Recording lectures.

**Harpmaker** · **11-23-08, 09:09 AM**

I'm hoping to get some advice from folks who have experience with such things.

The situation is I have an old Zoom MRS-4 digital recorder (uses SmartMedia cards fer cryin' out loud!) and I need to record people speaking at a lectern, but they don't know how to use a mic (meaning they hold the thing at waist level). If I was just recording then I could simply boost the sound volume in post-production (I love digital audio!), but the signal is also going to a cheap Squire PA system.

My current setup is using a Shure SM-58 mic going into the PA and then sending the output to the recorder. From what little I know about microphones, the SM-58 is designed for singing, or talking with the mic close to the mouth. It worked okay the first time I used it, but I knew the sound volume should have been louder. As it is, I have to have the PA gain/volume controls set so they are on the verge of feedback.

Do I need a different mic, a mic pre-amp, or what?

Cost is an issue

since it's a non-paying gig (church group).

**Wayne A. Pflughaupt** · **11-23-08, 09:55 PM**

Since it's a lectern, how 'bout a screw-down mount with a gooseneck attached? That would work as long as they're staying put behind the lectern...

Lacking that, a parametric EQ could notch the feedback frequency and allow you to push the gain higher. You have a BFD in your home system, right?

Regards,
Wayne

**Harpmaker** · **11-23-08, 10:56 PM**

Quote:

Wayne A. Pflughaupt wrote:

Since it's a lectern, how 'bout a screw-down mount with a gooseneck attached? That would work as long as they're staying put behind the lectern...

Thanks Wayne.
I tried the whole stationary mic thing, but they want to either move around while behind the lectern (sometimes even standing beside it

), so that won't work too well. If it was just a single speaker I would think about going to a lavalier mic, but there are multiple speakers.

Quote:

Lacking that, a parametric EQ could notch the feedback frequency and allow you to push the gain higher. You have a BFD in your home system, right?

Regards,
Wayne

Sorry, I haven't gotten a Behringer Feedback Destroyer yet, although from looking at what this thing is supposed to do it might work for the purpose. Does it cut down a little or a lot on feedback? It almost sounds too good to be true.

**tenzip** · **11-24-08, 04:08 PM**

Maybe you can pick up a wireless lapel mic somewhere for not too much, that would solve most of your problems, as they wouldn't have to hold it, just talk. I know we rented one locally for a function at work, don't remember how much it was. No idea how much they cost, either. I know it had a wireless lapel mic, and a standard hand-held wireless mic, both feeding one receiver/mixer unit.

**tonyvdb** · **11-24-08, 09:34 PM**

Wireless lap is definatly the way to go. You can even get not only the transmitter battery operated but the receiver as well and they work well. I have a Telex Pro that has a 9v battery on each end and it lasts about 4 hrs on one battery has gain and level adjustments for ideal volume control.

**tenzip** · **11-25-08, 12:11 PM**

Sorry Don, for some reason I didn't make the connection between lavalier and lapel mic, but the system I'm thinking of would at least give you the flexibility of having a second hand held mic for other speakers, particularly if they are just speaking briefly.

Speaking from very little experience, it's quick to change from one person to another with the lapel mic, as long as you're not trying to run the wires inside shirts/blouses. The easiest way I found was to have the person wearing the mic take it off their shirt, hook it to the incoming speaker's shirt, remove the transmitter from their belt/waistband, and route the cord for the incoming speaker. Much faster and easier than having a person try to hook it to themselves.
Of course, the transmitter should be turned off or muted during this process, as it tends to be kind of loud if you leave it on.

If you are sitting somewhere that the speakers can see you while tending to the equipment, I suggest making a large sign saying MUTE, and hold it up to remind them when they are approaching the switch from one to another.

As for folks not holding the mic up to their mouth, there's really no cure besides standing behind them with a rolled-up piece of newspaper, and giving them a sharp whap in the back of the head when they let it drop. After a few whaps, the issue should be corrected.

Is the mic hooked up to a PA, or is it just for the recording?

**Harpmaker** · **11-25-08, 03:40 PM**

Quote:

tenzip wrote:

Sorry Don, for some reason I didn't make the connection between lavalier and lapel mic, but the system I'm thinking of would at least give you the flexibility of having a second hand held mic for other speakers, particularly if they are just speaking briefly.

No sweat, the common term is lapel mic; but I guess lavalier is more correct.

Quote:

If you are sitting somewhere that the speakers can see you while tending to the equipment, I suggest making a large sign saying MUTE, and hold it up to remind them when they are approaching the switch from one to another.

The problem is that besides their being multiple speakers, sometimes I don't even know who is going to be speaking since it's kind of a "whoever feels like saying a few words" thing. Changing lapel mics from user to user would be a real hassle; that's why I'm hoping to find another answer.

Quote:

As for folks not holding the mic up to their mouth, there's really no cure besides standing behind them with a rolled-up piece of newspaper, and giving them a sharp whap in the back of the head when they let it drop. After a few whaps, the issue should be corrected.

Oh man, don't tempt me!

Quote:

Is the mic hooked up to a PA, or is it just for the recording?

The mic is hooked to the PA.

**tonyvdb** · **11-25-08, 03:52 PM**

Its sounding like you must go with a podium mounted mic, there are many manufacturers of microphones out there that would do the job. Sure still makes one of the best the SM58 Another option is to get a good condenser microphone like the Sure SM81 as it being a condenser it will have a greater range and thus will pick up spoken word from a fair distance away. The drawback is that they can not be held and are poor if spoken into or blown into from less than 2" away.

**Wayne A. Pflughaupt** · **11-25-08, 05:24 PM**

Quote:

Harpmaker wrote:

Sorry, I haven't gotten a Behringer Feedback Destroyer yet, although from looking at what this thing is supposed to do it might work for the purpose. Does it cut down a little or a lot on feedback? It almost sounds too good to be true.

I only suggested the BFD on the chance you might have one, so it wouldn't cost a dime to take it out and use it. Ordinarily I prefer a more traditional equalizer.

Reading the other suggestions and your replies, it looks like podium mounting and lavs are out. Since it looks like you'll have to spend some money, I suggest a Rane PE15 parametric EQ. They're pretty cheap on eBay. I sold one a few years ago in pristine condition and got only $30-40 for it, IIR.

Basically, there's nothing like a parametric EQ for eliminating feedback. It's pretty easy, too. You can set it up before the show starts for a quiet, worry-free performance.

All you do is set the mic on a stand at the location you know will be the closest that the (human) speaker will ever get to the (PA) speaker. Slowly push the volume slider on the mixer up until feedback starts, then reduce the slider to stop it. Make a mental determination as to the general frequency range where the feedback is occurring. Typically it is the midrange and higher. As an audiophile you can tell a midrange feedback frequency from a high frequency one, right ?

Each filter on the Rane has a frequency operating range (say, 200Hz - 4000Hz, for instance). Select a filter that covers the range of the feedback you heard. Turn the bandwidth knob to the left for a tight setting, something like 1/6 to 1/10-octave. Also turn the gain knob to the left for a negative value, say -4 to -6 dB. Turn the frequency knob all the way to the top or bottom of the range - your choice.

Now, run the slider on the mixer up again to cause the feedback, only this time ride gain up and down to keep the offending frequency at a steady level (one that's non-damaging to both the system and your ears!). Then, sweep the frequency knob, "fishing" for the offending frequency. When you hit it, it will suck the feedback right out.

You will notice immediately that you will now be able to turn the volume slider on the mixer to a higher setting than you could before, before feedback starts.

If you think you need even more headroom, push the slider up some more to find the next ringing frequency, and repeat the exercise and eliminate that one, too. If instead you find that the first frequency starts feeding back again, all you have to do is increase the amount of cut a few more dB via the gain knob. Occasionally you'll find the second ringing frequency is right next to the first. In that case, just open up the bandwidth a bit, and you can catch both offending frequencies with the same filter.

I've use this technique to great success over the years. I used to do "kiddie theater" sound for the my kid's school - i.e., the Christmas, Easter programs, graduations, etc. It was murder getting some of the littlest kids to speak up - kindergartners, 1st, 2nd grade etc. Using my PE15 and the Shure SM 58 mics Tony mentioned, I could push the level of those mics to insane levels with no feedback, enough for the parents to hear their little darling's mumblings.

As far as the speakers not holding the mic correctly, the usual response from the sound man in this situation is (naturally) to turn the volume up to compensate for the drop in sound level, right? You might instead try a "reverse psychology" or "Pavlov's dogs" approach. As the speaker moves the mic away from his mouth, turn the volume down. When the audience starts complaining "we can't hear you," admonish the speaker to hold the mic closer to his mouth. When he does, "reward" him with audible sound. Of course, you will have to ride gain on the slider, turning it up and down with his hand movement to make it appear that he is indeed the cause of the problem. Repeat as needed. When the speaker gets tired of the audience complaining and/or interrupting him, he'll come around.

Regards,
Wayne

**ludwignew** · **11-25-08, 05:32 PM**

Why don't you try with a SM89. It has a hypercardioid pattern and could be useful to control distance and gain in mixer.

**tenzip** · **11-25-08, 05:38 PM**

Well, I haven't given up, here's some more suggestions for you. I see Wayne posted while I was typing, his suggestions sound pretty good to me.

First, do the speakers have any investment in having the lecture recorded? If not, you're fighting an uphill battle, I fear. If they do, get them together and explain the issues. Run down the options, and explain that the easiest/cheapest/quickest solution is for them to hold the mic up to their face. (Including the newspaper training option may or not be indicated, depending on the group, but could be used to get the point across.)
Cut the hook off of a clothes hanger, and bend the ends around the top and bottom of the mic, so that you have a triangle sticking out perpendicular to the axis of the mic, and tell the speakers to keep the point of the triangle on their breastbone. This will be a physical reminder of correct placement. Adjust the length of the wire to position correctly. Some electrical tape under and over the wires will keep them in place on the body of the mic.

**tenzip** · **11-25-08, 05:40 PM**

Quote:

Wayne A. Pflughaupt wrote:

As far as the speakers not holding the mic correctly, the usual response from the sound man in this situation is (naturally) to turn the volume up to compensate for the drop in sound level, right? You might instead try a "reverse psychology" or "Pavlov's dogs" approach. As the speaker moves the mic away from his mouth, turn the volume down. When the audience starts complaining "we can't hear you," admonish the speaker to hold the mic closer to his mouth. When he does, "reward" him with audible sound. Of course, you will have to ride gain on the slider, turning it up and down with his hand movement to make it appear that he is indeed the cause of the problem. Repeat as needed. When the speaker gets tired of the audience complaining and/or interrupting him, he'll come around.

I still like the newspaper.

**tonyvdb** · **11-25-08, 05:42 PM**

Wayne, would it not be cheaper to just get a 1/3 octave EQ and simply cut the frequencies that cause the issue? A parametric EQ has only a certain number of filters available to the user.

**Wayne A. Pflughaupt** · **11-25-08, 06:23 PM**

Cheaper than $50-60?

It's not hard to get a PE15 for that (okay, they seem to be getting a bit higher prices on eBay than when I sold mine

).

In my experience, a 1/3 octave EQ is not nearly as good for feedback control because it cuts too wide a path. To start, it can't precisely nail the offending frequency, only get close to it (unless perchance it is a perfect ISO frequency)! This means a more severe cut will be needed than if a parametric was used.

And remember, it's cutting 1/3-octave on both sides of the center frequency - 2/3 octaves total. That's introducing a pretty big hole just to hit a ringing note that can be nailed with a 1/10-octave or tighter filter. Multiply that wide path by the number of cuts you may have to make for additional feedback frequencies, and you're having a pretty devastating effect on overall frequency response, affecting far more than just the offending frequencies. With a parametric, you can notch offending frequencies with surgical precision, so much so that you can switch the filter in and out and hardly hear its effect at all. No way will a 1/3 EQ do that...

Sure, the parametric only has a few filters, but usually that's more than enough. Typically there will be only two or maybe three offending frequencies to get under control. If need be, the mixer itself can be used to "buy more mileage" from the parametric. Engaging its low pass filter and severly turning down the bass knob will take care of the entire bottom end, leaving more filters avalible. For voice, nothing below ~200 Hz is needed anyway. If there are other considerations in the system, like if music is played, the EQ can be inserted in the mic channel's signal chain and leave the rest of the system unequalized.

Regards,
Wayne

**tonyvdb** · **11-25-08, 07:15 PM**

Fully understand

**Harpmaker** · **11-26-08, 04:19 AM**

Thanks for all the feedback (pun intentional

) so far guys. So far the solutions seem to be around the $100 mark, which is doable, but close to the top end of my budget spectrum.

I would really like to stay with a hand-held mic if possible. The quality shotgun mics are just too expensive for me.

To reiterate, I am currently using a Shure SM58. I love the sound I get from the mic, I just wish it picked up sound at a farther distance from the person speaking than it does, but I guess it's designed not to.

Of the solutions so far (please keep them coming!), the Rane PE15 sounds like the one I would go with.

The room I'm recording in is beside the kitchen in a medium sized restaurant. Before we started using my PA system, I tried using a Radio Shack PZM/Boundary Layer mic, but it recorded EVERYTHING! Even the low bass thrum of the air conditioner system that was almost inaudible until it was recorded! Come to think of it, I bet the PE15 could help with that as well.

I'm not currently using a mixer, should I be? I've been looking at some, like the Behringer Eurorack UBB1002. Would this be a help or a hinderence in the long run?

The rest of this post will be quite boring, so I won't be offended if you stop reading now.

I got into this whole recording mess by accident. I wanted to record lectures without having to flip a cassette tape over every 30 or 45 minutes so I got my little Zoom MRS4 digital recorder. I started taking it to our church services because it was battery powered and I could hook it into the churches sound system with no trouble. The professional musician who was recording the services was having troubles with his equipment and several messages were lost from these hardware failures, I used my recorder as a backup. The guy showed me show to work the sound equipment (nothing fancy, just a portable Peavy PA system) just in case he couldn't be there. After about a year, the musician started his own music ministry and the church recording job fell to me kind of by default.

For reasons I won't go into, the church ending up folding and was no more, but about half the people still get together 4 or 5 times a year for fellowship and Bible study. These meetings are what I'm currently recording.

**Wayne A. Pflughaupt** · **11-26-08, 07:27 PM**

Quote:

I'm not currently using a mixer, should I be? I've been looking at some, like the Behringer Eurorack UBB1002.

Unless you have a powered speaker like a JBL Eon that will accept a direct mic input, you're using a mixer. Sounds like it's your portable Peavy system...

Regards,
Wayne

**Harpmaker** · **11-26-08, 07:56 PM**

Quote:

Wayne A. Pflughaupt wrote:

Unless you have a powered speaker like a JBL Eon that will accept a direct mic input, you're using a mixer. Sounds like it's your portable Peavy system...

Regards,
Wayne

OK, gotcha.

I wish I was using that Peavey system (a 150 watt Peavey Escort 2000), it worked great and was very portable. I'm now using a 'Squier by Fender 4-Channel PA System' (shown below) that is only 80 watts and it is barely cutting the mustard.

**Wayne A. Pflughaupt** · **11-26-08, 08:32 PM**

Hmm... You'd think it would be enough for just vocal support, even in that restaurant. If you're running out of headroom, you might try reducing the bass control. As I mentioned, you don't need anything below ~200 Hz for voices. Excessive bass on voices not only makes them sound boomy and unnatural, it also wastes power.

Regards,
Wayne

**Harpmaker** · **11-26-08, 11:47 PM**

Quote:

Wayne A. Pflughaupt wrote:

Hmm... You'd think it would be enough for just vocal support, even in that restaurant. If you're running out of headroom, you might try reducing the bass control. As I mentioned, you don't need anything below ~200 Hz for voices. Excessive bass on voices not only makes them sound boomy and unnatural, it also wastes power.

Regards,
Wayne

I would be enough if they would just talk into the mic.

I'll try again to get that point across.

Maybe I'm misremembering, but I think I cut down on the treble to decrease the feedback problem.

And you are correct, there is no music involved; just voice.

**drf** · **12-01-08, 03:43 AM**

Heres a thought I'd like to throw into the mix, Have you considered a shotgun video mic? I have seen them used effectively for highschool theatre, where the students can't stand still or know how to use a mic.

**tweeksound** · **12-01-08, 09:07 AM**

Sorry, I only read about half the posts so if I repeat something, I apologize.

You could try making sure the speaker is far behind the amp. Push the speaker (podium) back a little and/or pull the amp front a bit.
The further from the amp, the less sound is fed back.

Also, make sure your amp is set as clean as possible. Turn main volume all the way up and the gain all the way down and then start bringing the gain up until it's loud enough.

Have any built in EQ set to 0 boost/cut, unless you're using a feedback cut.

I record lectures full time for AM and FM radio and I am a film/video sound recording mixer/boom operator so I have run into just about every problem you can imagine trying to get good dialog.

For my recordings I use an SM81 but a condenser like that will exacerbate your feedback issue when fed through an amp. A lapel can be the best bet if they are an animated speaker.

Sometimes you just have to talk to the speakers and let them know that unless they use good mic technique, the sound will suffer and the audience may not hear them. If they are speaking in front of an audience, they most likely want to be heard so they will probably work with you.

**tweeksound** · **12-01-08, 09:11 AM**

I see that your amp is a PA system. I thought you were using a Squire guitar amp! Sorry, the gain vs master comment is not applicable then.

I've had lots of folks trying to use guitar amps as PA amps (bad idea) but it can at least be maximized for the best sound, but then again, so could a tin can!

**Harpmaker** · **12-01-08, 10:51 AM**

drf,
Interestingly enough, I purchased a Audio-Technica ATR 55 Uni-Directional Condenser Shotgun Microphone (see photo below) about a year ago. It does double-duty on by my old Sony Digital8 camcorder and as a recording mic when hooked to my Zoom MRS4 voice recorder. Back when we were using the restaurants built-in wireless PA (the sound was truly horrible, and then they started charging for it's use) I got great recordings using the ATR-55 directly into the Zoom; it honestly sounded like a good lapel mic (at least to my ears). I positioned it about 6 feet from the lectern. The problem is I can't get enough volume out of it when hooked to the PA system; that may be associated with it being an unbalanced input.

Matt,
Thanks for the tips. Yep, it's a cheap PA not a cheap guitar amp.

Something I'm really having a problem with is understanding microphones. I get the difference (I think) between directional mics vs handheld mics; but then I get lost. How do you know if a mic is designed to be used with the lips almost in contact with the mic and one designed to pick up a group of singers? Dynamic vs condenser; large diaphragm vs small diamphram? Sorry to be so dumb about this stuff, but I am trying to learn.

You are the second person to recommend a SM81, but Tony said they can't be handheld (I assume because they pick up handling noise). In case anyone missed it, I'm currently using a SM58.

Another issue that I don't understand is that when I hooked my SM58 up to my PA using an XLR-1/4" adapter the volume level dropped significantly and I got hum (I did this just as a test since the PA has both kinds of inputs, an adapter cable came with the amp). Would I get better performance from a mic such as the ATR55 above if I used an adapter to plug it into an XLR input?

Sorry for the long posts and dumb questions. I seriously appreciate the help!

**tonyvdb** · **12-01-08, 12:15 PM**

Quote:

Harpmaker wrote:

Something I'm really having a problem with is understanding microphones. I get the difference (I think) between directional mics vs handheld mics; but then I get lost. How do you know if a mic is designed to be used with the lips almost in contact with the mic and one designed to pick up a group of singers? Dynamic vs condenser; large diaphragm vs small diamphram? Sorry to be so dumb about this stuff, but I am trying to learn.

Here is some of the microphones you will find,
Cardioid (hand held microphone like the SM58)
Omni-directional (Picks up sound from all around the micorphone)
Super Cardioid
Hyper Cardioid (both the Super and Hyper mics are more sensitive and good for insterment pickup or choir)
Figure 8 (not a common one but picks up sound from in front and befind the mic but not from the sides)

An even more detailed look can be found here

Quote:

You are the second person to recommend a SM81, but Tony said they can't be handheld (I assume because they pick up handling noise). In case anyone missed it, I'm currently using a SM58.

Yes that is correct, they would pick up the handling noise unless held very carefully. But they have a gain control as well as a three position High Pass filter built in.

Quote:

Another issue that I don't understand is that when I hooked my SM58 up to my PA using an XLR-1/4" adapter the volume level dropped significantly and I got hum (I did this just as a test since the PA has both kinds of inputs, an adapter cable came with the amp). Would I get better performance from a mic such as the ATR55 above if I used an adapter to plug it into an XLR input?

If your not using a proper transformer box known as a direct box or DI Box to convert the XLR to 1/4" you will loose gain and pick up allot of noise.

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