another IEM question

[Matej]

Hello!

 

I'm planning on buying IEM system mostly for use with 8 piece band. The problem is that the mixer that our sound technician uses only has 4 monitor lines. Until now I was using keyboard amp (I'm embarassed to admit which one), and rely on hearing other musicians directly from stage.

But in IEM I would need to get mix of everyone and there isn't a monitor line available. One solution would be to get main mix and add keyboards with my own mixer to hear myself a little better. I'm concerned that this would cause phase issues with keyboard sounds as the keyboard sound in main mix signal would be slightly delayed in comparison to signal directly from keyboards.

Could this be a problem or it wouldn't be noticeable?

Does anyone use this configuration?

 

There is also a posibility that other band members start using IEMs, so maybe we'll have to find a solution for everyone. Any suggestions?

 

Thanks for your answers!

[Matej]

So, does nobody use foh mix in their in-ears?

Do you all get your monitor mix?

 

I experimented a little on computer: two identical tracks played at the same time, but one was delayed a few milliseconds. When the levels of the tracks are similar, the resulting comb filtering effect is terrible.

And if I understand correctly, that is what will happen when mixing foh mix with my keyboard mix.

 

I'm thinking of solving the problem by also delaying the keyboard signal.

I guess I would need to use some sort of speaker management DSP, because with typical FX processors you can't adjust delay time precisely.

But I can't find information about smallest increment of delay time of different processors.

 

Does anybody have any suggestion?

 

The cheapest thing I found that might do what I need is this:

http://www.thomann.de/gb/the_tracks_ds_24.htm

 

Of course I would need to tune the delay time to exactly the right amount, but I can do it with computer by measuring the delay between both signals.

 

The other thing I need is a limiter to protect my hearing if sound technician makes a mistake.

I can get Behringer mdx2600 composer pro-xl second hand very cheap.

Will it do the job?

 

Thanks,

Matej

[ksoper]

Welcome, Matej.

 

Not sure I'd use a foh mix back in my IEMs for a bunch of reasons. I'd get a small mixer that could accomodate all your inputs (and then some, just in case) and set a mike on stage that would run into a buss on your mixer that wasn't going to the foh. You'll get plenty of you, plus a reasonable representation of what's happening on stage.

 

And I'm sure that once the other guys wake up they'll have better suggestions than this.

 

Good luck.

 

K.

[MoKen]

I use foh in my IEM mix. Never noticed any time delay. Of course the foh mixer/amp is on the stage (small venue). Perhaps if it was going through a snake out to a remote mixer and back it might be noticable???

 

Test it in your situation. Don't spend time curing a problem you don't have.

[jimw]

I run my keys and vocal mic into my Mackie keyboard mixer. I also run a monitor mix from one of the FOH mixer aux sends into the same mixer. The main output from my keyboard mixer feeds my Shure hardwired bodypack for my in ears. I run my vocals and keys out of the two aux sends of my keyboard mixer to the FOH. This gives me the flexibility of controlling my vocals, keys, and monitor levels in my in ears independently.

 

I've never noticed any delay. I would think you only get a delay from the actual main speaker (acoustic) outputs, and not through any "wired" signals.

[Eric Jx]

I would think you only get a delay from the actual main speaker (acoustic) outputs, and not through any "wired" signals.

 

You'd get a delay (latency) if any part of the signal chain was converted to digital (i.e. you were using a digital mixer).

[Matej]

Thank you for your answers!

 

First of all it looks like the problem solved itself. We are going to use other sound technician and PA system for majority of our gigs (for reasons not related to my problem). There will be more monitor lines available, so I can have my own line with everything except keyboards. I will use a small mixer to add keyboards myself in a setup similar to the one jimw describes.

 

 

Not sure I'd use a foh mix back in my IEMs for a bunch of reasons. I'd get a small mixer that could accomodate all your inputs (and then some, just in case) and set a mike on stage that would run into a buss on your mixer that wasn't going to the foh. You'll get plenty of you, plus a reasonable representation of what's happening on stage.

 

What are the reasons you wouldn't use foh mix in IEMs?

One of the reasons I'm planning to use IEMs is because I want to clearly hear what everyone else in the band are doing. If I just used one mic for that it could be worse than now, because the information about direction of sound would be lost (of course I could use 2 mics, maybe even in binaural arrangement imagine using a dummy head on stage ).

On the other hand it's true that even one mic can be placed on the center of stage and get a better balance of everybody than I get now in the corner of stage. But there would still be a problem in places with to much reverberation on stage. In places with good acoustics and little reverberation there isn't much need for IEMs in the first place.

 

 

I use foh in my IEM mix. Never noticed any time delay. Of course the foh mixer/amp is on the stage (small venue). Perhaps if it was going through a snake out to a remote mixer and back it might be noticable???

 

You probably wouldn't notice such a small delay (1 or 2 ms for digital mixers I think). The problem would be when mixing keyboards signal with identical but slightly delayed signal which is contained in foh mix. The result would be comb filtering (http://en.wikipedia.org/wiki/Comb_filter).

 

Test it in your situation. Don't spend time curing a problem you don't have.

 

Good advice.

 

 

So now I only need mixer, limiter and headphone amp.

I currently use Korg KMX-62 line mixer for keyboards. I can continue using it and add a small mixer with just 2 outputs for IEMs. The other option is to replace my Korg with bigger mixer with at least 4 outputs (2 for PA, 2 for IEMs) as ksoper and jimw suggested.

 

I like the idea of separate mixers a little better, because I can keep line mixer always set up the same way and have less faders on IEM mixer to worry about (I currently use 6 channels for keyboards).

What do you think? I will need rack in both cases.

 

The next question is should I use limiter before mixer or after mixer. I don't think there is much difference, but if I use it before mixer, I don't need separate headphone amp, as I can just buy mixer with headphone output.

 

And what do you think of that Behringer mdx2600 composer pro-xl as limiter?

I know it does a lot of things I don't need, but I can get it cheap.

[ksoper]

Not sure I'd use a foh mix back in my IEMs for a bunch of reasons.

 

Well, at least in larger venue situations, the foh mix is a blend of what's coming off the stage (to a degree) plus whatever the engineer thinks needs to be in the mix at a particular time. Many times the foh mix will be lead-vocal heavy. And because a foh mix isn't static, you really can't be sure what you're going to get from song to song, venue to venue. At least taking a feed off the monitor mix you have a more stable mix.

 

I say this never having used a foh mix in my iems. I just have reservations about it.