Subject:sampling rate; CD labels

Posted by: joejon

Date:3/30/2004 10:38:37 AM

When I capture video, then save it as a .wav file, the sampling rate is 32,000. So I assume that's what my video camera records at. After doing some edits, I sometimes get an error message when I try to save. For some reason, when I switch it to a 44,100 sample rate (in File>Properties) and save, it's okay. But then my music plays too fast. I then change the sample rate back to 32,000 and it saves and plays okay. This seems like a strange thing to have to do. I read that you can change the sample rate also by going to Process>Resample. Can anyone explain why it won't let me save at the original sampling rate? Which is a better method to use - changing it in File>Properties or Process>Resample? I know it needs to be at 44,100 before burning to CD, but when I use Vegas to lay out my songs and then Render As (.wav), it changes the sample rate to 44,100 and the songs seem to play just fine and at the right speed. This is confusing to me. When should the sampling rate be changed to 44,100 and how?
I'd like to ask if anyone has information on CD/DVD label kits. I've read good and bad things about them. The bad being that the glue can cause problems. If anyone has used these types of labels, what brand do you use? I bought a Fellowes Neato kit on a rebate, but I hesitate to use it. Thanks for any input.

Subject:RE: sampling rate; CD labels

Reply by: Iacobus

Date:3/30/2004 11:36:40 AM

I would resample it to 44.1 kHz via Process>Resample before doing anything else.

I believe Vegas is upsampling on the fly based upon the general overall project sample rate.

Generally, I don't think using labels is a good idea. I'd probably suggest silk screen or thermal printing (which can be expensive) or just using a soft-tipped marker.

Iacobus
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RodelWorks - Original Music for the Unafraid
mD's ACIDplanet Page
Guitars 4 Kids

Subject:RE: sampling rate; CD labels

Reply by: Rednroll

Date:3/30/2004 1:32:23 PM

Your problem does seem a bit odd. Sounds like a possible bug to me. For some further explanation between the properties settings and the resample process. If you want to change the sampling rate from 32Khz to 44.1Khz, use the resampling tool. Changing the value in the properties does not change the files actual sampling rate of the audio. It changes the value that get's reported to the play back device to let it know, what it's sampling rate is. This is useful, because sometimes like you noticed a file will playback at the wrong speed. That's because the files actual sampling rate may be 32Khz, while it's properties is telling the playback device it's 44.1Khz. So you go into the properties setting and change this value to 32Khz and it plays back at the correct speed. Using the resampling tool, will resample the audio data and then update this information into the properties.

Subject:RE: sampling rate; CD labels

Reply by: joejon

Date:3/31/2004 12:17:21 PM

So if I use Process>Resample, my file will be 44,100 and it will play at the correct speed (as the original)? Can you explain how that works? I want to understand this better. Thanks

Subject:RE: sampling rate; CD labels

Reply by: Geoff_Wood

Date:3/31/2004 2:36:21 PM

Changing the Properties just dicks with the wav header. The data will then be played back at 44K1 rate, will will end up fast.

You need to RESAMPLE your 32K wav to a 44K1 wav, then save.

geoff

Subject:RE: sampling rate; CD labels

Reply by: Rednroll

Date:3/31/2004 3:03:15 PM

If the file is originally playing back at the wrong speed, the process>resample will not fix the playback speed. It will "resample", the original file. So if it's currently at 32Khz and playing back at the wrong speed, using the resample to 44.1Khz, will resample the file, and now it will be a 44.1Khz file playing at the wrong speed. If it's a 32Khz file playing at the wrong speed and it "should" be a 48Khz file, using the properties to change the header information to 48Khz, and will make it so the file plays back at the correct speed. Now, if you want this file to be 44.1Khz, because you're transferring it to CD, you can then use the PROCESS>RESAMPLE function to have Sound Forge resample that file, so it's now a 44.1Khz file playing at the correct speed.

Clear as mud yet?

Subject:RE: sampling rate; CD labels

Reply by: rraud

Date:3/31/2004 4:15:23 PM

Labels:
I have been using the Neato labels for about 4-5 years. My clients nor I have have experienced any problems. Care must be taken to apply them absolutly centered with no bubbles or creases, ect.
That said however, for archival CDs and masters going to duplication or replication I do not use them.

Subject:RE: sampling rate; CD labels

Reply by: joejon

Date:4/8/2004 2:52:39 PM

It was recommended that I resample my audio files from 32KHz to 44KHz before doing the other processing steps. My new video camera records at a 48KHz sample rate. Should I resample first as I do for the 32KHz files or after the other processing steps? It seems to me that it would be better to do all the processing and then resample to the lower rate (44), but maybe I'm wrong. Thanks.
Does anyone have problems burning Imation CD-R music CD's? It seems like I get a lot of errors and have to keep trying until finally one burns okay. I use 1x or 4x burn speeds, so that shouldn't be.

Subject:RE: sampling rate; CD labels

Reply by: drbam

Date:4/8/2004 8:32:45 PM

<< I use 1x or 4x burn speeds, so that shouldn't be. >>

Not necessarily. Some burners just seem to prefer certain media - especially older models. It makes sense to experiment with some different media and see if you still have problems. If so, then you may have a problem with your burner. Make sure to update the burner's firmware. If you find a brand of media that works well, then stay with it and avoid the temptation to try something else - "if it works, don't fix it" applies here. ;-)

drbam

Subject:RE: sampling rate; CD labels

Reply by: joejon

Date:4/17/2004 1:16:21 PM

Why does SF give me error messages when I try to save a .wav file with a sampling rate other than 44K? Some of my older video was at a 32K rate and I now resample right away, but if I don't I sometimes (sometimes not) get an error message and when I change the sampling rate either in properties or resample option, then it saves it. Now, my video is a rate of 48K, so I resample after all my other processing. But I sometimes get the error message (sometimes I don't ) and when I change it in the properties to 44K, then save, then change it back to 48K and then save, it works. This is very strange and seems like a stupid way to do this. What is the deal with sampling rates and saving files? Why does SF save when I change the rate in the properties?
Thanks

Subject:RE: sampling rate; CD labels

Reply by: SonyTSW

Date:4/17/2004 9:19:34 PM

> When I capture video, then save it as a .wav file, the sampling rate is 32,000

Check your video camera owner's manual. Your audio mode setting may be set as 12-bit . You may want to change this to 16-bit if there is an option to do this.

The 12-bit setting (often the factory default) is for recording at 32 kHz with two separate stereo channels. The second stereo channel is intended for dubbing later with narration, music, etc.

The 16-bit setting is for only one stereo channel, but it may record at a higher sample rate. My Sony TRV-950 records audio at 48 kHz when audio mode is set to 16-bit.

Just a word of caution. If you do change this setting, don't do it in the middle of a tape (or be very careful about your captures). If your capture to an AVI file includes this change in sample rate within a single clip, it is likely that Vegas won't be able to read the audio. The AVI reader requires a constant sample rate for the entire duration of the audio stream within a clip.

Subject:RE: sampling rate; CD labels

Reply by: joejon

Date:4/18/2004 2:20:47 PM

Sony, Your response did not really answer my question. My old video camera, which I don't use anymore, but I have tapes that I recorded using it, had a sample rate of 32K. My new camera, which I have set to 16-bit, records at 48K. By the way, having 16bit displayed in the viewfinder all of the time is very annoying. Sony should change that. What the problem is, as I described in my 4/17 post, is that SF sometimes will give me an error message if my audio file is not set to 44K. I change the setting in Properties, Save, then change the setting back to 48K, Save and it saves fine. Very strange. What is the explanation for this? I keep my file at 48K until most or all of my other processing is done, and then I resample. I could resample 1st, but I don't want to do that, and I shouldn't have to.

Subject:RE: sampling rate; CD labels

Reply by: SonyTSW

Date:4/18/2004 8:28:38 PM

Sorry, I realize I didn't fully answer your question. I was just wondering why you had recorded audio at a sample rate lower than 44.1 kHz. As it is easy to do this with the default factory settings on many video cameras, just wanted to make sure you were aware of this.

Are you using Sound Forge 7.0a?

p.s. You may be able to turn off the display of "16BIT" on your camera. Mine has a button labeled "Display/Touch Panel" that toggles the display of the screen indicators. Check your owner's manual.

[Edit]: Turns it off on the LCD screen but not in the viewfinder. I sure don't know it why isn't the same in both places...

Subject:RE: sampling rate; CD labels

Reply by: joejon

Date:4/19/2004 7:08:47 AM

Sony,
Yes, I am using SF 7a. I get the same error message when I have audio recorded at 48K with my present camera. The strange thing is that sometimes it saves just fine with different sampling rates, other times it doesn't and I get an error message. You would think it would be consistent. I wish I would have noticed if it's after doing certain kinds of processing/editing, if that makes a difference, but I don't know. That shouldn't really make a difference though. It usally happens after I've done quite a bit of noise reduction, click removal, smooth/enhance, fades, copy other channel, etc. and then try to save. But like I said, sometimes I get an error msg. and sometimes it saves just fine.