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Title: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 12:15:36 am
At the show right now - singer mentioned last gig the band played (they used in house system)... She had to switch out her Senny wireless mic to a wired mic- reason was loud popping through the PA. We have never had this problem in the past so I figured it was a one off or something the sound guy did. We started out fine and then right toward the end of the first set- there it was and it was LOUD!
It happened when she moved the mic- when on the stand, it was fine. We switched it out anyway for a shure beta and so far no issues.... Why all of a sudden? Same mic used for past 2 years with no issues...
Title: Re: Wireless mic pops
Post by: g'bye, Dick Rees on August 29, 2015, 07:51:00 am
Sounds like something loose inside or a failing connection.

I have a mic that uses a 9v and requires the battery to be shimmed up tight to prevent pops.
Title: Re: Wireless mic pops
Post by: Kevin Maxwell on August 29, 2015, 09:37:54 am
At the show right now - singer mentioned last gig the band played (they used in house system)... She had to switch out her Senny wireless mic to a wired mic- reason was loud popping through the PA. We have never had this problem in the past so I figured it was a one off or something the sound guy did. We started out fine and then right toward the end of the first set- there it was and it was LOUD!
It happened when she moved the mic- when on the stand, it was fine. We switched it out anyway for a shure beta and so far no issues.... Why all of a sudden? Same mic used for past 2 years with no issues...

What Dick says and below is a cut and paste of what I have said in the past if you are using 9v batteries. If you are using AA batteries check to make sure you don’t have any residue on the battery terminal in the mic caused by a leaking battery. That can be really hard to clean up to impossible to clean.

If the Sennheiser mic is the first generation series they take a 9v battery. Have you ever stood a bunch of 9v batteries next to each other and observed the differences in the height of them? If you use a taller model battery regularly and then switch to a shorter one you may find that the contacts in the transmitter have been bent enough that a shorter battery may not make good contact. I have experienced this problem many times over the years. I have had to put a shim under the battery to make a good contact more times then I can remember. 
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 11:10:21 am
Thanks guys for those suggestions. Her mic is only 2 years old and uses AA's. She gave it to me last night to bring home to troubleshoot but I don't think I want to if its going to cause nasty pops- apart from that I don't really know what to do other than check what is suggested here. Gonna take a look after I've finished my coffee....(very late night)....
Title: Re: Wireless mic pops
Post by: g'bye, Dick Rees on August 29, 2015, 11:36:43 am
Thanks guys for those suggestions. Her mic is only 2 years old and uses AA's. She gave it to me last night to bring home to troubleshoot but I don't think I want to if its going to cause nasty pops- apart from that I don't really know what to do other than check what is suggested here. Gonna take a look after I've finished my coffee....(very late night)....

Get her to 'fess up on the last time she dropped it on the floor...

It should be easy enough to unscrew the grill and examine the element.  Any poor wiring or connection should show up with a poke or a wiggle here and there.  If that doesn't reveal the cause, tell her it's broken and have her buy a new one.


tuff luv.
Title: Re: Wireless mic pops
Post by: Jim Rutherford on August 29, 2015, 01:20:23 pm
Debbie,
If your worried about the pops, then trouble shoot it without the speakers powered.  Just watch the channel strip as you shake the mic, etc to reproduce it.
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 01:23:46 pm
A mic drop is a possibility Dick and I will ask her this evening- running sound for the same band tonight.
I just took a look at it and I can't seem to find a way in. The transmitter section only opens up the battery compartment but will not open any further and the capsule section is sealed. Looks like it is a throw away design which leaves me back where I started.
I checked the batteries and they are nice and tight, clean with no signs of corrosion or contamination.
I cleaned the contacts in the head also.
Tonight I'll do an RF scan and set a different (probably) frequency. Other than that - unsure what to do. I really don't want to have any nasty pops through my speakers again so how do I test it without taking the risk?.......oh the trials of being a good little sound person and a personal friend to the band.
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 01:25:57 pm
Debbie,
If your worried about the pops, then trouble shoot it without the speakers powered.  Just watch the channel strip as you shake the mic, etc to reproduce it.

Just read this. Jim... Good idea, I'll try to cause a pop with the speakers off. What about simply muting the channel and watching the strip?
Title: Re: Wireless mic pops
Post by: g'bye, Dick Rees on August 29, 2015, 01:26:40 pm
Which model # is it?  Sounds like the cheapest.

If it's good on the stand but not in the hand it's mechanical/electrical, not RF.

What happens if you shake her?
Title: Re: Wireless mic pops
Post by: John L Nobile on August 29, 2015, 01:33:06 pm
I used to have that problem years ago when I was using an AKG system. One lead to the mic element would break off but still made contact until it bounced around. Very annoying and all 4 mics had the same issue. A real pain to solder as well.
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 01:54:30 pm
Which model # is it?  Sounds like the cheapest.

If it's good on the stand but not in the hand it's mechanical/electrical, not RF.

What happens if you shake her?

Nailed it- it is the cheapest... The EW100..
I am quite impressed with the build quality though I must admit. This is the first time I've taken a close look at one and the mic quality seems real nice. The receiver of course is very similar to the EW300 transmitters I have for my iems. I was able to get around the menu on it easily - not that much to see really.
So yes I noticed the first pop when she had it in her hand and off the stand but the second pop happened with it on the stand but she was pulling it over to one side whilst still on the stand. When it was left alone it was fine. So it wasn't being shaken up at all.
Also I doubt it has been dropped because she babies this thing and it doesn't have a mark on it- it looks brand new!
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 01:55:31 pm
I used to have that problem years ago when I was using an AKG system. One lead to the mic element would break off but still made contact until it bounced around. Very annoying and all 4 mics had the same issue. A real pain to solder as well.
I wish I could get in there to see..
Title: Re: Wireless mic pops
Post by: Jim Rutherford on August 29, 2015, 01:59:24 pm
Yes, mute the channel, then shake and stir.
Title: Re: Wireless mic pops
Post by: g'bye, Dick Rees on August 29, 2015, 02:08:36 pm
Reading up on the mic, it would seem like you can change capsules even on their cheapest hand-held TX...which would suggest that something can simply come loose.
Title: Re: Wireless mic pops
Post by: Lee Buckalew on August 29, 2015, 02:18:32 pm
Reading up on the mic, it would seem like you can change capsules even on their cheapest hand-held TX...which would suggest that something can simply come loose.

This is correct, all Evolution G3 series have interchangeable capsules.

Lee
Title: Re: Wireless mic pops
Post by: Lee Buckalew on August 29, 2015, 02:19:15 pm
Nailed it- it is the cheapest... The EW100..
I am quite impressed with the build quality though I must admit. This is the first time I've taken a close look at one and the mic quality seems real nice. The receiver of course is very similar to the EW300 transmitters I have for my iems. I was able to get around the menu on it easily - not that much to see really.
So yes I noticed the first pop when she had it in her hand and off the stand but the second pop happened with it on the stand but she was pulling it over to one side whilst still on the stand. When it was left alone it was fine. So it wasn't being shaken up at all.
Also I doubt it has been dropped because she babies this thing and it doesn't have a mark on it- it looks brand new!

Debbie,
Watch the metering while testing and confirm that the noise is coming from the receiver (watch the AF signal at the receiver) audio input section.
If you see an AF hit and hear the noise it could be the handheld which you can try to replicate or it could be an outside interference causing an RF hit which should show both an AF and RF meter spike.
If you hear the noise but don't see an AF spike on the receiver then the noise is getting in somewhere after the mic receiver.
Any other 100 series handhelds around?  You could swap capsules or even, if in the same freq range, swap HH MICDS and see if the noise follows the HH or not.

Lee
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 02:34:27 pm
Debbie,
Watch the metering while testing and confirm that the noise is coming from the receiver (watch the AF signal at the receiver) audio input section.
If you see an AF hit and hear the noise it could be the handheld which you can try to replicate or it could be an outside interference causing an RF hit which should show both an AF and RF meter spike.
If you hear the noise but don't see an AF spike on the receiver then the noise is getting in somewhere after the mic receiver.
Any other 100 series handhelds around?  You could swap capsules or even, if in the same freq range, swap HH MICDS and see if the noise follows the HH or not.

Lee

Don't have or know of anyone with the same model.
I am going to take my wireless mic this evening for her because I know I can trust it, I have the Audix OM5 RAD360 system and I like it a lot. That way if we don't get time to troubleshoot I can go straight for the Audix.

In fact - I'll check on mute right now…..
Title: Re: Wireless mic pops
Post by: Tim McCulloch on August 29, 2015, 02:56:59 pm
Hi Debbie-

If this "pop" is loud enough to make you worry about your speakers I think the problem could be somewhere else completely.... like in something using phantom power.  A non-phantom powered mic with intermittent connections of audio wiring generally doesn't make enough noise that I get concerned about the PA.
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 29, 2015, 04:01:53 pm
Hi Debbie-

If this "pop" is loud enough to make you worry about your speakers I think the problem could be somewhere else completely.... like in something using phantom power.  A non-phantom powered mic with intermittent connections of audio wiring generally doesn't make enough noise that I get concerned about the PA.

Normally Tim Id say this was entirely possible as I was using a condenser for O/H on the drums but everything points to the Senny mic.
1) At the venue last week with the in house system, after the sound guy swapped out the mic for a wired one, the popping disappeared.
2) It only happened last night when the mic was moved and
3) When we switched out the mic for a wired one, the popping went away.

I just did some checking - on mute - whilst making some crazy movements with the mic,  I could not replicate the pops. However, I probably should have tried this little test BEFORE I cleaned all the contacts and tightened everything. So I may have cured the problem for now.
Title: Re: Wireless mic pops
Post by: Kevin Maxwell on August 29, 2015, 11:30:29 pm
Normally Tim Id say this was entirely possible as I was using a condenser for O/H on the drums but everything points to the Senny mic.
1) At the venue last week with the in house system, after the sound guy swapped out the mic for a wired one, the popping disappeared.
2) It only happened last night when the mic was moved and
3) When we switched out the mic for a wired one, the popping went away.

I just did some checking - on mute - whilst making some crazy movements with the mic,  I could not replicate the pops. However, I probably should have tried this little test BEFORE I cleaned all the contacts and tightened everything. So I may have cured the problem for now.

I am pretty sure that the EW100 is available with different mic elements on it. I think they usually come with the 835 head. And according to the 835 manual the windscreen or as they call it “the sound inlet basket” can be unscrewed.

I had an EW300 with the 865 head on it in my hands the other night and it was used by a woman that usually has a lot of lipstick on and there was a lot of it on the windscreen. I said that can clog up the windscreen and affect the sound. So I showed them how to unscrew the windscreen so they could clean it. When you unscrew the windscreen you can see the mic diaphragm in there. The 865 looks like it is suspended in there and if it is anything like some Shure mics that I have worked on the wires to the capsule can break or just come a little loose   

So I am not sure what mic head this wireless transmitter has on it but the windscreen should unscrew and you should be able to see inside there. And look for how it is wired and if anything is loose.

But as you said maybe cleaning what you did fixed it. But some vigorous shaking should make it fail if you didn’t fix it. Assuming it is a physical mic problem and not an intermittent RF problem. 
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 30, 2015, 10:37:51 pm
I am pretty sure that the EW100 is available with different mic elements on it. I think they usually come with the 835 head. And according to the 835 manual the windscreen or as they call it “the sound inlet basket” can be unscrewed.

I had an EW300 with the 865 head on it in my hands the other night and it was used by a woman that usually has a lot of lipstick on and there was a lot of it on the windscreen. I said that can clog up the windscreen and affect the sound. So I showed them how to unscrew the windscreen so they could clean it. When you unscrew the windscreen you can see the mic diaphragm in there. The 865 looks like it is suspended in there and if it is anything like some Shure mics that I have worked on the wires to the capsule can break or just come a little loose   

So I am not sure what mic head this wireless transmitter has on it but the windscreen should unscrew and you should be able to see inside there. And look for how it is wired and if anything is loose.

But as you said maybe cleaning what you did fixed it. But some vigorous shaking should make it fail if you didn’t fix it. Assuming it is a physical mic problem and not an intermittent RF problem.

Thanks Kevin..its an 835. If there is a way into it, I couldn't find it.
I gave it back to her last night but she never got to use it. We'll try again at the weekend and hopefully it will be fine. If not I'll dive in a little deeper I suppose….
Title: Re: Wireless mic pops
Post by: Lee Buckalew on August 31, 2015, 06:18:57 am
Thanks Kevin..its an 835. If there is a way into it, I couldn't find it.
I gave it back to her last night but she never got to use it. We'll try again at the weekend and hopefully it will be fine. If not I'll dive in a little deeper I suppose….

Debbie,
The windscreen on the G3 Evolutions is usually very difficult to get off.  I can't remember if it unscrews at the label band around the middle of the basket or if it unscrews just above the threaded section that holds the complete mic capsule to the mic body.  I seem to recall that it is at the label but it's been quite some time since I've needed to take the windscreen off.

Here is a link to a picture of the mic capsule when it is removed from the mic body.
http://en-us.sennheiser.com/images/560/all/square/6247/square_louped_mmd-835_sq-01-sennheiser.jpg

Lee
Title: Re: Wireless mic pops
Post by: Kevin Maxwell on August 31, 2015, 09:05:20 am
The 865 comes apart in the middle at the label band around the middle of the basket. I don’t know about all of the other models.

I am pretty sure that the windscreen (grill) on the 835 unscrews just above the threaded section that holds the complete mic capsule to the mic body. And this makes it hard or tricky to get it to unscrew. When you try to unscrew it the whole head usually comes off of the transmitter. The trick is usually to tighten the capsule down a little bit more then is really needed to hold it in place and then give it a quick twist to take the windscreen off. It can take a bunch of tries before you have the right combination to get it off of the capsule. 

See the picture that shows the grill after its removed from the bottom in the attached link.
http://www.performanceaudio.com/item/sennheiser-073526-replacement-grill-for-e835/49833/

With the capsule off of the transmitter do you see a slot in the treaded part on both sides of it? If you do you may be able to use something to hold the capsule in place to remove the grill. But be very careful or you will mess up the threads. I can’t find an image on line of the capsule from the bottom.
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on August 31, 2015, 10:42:35 pm
Then I must have missed something because I was able to unscrew the grill piece from the mic capsule and I could unscrew the capsule piece from the body but the capsule piece and the body were sealed. They connected via a flat metal plate in the capsule and small contacts in the body. Nothing was open to wiring at all….
Title: Re: Wireless mic pops
Post by: Kevin Maxwell on August 31, 2015, 10:51:55 pm
Then I must have missed something because I was able to unscrew the grill piece from the mic capsule and I could unscrew the capsule piece from the body but the capsule piece and the body were sealed. They connected via a flat metal plate in the capsule and small contacts in the body. Nothing was open to wiring at all….

Then you have probably gone as far as you can go with anything you could have serviced. The more expensive mics (at least the 865 does) have a different construction to them. And I didn’t know what capsule you had at first.

Hopefully what you have done already has fixed the problem. Intermittent problems are the hardest thing to trouble shoot. 
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on October 24, 2015, 05:40:23 pm
Update on this...
The singer had used my mic for a few shows and the last show the band had, they used someone else for sound and she used her Senny again apparently without any issues. The sound guy they used did a freq scan and decided that was the issue with it and told her he had fixed it.... Yeah right- so last nights gig we did the sound check and I started to play some background music till the band went on.
I hadn't muted the mics like I normally do and suddenly there was a static distortion from hell that came though the speakers. OMG.... Everyone screamed and I thought I'd lost my horns in my DSR's and my monitors. As soon as the noise started it stopped and I muted everything. Good job I did, I watched the meters and every 10 seconds or so the wireless mic meter went crazy into the red for about 3 seconds and then went back down. This happened till we disconnected her receiver.
No surprises we put her straight on a wired mic and I refuse to let her use the Senny ever again till repaired or replaced. Good news is my speakers made it!
The first time we had problems, it was a loud pop but this was much nastier.....
Title: Re: Wireless mic pops
Post by: Mac Kerr on October 24, 2015, 05:46:20 pm
Update on this...
The singer had used my mic for a few shows and the last show the band had, they used someone else for sound and she used her Senny again apparently without any issues. The sound guy they used did a freq scan and decided that was the issue with it and told her he had fixed it.... Yeah right- so last nights gig we did the sound check and I started to play some background music till the band went on.
I hadn't muted the mics like I normally do and suddenly there was a static distortion from hell that came though the speakers. OMG.... Everyone screamed and I thought I'd lost my horns in my DSR's and my monitors. As soon as the noise started it stopped and I muted everything. Good job I did, I watched the meters and every 10 seconds or so the wireless mic meter went crazy into the red for about 3 seconds and then went back down. This happened till we disconnected her receiver.
No surprises we put her straight on a wired mic and I refuse to let her use the Senny ever again till repaired or replaced. Good news is my speakers made it!
The first time we had problems, it was a loud pop but this was much nastier.....

Had she turned the mic off? This is fairly normal behavior if the transmitter is turned off. Are there other RF mics in use, and where were they when this happened? If other mics got piled all together they will create huge IM products that can completely wipe out everything around them. Doing a frequency scan without also doing the IM calculations only works if you only have 1 or 2 RF mics. Once you have 3 or more RF mics or IEMs or RF comms you need to also do the IM calc to minimize the chance of interference of this type.

Mac
Title: Re: Wireless mic pops
Post by: Debbie Dunkley on October 24, 2015, 11:45:33 pm
Had she turned the mic off? This is fairly normal behavior if the transmitter is turned off. Are there other RF mics in use, and where were they when this happened? If other mics got piled all together they will create huge IM products that can completely wipe out everything around them. Doing a frequency scan without also doing the IM calculations only works if you only have 1 or 2 RF mics. Once you have 3 or more RF mics or IEMs or RF comms you need to also do the IM calc to minimize the chance of interference of this type.

Mac


The mic was off. No other wireless mics were being used but we did have 2 iem transmitters on also. Weird thing is we have done this venue many many times in the past with more iems in use and never a hint of problems. This was before the episode where the popping occurred though.
Title: Re: Wireless mic pops
Post by: Andrew Henderson on October 24, 2015, 11:49:00 pm
Debbie, is this an older, 600-700MHz unit? I had this happen with a Senny wireless handheld recently; I'll have to check the model number next time I'm doing work at that particular church. There was a terrible intermittent noise, when the mic transmitter was on or off! I finally realized that it happened every time a nearby TV was turned on. I checked the frequency later, and sure enough, it was one of the older models within the digital TV band. Needless to say, I put it out of commission.
Title: Re: Wireless mic pops
Post by: Mac Kerr on October 24, 2015, 11:50:42 pm

The mic was off. No other wireless mics were being used but we did have 2 iem transmitters on also. Weird thing is we have done this venue many many times in the past with more iems in use and never a hint of problems. This was before the episode where the popping occurred though.

You should not turn off any RF mics when you have faders open. This is just asking for interference through your system. When they are off they are open to pick up even weak interference. Keep the transmitters powered on.

Mac
Title: Re: Wireless mic pops
Post by: Mac Kerr on October 24, 2015, 11:55:51 pm
Debbie, is this an older, 600-700MHz unit? I had this happen with a Senny wireless handheld recently; I'll have to check the model number next time I'm doing work at that particular church. There was a terrible intermittent noise, when the mic transmitter was on or off! I finally realized that it happened every time a nearby TV was turned on. I checked the frequency later, and sure enough, it was one of the older models within the digital TV band. Needless to say, I put it out of commission.

Wireless Workbench is free software, and it will not only tell you what digital TV stations could cause interference at your location, it will pick frequencies for your mics, IEM systems, and RF comm that will avoid those TV channels, and not cause strong intermod products between your systems. It is important that you run this software for the location of every venue you will be at, and update the TV channel database occasionally to keep it current.

Not using this, or similar software is equivalent to burying your head in the sand and hoping no one notices you.

Mac