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Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 1:21 am
by MasterOfPuppets
While trying to record some vinyls to my computer for preservation, this keeps happening. I think the second channel is not there because my adapter is stereo to mono, so that's not the problem.


Image

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 2:08 am
by whomper
i dont see any clipping

you have dc offset
one channel has noise
other one noise until the recording started
at a level maybe 12 db below max - hard to guess with wave view
and small dynamic range

it is really hard to tell anything useful with that waveform view
[aside: i note a bug perhaps in 3.12 where wave and db view do not agree]
so
switch to db view
expand the scale
you will see there is no clipping

turn on the show clipping option
if there were clipping you would see a red line

what was your real question ?

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 4:22 am
by kozikowski
Are you trying to plug something into the Mic-In of your laptop? That's almost always a recipe for overloading and other oddball problems -- unless you're plugging in an actual microphone.

So we're going to need a lot more detailed information of how you got from the phonograph to Audacity. For one thing, the two RCA cables connected to your turntable are not Line-Level audio. they need to go through a specific type of preamplifier before you can use the sound.

Koz

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 4:48 am
by MasterOfPuppets
I'm using the headphone out on my phonograph and sending it straight into the mic in line. I assumed it was clipping because the top of the audio looks flat, but I guess not since it does not go past the top. When I listend to it it sounded like the player was on the incorrect speed. So, what do I need to do to fix this, and thanks for the help so far!

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 5:58 am
by kozikowski
The choices are Low-Level, Mono, Mic-In and High-Level, Stereo, Line-In. Very few laptops cross them or can switch between them. Your laptop has number one and you need number two.

Many people make very good use of a UCA202 device...

http://www.behringer.com/EN/Products/UCA202.aspx

It basically provides your laptop with a very good, stereo, Line-In connection. Hook up your headphone output, switch to it in the Windows Control Panels, Make sure Audacity is using the same sound connection in Audacity Preferences, and go. No more MicPre overloading and no more mono show.

You should really be using Audacity 1.3.12. You're going to get to the point where Audacity 1.2 is either going to stop working or do something messy. 1.2 is no longer supported, updated, or patched.

http://audacityteam.org/download/

Koz

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 1:34 pm
by MasterOfPuppets
Ah, alright, thanks for the input. I'm downloading the update now and will look into that piece of hardware.

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 4:18 pm
by whomper
MasterOfPuppets wrote:... I assumed it was clipping because the top of the audio looks flat, but I guess not since it does not go past the top. ...!
analysis is better than assuming
and that takes factoids

please switch to the db view
you will get a much better idea of what is happening

from your image it looks like you have a signal (dark blue)
that is rather compressed - but it is impossible to tell squat
from that wave view which squishes everything

Re: Audio Gets Clipped No Matter What Input Level

Posted: Mon Nov 22, 2010 5:42 pm
by kozikowski
You might find that the Mic-In electronics in your laptop overloads before Audacity does. This give you the common complaint of a show that will not go over 0.5 in the blue waves no matter what you do, but the overload tools in Audacity do not display.

Microphone amplifiers are looking for signals as much as a thousand times quieter than what you have, so they're set to overload at the slightest error. That and if you have a new laptop, they have automatic volume control and audio conferencing services and that really messes you up -- unless you use Skype. Then, they're fine.

Koz

Re: Audio Gets Clipped No Matter What Input Level

Posted: Tue Nov 23, 2010 12:52 am
by steve
MasterOfPuppets wrote:I'm using the headphone out on my phonograph and sending it straight into the mic in line. I assumed it was clipping because the top of the audio looks flat, but I guess not since it does not go past the top.
I agree that the screenshot does look similar to clipping, though as Koz suggested it looks more like the microphone input is being massively overloaded, so the "clipping" distortion is occurring in the (analogue) input circuitry before it gets to Audacity.

You could try turning down the headphone volume (a lot - almost to nothing) and then adjusting the recording level to increase the signal to Audacity. This may improve the audio quality, but there still remains the underlying issue that headphone output signals are not really suitable for a microphone input and upgrading the sound card with one that can handle a higher signal level would be a much better solution.

Re: Audio Gets Clipped No Matter What Input Level

Posted: Tue Nov 23, 2010 1:03 am
by MasterOfPuppets
Actually, I feel like an idiot right now. I solved the problem by taking the phonograph to my desktop and plugged it into the audio line in. It worked fine, but the adapter (from one size (5.25?) to 3.5) is stereo to mono so I'll need a new adapter. Thanks for all the help!