Static while recording, sometimes

I’m using version 2.0.2 with Windows 7 on a clean Dell Laptop that may be about a year old. I use Audacity to digitze vinyl. I’m using a NAD PP3i to convert it and a REGA P3-24 to spin them.

I posted here awhile back about a problem I was occasionally experiencing. I get static sound that is ending up in the recorded track(s). This is a link to the thread:

https://forum.audacityteam.org/t/occasional-noise/25186/1

Anyway, I have not solved the issue but narrowed it down bit I think.

I started a record and set the needle in the middle of the disc. I clicked “Start Monitoring” so I could hear when to click the record button. I heard the static, clearly. Without doing anything else I clicked “Stop Monitoring”, and then immediately clicked “Start Monitoring” again. The static was gone. I recorded normally. I think this proves that the NAD converter, sound card etc. is not at fault. I say I think because I have not tried another converter. The only time I ever hear any static or abnormal noise from this laptop is when I use Audacity. And thankfully it is only occasionally, although sometimes it manifests itself when I’m nearly through a side of a 12" vinyl and then I have to scrap the recording and start over.

I really like this program and I actually conducted an A/B listening test using a CDr that I burned compared to the same vinyl record playing. Nothing short of perfect reproduction, to my ears anyway.

Any thoughts or solutions to this problem would be appreciated. It strongly seems to be this program, but I wouldn’t bet the farm on it as stranger things have happened. And I have tried uninstalling and reinstalling.

Thanks in advance for any comments.

When you do these, you don’t have to put the needle on anything. Just start a recording and leave the arm parked. Go away for a half-hour. Set your cellphone to ring. Come back and see if there are any static bursts on the timeline (Control-F to see the whole thing).

One of the fun things about an unstable or marginal system is that you could have changed anything and the static would have gone away.

By the way, you don’t reinstall Audacity by reinstalling Audacity. You can leave Audacity right where it is and modify one file to make Audacity start over from First Birthday/Factory Fresh.

http://manual.audacityteam.org/o/man/preferences.html

Scroll down until it says “reset preferences.”

It would be interesting to leave it recording a parked turntable all night. It might turn out that the static blasts occur at exact timed intervals – like every 90 minutes. You will not be able to export a show that big as anything because of file size restrictions, but you can Save that as a Project.

If the recording doesn’t make it all night, then see if you can figure out when it crashed – and then why. I would expect any relatively new, healthy computer to be able to make a simple capture for six to eight hours. People post here they do it all the time. You can even set the Audacity timer if you wish to take it in smaller chunks like four hours.

This is a lesser known servicing technique. If you can’t fix it, force it to break or make it worse – and take notes how you did it.

“Turns out I get the blast every time Win7 tries to auto-optimize the hard drive…”
“Nothing happened until 9am when the blasts start happening every half-hour.”
“It’s scary. The blast intervals follow the room temperature…”

Koz

Interesting.

I’ll need to reread this post a few times to really get all of it, but I’ll start by recording my parked TT for a couple hours.

Thank you for your reply.

Bear in mind though the “large projects” problem:
http://wiki.audacityteam.org/wiki/Release_Notes_2.0.2#Large_Projects .


Gale

Not sure if this will shed any new light, but here goes…

The trail-in groove of any LP record is silent, but sound from it can still be heard. Sometimes there is the tiniest bit of noise, a small pop or crackle. When this “static noise” condition manifests itself, it seems these tiny artifacts accentuate the static problem.

A few minutes ago I started a record using the “start monitoring” tool. I could hear the static noise. I quickly stopped monitoring, and then started it again before the stylus reached the program. Noise gone.

Not sure why this happens but it isn’t at the point where I can’t use the program Audacity, just an occasional nuisance. I also realize that most folks probably aren’t reading these posts and I may be the only person experiencing these issues.

I appreciate any and all comments and suggestions.

What happens if you don’t monitor at all? Just press Record with software playthrough on (assuming you want it) and accept recording the false starts while you find the LP track? Do you get more static noise events, or less?


Gale

Gale, it sounds like the noise problems I was getting this summer. I never solved them, despite trying cache on/off, no background operations, etc. I’m on the road and not recording anything for a while so I can’t get back to the problem, but in the meantime have upgraded from NT6 to NT6.1 and wonder if that (and the cleaner install) may help. It is (ironically?) nice to know someone else also gets noise gremlins.

Actually, I do. It does not seem to matter if I pre-monitor the source or not. It also seems entirely random.

I just recorded a side of a 12" vinyl. Most of the time I “undo” all of the previous operations (labels, edits etc.). That way, only one Audacity window stays open. I did that this time.

For the second side of this vinyl, I did not click “start monitoring”, rather I just started playing the disc and hit “record”. Lots of static.

I quickly stopped the recording, “undid” the couple seconds I recorded, started the record again and hit “record” again. Perfect.

As I said before, this is an occasional nuisance. Audacity is such a good program, for me anyway, I don’t really feel the need to search for something else. As newer versions are released (I hope) I’ll continue to update and maybe this pesky condition will disappear. As always, thanks for all of the replies. It’s great that you folks are here.

[stunned silence]

Aren’t these erratic problems fun?

I don’t know where to go from here.

Can you post some of the noise? Include normal music leading into a noise segment.

https://forum.audacityteam.org/t/how-to-attach-files-to-forum-posts/24026/1

Koz

You cannot blame Audacity until you record with some other recording program then tell us the problem never happens. Even if that is the case you can still save a WAV from that recording and edit it in Audacity.

Have you increased “Audio to buffer” in the Audacity Recording Preferences? Try 300 ms or more.


Gale

@ Gale.
I increased it as you suggested and will give it a try. Thank you.

@ Koz,
I’ve never saved any of it but I will sometime and see about getting some of it up here. Thank you.

I’ve attached a short 10 second clip of the noise I encounter once in a while. This is the lead-in groove, normally fairly quiet, and the program is just starting.

Again, if I quickly stop and then start the recording again, the noise is gone.

Did the buffer setting make any difference?


Gale

Gale, I know beter minds than mine have worled on this but has anyone been able to tell if these noise problems are from the computer dropping/chopping the USB audio thta’s coming in, as opposed to extra audio being ADDED to the USB audio?

His audio doesn’t sound exactly like mine did (going by memory, mine was more like “picketfencing”) but I was thinking that a big step in troubleshooting this type of problem could come from first asking, if the audio is being “polluted” by other signal being added to it, as opposed to the audio being “dropped” by something making the computer too busy, literally dropping out the audio.

Does that make any sense? Or if it is old news, can you share the answer?

–Red

PS- In my case, the same problem was happening with two distinct audio paths. Whether it was Behringer USB audio, or Creative on the PCExpress54 bus, the problem was the same either way.

If you magnify the noise on the timeline, you find a great many sharp, vertical transitions between segments of music (three in this pix). It’s very unlikely to get that kind of damage in analog land. It has to be during or after the signal becomes digital. It’s very difficult to believe that adding two digital signals together can produce that, but it’s no stretch at all to get that by dropping bits or bad bitstream management. Koz
Screen shot 2012-10-21 at 10.55.41 PM.png

While I rip the waves apart, I found that the show is mono. There are two sound channels there, but they are identical. So if you think you’re capturing the work in stereo, you’re not.

This could drag us straight to wiring problems on your computer.

Koz

USB shouldn’t be acquiring noise from physical sources of noise once the signal is digital. USB can be prone to RF noise at the sampling stage, just before it becomes digital, but I agree Sombunya’s MP3 does sound like some kind of “stream management” problem.


Gale

I use Audacity to digitze vinyl.



I found that the show is mono.

Unless you’re digitizing 78s you have a damaged capture system right out of the gate.
It’s not good to ignore symptoms even if they appear to have nothing to do with the complaint.

Did the buffer setting make any difference?

Gale asked you that multiple times.

Koz

Just a thought: IIRC when I first loaded Vista, the default USB audio settings were for MONO oddly enough. Might be worth checking the advanced properties for the USB sound device to make sure it is set for stereo. (I know, the OP is running Win7, but could still be worth checking.) I think the default is still MONO presuming the sole audio input is the mono mic built into most computer audio these days.

The buffer setting did not change anything.

I am recording in Mono? Not good. I’ll be checking into that right away.