Ticking Sound in Voice Recording

[neumannu47]

It is pretty well established that some or all of the 8GB Fuze players have a low level clicking noise superimposed over the audio when the Fuze is used in the Voice Recording mode. My unit is exhibiting the problem. Unfortunately, I did not discover the problem until after I recorded my sickly,85 year old father-in-law over Easter.

Several people have suggested that the sound is external (it's not), that a firmware upgrade will fix it (it will not), that reformating the memory will get rid of the clicking (it will not), that the backlight is causing the problem (it's not), that the noise is audio clipping/digital full scale (it's not), that you can filter it out (you can't without a very sophisticaed DSP plug-in, which I don't have), and that exchanging it for a new unit will solve the problem (it will not). I've been an audio recording engineer for 30+ years. The problem that those of with the problem are hearing is a noise that is being generated internally in the Fuze. My guess is that the problem is inherent in the unit and that nothing can be done about it.

To test whether your Fuze has the problem, take your unit into a very quiet room. Place it on record for a minute. Make sure there are no external noises. Stop recording after a minute. Transfer the wave file to your PC. Open the wave file in an audio editing program, such as Adobe Audition, Sony Vegas, or Audacity. Normalize the audio file (such that the maximum peak level of any part of the file is at 99% or so. Do not clip the wave form.) Listen to the file. If you do not hear a ticking sound every 83ms or so, you do not have the problem.

If you go through this test and do not find a problem with your unit, I would very much appreciate you uploading the wave file and posting a link in this thread so that I can hear it. I will try to do the same if anyone wants to hear the ticking sound.

It is really unfortunate that these units have this problem. The recording quality of the Fuze is 22kHz 16 bit, which is excellent for voice-only recordings. The internal microphone is not bad, either. The clicking sound, however, makes the Voice Recorder feature useless. (The FM recording function does not have the problem, which indicates that the ticking sound is probably being picked up by the preamplifier for the internal microphone.)

If you have actually solved this problem or if you have heard of a solution, please post it. At this point, my assumption is that the problem is a design flaw in the Fuze. What would be helpful to know is whether some or all of these units have the flaw.

Here is a file recorded on the Fuze. The only noise in the room is the air conditioner. The ticking sound is very clear.

[phattyguy]

I'm not sure if this is relevent, but my radio recordings skips at what seems to be fixed intervals. I'll have to check on that.

When I say skip I mean, a segment of the recording repeats itself and then continues.

[funman]

I tried this on my Fuzev1 4GB and I can not hear any tick, though there might be a lot of ambiant noise.

Some remarks: the Fuze firmware records mono 24kHz 32 bits, not 22.05kHz 16 bits (at least that's what audacity tells me) and the ticks aren't espaced every 83ms but more like 300 or 400ms (though the first one is around 83ms in your file).

If you have a Fuzev1 do you have rockbox on it ?

You can tune record settings: different sampling and stereo (although stereo is pretty useless with only one microphone), and I'm also curious because I can hear some noise when playing back audio files on my Clipv2 : this noise occur at the same time the CPU is changing its frequency.

EDIT: Which software did you use to normalize ? Audacity seems to "flatten" waves (not sure of the correct term, but a lot of samples are at the same level unlike in your file)

[JK98]

Why are you expecting decent voice recordings from the Fuze? it was not designed primarily to be a recorder. They just threw in a cheap mic and some cheap circuitry to support the voice recording. It does work much better when the player is within 2 or 3 feet of the speaker's mouth. Some people clip a Clip or Clip+ to the speaker's lapel or shirt pocket, and then the recordings aren't that bad.

for voice recording, I suggest that you get something that is primarily a recorder. Olympus makes some inexpensive ones that are usable enough for casual use which record in wma.

[neumannu47]

Originally Posted by funman

I tried this on my Fuzev1 4GB and I can not hear any tick, though there might be a lot of ambiant noise.

Ambient noise will definitely mask the ticking sound.

Some remarks: the Fuze firmware records mono 24kHz 32 bits, not 22.05kHz 16 bits (at least that's what audacity tells me) and the ticks aren't espaced every 83ms but more like 300 or 400ms (though the first one is around 83ms in your file).

You are correct. It is 24K. However, if you look at the properties of the file in Windows Explorer, the bit depth is reported as 16 bits, which is probably correct. It would make no sense whatsoever to record at 32 bits.

If you have a Fuzev1 do you have rockbox on it ?

No. I don't know what version I have.

You can tune record settings: different sampling and stereo (although stereo is pretty useless with only one microphone), and I'm also curious because I can hear some noise when playing back audio files on my Clipv2 : this noise occur at the same time the CPU is changing its frequency.

How do you change the recording parameters? In any case, if the ticking is hardware based, changing the recording parameters will have no effect.

EDIT: Which software did you use to normalize ? Audacity seems to "flatten" waves (not sure of the correct term, but a lot of samples are at the same level unlike in your file)

I used Audacity. Use the Normalize function. Do not manually change the gain as you may cause clipping.

[neumannu47]

Originally Posted by JK98

Why are you expecting decent voice recordings from the Fuze? It was not designed primarily to be a recorder. They just threw in a cheap mic and some cheap circuitry to support the voice recording.

You must have missed my earlier post. All that I'm trying to do is to take full advantage of the capabilities of the Fuze. I'm not trying to use it for a purpose other than its intended one. If Sansa had not intended for the Fuze to be a voice recorder, they would not have included a voice recording function.

It does work much better when the player is within 2 or 3 feet of the speaker's mouth. Some people clip a Clip or Clip+ to the speaker's lapel or shirt pocket, and then the recordings aren't that bad.

Of course it does, as does any recording device.

For voice recording, I suggest that you get something that is primarily a recorder. Olympus makes some inexpensive ones that are usable enough for casual use which record in wma.

I have quite a few professional-grade recorders, microphones, and other recording equipment. Recording in WMA, a compressed format, does not give optimal results, particularly for files that need to be edited and then compressed (again). The wav format that the Fuze uses is superior to WMA. The Fuze's bit rate (24kHz) is not as good as CD quality (44.1kHz), nor should it be.

In case you have not investigated, the Fuze has the potential to be an awesome voice-only recorder. The recording format (wave) and bit rate are excellent, the microphone works surprisingly well, and the automatic level control circuitry for the microphone works respectably. The only issue I have found is the infernal ticking noise. Unfortunately, the noise is a deal breaker.

[funman]

Originally Posted by neumannu47

Ambient noise will definitely mask the ticking sound.

I will try again with all doors / windows closed. (I have a small flat )

Originally Posted by neumannu47

You are correct. It is 24K. However, if you look at the properties of the file in Windows Explorer, the bit depth is reported as 16 bits, which is probably correct. It would make no sense whatsoever to record at 32 bits.

You're correct it's 16 bits.

Originally Posted by neumannu47

No. I don't know what version I have.

You can see it in settings -> system -> information.

Originally Posted by neumannu47

How do you change the recording parameters? In any case, if the ticking is hardware based, changing the recording parameters will have no effect.

You can only change it with rockbox, not with the sansa firmware. If changing the parameters change the frequency of the sound it could point to the problem / specific piece of hardware.

Originally Posted by neumannu47

I used Audacity. Use the Normalize function. Do not manually change the gain as you may cause clipping.

Ok I did the same,


Here are results with door closed:

With the Sansa firmware I can definitely hear the tick (though at a lowest volume than your recording).
With rockbox I don't hear it (I tried recording at 0dB and -20dB)

However I'm not sure rockbox records the same way than the Sansa firmware because the PCM doesn't look the same in audacity : the rockbox recording looks more flattened (perhaps reduced sampling depth) : screenshot attached.


neumannu47 if you don't know what rockbox is, check http://www.rockbox.org/ , Fuzev1 is supported by the installer.

If you want I can send you the recordings I made.

[Dreamnine]

Voice recording on DAPs is just a gimmick, an add-on toy.

[neumannu47]

Originally Posted by funman

With the Sansa firmware I can definitely hear the tick (though at a lowest volume than your recording). With rockbox I don't hear it (I tried recording at 0dB and -20dB)

However I'm not sure rockbox records the same way than the Sansa firmware because the PCM doesn't look the same in audacity : the rockbox recording looks more flattened (perhaps reduced sampling depth) : screenshot attached.

Yes, something is different. The audio recorded by the Rockbox firmware is clipped.

neumannu47 if you don't know what rockbox is, check http://www.rockbox.org/ , Fuzev1 is supported by the installer.

I used Rockbox on my Archos 10 players. It made them usable.

If you want I can send you the recordings I made.

Please upload it to http://www.sendspace.com. That would be great.

[funman]

Here are 2 files before normalization, I just removed the part where I open / close the door.

rockbox : http://www.sendspace.com/file/xlru3i
sansa : http://www.sendspace.com/file/veox8q

The hardware has 2 samples depth for recording: 14 bits or 24 bits.

In rockbox we use 14 bits (I thought additional precision was not needed for low quality microphone/FM receiver), so I believe the top bits are 0, hence the clipping.

[neumannu47]

Those two files are definitely very different. The Rockbox file seems to be much quieter. One normalizes with 35 db, the other requires 50 db. It seems that there is something very different about the encoding of the files. Maybe it's the difference in the bit depth. I'm not sure. I did discover that my Fuze is version 0.2.

Thanks for uploading these files. It's an interesting exercise. If you release a version of Rockbox for 0.2, I'll certainly give it a shot.

[JK98]

"I'm not trying to use it for a purpose other than its intended one. If Sansa had not intended for the Fuze to be a voice recorder, they would not have included a voice recording function."

It seems to be intended to be a high quality music player, and a poor quality voice recorder and video player. The best idea is to ignore the voice recording and video playing functions on the player unless you want poor quality.

A pencil might have an eraser on top of it, however a separate eraser will probably perform better. One should not feel obligated to make use of lower quality add ons just because they are included.

"In case you have not investigated, the Fuze has the potential to be an awesome voice-only recorder. "

Huh? It has no mic jack, no voice activation, No recording to wma or mp3, no ability to select the bitrate or sampling frequency. It is about as useful as a voice recorder as a piece of coal is as a pencil. While you might be able to write using a piece of coal and slab of stone, it won't exactly be elegant.

Just my opinion. I wish the voice recording and video was left off the player, and instead some useful playback functions were added, such as variable speed playback between half and double speed with automatic pitch correction.