How Do I improve the quality?

[lisafuturetherapist]

Koz and/or Steve:
How do I make this sound better? Using Audacity 1.3.12 and Windows XP.

I speak into a Sony hand-held ICD-P520 digital recorder, bought for approx $60. There are 2 sensitivity settings on the Sony, low and high. I'm guessing...high sensitivity seems to amplify my voice as I'm recording it.

original.wav

Effect. Noise removal helped to get rid of some of the static. Koz said to set it at 12 - 150 - .15, which I did.

xx after noise reduction.wav

How do I make it sound better? When I play it, some parts of the audio blow out my speakers. You might want to turn it up in order to hear what I mean. How do I make it so it's easy to hear, and understand, without having parts where I blow out my speakers? I've spent the last 2 hours experimenting with different effects, but I don't really understand what I'm doing. Lisa

[steve]

I think the result (xx after noise reduction.wav) is as good as you will get from the source file.

The original file has a sample rate of 16 kHz, which means that the highest frequencies in the recording are limited to 8 kHz (half the sample rate). This is better than "telephone quality", but you will never get a really crisp and clear sound because the sample rate does not support frequencies above 8 kHz. You could perhaps check to see if there's a higher quality setting .... update, I found the manual on-line for the ICD-P520 digital recorder and I see that you already have it set to the highest quality (HQ) setting.

There is also some distortion and resonance to the voice which I think is a limitation of the ICD-P520.

I've listened to the samples on my laptop, headphones and main speakers. The cleaned version is, to my ear, much easier to listen to and the amount of noise removal sounds about right. The sound quality is about what I would expect from a device of this type, and from a quick look on-line $60 looks like a good price.

[lisafuturetherapist]

Steve,
As always, you have been gentle and kind with your words. Respectful and considerate. And helpful. Can we clone you? Koz too?

I read what you wrote, twice, and it makes sense to me. Set the Sony hand-held to "high quality" and "high sensitivity" mic, and that's the best quality I'm gonna get. Got it.

Let me try to ask my Q again. I will try to explain this the best way I know how... Right now, as I play the tracks, I can hear my voice clearly, can understand my words clearly. Every few seconds, I say a word, and the word is so loud that it blows out my speakers. Like in my recording above... I can hear most of the words, but the word "morning" is too loud. If I turn my computer's volume down, so that "morning" is not too loud, then the rest of the track is too quiet.

Is there a way to make it so that every few seconds I don't blow out my speakers? If yes, what are the settings? (Or are you saying that it's the best I'm gonna get with that Sony?) If there's a way to fix it, I'd like to learn how. Thanks again. Lisa

[steve]

The recording has exaggerated frequencies around 1 kHz (1000 Hz). This is the "resonance" that I was talking about. This effect is perhaps being exaggerated further by your speakers as it doesn't sound too bad here.

It is possible to "cut off" the top/bottom of big waveforms, but that will cause very bad distortion.
The way to deal with the problem is to reduce the frequencies that are being exaggerated, and to do that we use the "Equalization" effect.

Here's some ball-park settings for you to try. For best results you may want to tweak these settings.

• Select the audio track (you may want to test this out on a short section before using it on the whole track)
• Effect menu > Equalization
• Click on the "Graphic EQ" button (you will see a lot of vertical sliders).
• Click on the "Flatten" button (this resets all of the vertical sliders to the central position - the graph above will show a flat horizontal line).
• Move the slider that is below the number "1000 Hz" down to the bottom (1000 Hz = 1 kHz)
• Move the sliders either side of the 1000 Hz slider down half way
• Click the OK button.

Equalization.png (46.32 KiB) Viewed 2422 times

[lisafuturetherapist]

Oh, wow! That did it! Much better! I made changes to that one file, and posted it below:

After Equalization.wav

Thanks for letting me know it might just be my speakers, and it's not that bad on your speakers.

I plan to record something else later today... I'll try to equalize an entire track, and see how it goes. Mahalo for your kokua!
Lisa

[steve]

Small speakers, particularly computer speakers will often exaggerate middle'ish frequencies. The issue was noticeable on my headphones and speakers, so it's not "just" your speakers, but your speakers may be making it sound worse than it really is. Anyhow, the "After Equalization" sounds a lot better here. Do you think we'll get through every day of the week?

[lisafuturetherapist]

Do you think we'll get through every day of the week?
Funny. I like your sense of humor. Hey, I'm just happy to get through today. Lisa

[lisafuturetherapist]

Steve and/or Koz:
Quick questions. I record on my Sony hand-held voice recorder. It's model ICD-p520. I go to my computer, & open the computer program that came with the Sony - called Digital Voice Editor. I save the file, from my Sony, to my desktop. Here are my options:
save as it is
auto conversion .wav
44.1 kHz 16 bit stereo .wav
11 kHz 16 bit monaural .wav
mp3 high sound quality .mp3
ICD series .dvf (ICD refers to the model of the Sony)
ICD series .msv (ICD refers to the model of the Sony)

My goal is to use Audacity to open the file and work with it. After I edit the file, I plan to export it as a WMA file, to use in Windows Movie Maker, to make a youtube video.

Question 1: When I save from my Sony, to my desktop, how do I save it?
Question 2: Also,is there a web page you can point me to that will explain the difference betwee 44.1 kHz vs 11 kHz? That way I can learn, but you don't have to type alot. Lisa

[steve]

For best quality, use 44.1 kHz and also, check that the Sony is set to record in HQ mode.

Interestingly the "marketing specification" for this model says that the HQ setting has a frequency range up to 16 kHz, but the User manual says that the HQ setting has a frequency range up to only 6.8 kHz. The audio samples that you have posted suggest that the actual frequency range is 8 kHz using a 16 kHz sample rate.

The highest frequencies possible in digital audio are limited by the "sample rate". The maximum frequency is half of the sample rate, so if you save the recording using a sample rate of 11 kHz, then all frequencies above 5.5 kHz will be discarded, making the sound a bit more muffled.

http://en.wikipedia.org/wiki/Sampling_rate

[lisafuturetherapist]

Hi Steve,
Recorded my voice on Sony hand-held voice recorder.. Mike sensitivity high. Mode HQ recording. Saved to desktop as 44.1 kHz 16 bit stereo .wav Opened Audacity. Imported audio file. Did noise removal, equalization, and amplify -10.
File. Export. Save as type WMA version 2 files. Options. Bit rate.

Question 1: I changed the Bit rate, and I can't remember what the default setting is. What is the original (default) setting?

Question 2: If my goal is to put the WMA into Windows Movie Maker, and make a youtube video... which setting do you suggest to use as the default? Thank you! Lisa