Need your opinion on noise reduction

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temphr

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Hi all,

I'm a recent new pianoob, and I'd like to record some stuff, but I get some noisy noise.

Soo.. what I have is :
Keyboard Yamaha P95 -> Jack/Minijack adapter -> Minijack (male-male) cable -> My laptop (Asus netbook) through the mic entry -> Audacity.

I tried changing some parameters (input volume, etc.) but in the end, I get noticable annoying noise, which I don't when normally play with a headset. I'd like a very clear sound.

I can't change much on the software part, because Audacity quickly gets signal peaks (saturation) if I increase the input volume to cover the noise. I also tried the Noise reduction tool on Audacity, but the piano loses quite some quality because I recorded at a fairly weak level
So I think I would prefer finding the hardware problem, what should I change to remove that noise (the sound is perfectly clear in my headset).

Ty!
 
You don't describe the noisy noise, hence it makes it more difficult to offer advice. I use a digital piano for recording and have no problems with it either used as a piano or the synth module. The audio signal from a piano has some really unexpected characteristics especially around note decay and reverb if applied on the instrument. You need to describe the sound, better still put a sample of it up here, cos without specifics you might as well ask "what colour is my sofa?"

Good luck

Tim
 
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Hello Ty and welcome,

You are trying to record a headphone output into the mic jack of a laptop. Doomed to failure.

You need an Audio Interface. You could go as cheap/simple as the Behringer UCA 202/222 which is ifininitly better than the built in laptop sound but I urge you to do better.

An AI such a s the M-Audio Fast track pro will not only allow recording of the audio from the keyboard but also the MIDI data and that opens up all sorts of other possiblilities.

Even after you get a usb AI there will be a few nips and tucks to do so get equipped and comeback and see us.

Dave.
 
Not sure if you tried this, but sometimes this noise is related to the battery charger. Try recording audio with the laptop unplugged (if you haven't already :))
 
Hi !

I'm back, and I got my Behringer 202 by now.

The whole stuff works fine. HOWEVER I still have a noise as uncomfortable as if I was recording via the microphone line..

I do not think this comes from the cables quality. When I plug my headset in the Headphone output of the behringer, the sound is still pure. Now at this point, the sound also goes to my laptop's usb entry. I am recording with audacity, and I can't get rid of the noise, even after trying different volume configs.

Halp! :>
ty
 
You get what you pay for - the UCA202 is a cheap audio-to-digital converter. You mention the headphone output at the 202 is good - that's because the sound has not passed through the A/D converter yet.
 
With the utmost respect, you're using the wrong tools for the wrong job.

Headphone outputs are meant for headphones. Headphones have a relatively low input impedance--generally between 16 and about 600 ohms. The input impedance on the UCA202 is listed as 27,000 ohms. Similarly, there's a mismatch in levels between the line level that your 202 is expecting and the headphone level that your piano is putting out.

A piano designed for recording--or, indeed, live use, will have line level outputs. Yours doesn't--just headphones or a built in 6 watt amp.

However, it also has a MIDI input and output and the designers would have assumed that users like you will use that to feed a sequencer (Audacity is NOT a sequencer) with the control of "voices" within your computer.

You MIGHT get rid of (or at least reduce) the noise though the use of a stereo DI box between the piano and the UCA202--but, frankly, I'd try to borrow one for an experiment before spending any money. Otherwise, when adjusting your levels, keep the piano output as low as possible because i suspect the amp in there may be a major source of your noise.
 
Yes the Behringer box is cheap but I have had two and they were pretty good (for those that understand, they both had noise floors of around -85dBFS). Way better than any casssette record using Dolby B and you would expect one of those to make decent recording of a headphone output?

The impedances do not matter, best practice is very low into high. It is possible however that the headphone output is too high and thus internal noise is exaggerated. What sort of levels are indicated in Audacity?

Play a CD through the 202 and see if that is clean then try a radio station. I would suggest BBC Radio3 but I guess you can't get that! To check recorded noise simple run a minute with no signal and listen to the result.

If the Berry unit passes these tests then you have some sort of "operational" problem.

Dave.
 
The operational problem is that a stereo headphone jack is meant for stereo headphones, not to be used as the input to a device expecting a line level source. Yes, you can often get away with it--but "often" isn't always. The only sure fix is a new keyboard with line out or to use the MIDI out and record to a sequencer, not Audacity.

There's nothing wrong with the UCA202 (though it wouldn't be my first recommendation) but the OP is putting together two pieces of mis-matched gear. Sometimes you can get away with it but "sometimes" isn't "always". For example, I can feed the headphone out from my iPhone into my Yamaha mixer and it's fine (Why? I have an app called "Play, Fade, Pause" which is my backup source when doing theatre sound effects). However, if I plug the headphone out from my laptop into the same mixer input, the results are noisy as hell--it's only cured by using a proper interface.
 
Bobbsy said:
The operational problem is that a stereo headphone jack is meant for stereo headphones, not to be used as the input to a device expecting a line level source. Yes, you can often get away with it--but "often" isn't always. The only sure fix is a new keyboard with line out or to use the MIDI out and record to a sequencer, not Audacity.

There's nothing wrong with the UCA202 (though it wouldn't be my first recommendation) but the OP is putting together two pieces of mis-matched gear. Sometimes you can get away with it but "sometimes" isn't "always". For example, I can feed the headphone out from my iPhone into my Yamaha mixer and it's fine (Why? I have an app called "Play, Fade, Pause" which is my backup source when doing theatre sound effects). However, if I plug the headphone out from my laptop into the same mixer input, the results are noisy as hell--it's only cured by using a proper interface.
Click to expand...

There is no essential difference MrB between a headphone output and a line output. In fact on much equipment they are one and the same socket! (the stuff my company sells e.g.).

Reading the OP's posts again I am pretty sure he is getting to strong a signal and this would only be cured with some attenuation (fancy name for a pot' in a tin!) pre the UCA 202.

But yes, for sure an AI with input controls should sort him fine.

Dave.
 
...except it's not working.

It depends on the gear just how similar the line out and the headphone out are. In this case I suspect there are big differences. I can't find a block diagram on the Yamaha site but, since the same level control works for the headphones as for the built in speakers, I have to suspect that the headphone jacks are just hung across the outputs of the 6 watt amps that drive the internal speakers. Just as I can't find a block diagram for the piano, I also can't find noise and distortion figures for the built in amp but I'm willing to bet they're not the best.

I know it proves nothing but, if you look at the Owner's Manual you'll set that Yamaha are largely pushing this as a MIDI device. There are many pages of MIDI instructions and simply some basic "turn it on here and control the volume there" sections for the audio side.

As I said, you might improve things by turning down the level on the piano itself and, perhaps, through the use of a DI as a matching device. But, in this case, the piano is simply not designed to plug into an audio recording system. It's a MIDI device.
 
Bobbsy said:
...except it's not working.

It depends on the gear just how similar the line out and the headphone out are. In this case I suspect there are big differences. I can't find a block diagram on the Yamaha site but, since the same level control works for the headphones as for the built in speakers, I have to suspect that the headphone jacks are just hung across the outputs of the 6 watt amps that drive the internal speakers. Just as I can't find a block diagram for the piano, I also can't find noise and distortion figures for the built in amp but I'm willing to bet they're not the best.

I know it proves nothing but, if you look at the Owner's Manual you'll set that Yamaha are largely pushing this as a MIDI device. There are many pages of MIDI instructions and simply some basic "turn it on here and control the volume there" sections for the audio side.

As I said, you might improve things by turning down the level on the piano itself and, perhaps, through the use of a DI as a matching device. But, in this case, the piano is simply not designed to plug into an audio recording system. It's a MIDI device.
Click to expand...

Yes, I downloaded the manual but could find no figure for the headphone signal level. Bet you are right Bobbs, the feed is a 100Ohms or so slapped on some rather noisy 6W chips!

Dave.
 
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