Topic: Why do my recordings look/sound super distorted?

[Carson]

Hi all,

Recently taped a couple of shows (Turnstile and Perfume Genius) and I've noticed some of them are almost unlistenable, with loud buzzing/distortion.

Currently, I'm using a Rode Smartlav+ (which I know is not a great mic, but the past few recordings I've used it for have turned out somewhat better than my ageing iPhone's internal mic, and haven't been as distorted/buzzy as the last two concerts) with the Voice Recorder Pro app (I experimented with using the Shure MOTIV app but the recording was very muddy - though I was sitting at the back of a venue known for poor acoustics so not if the app was to blame). The Perfume Genius show was recorded in 32-bit as well, although I don't know if it's true 32-bit or just a 32-bit container.

Looking at Audacity, it's almost as if the audio is being squashed down, so there's no peaks above a certain level (this has been the case on all my iPhone recordings). If you look at the screenshot of the Turnstile recording in Audacity, you can easily see the flat vertical bar where it's distorted.

At the moment, I think the main culprit is the mic, but I think the iPhone and/or recording app could be an issue as well. I also keep the mic in my pocket, for stealth and convenience reasons, which could also be muffling the audio. My thesis is mic can't handle the SPL levels of rock concerts, and the lowering the gain on the Voice Recorder Pro app is merely lowering the volume of the output, and not the actual gain (so the levels are still too high and you get extreme distrortion without clipping).

I should add that both were recorded from the center at the barrier - not going to get the best audio from there but I'm much more of a photo/video person so position is non-negotiable for me. But I've used a Zoom h1n and the audio from that sounds so much better it's like night and day. Similarly, pretty much every taper audio I've listened to is lacking the muffling, distortion, and muddiness that characterises my recordings.

I've attached samples of both concerts and screenshots of the audio from Audacity - I plan on replacing my mics at the very least, but would appreciate any other advice on iPhone apps (I believe Apogee is popular here?) and positioning. I'm really focused on stealth, so I'm looking at the SP15C - binaural mics that look a lot like earphones. If anyone else has any recommendations, that would be great - the DPA MMA-A interface paired with a few DPA mics is extremely tempted but very expensive - am I right in thinking this setup wouldn't require an additional battery box?

Apologies for the rambling, but I'll leave you with some ear-shredding audio below.

Perfume Genius Distorted: https://drive.google.com/file/d/1tTGpfCuXicghpqytQ335LxXRt4EipO1b/view?usp=drive_link
Perfume Genius Clean (relatively speaking - this is what the audio sounds like in a "good" section): https://drive.google.com/file/d/1ML25j7t58wQ91-iEnReB1sDPX06dzA99/view?usp=drive_link

Turnstile Distorted: https://drive.google.com/file/d/1d-WqJXQYgNfrPkJDwNss4M-ydsG5aWk6/view?usp=drive_link
Turnstile Clean (at the start of the concert, before the moshing and crowd surfing): https://drive.google.com/file/d/19w-5LOmo2DP2gWOKz1vp_Lwp6JKSkrfP/view?usp=drive_link

[aaronji]

You are overloading the input to the recorder (phone). You need a less sensitive mic or a recorder (phone) that can handle the mic output.

[Carson]

You are overloading the input to the recorder (phone). You need a less sensitive mic or a recorder (phone) that can handle the mic output.

Thanks, that makes a lot of sense. Might look at something like the Deity PR2 and see if the mic still sounds bad - then I’ll know it’s the mics that need replacing. The Deity also does 5V plug-in power, I think, which means it can give enough power to mics to withstand high SPL levels. But I’ll need to do some more googling on which mic/recorder combo to get - but this confirms my suspicion that I’ll need a full kit upgrade.

[morst]

You are overloading the input to the recorder (phone). You need a less sensitive mic or a recorder (phone) that can handle the mic output.

Try recording something that is not as loud, or if you must record the loud thing, try it from much farther away?

[cartmiller]

It definitely sounds like classic SPL overload, and your theory about the Smartlav+ being the main culprit is pretty solid. Those mics just aren’t built to handle the volume and pressure you get at rock shows, especially right up at the barrier, so lowering the app’s gain won’t help if the diaphragm is already distorting before the signal even reaches the phone.

The muffling is also consistent with pocket placement, so between the mic’s limits and the position, you’re fighting an uphill battle.

If stealth is essential, moving to proper high-SPL binaurals like the SP15C is a big step up. They’re designed for concert environments and won’t fold under that kind of volume the way the Smartlav does. And yes, the MMA-A + DPA lavs setup is amazing, but definitely pricey - still, you’re right that you wouldn’t need a battery box with that route.

As for apps, Apogee’s app is usually the most reliable on iOS and tends to give cleaner gain control. But even the best app won’t fix an overloaded mic, so upgrading the mics will be the biggest improvement by far.

Your Zoom H1n comparison tells the story, if that sounds clean from the same spot, your phone setup just isn’t meeting the SPL demand. Once you switch mics, you should notice a massive difference.

[Carson]

Thanks! Will definitely be upgrading my mic(s), and potentially the recorder (currently using my phone) if necessary. Got a few different options to choose from too.

[Pieteker]

Thanks! Will definitely be upgrading my mic(s), and potentially the recorder (currently using my phone) if necessary. Got a few different options to choose from too.

I definitely suggest grabbing a pair of AT853s from the Yard Sale: https://taperssection.com/index.php?topic=208736.0
And together with a Deity PR-2 recorder, it makes for a great combo: https://www.amazon.com/Deity-PR-2-Recording-Filmmakers-Travelling/dp/B0D9KMHC8B/

[daspyknows]

Thanks! Will definitely be upgrading my mic(s), and potentially the recorder (currently using my phone) if necessary. Got a few different options to choose from too.

I definitely suggest grabbing a pair of AT853s from the Yard Sale: https://taperssection.com/index.php?topic=208736.0
And together with a Deity PR-2 recorder, it makes for a great combo: https://www.amazon.com/Deity-PR-2-Recording-Filmmakers-Travelling/dp/B0D9KMHC8B/

I would put more coin in the mics and less in the recorder.  Mics will make a bigger difference once going beyond the phone.