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Title: Help needed making microphones more sensitive
Post by: Cameron Peck on May 21, 2019, 03:24:47 pm
Our organization holds meetings in hotel banquet rooms 3 times per year and I got tired of paying their outrageous prices to rent audio equipment. So, I purchased the equipment below to help us save money. We use the house sound system but with our equipment.

2 X Shure SM57 microphones
1 x Behringer Micromix MX400 Ultra Low-Noise 4-Channel Line Mixer
1 X Peavey USB Audio Interface
1 X Behringer MicroHD HD400 Ultra-Compact 2-Channel Hum Destroyer

I purchased the mics based solely on the fact that is has been used for the Presidental Podium for 30 years.

The mics don't seem to be sensitive enough for our needs. The 1st time we used this setup, we had to turn up the volume so high that the hum was unbearable. We just ended up not using mics and everyone had to speak loudly. (This is also why we purchased the Hum Destroyer)

This last time, the volume wouldn't go loud enough to be useable without holding the mic very close to the mouth (which is not a good solution when trying to do presentations). So, we had to rent the mics from the hotel.

Can you help me find a good (and cost effective) way to use our current mics but louder? If not, what do we need to change? Also, hauling around our own powered speakers is not an option.
Title: Re: Help needed making microphones more sensitive
Post by: Corey Scogin on May 21, 2019, 03:44:10 pm
Our organization holds meetings in hotel banquet rooms 3 times per year and I got tired of paying their outrageous prices to rent audio equipment. So, I purchased the equipment below to help us save money. We use the house sound system but with our equipment.

2 X Shure SM57 microphones
1 x Behringer Micromix MX400 Ultra Low-Noise 4-Channel Line Mixer
1 X Peavey USB Audio Interface
1 X Behringer MicroHD HD400 Ultra-Compact 2-Channel Hum Destroyer

You need a preamp (or mixer with preamps) with balanced inputs. The Behringer MX400 is an unbalanced line-level mixer, there are no microphone preamps in it. If you get a simple, cheap mixer, such as the Behringer Xenyx 802 (https://www.sweetwater.com/store/detail/802--behringer-xenyx-802-mixer), you should not need the "Hum Destroyer" as the balanced lines should eliminate any hum picked up on the cabling. Also use balanced output cables (Tip-Ring-Sleeve 1/4" cables or XLR cables) to connect to the sound system.

Edit: PS:
I didn't notice that you aren't using your real name. Please change your username to your real first and last name before the moderators lock this thread.
Mods: sorry for responding without checking.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 21, 2019, 04:41:25 pm
You need a preamp (or mixer with preamps) with balanced inputs. The Behringer MX400 is an unbalanced line-level mixer, there are no microphone preamps in it. If you get a simple, cheap mixer, such as the Behringer Xenyx 802 (https://www.sweetwater.com/store/detail/802--behringer-xenyx-802-mixer), you should not need the "Hum Destroyer" as the balanced lines should eliminate any hum picked up on the cabling. Also use balanced output cables (Tip-Ring-Sleeve 1/4" cables or XLR cables) to connect to the sound system.

Edit: PS:
I didn't notice that you aren't using your real name. Please change your username to your real first and last name before the moderators lock this thread.
Mods: sorry for responding without checking.

Thanks for your information.  It looks like I was not using the correct type of mixer.  Will the 802 allow me to use the mics from further away, rather than having to hold it right in my face?
Title: Re: Help needed making microphones more sensitive
Post by: David Sturzenbecher on May 21, 2019, 04:46:33 pm


I purchased the mics based solely on the fact that is has been used for the Presidental Podium for 30 years.



Fun Fact, if you have seen a SM57 on a presidential podium in recent years, there is a very good chance it was a modified (upgraded) mic with much higher end components.

A mixer with a proper microphone preamp should allow you to get much more gain.   But I do predict that you will be posting again asking how to eliminate the feedback being created by your new mixer.
Title: Re: Help needed making microphones more sensitive
Post by: Mike Caldwell on May 21, 2019, 04:50:07 pm
Thanks for your information.  It looks like I was not using the correct type of mixer.  Will the 802 allow me to use the mics from further away, rather than having to hold it right in my face?

That will let you apply more gain to the mic and pick up sound a little further away from the mic.
That said there are a lot of other factors you will need to deal with once to start putting the mic into a sound system and want to bring the level up to where people will hear it.

Title: Re: Help needed making microphones more sensitive
Post by: John P. Farrell on May 21, 2019, 04:52:57 pm
Thanks for your information.  It looks like I was not using the correct type of mixer.  Will the 802 allow me to use the mics from further away, rather than having to hold it right in my face?

57's can do pretty much anything.....maybe not the first choice for the job but far from the worst. 

With that being said, what do you normally rent from the hotel?  You've been trying to plug microphones into a line level mixer.  If you're trying to replace a lavaliere with an SM57 you'll probably be disappointed.  If you're looking for a lectern mic or a table top mic you'll probably be fine if you do a little reading on gain structure and EQ. 
Title: Re: Help needed making microphones more sensitive
Post by: Corey Scogin on May 21, 2019, 05:38:37 pm
This last time, the volume wouldn't go loud enough to be useable without holding the mic very close to the mouth (which is not a good solution when trying to do presentations). So, we had to rent the mics from the hotel.

Side note: the closer you get the microphone to the sound source you want it to pick up, the less gain is required and the less feedback you'll get. Often (not always) closer = better sound as well.
Title: Re: Help needed making microphones more sensitive
Post by: Tim Weaver on May 21, 2019, 05:56:56 pm
We have a saying around here. "the loudest sound at the mic wins". Just keep repeating that to yourself while setting up next time.
Title: Re: Help needed making microphones more sensitive
Post by: Jason Glass on May 21, 2019, 06:48:29 pm
Our organization holds meetings in hotel banquet rooms 3 times per year and I got tired of paying their outrageous prices to rent audio equipment. So, I purchased the equipment below to help us save money. We use the house sound system but with our equipment.

2 X Shure SM57 microphones
1 x Behringer Micromix MX400 Ultra Low-Noise 4-Channel Line Mixer
1 X Peavey USB Audio Interface
1 X Behringer MicroHD HD400 Ultra-Compact 2-Channel Hum Destroyer

I purchased the mics based solely on the fact that is has been used for the Presidental Podium for 30 years.

The mics don't seem to be sensitive enough for our needs. The 1st time we used this setup, we had to turn up the volume so high that the hum was unbearable. We just ended up not using mics and everyone had to speak loudly. (This is also why we purchased the Hum Destroyer)

This last time, the volume wouldn't go loud enough to be useable without holding the mic very close to the mouth (which is not a good solution when trying to do presentations). So, we had to rent the mics from the hotel.

Can you help me find a good (and cost effective) way to use our current mics but louder? If not, what do we need to change? Also, hauling around our own powered speakers is not an option.
Mr. Peck,

I do wish you good luck and commend your willingness to learn audio engineering from the ground up.

It seems that you've been given the opportunity to learn that what you were paying for was not equipment.  It was the unique expertise of an audio engineer.

We know how to select, deploy, and operate the right equipment to deliver a desirable result.  Even the guy at the hotel does.  If he makes it look too easy to be worth your $, then he's undoubtedly worth multiples of what a hotel pays him.  And he doesn't need to be the person riding the faders during your event to have earned it.  His efforts that result in a system that can be satisfactorily operated by a novice may not be obvious, but they're precious.

The answers here are excellent, but  nothing delivers professional results like an appropriately paid audio professional.  Believe me when I tell you that once you achieve the mic sensitivity that you desire, routed to an appropriate amount of amplification, your problems with audio will have only just begun!  You can learn this trade, no doubt.  But taking the bigger lesson here to heart will make you a better manager who puts on a better show.

Sent from my mobile phone using Tapatalk
Title: Re: Help needed making microphones more sensitive
Post by: duane massey on May 21, 2019, 07:03:54 pm
I would suggest (at the very least) that you hire someone to tell you what to buy and show you how to set it up.
Title: Re: Help needed making microphones more sensitive
Post by: Don T. Williams on May 21, 2019, 07:45:45 pm
As with most things, it will only work as well as the weakest link allows.  Though not universally true, most hotel ballrooms/conference rooms typically have pretty low quality loudspeakers, usually installed ceiling mount type.  This makes getting very high quality sound tough.  As has been stated, getting the mics as close to the presenter, will help immensely.  In an interview, a very well know corporate event engineer was ask " what is your most important tool for getting quality vocals"?  He replied " I have a large sigh I hold up that says " get closer to the mic"".
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 21, 2019, 08:11:01 pm
Fun Fact, if you have seen a SM57 on a presidential podium in recent years, there is a very good chance it was a modified (upgraded) mic with much higher end components.
That is funny.  Oh well.


A mixer with a proper microphone preamp should allow you to get much more gain.   But I do predict that you will be posting again asking how to eliminate the feedback being created by your new mixer.
Would different microphones (in addition to adding a mixer w/ preamps) be a better solution?  I want to learn.  My ultimate goal is to provide good sound for the spoken voice with as little trouble as possible (while still doing it myself).
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 21, 2019, 08:16:51 pm
Mr. Peck,

I do wish you good luck and commend your willingness to learn audio engineering from the ground up.

It seems that you've been given the opportunity to learn that what you were paying for was not equipment.  It was the unique expertise of an audio engineer.

We know how to select, deploy, and operate the right equipment to deliver a desirable result.  Even the guy at the hotel does.  If he makes it look too easy to be worth your $, then he's undoubtedly worth multiples of what a hotel pays him.  And he doesn't need to be the person riding the faders during your event to have earned it.  His efforts that result in a system that can be satisfactorily operated by a novice may not be obvious, but they're precious.

The answers here are excellent, but nothing delivers professional results like an appropriately paid audio professional.  Believe me when I tell you that once you achieve the mic sensitivity that you desire, routed to an appropriate amount of amplification, your problems with audio will have only just begun!  You can learn this trade, no doubt.  But taking the bigger lesson here to heart will make you a better manager who puts on a better show.

I know that you are correct.  Please do not think that I am belittling what audio pros do.  I admire the people in the trade, it cannot be easy to get everything working just right, no doubt.  The organization has a pretty tight budget and I am just trying to be frugal where I can.  No harm intended.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 21, 2019, 08:20:42 pm
If you get a simple, cheap mixer, such as the Behringer Xenyx 802 (https://www.sweetwater.com/store/detail/802--behringer-xenyx-802-mixer)...

That sounded familiar, so I looked in my basement and realized that I had a Eurorack UB802 that I purchased for a project 10 years ago and never used.  It appears to be the predecessor to the Xenyx 802.  Is there any reason this will not work?
Title: Re: Help needed making microphones more sensitive
Post by: duane massey on May 22, 2019, 12:54:29 am
UB802 only has 2 mic inputs, but if that is enough it would (technically) work.
Title: Re: Help needed making microphones more sensitive
Post by: Corey Scogin on May 22, 2019, 01:06:48 am
Would different microphones (in addition to adding a mixer w/ preamps) be a better solution?  I want to learn.  My ultimate goal is to provide good sound for the spoken voice with as little trouble as possible (while still doing it myself).

Different microphones will provide minimal improvement over the SM57. Are there better microphones for this purpose? Sure, but I'd focus on just getting your gain structure right first.

That sounded familiar, so I looked in my basement and realized that I had a Eurorack UB802 that I purchased for a project 10 years ago and never used.  It appears to be the predecessor to the Xenyx 802.  Is there any reason this will not work?

That appears to be exactly the same thing as the Xenyx 802. Anything with microphone preamps will work to get you started.

Make sure the Main Mix level is down all the way then start by setting the channel gains to somewhere between 10:00 and 12:00. Make sure the channel peak lights do not light up when speaking loudly into the microphone.
Next, turn up the channel levels and main mix level as needed.

There's a way to set the gains more accurately on that mixer but I didn't want to distract from just getting it working.

One question...
How do you connect to the hotel sound system?
When you rented the hotel mics, did they plug in directly to the same place you plan to plug in the output of your mixer?

The reason I ask is that the output from any microphone is orders of magnitude less than the typical output from a mixer. You may still have some issues but they'll be on the opposite end of the gain problem if the only input to the PA available is one set up for a microphone.

Title: Help needed making microphones more sensitive
Post by: Scott Olewiler on May 22, 2019, 08:06:52 am


One question...
How do you connect to the hotel sound system?
When you rented the hotel mics, did they plug in directly to the same place you plan to plug in the output of your mixer?

The reason I ask is that the output from any microphone is orders of magnitude less than the typical output from a mixer. You may still have some issues but they'll be on the opposite end of the gain problem if the only input to the PA available is one set up for a microphone.

Corey has just asked probably the most important question on this.

Knowing exactly where you're interfacing with the hotel system is going to be crucial to getting more detailed help from this forum. If it's just jack in a wall plate, you'll  need to find out where that jack connects on the other end.  Knowing whether your mixer output goes into another mixer input down the line (and whether it is a line level input or a microphone input) or an amp input, and whether or not there are upstream gain controls that may not be at the correct level for whatever you're sending determines the correct solution to your problem.



Sent from my iPad using Tapatalk
Title: Re: Help needed making microphones more sensitive
Post by: John Halliburton on May 22, 2019, 09:53:33 am
Sure, but I'd focus on just getting your gain structure right first.

Make sure the channel peak lights do not light up when speaking loudly into the microphone.
Next, turn up the channel levels and main mix level as needed.


One question...
How do you connect to the hotel sound system?
When you rented the hotel mics, did they plug in directly to the same place you plan to plug in the output of your mixer?

The reason I ask is that the output from any microphone is orders of magnitude less than the typical output from a mixer. You may still have some issues but they'll be on the opposite end of the gain problem if the only input to the PA available is one set up for a microphone.

Gain structure AND having the right equipment.  As you noted earlier, the difference between a line mixer and a mic mixer is significant.

As for setting the initial gain on a channel, one method used on gear with only a peak LED was to "bark" into the mic, adjust the trim until the peak light comes on during the loudest sound, then dial it back a bit.

And I'm also interested in how the OP patches into the hotel system, there may still be some issues at that point.

Best regards,

John

Title: Re: Help needed making microphones more sensitive
Post by: Scott Helmke on May 22, 2019, 10:07:46 am
So this sounds a lot like the "I'm an IT manager so they told me to fix the sound" thing I run into a lot these days.

Good news - Shure has some education content about the basics that might be very helpful in understanding the situation better.
https://www.shure.com/en-US/videos/events/webinars/shure-webinar-audio-basics-for-it-professionals
Title: Re: Help needed making microphones more sensitive
Post by: Frank Czar on May 22, 2019, 10:39:57 am
I have a question and a suggestion for you.

The question is how are you using the SM-57's, as the President does, dual mics - one person speaking or are you using them as two separate sources?  I actually do not know if that is how the Presidents audio crew is utilizing the 2 mics, one mic may be there for redundancy. I believe though you will get better results with 1 mic, if you are trying to use two mics on one person, one mic would need to switched out of phase and a lot more tweaking would be needed than a single mic.

Everyone else is correct in stating you must know what you are connecting to in the hotel. You may want to consider purchasing a set of powered speakers. This way you always know what you are plugging your mixer into and it will give you a chance to set it up at home and gain some experience learning how things all work, maybe volunteer your services for an event where the sound is not crucial, like a family party or something like that.

Good Luck
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 22, 2019, 12:44:10 pm
Make sure the Main Mix level is down all the way then start by setting the channel gains to somewhere between 10:00 and 12:00. Make sure the channel peak lights do not light up when speaking loudly into the microphone.
Next, turn up the channel levels and main mix level as needed.
Thank you, this is very helpful.


How do you connect to the hotel sound system?
When you rented the hotel mics, did they plug in directly to the same place you plan to plug in the output of your mixer?
Yes, we only changed the mic, everything else was left the same.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 22, 2019, 12:51:44 pm
Corey has just asked probably the most important question on this.

Knowing exactly where you're interfacing with the hotel system is going to be crucial to getting more detailed help from this forum. If it's just jack in a wall plate, you'll  need to find out where that jack connects on the other end.  Knowing whether your mixer output goes into another mixer input down the line (and whether it is a line level input or a microphone input) or an amp input, and whether or not there are upstream gain controls that may not be at the correct level for whatever you're sending determines the correct solution to your problem.
Luckily, I have a good relationship with the event coordinators, so I can make arrangements to "peek behind the curtain".  On a side note, the hotel we just use had 2 XLR connections (one directly above the other).  Is there an industry standard that might explain the difference between them?
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 22, 2019, 12:53:10 pm
So this sounds a lot like the "I'm an IT manager so they told me to fix the sound" thing I run into a lot these days.

Good news - Shure has some education content about the basics that might be very helpful in understanding the situation better.
https://www.shure.com/en-US/videos/events/webinars/shure-webinar-audio-basics-for-it-professionals

That was helpful.  Thank you for pointing it out to me.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 22, 2019, 12:57:52 pm
I have a question and a suggestion for you.

The question is how are you using the SM-57's, as the President does, dual mics - one person speaking or are you using them as two separate sources?  I actually do not know if that is how the Presidents audio crew is utilizing the 2 mics, one mic may be there for redundancy. I believe though you will get better results with 1 mic, if you are trying to use two mics on one person, one mic would need to switched out of phase and a lot more tweaking would be needed than a single mic.
Good question.  One mic is on the podium for the presenter and the other one is in a mic stand on the floor for questions and or comments from the audience.


Everyone else is correct in stating you must know what you are connecting to in the hotel. You may want to consider purchasing a set of powered speakers. This way you always know what you are plugging your mixer into and it will give you a chance to set it up at home and gain some experience learning how things all work, maybe volunteer your services for an event where the sound is not crucial, like a family party or something like that.

Good Luck

That is a good idea, but we cannot do that for several reasons.  House speakers are our only option other than renting powered speakers from the hotel.
Title: Re: Help needed making microphones more sensitive
Post by: drew gandy on May 22, 2019, 05:18:18 pm
I'll join the fun!  [It's not often that we get beginners here so early and untainted.  A little bit of bad audio knowledge can go a looong way!]

I fully understand your issue with the cost of hotel AV.  Keep in mind that AV is a revenue stream for the hotel and they may very well be taking 50% off the top of the bill that the in-house AV company is charging.  Like a fledgling band in LA, hotel AV is a pay to play game.   You may be able to convince the hotel to give you a break on their take of the AV bill. 

When you plug your mixer into the hotel installed sound system, a tell tale sign that it is a "microphone level" input is that you will immediately hear a hiss even when your mixer output level is turned all the way down.  And once you try to turn your output level up, all kinds of chaos will ensue.  An inline pad connected between your mixer and the hotel XLR jack might make it usable.  What this does is to turn the output signal from your mixer down a bit which lowers the noise and makes your controls on your mixer far more usable. 
https://www.bhphotovideo.com/c/product/351406-REG/Whirlwind_IMPAD20_IMPAD20_In_Line_XLR.html

Just for fun:
A)  Make sure all your cables just barely reach to wherever they are going and only reach when you run them across the middle of the floor "as the crow flies". 

B)  When you're buying economy equipment, watch out for "High Grade Low Noise Microphone Cable", especially if you ever buy condenser microphones.  (see image below) My example is of a microphone cable that is entirely missing one of the conductors.  Short of opening the connector up like I did, you wouldn't be any the wiser except that you get no signal or noisy signal when you use it.

C)  Don't forget to use the brightest orange extension cords you can find.   

 ;D






Title: Re: Help needed making microphones more sensitive
Post by: Scott Holtzman on May 22, 2019, 05:59:55 pm
I'll join the fun!  [It's not often that we get beginners here so early and untainted.  A little bit of bad audio knowledge can go a looong way!]

I fully understand your issue with the cost of hotel AV.  Keep in mind that AV is a revenue stream for the hotel and they may very well be taking 50% off the top of the bill that the in-house AV company is charging.  Like a fledgling band in LA, hotel AV is a pay to play game.   You may be able to convince the hotel to give you a break on their take of the AV bill. 

When you plug your mixer into the hotel installed sound system, a tell tale sign that it is a "microphone level" input is that you will immediately hear a hiss even when your mixer output level is turned all the way down.  And once you try to turn your output level up, all kinds of chaos will ensue.  An inline pad connected between your mixer and the hotel XLR jack might make it usable.  What this does is to turn the output signal from your mixer down a bit which lowers the noise and makes your controls on your mixer far more usable. 
https://www.bhphotovideo.com/c/product/351406-REG/Whirlwind_IMPAD20_IMPAD20_In_Line_XLR.html

Just for fun:
A)  Make sure all your cables just barely reach to wherever they are going and only reach when you run them across the middle of the floor "as the crow flies". 

B)  When you're buying economy equipment, watch out for "High Grade Low Noise Microphone Cable", especially if you ever buy condenser microphones.  (see image below) My example is of a microphone cable that is entirely missing one of the conductors.  Short of opening the connector up like I did, you wouldn't be any the wiser except that you get no signal or noisy signal when you use it.

C)  Don't forget to use the brightest orange extension cords you can find.   

 ;D

I hope you know he is kidding
Title: Re: Help needed making microphones more sensitive
Post by: frank kayser on May 22, 2019, 06:14:28 pm
<snip>
The answers here are excellent, but  nothing delivers professional results like an appropriately paid audio professional.

Sent from my mobile phone using Tapatalk


Huh.  If I raise my rates, my results will be more professional. Who'da thunk? ;D  (at least the resulting  invoice will look more professional!)
Also, does it follow that a poor quality audio professional barely scraping by (appropriate pay) will provide similar professional results?  ::)


Sorry.  Just having fun.  I'm sure everyone knew exactly what you were communicating. 


Please return to the normal, helpful discussion.
Title: Re: Help needed making microphones more sensitive
Post by: Mike Caldwell on May 22, 2019, 08:05:07 pm
I'm not knocking your spirit and willingness to jump into this and want to learn but corporate meeting gigs even your smaller ones are not what I would consider the place to figure out how to do audio for the first time.

You said you do three events a year, hire in a legit AV company, help them were you can, pick up some experience and maybe even do some freelance work for them if it opportunity comes up.
Title: Re: Help needed making microphones more sensitive
Post by: Patrick Tracy on May 23, 2019, 12:55:16 am
Our organization holds meetings in hotel banquet rooms 3 times per year and I got tired of paying their outrageous prices to rent audio equipment.

Where are you located? Perhaps someone on the forum would be willing to spend a compensated hour or two to get you going.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 23, 2019, 10:06:49 am
Everyone has been very helpful to me and I appreciate it very much.  Especially, Corey Scogin.



When you plug your mixer into the hotel installed sound system, a tell tale sign that it is a "microphone level" input is that you will immediately hear a hiss even when your mixer output level is turned all the way down.  And once you try to turn your output level up, all kinds of chaos will ensue.  An inline pad connected between your mixer and the hotel XLR jack might make it usable.  What this does is to turn the output signal from your mixer down a bit which lowers the noise and makes your controls on your mixer far more usable. 
https://www.bhphotovideo.com/c/product/351406-REG/Whirlwind_IMPAD20_IMPAD20_In_Line_XLR.html
That got me thinking and I went back and looked at an email that I received before one of the events.  It said, "Our ballroom has XLR inputs for a mic level signal."  At the time, I didn't realize that mic level and line level were different, so the info that I was given was not as useful then as it will be when we go back there in December.

Seeing that it was a mic level input and I was using a mic without a mic preamp, shouldn't it have worked better?  I was still going through the MX400.  Either way, it sounds like I will need to use a pad (in addition to the mixer) the next time we are at that hotel.

On a side note, at the hotel we use most of the time, I don't believe they have an audio pro.  It is always the servers that are working with the audio.
Title: Re: Help needed making microphones more sensitive
Post by: Corey Scogin on May 23, 2019, 11:34:04 am
Seeing that it was a mic level input and I was using a mic without a mic preamp, shouldn't it have worked better?  I was still going through the MX400.

The sensitivity of a microphone -- how much voltage it outputs for a given Sound Pressure Level input -- varies considerably between dynamic and condenser mics and can also vary quite a bit between different models of the same type of mic. More sensitive does not mean better. The SM57s may just be less sensitive than the mics they'd set it up for.

The MX400 may have been causing some of the noise.

  Either way, it sounds like I will need to use a pad (in addition to the mixer) the next time we are at that hotel.

I'd recommend a -20dB pad. If you happen to have a passive DI with a pad on it, that should work also.
Title: Re: Help needed making microphones more sensitive
Post by: Patrick Tracy on May 23, 2019, 02:12:42 pm
Seeing that it was a mic level input and I was using a mic without a mic preamp, shouldn't it have worked better?

Microphones produce very small voltages from the sound they capture. That signal has to be transmitted to the mic preamp carefully or it can pick up all kinds of noise. The low impedance balanced connection is designed for that. Connecting to the Micromix defeats the system for ensuring proper transmission of the mix signal to the mic preamp. That's how the noise got into the signal.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 23, 2019, 02:49:39 pm
Microphones produce very small voltages from the sound they capture. That signal has to be transmitted to the mic preamp carefully or it can pick up all kinds of noise. The low impedance balanced connection is designed for that. Connecting to the Micromix defeats the system for ensuring proper transmission of the mix signal to the mic preamp. That's how the noise got into the signal.
I understand.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on May 23, 2019, 02:51:54 pm
Thanks, everyone.  I plan on taking the equipment to the hotel that we are using next and do a trial run ahead of time.  I will report back with how it goes.  You all are awesome!
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on June 24, 2019, 10:59:00 am
***UPDATE***

I took the equipment to the hotel on Friday and tried it out.  Replacing the MX400 with the UB802 worked as expected.  And thank you to Drew for suggesting the PAD, I needed it.  Everything appears to be working properly now.

Of course, this was only a short test in an environment that was not exact to what we will have, but I believe I am far better off than I was before I asked the question on here.  Thank you all for your help.  I will report back after the actual event.
Title: Re: Help needed making microphones more sensitive
Post by: Cameron Peck on July 23, 2019, 09:32:28 am
We had our meeting last weekend and the sound was great.  Thank you, everyone, for your help.
Title: Re: Help needed making microphones more sensitive
Post by: Steve Ferreira on July 23, 2019, 09:57:34 am
Glad to hear it worked out for you Cameron.
Title: Re: Help needed making microphones more sensitive
Post by: Jordan Wolf on July 25, 2019, 08:46:30 pm
We had our meeting last weekend and the sound was great.  Thank you, everyone, for your help.
Awesome! Glad to hear things worked out well for you.
Title: Re: Help needed making microphones more sensitive
Post by: Matthias McCready on July 26, 2019, 09:24:32 am
I have a question and a suggestion for you.

The question is how are you using the SM-57's, as the President does, dual mics - one person speaking or are you using them as two separate sources?  I actually do not know if that is how the Presidents audio crew is utilizing the 2 mics, one mic may be there for redundancy. I believe though you will get better results with 1 mic, if you are trying to use two mics on one person, one mic would need to switched out of phase and a lot more tweaking would be needed than a single mic.


The 2nd mic is simply there for redundancy, and they prefer it if it is kept the same level as the live mic to be unmuted should problems arise. For obvious reasons, you cannot place a wireless pack on the president (or VP). So dual SM57's it is.
Title: Re: Help needed making microphones more sensitive
Post by: Alec Spence on July 26, 2019, 11:33:56 am
I purchased the mics based solely on the fact that is has been used for the Presidental Podium for 30 years.
Head... in... hands...
Title: Re: Help needed making microphones more sensitive
Post by: Tim McCulloch on July 26, 2019, 11:52:30 am
Head... in... hands...
There are worse reasons, Alec.

Like Chris Hindle's sig line says "Just put a 57 on it and get off my stage."
Title: Re: Help needed making microphones more sensitive
Post by: Chris Hindle on July 26, 2019, 12:22:20 pm
There are worse reasons, Alec.

Like Chris Hindle's sig line says "Just put a 57 on it and get off my stage."
Hey, I represent uuum resent that comment. ::)

Sure, there are better, but if you can't use one as a throw-and-go and get decent results, maybe Live Sound isn't your "calling".....
Chris.
Title: Re: Help needed making microphones more sensitive
Post by: brian maddox on July 26, 2019, 02:24:30 pm
Head... in... hands...

I, like most people, had a fairly vaunted idea of what the White House AV must be like given the stature of the office.

And then i worked my first presidential gig.  Educational, to put it mildly...
Title: Re: Help needed making microphones more sensitive
Post by: Tim McCulloch on July 26, 2019, 06:29:37 pm
I, like most people, had a fairly vaunted idea of what the White House AV must be like given the stature of the office.

And then i worked my first presidential gig.  Educational, to put it mildly...
WHCO mission is pretty simple most of the time, at least compared to what the AV contractor has to accomplish while keeping the Secret Service from shooting them.