Digital noise on a sound recorder

timtimtim

Member
I bought a Zoom H1 portable recorder for recording film sound. I was very pleased with it at first, but now I realise that when it is switched to WAV which is what I would always use for film or any other sound because MP3 or any other form of compression is inferior, it has a soft continuous noise at about 1kHz and a clicking sound at 3 Hz. This is present whether using its own mics or with external mic, and increases as the record level is increased.

This is very disappointing. Can anyone give me advice on a portable sound recorder which is free of this problem?
 
I use both the Tascam DR 40 as well as the Zoom H6 for recording Podcasts as well as field interviews. Both of these seem to have the same hum if I use the AC power supply or the USB power supply, but both will have 0 hums if I just run them off of the internal battery power. This happens even when I have them plugged into my LiveWire Power Conditioner. You should be able to remove/reduce the hum using eq at those frequencies as well.

You also have the option of just recording in the mp3 format. I do understand that wav is better, but, if you render your audio at 320kbps, 99.9% of average people listening, will never know the difference. Mixing and mastering engineers might notice, but most others won't. Since you mentioned that this also happens when you use the internal mics, I would rule out the mic & cable as the source.

You should also know that if you are recording close to high voltage overhead power lines, or other high powered electronic devices, this may affect you recording as well. Since wav is a better format, it may be happening with the mp3 as well, just not as pronounced as the wav format.
 
I've had a Zoom H2 almost since they came out and been using my H6 for a couple years at least. The H2 is quiet enough for any kind of live environment IMO, and the H6 effectively silent. I always record 24bit WAV, usually 44.1kHz (or sometimes 48kHz if I know at least some of the recording will likely be used with video - only because I read somewhere to do that!). Then I dither in the DAW for 16bit, and either to 256 or 320 for MP3, and AIFF (Apple non-lossy) if syncing the audio to video (I use iMovie or Final Cut Pro).

There's no noise with the H6 save any self-noise from the mic(s). I highly recommend that recorder to anyone. I run it off of a USB battery pack - keep a couple charged in the bag so I never worry about power or AC hum.
 
Thanks for that info. Someone suggested changing the SD card, I did but it didn't change anything. I'm wary of buying Zoom again, and I don't need an expensive recorder with lots of channels and options. I'm recording film sound with a single mic so I only need mono, even stereo is unnecessary. Does anyone know much about the Tascam DR-05? Has it no digital noise?
 
None of the recorders mentioned should have the problem you have - it sounds like a fault to me! None of my digital recorders going back to the first DAT made any noise I could detect internally.
 
... I'm wary of buying Zoom again, and I don't need an expensive recorder with lots of channels and options. I'm recording film sound with a single mic so I only need mono, even stereo is unnecessary. Does anyone know much about the Tascam DR-05? Has it no digital noise?
A friend has an H1 and it's fine - no noise other than wind noise that I've ever noticed. Another friend has a couple of those Tascam recorders and they work well, but there's no reason they would be any better than an H1 that's working the way it should.

How about putting the Zoom on a desk and talking into it from about 3 feet away, level set about -6dB or so and posting the sound clip. (The sound you describes reminds me of someone who was picking up the sound of their watch when holding a recorder in their hand - honest.)
 
here is the noise using int mics (same with ext mic)

Your input level is way to low. Your file shows a -44.9dbs. It should be between a -12db and -18dbs for the best signal to noise ratio you can have for digital recording. You are also recording in stereo with the right channel only picking up the mic. Try switching your recorder to mono and adjusting your input level, then re-post the audio. As far as the freq go, it is very noisy from around 40hrz to 10,500hrz as per the picture below. This was after I pumped it up to a -13LUFS.

View attachment 100383

This is what the wave form looks like at a -13LUFS @ a -0.1dbTP.

View attachment 100384

This is what the audio sounds like at that level in mono.
 
Last edited:
While it is very low in level, it really shouldn't be there. It's picking up interference from one of the internal data lines, and is not something you can cure yourself. It needs to go back, but I suspect they'll just replace it. It is NOT normal, and while very low level - it shouldn't be there, however, I suspect that if you record something at normal levels, the noise probably won't even be noticed - I had, like the others, to really ramp up the level to reveal it. If it's there on the internal mics, if you record with them peaking say ¾ full scale, by eye, I bet you can't detect it then?
 
I agree that the MP3 is bad. Would like to have the original file as a 24-bit WAV copied off the SD card.

The level is low, but I'm assuming you recorded nothing with the mics on, so the noise level on the left channel is the kind of self-noise I'd expect with the record level actually set pretty high. That's why I'd like to hear it in relation to a spoken voice, The right channel is clearly faulty.

But, if the unit is faulty, send it back to Zoom. If it's been like that for a long time and you're past the warranty date, you'll need to replace it. They don't sound like that normally.
 
OK, this is what Zoom recommends you do with your recorder. You can find the info here.

1. Make sure you are running the latest firmware.

2. Make sure that you have the play back set at the same rate as you have the recording format set to.

3. Set the record mode on "Auto" and do a test. If the meter peaks than back it off a hair or two till it stays within the green/yellow.

If you do all of this and it still does the same as before, you really need to contact Zoom directly and see what your next step should be. Good luck and I hope it is a simple fix!
 
It's true you can't hear it when recording outdoors above ambient level, but it really does show up when recording indoors. Anyway it's crap - it shouldn't do it!
 
It's true you can't hear it when recording outdoors above ambient level, but it really does show up when recording indoors.

Being indoors or out doors has no bearing on your problem when it comes to "ambient levels".

{In atmospheric sounding and noise pollution, ambient noise level (sometimes called background noise level, reference sound level, or room noise level) is the background sound pressure level at a given location, normally specified as a reference level to study a new intrusive sound source}

Anyway it's crap - it shouldn't do it!

EVERY electronic device will create its own noise floor! From micro motors to digital recorders, regardless of how much money you spend. If it has an electric power supply than it has a noise floor. It is mathematically impossible not to do so. If you have tried every suggestion in this thread and you still are not happy with the results, than you will at least have gained a little knowledge for your next purchase.

Honestly, Zoom makes different models of the H1. Which one do you own? You must also be aware that the H1 is absolutely the "Bottom of the Rung" digital recorders. Here is a video that may help you.



Also, are you mounting this on a tripod, or your video recorder? If you are using it via hand held, that will also effect your audio. What mic are you trying to use? Is the mic cable balanced or UN-balanced? Are you going from a 1/4 inch mic cable into a 1/8 inch reducer? Is your mic cable going from mono to a stereo reducer? At this point, I really have run out of ideas to help you out. Like I said, if all else fails, contact Zoom directly. I am quite sure they have spent millions on R&D for this product as well as their other recorders.
 
It's true you can't hear it when recording outdoors above ambient level, but it really does show up when recording indoors. Anyway it's crap - it shouldn't do it!
Did you buy it new? Has it always done this or is it something it started to do later? Stating the obvious, but if it always did it, it should have been returned/exchanged when new.

While it's a $99 recorder, I've got the original Zoom H2 that is over 7 years old now and it still works. But, it's a consumer electronics piece, so pretty much a BIC when it comes to durability. If you bought it at someplace like Sweetwater with a 2-yr warranty, get it fixed/replaced. Otherwise, buy something new there.
 
A post script to this: when I connected the Tascam to the power supply from my mic pre-amp, digital noise re-appeared. After days of experimenting I eventually cured it by adding three series 3.3 ohm resistors in the power line to the Tascam and three .1uF capacitors to ground, so blocking digital noise from getting from the Tascam into the mic pre-amp. What a relief. So the poor old Zoom H1 wasn't to blame. So now I've got two sound recorders.
 
Though the H1 did have digital noise when using it's own mics, so it wasn't so good really, though probably OK on ext mic?
 
A post script to this: when I connected the Tascam to the power supply from my mic pre-amp, digital noise re-appeared. After days of experimenting I eventually cured it by adding three series 3.3 ohm resistors in the power line to the Tascam and three .1uF capacitors to ground, so blocking digital noise from getting from the Tascam into the mic pre-amp. What a relief. So the poor old Zoom H1 wasn't to blame. So now I've got two sound recorders.

Do you have the same problem if you just use the battery power?
 
Back
Top