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AlienXXX wrote:
I have one as well, and I am quite pleased with it. Although my recording requirements are perhaps fairly modest. And most of the time I do not record outside (need to bui the foam wind protector)

My experience with electromagnetic interfeerence is mostly from deliberate recordings I have made using a few coil sensors (some home made).
Initially I plugged these directly onto my soundcard or laptop mic socket.
Now I have used them with the Zoom H1 too, and even made some outdoors recordings with them... Had a particluarly interesting recording made when aboard an electric train... If I can find it I will post on Freesound.

I was very pleased with that recorder too.

Did you ever experience electronic interference problemns with it ?

AlienXXX wrote:
Did you ever experience electronic interference problemns with it ?

EDIT: later i used a 5v battery in the USB as a powersupley

Actually, I have tried placing the coil sensor next to the H1 recorder itself.
I could pickup different electromagnetic noise from different parts and also different patterns from different actions (different noises when not recording, starting a recording, during recording and stopping recording).

But such coil sensors very are sensitive to EMI. Much more than what the H1 recorder should be by itselt.
Need to make some experiments with the H1, such as placing it next to my internet router to see if it picks up any interference....

I had a walkman once that would pickup interference from the Heathrow airport radar if I was close enough... close enough probably meant anything less than half a mile away!

bulbastre wrote:
... I don't understand a single word you're saying.

What I understand is that:
1. It might come from some fluorescent light provided they somehow might be affected by thunderstorms. I don't know what's EMI. I also don't see a direct relation between working at a different voltage and emiting a high frequency sound.

The mains electricity voltage can become unreliable during electrical storms as a result of lightning hitting powerlines. If an electrical device is not supplied with the correct voltage it does not operate correctly,e.g. a spluttering fluorescent light. The electrical noise "sound" can be picked up by induction, like a radio , not sound traveling through air.

The unprocessed sound reminded me of those “subliminal” message things, (here's one I made earlier ...http://www.freesound.org/people/Timbre/sounds/133026/ ). So I demodulated it with an arbitrary 11.8KHz sine carrier. {Some fluorescent lamps have a frequency of ~10KHz ... see wikipedia.org Fluorescent_lamp#Electronic_ballasts )

I am watching this thread with interest.

Sorry for the delay.

Two days ago I recorded 4 hours of WAV audio at 24bits-96Khz WITHOUT a thunderstorm. The sound is there 3 or 4 times.
I'm trying to upload the segment where it becomes more prominent. I'm uploading it to MegaUpload, since I'm premium. It'd take me AGES to upload it here.
I recorded at 96Khz because a friend of mine told me the sound could be coming from a subharmonic of fluorescent light, since they work above 20Khz, unless it's from before the 90's (looked it up at wikipedia).

BEFORE you see the uploaded sound I have two controversial matters.
1. There was no thunderstorm. It's been a shitty weather in Spain lately, but the recorded section did not feature a proper thunderstorm, so the magnetic-electrical forces of the thunderstorm playing a role in this mistery can be mostly discarded.
2. There is no harmonics above 20Khz. There's nothing there you couldn't see before, but I'm uploading it anyways.

What I'm going to do now is:
Record 4 hours WAV 24bits-96Khz WITHOUT thunderstorm with my device COVERED IN ALUMINIUM.
a. If the sound disappears - magnetoelectrical interference.
b. If it doesn't - I'm calling Fringe division.

PS: Of course, AlienXXX, you can do whatever you please with your spare time. You don't need to ask permission to help me (us) out with this. If your coils can provide any valuable information, please don't hesitate to use them

bulbastre wrote:
PS: Of course, AlienXXX, you can do whatever you please with your spare time. You don't need to ask permission to help me (us) out with this. If your coils can provide any valuable information, please don't hesitate to use them

LOL
I was not "asking for permission". Just meant that I have some coils that pickup electronic interference and the same model of recorder, so if there was something in particular that you thought might be causing the interference I could see if I could pickup something with the coils... although it is a long-shot.

What I will do when I have a bit of time, anyway, will be to see what I can record with the coil at maximum sample-rate next to a fluorescent light - then I can look in the recording for high freq sounds.
I will also try to see what I can pickup with the coils from the recorder itself.
I will post the sounds here...

Ok, I don't have a lot of free time, either, and uploading big files is a pain in the ass, but eventually I will post the new recordings.

bulbastre wrote:
Ok, I don't have a lot of free time, either, and uploading big files is a pain in the ass, but eventually I will post the new recordings.

How big are these files? I mean, I know you recorded a few hours, but can't you trim the parts of interest and upload those only. How big would that be?

I have been uploading some large files, at least large for my usual file size (these are 25-75Mb).
I agree it takes a longtime. Generally I left them to upload while I go to have dinner...

20 minutes at 96Khz-32bits is A LOT of MB.
The real problem is that uploads often fail, forcing me to start the upload again from the beginning.

It takes a lot of tries, even if I partitioned the file in 195MB subfiles.

Hmmm that is bad!
If you haven't done that, can I ask you to post this in the "Bug Reports, Errors and Feature Requests" forum? Maybe one of the techy guys could have a look at it.

Does it happen with all files or mostly when you try to upload large files?
My uploads take a lot of time... 75Mb took longer than 1h. But they are sucessfull.
I think I only had 2 or 3 failed uploads since Freesound 2.0 came online. And one of them was because I accidentally logged out of freesound

Do you have flashplayer 10 ?
Post those details on the "Bug Reports, Errors and Feature Requests" forum and see what the tech guys say. I can't help there as I am not involved.

It must be something involving my internet connection or the fact that I have the files in a external HDD.
This error occurs whether I try to upload them to freesound 2.0 or MegaUpload.

Maybe your connection breaks now and then... And that is really bad when you are trying to transfer large files. Yiu could try to connect to the router using a cable instead of wireless when uploading large files. That might help.

Too complicated. It's simpler just to try and try XD

Ok, I STILL haven't uploaded the files BUT
I recorded 4 hours maximum quality WAV with my ZOOM enveloped in aluminium foil - the sound's still there, as clear and loud as always.

THEREFORE
It's not electromagnetic or radiofrequency interference.

THEREFORE
EITHER it's selfnoise
EITHER it's an exterior "normal" sound

Hmmm... sounds to me like it is the recorder itself, which is somewhat bad news.
I would still advise you to try recording with a different memmory card, as these can have faults that result in noise in recordings, according to Zoom.

So see if you can borrow a different card and try it out.

I already tried with differents SD cards.

Ok, here's the NEWS:

-My EDIROL R-44 is back!
-I recorded and hour and a half with it at 192Khz. No mysterious sound at all.

I consider an hour and a half nonconclusive. I have to record longer and side-to-side with my ZOOM H1.

By the way, it'd be interesting to listen to sound intercepted by the coil. I want to know what that sounds like.

Hello bulbastre

Sorry to hear that it is definetely a problem with the Zoom H1 recorder.
Is it still in the warranty? Maybe you can get it replaced or fixed?

The sounds you get from the coil will depend what electric/electronic equipment you are recording.
Normally you get humm or buzz from the 50Hz mains around most large appliances (TVs and so on) and any transformer or wall-wart. Different transformers can sound very different.
Electronic stuff such as laptops, mobile phones, etc will produce various types of pulses or beeping/buzzing high pitched sounds.
Stuff with motors (CD drives, Hard-drives, hairdriers, etc) will usually produce a whirr or motor drone kind of sound.

Some examples I have recorded:
http://www.freesound.org/people/AlienXXX/packs/5822/

bulbastre wrote:
I already tried with differents SD cards.

Ok, here's the NEWS:

-My EDIROL R-44 is back!
-I recorded and hour and a half with it at 192Khz. No mysterious sound at all.

I consider an hour and a half nonconclusive. I have to record longer and side-to-side with my ZOOM H1.

TADAA!!

I'm back, and I've recorded with BOTH H-1 and R-44 at the same time. At the last 13 minutes of the recording this sound appears:

http://www.freesound.org/people/bulbastre/sounds/137765/

Both of the recorders picked up the same sound. This is the H1 version, tho.
Ok, so we now IT HAS NOTHING TO DO with the recorder. Therefore the sound is "out there".

This last sound is different from the others. It sounds more like a chirp. Crickets chirping in the beginning and birds chirping later. Someone said "bats" earlier? It would explain THIS sound, but I guess it wouldn't explain the PREVIOUS ones.