputs on the fx, and the outputs into the return. If you wanted, you could also plug the output of the fx into one of the channels not being used. Just depends on how you want to route it. Hope this makes sense, it's like 2am here and I'm half-awake.

[SpeedKing]

Okay, that's interesting. If I did want to insert the FX into an unused channel, how would I go about this (I know this is how it's done when you mix a record, but I'm interested in this particular method)

[SpeedKing]

When I tried to use an aux send (and aux return) the effected voice sounded like there was a phase problem?

[jason_oates]

You'd still hook up the inputs as usual. Then basically you'd take the output on the FX (usually a 1/4" ts cable) and just go line in on an unused channel on the board. For us it's easier than bringing extra rack equipent for our guy running monitors. He can pick this send up off our split snake and then mix it into the band's monitor mixes. I find it useful as well when you're doing monitors from FOH as well. You can then mix in the FX into the different monitor sends as needed. Not necessarily better than going back into the return on the aux send, just different i guess.

[SpeedKing]

Oh, I meant if I were to hook up the FX unit output into the line in of an unused channel, how do I add/subract that FX say on a vocal track, guitar track, etc..?

 

Maybe I'm missing this, it's just kind of a mind{censored} for a beginner.

[jason_oates]

You would still use the aux channel's knobs on the vocal channel, bass channel, etc. to select the amount of fx.

[SpeedKing]

OK, I would understand how aux knobs would work for the monitors, but how would you input the amount of FX for the FOH speakers? I mean, how would you assign the amount of FX you would want on each channel (wouldn't the aux sends alter the amount in each monitor, but not the FOH?)

[InACanProductions]

Lets say your FX unit is on Aux 3, set post fader, and your monitor mixes are on Aux 1 & 2 set pre fader. The FX on aux 3 will not be present on Aux 1 & 2. If you run your FX back into a channel then the fader controls the output of the FX to FOH same as the Aux return except it uses a fader and not a knob, note the fader doesn't change the proportion of FX on each channel (you still have to use the channel's Aux send), it raises or lowers the amout of the FX in the mix (it acts like the master aux return knob). I've only run my FX this way a couple of times so someone else can maybe chime in, but I would say don't have the FX return channel present in the monitor mixes. The FX will be set for FOH and will include everything that you sent to the unit which could put in a lot of unwanted material and really muddy up your monitor mix (ie. you might have the snare, guitars and vocals going to the same reverb, but you only want vocal in the monitor). If you're using more than 1 channel of FX you might be ok if say vocals are on 1 channel and everything else is on another, then blending a little of the vocal FX might be good, you'll have to see on a case to case basis. Also, don't send the FX return channel back to the FX unit. You'll be layering FX on top of eachother and I'm not sure if that would cause any kind of feedback but I'm betting the result wouldn't be pleasent either way. Again the last 2 points are based on minimal expierence with this set up so hopefully someone will step up and fix any misinformation.

 

For inserting a compressor on multiple channels, assign them to a subgroup and use the insert for that subgroup out to your compressor. Watch out for double assigning (assigning to the subgroup and the main out), and make sure you assign the subgroup to the mains. As was mentioned you'll need an insert cable. Just make sure you have the 2 TS ends hooked up right into the FX unit, obviously one is a send and one is a return.

 

There's lots of info on this forum if you search for it, and read the guide at the top of the first page, it's got tons of useful information, and some proper terminalogy that might make your searches more successful. Good Luck.

[SpeedKing]

That is why I had issues! If I send the input of the FX into the aux send, how do I setup the FX's output and the Aux return? The way I had it set was FX input into Aux Send, FX output into the Aux Return, and I realize now that I'm sending the FX back into each other, causing the phase problem.

 

How do I properly do this?

 

And I still don't understand how returning an FX onto an unused channel can control separate FX (say the amount of reverb on a vocal and snare track) to the FOH speakers..I understand that the aux sends can control the amount in the monitors, but how would you control that separately to FOH? It seems to me that inserting it on an unused channel will affect the entire mix, and will not be able to control separate channels, except in the monitors.

 

HELP!

[boseengineer]

Couple of things:

 

First, there are two different types of effects, serial and parallel effects. "Serial" effects require the whole signal to go through. "Parallel" effects mix a some amount of effect to the original (clean, unprocessed) signal.

 

Examples

Serial Effects: EQ, Compressor/Limiter, Distortion, Pitch Shifter

Parallel Effects: Reverb, Delay, Chorus

 

The hookup for both type of effects is quite different:

 

Serial effects need to go into the "insert" loop of the channel or between instrument/mic and channel input.

 

Parallel effects can be hooked up through an Aux on the board. Let's say you have a reverb.

 

1) Find a "post-fade" aux path (say Aux 1). Pre-fade WILL NOT WORK (at least not well)

2) Connect Aux 1 Send to the "input" of your reverb

3) Connect the output of your reverb to the Aux 1 Return (stereo as necessary or desired)

4) Gain stage: That's a royal part in the neck, but a good starting point is "All AUX 1 channel controls all the way down", "Aux 1 Send" and "Aux 1 return" controls (if applicable) to unity gain or 12 o'clock (if they are not properly labeled). Input and output controls on the effects unit to unity gain or 12 o'clock.

5) Set the desired level of effect on every channel by using the channel's Aux 1 control

6) You need to adjust the gain staging (using meters) when its either noisy or you don't get enough effect with the channel Aux controls

 

Instead of the Aux return you can bring the effects back through a spare channel, in which case you can EQ the effects signal. Your channel fader and trim takes the role Aux Return control. The gain staging is a little more complicated but it gives more flexibility.

[SpeedKing]

Thanks for all the replies.

 

I guess I'm still confused, however, because if I do put the input of the FX into the aux send and the output of the FX into the aux return, wouldn't that be sending that to itself (which I think is causing my phase problem). Also, if I did it with this method, there wouldn't be any FX going to FOH, because I can only adjust the amount in the aux sends, so that would only be going to the monitors, wouldn't it?

 

Second, I'm just still LARGELY confused as to how the hell you can control the amount of FX desired in whichever channels that are FOH. I understand how you could control this through the monitors (through the aux sends), but how would you control the amount and which channels you would want to have effects, in the FOH.

 

Why am I having this "phase" problem? It sounds like it's clipping, and overloading the FX unit, whether I hook it up through the aux return/send or if I hook it up through an aux send/unused channel..what am I hooking up wrong?

[boseengineer]

What effects unit do you have ? What exactly is your mixer ?

 

Some checkpoints

 

a) If your have a "serial" effect (as described earlier) you need to set the "mix" control on the effects unit to all the way up. You want as little as possible "dry" sound coming back to the Aux Return. If it's a digital effect it will almost certainly have some latency and remixing it with the orginal dry signal would produce the phase issues you describe

 

b) if there are any level meters on your effects unit check those and make sure you don't overdrive inputs or outputs. If you have solo on the board, solo Aux Send and Aux return and check levels there

 

c) Make sure you use a "POST FADE" aux

[SpeedKing]

I'm definitely not overdriving the unit, and I'm talking primarily about parallel effects (reverb, delay). I'm also using the post fade aux as well.

 

I don't know what's wrong, but the delays don't sound right..they sound like crap. The only way so far I've gotten it to work properly, is hook it up to the vocal mic directly so:

 

vocal mic --> FX in --> FX out --> vocal channel

 

and this is NOT how i want to set it up, but so far the only way where it sounds "correct"

[boseengineer]

Does your delay has "mix" control ? If you have it in the Aux path that needs to be all the way up, i.e. you want ONLY the delayed sound and none of the orginal sound coming out of the effects processor. Some effects processors have an option to turn the orginal signal completely off (which is good).

If you tell your brand & type of processor I may be able to help you better.

[SpeedKing]

Actually, I don't have a REAL FX unit yet, I'm just toying with a POD right now just to see how it would sound. It's the same kind of noise when I put plug in my TC Electronic G-Force incorrectly into my Dual Rectifier FX Loop..I'm hooking wires the wrong way and I dont know what/how to fix this

[flanc]

What kind of mixer do you have? You should have some post fader Aux send that you hook to the input of the effects unit and the output can run into an aux return or another channel.

 

You control how much signal from the channel is sent over to the aux snd X (lets say 3) by adjusting the POT on the aux 3 of each particular channel. That feeds this variable amount of signal to a bus or send that carries it to the input of the effects device. Because that Aux 3 bus is connected to each channel, you can send a littler or alot of signal to the bus from each channel to taste. That way the same effects unit can be used to provide a common effect to all channels if so desired.

 

So you basically have a mixed down signal that comes from this aux send bus. This feeds the input to your effects unit. Care needs to be taken hear not to be too hot on your levels so as to distort the signal. If that's the case, you normally can turn the input knob on the effects unit down or turn down each channel that is feeding the aux bus a to get things in line.

 

The output of the effects device now has to be routed to the main bus of the mixer in order to be included in your main mix. Remember, you dry (unprocessed) signal carried on past the aux bus and was mixed into your main mix already. What you are feeding in now is totally wet/processed effect (lets just say reverb). Mix the signal into your main mix and adjust to taste.

 

This acutally is a bit of a complicated concept to grasp initially, but once you get it is very easy.

[boseengineer]

I think I know where the problem is. The POD is a digital processor and has probably 2 or 3 ms latency (= delay) in the signal path, even for the clean signal. I don't think you can use a POD to produce purely the effect signal and elimiate all the original signal.

 

So what you get is your original signal through the board mixed to gether with the same signal delayed by a couple of milliseconds through the POD. That will certainly give interesting phase issues.

 

Let's say you want to use the reverb in the POD. On the patch that you are using, try to turn the amount of reverb as high up as it will go and see if that makes it better.

 

The POD is certainly not a particular good choice as an effects processor. It's really designed as a "serial" effect since it does a lot to the signal including aggressive amp, speaker and mic modelling, which is really not compatible with your orginal signal.

Try to select "line 6 Clean" as the amp, select "2x12" as the output mode, tone controls on flat and keep the drive level really low.

 

Hope that helps

[flanc]

I agree that the POD could be a problem...but I doubt 2 or 3ms will be the problem??

 

The input to the pod is for a high impedance guitar cable and at instrument level....maybe that's a problem.

[InACanProductions]

 

Originally posted by SpeedKing Thanks for all the replies. I guess I'm still confused, however, because if I do put the input of the FX into the aux send and the output of the FX into the aux return, wouldn't that be sending that to itself (which I think is causing my phase problem). Also, if I did it with this method, there wouldn't be any FX going to FOH, because I can only adjust the amount in the aux sends, so that would only be going to the monitors, wouldn't it? Second, I'm just still LARGELY confused as to how the hell you can control the amount of FX desired in whichever channels that are FOH. I understand how you could control this through the monitors (through the aux sends), but how would you control the amount and which channels you would want to have effects, in the FOH. Why am I having this "phase" problem? It sounds like it's clipping, and overloading the FX unit, whether I hook it up through the aux return/send or if I hook it up through an aux send/unused channel..what am I hooking up wrong?

 

 

Just because you're using an Aux send for your FX and one for your monitors doesn't mean they are connected. The other aux sends won't see any of the FX. When you route your FX unit back into the Aux Return, that aux return is going to FOH and not the other aux sends (on some boards it is assignable to subgroups and main out but I checked the manual for the Behringer Eurodesk MX3282A [that's your board right?] and stereo aux return groups 1&2 are assignable to tape out and Main mix where 3&4 are routed to Main Mix- read: you can assign the aux returns for Aux 1-4 to tape and main mix, and aux 5-8 to main mix only). The Aux return is just that, a return point for the effect to come back into the board, it doesn't affect any of the other aux sends or returns. On your board those returns are sent to the main mix.

 

The Aux knob on the channel is controling how much of that channel gets the FX, then there should be a master Aux Send knob which controls the over all level of each aux group (example: channels 1, 3, and 7 have Aux 3 running FX, the channel aux 3 knob controls the mix to the FX unit, the master Aux 3 Send knob controls the level of that mix to the FX unit). Then there should be a knob for Aux return. Now that is how much of the FX is brought into the FOH mix.

 

Now it's possible to bring your FX back into the board via an unused channel (instead of the Aux Return) which then gives you the use of a fader to control the over all blend of the FX mix (which you set up using the channel Aux send knobs) to the FOH. When you want to change an individual channel's FX you have to adjust it on that channel strip's Aux knob.

 

Is it possible you're overloading the signal on the aux return by having the out put level on the POD set too high.

 

My suggestion is to start from scratch with only 1 source and don't worry about returning the FX on a channel just yet.

- Zero out the aux sends on all the channels (at least the aux you want to use for FX - I suggest Aux 3 as 1 & 2 should be switchable pre on your board and you want a Post for your FX).

- Run a 1/4" TS cable from the Aux Send (3) to the input on your FX unit (POD in this case)

- Run a 1/4" TS cable from the output of your FX unit (POD) to the Aux Return (3)

- Plug a mic into a channel (1) and set your gain/levels so you've got dry signal coming through your speakers.

- set your Aux (3) Send Master knob to unity (12 o'clock) and your Aux (3) Return knob to let's say 9 o'clock (don't want to send an accidental clipped signal to the FOH).

- Turn up the Aux (3) knob on the channel (1) you plugged the mic into until you hear the effect blended in.

- Adjust the Aux (3) Return to get your overall wet/dry mix with FOH, then adjust the Aux (3) knob on the channel strip to get what you want on that individual source.

 

I'd keep the level on the POD low, make sure there's no cabinet emulation on, or anything other than the effect you want until you get it working right.

[boseengineer]

Originally posted by flanc I agree that the POD could be a problem...but I doubt 2 or 3ms will be the problem?? The input to the pod is for a high impedance guitar cable and at instrument level....maybe that's a problem.

Normally a millisecond is not much of a deal. However if you recombine the original and delayed signal you can get comb filtering. Let's say the delay through the POD is 1 ms and otherwise it's flat and you add orginal and delayed at the same amplitude. At 500 Hz the original and original signal are out of phase (1ms is half a wavelength at 500 Hz) and cancel each other. At 1 kHz they add in phase and you get +6dB. At 1500 Hz is out of phase again, etc.

 

I don't think the impedance matters much.