Vocal quartet live sound reinforcement...

[Donnie Frank]

SAC-heads;

Long time, no post. I hope all is well with everyone. I have a gig coming up, and need to draw on the collective experience of this forum.

I have an upcoming show doing live sound reinforcement for a vocal quartet competition. I would normally think that this would be a piece of cake, but there are some variables that may make throw some wrenches in the spokes of my otherwise easy gig.

Variables:

1) These are not professional singers. So providing 4 mic's is out of the question. Unpredictable mic techniques will surely wreak havoc with the FOH and monitor mix. I have a feeling that dealing with these varying, horrible mic techniques will be like trying to herd cats. So that's out of the question. Also, a lot of these guys have choreography, which naturally negates being married to a single mic on a stand. I don't have 4, wireless headset mic's.

2) They're going to want a vocal monitor. I don't think the vocal monitor will have to be very loud....probably just loud enough to provide some vocal clarity to the artists.

3) Most quartets stand in a semi-circle. But they may have some choreography that may break them out of the semi-circle.


I have done some research, and it's clear to me that I need to avoid large diaphragm condenser mic's.

The other thing I think I need to avoid is dual mic setups. I've seen dual microphone setups on a single stand, but surely this breaks the 3:1 rule, and would subject the audience to a "thin" sound. Any thoughts on that?

In my mind I'm thinking this is going to be more about mic and monitor placement than the electronics used. I'm probably going to use my MixWizard, but I *may* use a small SAC rig. Last time I tried to use my mini, 8-channel SAC rig, I ran into problems with the RME card (Laptop), so maybe I'll use the full rig...who knows.... But I digress... I also plan on using a pair of K12's for mains and a single K8 for floor wedge. I thought about dual monitors, and I may try that, but methinks a single K8, with it's 105° of coverage, should work nicely.

I'm pretty sure I'm going to use a single mic on a stand...probably high-passed @ 100Hz or so. I'm just not sure if I should use a small diaphragm condenser or dynamic microphone. Methinks the old, trusty 58 should work just fine, but might produce thin results. So then I think a condenser mic is the answer, but that might net feedback problems.

At this point I'm more curious about mic/monitor placement and mic angle. Naturally I'm going to want to keep the monitor in the dip of the microphone's cardioid pattern. Being an "out of the box" thinker, I'm toying with the idea that a LOWER microphone - say 4' high - might facilitate keeping the monitor behind the cardioid pattern, while simultaneously keeping the vocals in the lobe of the cardioid. I've never seen anyone use this technique, but "unconventional" has never stopped me before.

Anyone have experience with mic'ing quartets? Advice? Caveats? Dynamic or condenser?

Regards,

[cgrafx]

A single Dynamic mic, particularly an SM58 is pretty much the worst option you could pick.

Dynamic mics suffer from proximity effect (the bass response changes in relation to the distance from the mic). It will sound terrible.

I'd do two condensers configured in xy orientation or a set of LDC (You could even get away with a single Omni Directional Condensor, but you'll have to be careful about feedback.

I'm not sure you need the floor monitor. If its an acapella group, it really doesn't serve any purpose as they should already be used to singing without a monitor and there wouldn't be any reason for them to be amplified on stage.

When I've had to do choral groups I have a pair of AT2020's that I put up on boom stands, generally a couple of feet from each other, facing partially out L/R to cover the stage.

[Richard Rupert]

I don't believe proximity effect is limited to dynamic mics; rather it's a characteristic associated with a cardioid pattern on any mic.

Despite your first point Donnie, in this situation I probably would hand each guy an SM-58 and then (relatively heavily) compress each mic. I'd then get a quick mix based on their individual vocal strengths (levels) and go from there.

I agree that a monitor shouldn't be required for an a capella performance. They'll be close enough to each other to hear all the parts.

I should add that most of my work is studio based and NOT live, so please realize that this is not something I've dealt with in an "uncontrolled" environment.

[Donnie Frank]

A single Dynamic mic, particularly an SM58 is pretty much the worst option you could pick.

Okay....I was concerned with the proximity effect. Thanx for confirming.

I'd do two condensers configured in xy orientation or a set of LDC (You could even get away with a single Omni Directional Condensor, but you'll have to be careful about feedback.

According to sources, the chorus actually owns a pair of AKG 1000's. I assume they mean C1000's. Getting clarification on that. Assuming there's a pattern switch, can I assume that cardioid pattern would be best? It may have a switch for supercardioid. Might that be better?

Here's the mic I THINK they have:

http://www.akg.com/pro/p/c1000s

I'm not sure you need the floor monitor. If its an acapella group, it really doesn't serve any purpose as they should already be used to singing without a monitor and there wouldn't be any reason for them to be amplified on stage.

The guy hiring me insisted I provide one (they pay well). I can always turn it down or off. I have a feeling that they're not going to need a lot of volume. The room is a large church. I haven't been in the room, so I'm not sure the acoustics. I peaked through the glass and there's usual church fare with carpet. So maybe it won't be as live as most churches. Methinks the monitor might help with overcoming room slap or other acoustic anomalies.

When I've had to do choral groups I have a pair of AT2020's that I put up on boom stands, generally a couple of feet from each other, facing partially out L/R to cover the stage.

The AT2020 looks like a large diaphragm mic. Is that true?

I think I like the idea of an XY pattern with a pair of small diaphragm condensers set to a cardioid pattern.

Thoughts?

Thanx for your help.

Regards,

D

[cgrafx]

According to sources, the chorus actually owns a pair of AKG 1000's. I assume they mean C1000's. Getting clarification on that. Assuming there's a pattern switch, can I assume that cardioid pattern would be best? It may have a switch for supercardioid. Might that be better?

Here's the mic I THINK they have:

http://www.akg.com/pro/p/c1000s

Yes, set to Cardioid.

The guy hiring me insisted I provide one (they pay well). I can always turn it down or off. I have a feeling that they're not going to need a lot of volume. The room is a large church. I haven't been in the room, so I'm not sure the acoustics. I peaked through the glass and there's usual church fare with carpet. So maybe it won't be as live as most churches. Methinks the monitor might help with overcoming room slap or other acoustic anomalies.

If they need a monitor than fine, you'll just have to be careful about placement and volume.

The AT2020 looks like a large diaphragm mic. Is that true?

I think I like the idea of an XY pattern with a pair of small diaphragm condensers set to a cardioid pattern.

Yes, the 2020 is a large diaphragm mic. They are an amazingly nice mic, particularly given the price point. Around $100.

the C1000s could easily be used in an XY, but you'll need an adapter to hold the pair.

Something like show below.

[Angie]

You said this is a competition, right? Some will probably be just fine standing around an xy pair.
The C1000 is a great mic for this. They are cardioid (unless you use the hyper adapters which are easily lost anyway). You may also want to have a set of 58's at the ready. There may be some groups that will want hand-helds. Same with monitors. Some will want them, some won't care. You just have to be ready for all scenarios. Hopefully, you will have a decent soundcheck so that you can see beforehand what each group does.

Not that I would suggest you use them for this, but what makes you think you should avoid LDC? You've made similar statements before.

[cgrafx]

I don't believe proximity effect is limited to dynamic mics; rather it's a characteristic associated with a cardioid pattern on any mic.

Proximity effect is a change in the frequency response of a microphone, having a directional pickup pattern, that produces an emphasis on lower frequencies. It is caused by the use of ports to create directional polar pickup patterns, so omni-directional microphones do not exhibit the effect (it should be noted that this is not necessarily true of the "omni" pattern on multipattern condenser mics, which create the "omni" pattern by summing two back-to-back cardioid capsules, which may or may not share a common backplate.) Depending on the microphone design, proximity effect may result in a boost of up to 16 dB or more, depending on the size of the microphone's diaphragm and the distance of the source. A ready (and common) example of proximity effect can be observed with cardioid dynamic vocal microphones (though it is not limited to this class of microphone) when the vocalist is very close to or even touching the mic with their lips. The effect is heard as a 'fattening up' of the voice. Many radio broadcast microphones are large diameter cardioid pickup pattern microphones, and radio announcers are often observed to employ proximity effect, adding a sense of gravitas and depth to the voice. Proximity effect is sometimes referred to as "bass tip-up."^[2]

[Butch Bos]

Use the c1000s in a XY type setup but cross the mics so that the diaphragms are one on top of the other this will eliminate and phasing issues
You can adjust the angle to give the pickup angle you need
Then use 2 monitors with each having ONLY the opposite mic in it that will help the feedback problems
I have used this setup for many years doing sound for some great barbershop quartets
And do not forget to ring it out VERY well with people standing in the performers location (very important)
If you use SAC set the comps very heavy during the ring out process and then remember to take them off before the show
Short of giving them each a mic this will give the best results

Butch

[Donnie Frank]

Proximity effect is a change in the frequency response of a microphone, having a directional pickup pattern, that produces an emphasis on lower frequencies. It is caused by the use of ports to create directional polar pickup patterns, so omni-directional microphones do not exhibit the effect (it should be noted that this is not necessarily true of the "omni" pattern on multipattern condenser mics, which create the "omni" pattern by summing two back-to-back cardioid capsules, which may or may not share a common backplate.) Depending on the microphone design, proximity effect may result in a boost of up to 16 dB or more, depending on the size of the microphone's diaphragm and the distance of the source. A ready (and common) example of proximity effect can be observed with cardioid dynamic vocal microphones (though it is not limited to this class of microphone) when the vocalist is very close to or even touching the mic with their lips. The effect is heard as a 'fattening up' of the voice. Many radio broadcast microphones are large diameter cardioid pickup pattern microphones, and radio announcers are often observed to employ proximity effect, adding a sense of gravitas and depth to the voice. Proximity effect is sometimes referred to as "bass tip-up."^[2]

Thanx for the tutorial. I learned something today. Good stuff here!

Regards,

[Donnie Frank]

Use the c1000s in a XY type setup but cross the mics so that the diaphragms are one on top of the other this will eliminate and phasing issues
You can adjust the angle to give the pickup angle you need
Then use 2 monitors with each having ONLY the opposite mic in it that will help the feedback problems
I have used this setup for many years doing sound for some great barbershop quartets

Interesting. Just curious; Have you ever tried this setup with a single monitor? I don't mind setting up dual monitors if that's what needs to be done. But this isn't a large concert hall. It's a medium-sized church. I plan on using K8's for monitors, which have a very wide 105° dispersion angle. While, I agree that a single monitor wouldn't be exactly behind the cardioid lobe of either mic, it seems it would still be behind the mic's "enough" to minimize feedback issues. Thoughts?

And do not forget to ring it out VERY well with people standing in the performers location (very important)

This concerns me, as I usually like to fight feedback, first, with the physical placement of mic's, instruments, monitors, etc. And THEN toss E.Q. at it. But it sounds to me like you're describing a volatile feedback situation. The performers will be a good 3' in front of the mic's. Do they seriously act as reflectors at that distance?

Please understand that I'm not used to using cardioid mic's in a live sound reinforcement situation. So I'm not doubting your veracity. I just want to better understand the acoustic anomalies of the situation.

I'm going to have access to the mic's this Monday. I'll probably do some experimenting with them. I've never had problems with feedback before. But at this point, I'm now a little worried about it.

If you use SAC set the comps very heavy during the ring out process and then remember to take them off before the show

I assume you want me to do this to sort of "egg on" the feedback. Correct?

Short of giving them each a mic this will give the best results

Butch

Thank you, sir, for sharing your experience. Please forgive my questions.

Regards,