Hi, I'm using the Audio Technica ATR-35S Lavalier Microphone to record persons speaking. I've used this mic many times with Panasonic and Nikon cameras and it's been very good.

This most recent time, it was hooked up to a Samsung A21s cellphone via a USB soundcard plugged into a USB hub, which was then plugged into the cellphone. Meanwhile, the Panasonic HC-V180K was video recording the persons speaking; this was taking place indoors in a closed room.

Several recordings were made and were clean and good. However, in one of the recordings there is a noise that starts off, increases in volume, then dies down. It's not buzzing, or humming, or crackling per se. The closest descriptive word could be crackling, although it's not as sharp as a crackle, and it isn't clothes rubbing on the mike. It steadily increases in volume then dies down after awhile and the noise is at a constant stream while it lasts. It happened twice in the recording, one lasting quite long, the other brief.

This is the first time I've ever had a problem with the microphone. It's also the first time I've used it with a cellphone and I wonder if that's the problem, or if it's the cord itself (about 20 feet long) that's becoming faulty. Having forgotten to put the cell on airplane mode (it was on silent with no vibrate) the phone log has no record of calls coming into the cell at the time the recording was made.

Thanks for any advice, so that the next time I'll know how to avoid it. Might Audacity clean this up?

Inexpensive lav mics are more susceptible RF interference or any type of electrical or radio waves. Better lav mics have shielding in the cable and capsule. Phones don't make great recorders because their not designed to that purpose.

One solution is run a lav directly into an audio recorder like the zoom H1. There are dedicated lav recorders like the Tascam DR-10L. And there are a multitude of wireless recorders.

https://www.bhphotovideo.com/c/search/BI/2855/KBID/3801 (https://www.bhphotovideo.com/c/search/BI/2855/KBID/3801/BI/2855/KBID/3801)

Depends how much you want to spend.

I suspected it was the cellphone, as I've never had a problem with the lav when it connected directly to two camcorders. Was your link intended to go straight to a product? It goes to the B&H homepage. I'll search for the Zoom H1 and DR10-L. Thanks for the response.

An audio sample would make it easier for the rest of us to identify the sound. Thought it might be worth mentioning.

Andrew

I suspected it was the cellphone, as I've never had a problem with the lav when it connected directly to two camcorders. Was your link intended to go straight to a product? It goes to the B&H homepage. I'll search for the Zoom H1 and DR10-L. Thanks for the response.
Since there are so many wireless audio recorders on the market, the link was supposed to show that category type.

But I'd agree the phone most likely was the culprit. Even when you're not making a call the phone can put out strong radio signals next to it.

DJI, Rode, and Hollyland wireless recorders. These also come with adapters to plug into your phone or camera. These type of devices are all the rage because you can clip on to your shirt and get good audio.

I had my eye on the Hollyland Lark because it's so small, convenient and easy to use
https://www.bhphotovideo.com/c/product/1809525-REG/hollyland_hl_lark_m2_combo_lark_m2_2_person_wireless.html/BI/2855/KBID/3801 (https://www.bhphotovideo.com/c/product/1809525-REG/hollyland_hl_lark_m2_combo_lark_m2_2_person_wireless.html/BI/2855/KBID/3801/BI/2855/KBID/3801/BI/2855/KBID/3801)

But if you solved your problem no need to spend the money on a new device if not needed.

An audio sample would make it easier for the rest of us to identify the sound. Thought it might be worth mentioning.

Andrew

That would be ideal; however, not possible in this case. Thanks for the interest in getting to the root of it.

Since there are so many wireless audio recorders on the market, the link was supposed to show that category type.

But I'd agree the phone most likely was the culprit. Even when you're not making a call the phone can put out strong radio signals next to it.

DJI, Rode, and Hollyland wireless recorders. These also come with adapters to plug into your phone or camera. These type of devices are all the rage because you can clip on to your shirt and get good audio.

I had my eye on the Hollyland Lark because it's so small, convenient and easy to use
https://www.bhphotovideo.com/c/product/1809525-REG/hollyland_hl_lark_m2_combo_lark_m2_2_person_wireless.html/BI/2855/KBID/3801 (https://www.bhphotovideo.com/c/product/1809525-REG/hollyland_hl_lark_m2_combo_lark_m2_2_person_wireless.html/BI/2855/KBID/3801/BI/2855/KBID/3801/BI/2855/KBID/3801/BI/2855/KBID/3801)

But if you solved your problem no need to spend the money on a new device if not needed.

Thanks for the direct link, will look into those devices.

You sure it didnt get damp? Lewve it somewhere warm for a few days and test again?

I am not surprised there is noise with 20 foot unbalanced mic cable. A faulty cable can induce noise as well, especially when plug-in power (bias voltage) is present.
After the fact, you could try a vinyl click and crackle removal tool, which may or may not help.

This is the first time I've ever had a problem with the microphone. It's also the first time I've used it with a cellphone and I wonder if that's the problem, or if it's the cord itself (about 20 feet long) that's becoming faulty. Having forgotten to put the cell on airplane mode (it was on silent with no vibrate) the phone log has no record of calls coming into the cell at the time the recording was made.


Without hearing it I can't be sure, but it's probably interference from your cell phone talking to the local tower and transferring technical data. They do this periodically (every few minutes if the phone is stationary, more if it's moving) when you aren't using it for phone calls. Why? Because cell phones are mobile, and in order for a call to complete to your phone, the carrier network has to know where your phone is. They also negotiate signal gain, which might have been why your noise went up and down in level. IDK, it's been a while since I really looked into this.

Had your phone been in "airplane mode" it might well not have dumped "digital hash" on your analog mic cable. Had your mic been connected to your phone using an XLR balanced cable, it might not have been able to corrupt your mic signal. Also, had you been monitoring the signal on headphones you would likely have caught the problem before you made the recording, giving you time to correct the problem one way or another.

If you insist on recording audio from an external mic using a smartphone (I recommend against, but you know what you need to do better than anyone else), you might want to buy something like a Saramonic SmartRig, or an iRig Pre 2. I've never used either one. I've only read enough to know they exist, so I can't vouch for either, or for any of the others like them on the market.

If you can, consider instead an audio recorder designed for the task. Something like a Tascam DR60D MK 2 will give you much better sound, and it has the fittings to be used between a tripod head and a camera. Since you are using a lav mic, maybe something like a Tascam DR-10L recorder that records from a lav mic and you can just drop the recorder in a pocket. But you won't be able to monitor it, so...

I hope this helps. Without hearing the audio I'm really just guessing, so clearly YMMV.

You sure it didnt get damp? Lewve it somewhere warm for a few days and test again?

It wasn't damp, no.

I am not surprised there is noise with 20 foot unbalanced mic cable. A faulty cable can induce noise as well, especially when plug-in power (bias voltage) is present.
After the fact, you could try a vinyl click and crackle removal tool, which may or may not help.

Using Audacity, I selected the Click Removal and Noise Reduction tool, but couldn't get it to work.

Without hearing it I can't be sure, but it's probably interference from your cell phone talking to the local tower and transferring technical data. They do this periodically (every few minutes if the phone is stationary, more if it's moving) when you aren't using it for phone calls. Why? Because cell phones are mobile, and in order for a call to complete to your phone, the carrier network has to know where your phone is. They also negotiate signal gain, which might have been why your noise went up and down in level. IDK, it's been a while since I really looked into this.

Had your phone been in "airplane mode" it might well not have dumped "digital hash" on your analog mic cable. Had your mic been connected to your phone using an XLR balanced cable, it might not have been able to corrupt your mic signal. Also, had you been monitoring the signal on headphones you would likely have caught the problem before you made the recording, giving you time to correct the problem one way or another.

If you insist on recording audio from an external mic using a smartphone (I recommend against, but you know what you need to do better than anyone else), you might want to buy something like a Saramonic SmartRig, or an iRig Pre 2. I've never used either one. I've only read enough to know they exist, so I can't vouch for either, or for any of the others like them on the market.

If you can, consider instead an audio recorder designed for the task. Something like a Tascam DR60D MK 2 will give you much better sound, and it has the fittings to be used between a tripod head and a camera. Since you are using a lav mic, maybe something like a Tascam DR-10L recorder that records from a lav mic and you can just drop the recorder in a pocket. But you won't be able to monitor it, so...

I hope this helps. Without hearing the audio I'm really just guessing, so clearly YMMV.

Yes, I'm sure Airplane Mode would have eliminated that. It was the first time I was utilizing that method of recording. The phone's headset itself records very, very clean audio, but I had to have the phone within my reach, not in the speaker's reach and the headset cord is short so that made the lavalier necessary. Still, the clean part of the audio from the lavalier is quite good, although it's not the best method out there.

Thanks again for all the responses.

Using Audacity, I selected the Click Removal and Noise Reduction tool, but couldn't get it to work.

I a not very familiar with Audacity. usually use the restoration tools included with Sound Forge Pro which are decent. If they cannot fix a problem, I resort to Steinberg's SpectraLayes Pro. iZotope's RX is very good to,especially RX Advanced, but it is costly.

Helen,

I certainly concur with others' suggestions that the phone should be in airplane mode.

I also suggest getting all the USB junk out of the circuit if possible.

If your phone has a 3.5mm headset jack, you should be able to get a Y/breakout cable that plugs into the phone, then provides two separate 3.5mm jacks: one for a mono mic (like the one you're using now), and the other for a stereo headset (so you can monitor while recording).

This breakout cable should work with your phone. It will let you eliminate the external USB conversions, which are a potential source of grounding and noise issues.

https://www.amazon.com/Hosa-YMM-108-3-5mm-Breakout-Cable/dp/B09BK7WMC6/din02c-20

There are various kinds of breakouts, so be sure you get the right type. Of course you'll need one with a TRRS plug, like this one. This is technically called a CTIA breakout cable. (There's another type called OMTP which will NOT work for you.) The two jacks are usually pink/red (for a mono mic) and green (for stereo earphones). There may be some oddball manufacturers who use different color coding.