View Full Version : Hardware "hiss" removed?

23rd December 2001, 11:10
Is there any way to apply some hard hack to the line-in source to remove the "hiss" I get from some VHS tapes? I'm trying to encoded "Oh! My Goddess" and "Orguss 2" from VHS but the audio seems to be very soft and there is a lot of background hiss. I would prefer it if I didn't have to go through some other application to take the noise out and then resync in VDub.



26th December 2001, 11:00
Hi !

Discribe the way the hiss sounds.
Is it a lower frequency ? (50/60 Hz)
Is it a higher frequency ?


26th December 2001, 19:32
Thanks for the reply.

Ok, the hiss is a low pitch hiss. Very much a background noise as you get with old CR02 cassette tapes. I hope this helps a bit. If you need a small sample file I can arrage that quite easily.



27th December 2001, 13:36
Sonic Foundry noise reduction directx plugin.
There is a copy floating around.

8th January 2002, 07:22
I was looking also for a solution to remove the hum from analog video. I am getting a 60 hz hum with my video from my tivo. I have recorded programs on my tivo and run the composite video from the tivo to a vcr to fix macrovision. I then run the composite video and audio to a Hollywood DV Bridge. Everything looks alright i guess. Considering I am getting it from a tivo. I am running the audio from the tivo to a stereo system so i can hear my cable on my sound system. I can hear the hum there but its low so you can't notice it unless you put your head up against the speakers. But when you feed it the way i did. tivo-vcr-hollywood dv bridge-computer .... the hum gets louder and also very distracting. I need tools so i can clean the audio up and also instructions. I have an audigy sound board on the computer and it comes with software that i could problably use. Any ideas. I need to dump my tivo bad but want my audio cleaned up so my vcd's will be without the hum... Any help will be appreciated. Thanks,
zumaone :(

8th January 2002, 09:53
Sorry for my late reply but Iīve been very busy over the last few days. If you record from analogue VHS tapes the audio often sounds like old cassettes because they are "saved" the same way to tape.

Try to get either soundforge and the DX noise plugin (VERY EXPENSIVE)
or go for Cooledit 2000 which has also a denoise tool.

But beware: There are the same rules for audio noise reduction as for video noise reduction. You loose almost always some part of the "clean" signal and you have to be very carefull when setting up the filter. For denoising I recommend a HiQ headset directly connected to your sound card.

I think I know what your problem is BUT itīs very hard to explain for me because english is not my native language and I only know the german words for the stuff you might need.

OK, try the following:
Disconnect ALL antenna cables from your VIVO, your VCR, your stereo system (just in case you have a radio tuner) and your PC (in case you have a TV card). If the 60 hz hum is gone, youīre fine. At least there is a cheap solution. There are small components that can be put between each of your antenna cable(s) and your device(s). In german those things are called "Mantelstromfilter" and itīs just a high pass to filter out all low frequencies (like 50/60 Hz power line freqency). Reason for this hum: The ground potential between the shield of your antenna and your power line is different. Usually both should have 0Volts potential but they havenīt. So there flows a small current between both ground potential that causes the hum.

Two other things that could work.
1) Use a cordless transmitter for AV between your VCR and your DV bridge. This galvanicly (hopefully this is written right) disconnects the ground of your antenna (VCR) from the ground potential of your powerline (PC).
2) Try to connect all devices (PC, TV, etc) to the same powerline.

There is also a thing called "Übertrager" which disconnects two signals galvanicly and is just a simple transformator.

Hope this helps a little bit.

Sorry that my english isnīt good enough for that but thatīs pretty technical and even hard to explain in my motherlanguage.

c u,