LP recording slow playback

[randes2000]

I am using Audacity 1.26 and recording an LP via the aux out of an amp to the line in of my sound card. My machine is a Pentium 4 @3.0GHz with 3Gb of RAM. I have over 100GB available on the hard drive I am recording to. The recording and playback device are both set to the sound device, SoundMax Digital Audio, the integrated sound device. The OS is XP SP3. I do not have Software Playthrough checked. During recording the music sounds normal, but playback is slower in speed. I tried increasing the speed by 8.3% as indicated by another post and that fixed the playback. Has anybody worked out a solution to this or is my setup the culprit? I am only running Norton Antivirus during recording.

[kozikowski]

Does it do that with Windows Sound Recorder (close Audacity).

Windows Sound Recorder
Start -> Programs -> Accessories -> Entertainment

Koz

[randes2000]

I recorded the full 60 seconds in Sound Recorder and saved it as a WAV file. Playback of that WAV file was normal.

[steve]

I recorded the full 60 seconds in Sound Recorder and saved it as a WAV file. Playback of that WAV file was normal.

Good. That shows that your computer sound system is working correctly (at least for 60 seconds).

I tried increasing the speed by 8.3% as indicated by another post and that fixed the playback.

hat is very close to the difference between a sample rate of 44.1 kHz and 48 kHz. Did you change the sample rate of the recorded track by any chance?

Can you reproduce the problem? If so, please describe a step by step method so we can see if we can reproduce the problem as well (and hopefully come up with a solution).

[randes2000]

The sample rate is 44.1 kHz. The slow playback has occurred for both LPs I have recorded. Except for this minor annoyance, I have been able to Label the tracks, Export Multiple as WAV files and then burn the WAV files to an audio CD via Nero. The sound is great. If you come up with a solution great, otherwise I can work with increasing the speed the 8.3%. The hard drive I am using is SATA and not the drive the OS is loaded on. Step by step is pretty much right out of the Audacity manual. I made the inital settings, record each side of the LP using the Pause button while I turn the record over. I then play back a portion of the recording, find it to be slow and then apply the 8.3% speed increase. Add a label track, add labels for each song and then export multiple.

[steve]

I then play back a portion of the recording, find it to be slow and then apply the 8.3% speed increase

Oh... ? trying to get a clear picture here... So you are saying that the playback speed is not constant, but varies over the course of the recording?

[randes2000]

First, thanks for the time to help me out. The playback speed does not vary. It is the same "degree" of slowness (lame terminology) over the entire track. I apply the 8.3% speed increase to the entire track (about 40 minutes of recording). Here are my Preferences settings: Audio I/O: Playback Device>SoundMAX Digital Audio, Recording Device>SoundMAX Digital Audio, Channels> 2(Stereo), Play other...>not checked, Software Playthrough...>not checked Quality: 44100Hz, 32-bit float, Fast Sinc Interpolation, High-quality Sinc Interpolation, None, Triangle File Formats: Read directly from the original file>is selected, Uncompressed Export Format>WAV (Microsoft 16 bit PCM), OGG Quality>5(it's greyed out) Spectrograms: FFT Size>256-default, Maxiumum Frequency>8000 Directories: Free Space>120.2Gb
After creating a directory for the project and setting the recording levels, I start the LP, press record, press pause at the end of the LP's first side, turn the LP over and start playing, press pause(resume) and then press stop at the end of the second side. At this point, if I go to any point in the recording and press play, the playback sounds slow.
On my first attempt, I didn't realize it was slow, exported the tracks and burned an audio CD. Whe I played the audio CD, I realized the recording was slow and then found the source to be the Audacity recording.
I don't have any empty PCI slots to try another sound card, so I'm hoping for a software fix.

[steve]

One possibility is that your sound card is running internally at 48kHz, and is not handling 44.1 correctly.
Try changing the quality settings in "Preferences" to 48000 Hz.

Note that if you import or open an existing file into a project, it may cause Audacity to change the project rate, so check that the project rate in the box in the lower left corner of the main Audacity window says 48000.

Does that now record and play at the correct speed?

If that works, you just need to remember to change the project rate back to 44100 before you Export so that you have the correct sample rate for your CD.

If this still does not work, try upgrading to Audacity 1.3

[randes2000]

stevethefiddle,
Wow, that did it. Playback was normal using 48kHz. The only issue now is that I cannot export at 44.1kHz. The resulting WAV files had "carry-over from the beginning of the next track....strange. I tried exporting at 48kHz and all is well. Yeah, I might use up a bit more space on the CD, but I'm only recording a single LP to each. I tested importing the CD into itunes, and it was fine with it. Time to digitize all those old LPs..... Thanks for the help.

[kozikowski]

<<<Export so that you have the correct sample rate for your CD.>>>

Or not. All the clips and test music on my site are 48000. They have no trouble at all playing at the correct speed everywhere or burning to a CD using Windows or Mac CD authoring software.

<<<Yeah, I might use up a bit more space on the CD>>>

No, it doesn't. CD Authoring software is required to convert to 44100. This is why I think you're performing one too many tasks.

There is something evil about the way Audacity handles cross sample rates. I bet Audacity is producing a sound file header at one sample rate, but the actual sound is at another. I'd kill to know why it's doing that so we can turn it in as a bug.

I wonder if the 1.3 people have this problem....

Koz