Hollow sound

alfredsvideo wrote on 12/22/2003, 1:28 PM

My first camera, when I first got into this hobby, was a Sony 5000. It was a benchmark in it's day, but then followed by the 6000 which was capable of reading and writing time code. I'm not too sure how I had created this particular sound problem, but I think it was by using, "Mix", instead of "Stereo" or "PCM" when I was outputting to VHS. There was a switch on the camera for enabling these features. The result was that I ended up with audio that sounded like it was coming through a long tube. Hollow, if you like. It is very pronounced. I am now in the process of archiving all my 15 years of video, but there are a couple of tapes that contain this problem. Any ideas on how to overcome it?
I have Sound Forge 5.0 and I could experiment, I suppose, but thought maybe you guys could save me some time. Thanks.

Comments

farss wrote on 12/22/2003, 11:07 PM

I tried to cure a not dissimilar problem. SPOT did suggest you could do it with acoustic mirror run in reverse but finding the right settings would be very tedious.

If you've got the time it might be worthwhile because I'd assume unlike my problem yours will be constant so once you've got the magic numbers they'll work for all the audio.

TorS wrote on 12/23/2003, 8:02 AM

farss,
I don't think he'll have Acoustic Mirror, being on Sound Forge 5.

alfred,
If you upgrade ot at least 6.5 you'll get Accoutsic Mirror thrown in. You should be able to read up on it somewhere on the Sony site (click "products" above here, for a start.

Short of that, I'd experiment with copying the sound to several tracks and try squeezing each very tight with EQ and compression and different settings, and then combining them in the final mix.
Tor

Spot|DSE wrote on 12/23/2003, 9:00 AM

You can always use lots of EQ's, applied separately, just as TorS suggests. I heard a project a guy did, where I gave up on the audio after a while, because it was so horrendous. There was more boom than there was source.
He spent about a week, tweaking with an EQ, adding/subtracting specific values, noting each change so he never hit the same freq's twice, and while it certainly wasn't stellar, it was a psuedo usable product in the end. Tenacity, the best plugin there is... :-)

LarryP wrote on 12/23/2003, 10:33 AM

The hollow sound is often caused by the same sound being added together with a slight delay between the sources say left and right channels. At certain frequencies the sound will cancel out causing the hollow effect you mention. For example a sound reaching 2 microphones 7in. apart will cause a notch at 1000hz.

If you still have access to the stereo signals try using only the left or right channel. Otherwise this being a time domain problem it is difficult to correct.