Problems with mono sound at DVinfo.net

Slava Barouline · December 11th, 2007, 09:57 AM

Hi

I have created MPEG-2 DVD PAL file in Vegas 7e
It sounds OK on my PC, but when I play a DVD on DVD player (not on the PC), the sound is very soft and distorted.

The project uses sound recorded with mono microphone (Rode NTG-2)

The Audio track is stereo, and I render using default DVD PAL template

I tried to combine both chanels and to render audio as mono, but I get distorted soft sound - very similar to what I hear on my DVD

I have a different clip on the same DVD with normal stereo audio track and it plays OK.

What is wrong?

Thanks

Slava Barouline · December 11th, 2007, 10:11 AM

If I change Audio clip Channel to Right (or Left) Only it seems to be OK

Is this the right way to deal with mono sound?

Seth Bloombaum · December 11th, 2007, 10:46 AM

Quote:

Originally Posted by Slava Barouline

If I change Audio clip Channel to Right (or Left) Only it seems to be OK

Is this the right way to deal with mono sound?

Yes.

There can be a couple different problems with summing up two "identical" tracks for a mono mix. If one is even the tiniest bit off the timing of the other... or if one is out of phase with the other, either of these conditions can drastically affect mono compatibility.

The best workflow is to select "right-only" or "Left-only" of a dual-mono track.

In years gone by audio-for-video consoles (mixers) would have a "mono" switch for the monitors so that mono compatibility could be checked instantly.

Mike Brennan · December 11th, 2007, 08:22 PM

agree, Sounds like your track is out of phase, so the signals are canceling each other out. Either select the right or left channel ONLY and use that, or try another copy of the "stereo track" that might be phase accurate.

Is this an instrumental track, or just a "stereo" voicer ?

If it's an instrumental track that was recorded in stereo, many of the instruments will be panned to one side or the other, negating most (or all) of your phase problems on those instruments. Only the instruments that are recorded to both sides (center) of the sound spectrum will be drastically effected by the phase cancellation. This, BTW, was the primary principal of the Thompson Vocal Eliminator !

If what you have is a dual track mono ( All items equal in both sides ) and
one side is 180% out of phase with the other, than disaster will happen !

Hard to say without hearing the problem though. Hope this helps, good luck.
Mike

Slava Barouline · December 12th, 2007, 07:27 PM

I am happy as long as right only wrks for me

It's voice recorded on Rode NTG-2

I sodlered an XLR to 3.5mm adapter and I suspect the signals are 180 out of phase because I probably soldered hot to one channel and cold to the other
;-)

I will get a Beachtek eventually I guess

Gerry Gallegos · December 13th, 2007, 07:05 AM

Just make sure the xlr to 3.5mm is wired in this fashion

XLR 1 = shield on 3.5
XLR 2 = Tip and ring on 3.5
XLR 3 = jumper between XLR 1 and 3

this is the proper way for the cable to be adapted (which unbalances the signal), so long runs are inadvisable. but with a beachtec or similar box you will remain balanced between the mic and the box, so longer runs are ok.

Hope this helps

December 11th, 2007, 09:57 AM	#1
Slava Barouline Regular Crew Join Date: Apr 2007 Location: Canberra, Australia Posts: 47	Problems with mono sound Hi I have created MPEG-2 DVD PAL file in Vegas 7e It sounds OK on my PC, but when I play a DVD on DVD player (not on the PC), the sound is very soft and distorted. The project uses sound recorded with mono microphone (Rode NTG-2) The Audio track is stereo, and I render using default DVD PAL template I tried to combine both chanels and to render audio as mono, but I get distorted soft sound - very similar to what I hear on my DVD I have a different clip on the same DVD with normal stereo audio track and it plays OK. What is wrong? Thanks

December 13th, 2007, 07:05 AM	#6
Gerry Gallegos Major Player Join Date: Oct 2007 Location: Houston, Texas Posts: 262	XLR adapter Just make sure the xlr to 3.5mm is wired in this fashion XLR 1 = shield on 3.5 XLR 2 = Tip and ring on 3.5 XLR 3 = jumper between XLR 1 and 3 this is the proper way for the cable to be adapted (which unbalances the signal), so long runs are inadvisable. but with a beachtec or similar box you will remain balanced between the mic and the box, so longer runs are ok. Hope this helps

December 11th, 2007, 10:11 AM	#2
Slava Barouline Regular Crew Join Date: Apr 2007 Location: Canberra, Australia Posts: 47	If I change Audio clip Channel to Right (or Left) Only it seems to be OK Is this the right way to deal with mono sound?

December 11th, 2007, 08:22 PM	#4
Mike Brennan New Boot Join Date: Nov 2007 Location: South Jersey, NJ Posts: 6	agree, Sounds like your track is out of phase, so the signals are canceling each other out. Either select the right or left channel ONLY and use that, or try another copy of the "stereo track" that might be phase accurate. Is this an instrumental track, or just a "stereo" voicer ? If it's an instrumental track that was recorded in stereo, many of the instruments will be panned to one side or the other, negating most (or all) of your phase problems on those instruments. Only the instruments that are recorded to both sides (center) of the sound spectrum will be drastically effected by the phase cancellation. This, BTW, was the primary principal of the Thompson Vocal Eliminator ! If what you have is a dual track mono ( All items equal in both sides ) and one side is 180% out of phase with the other, than disaster will happen ! Hard to say without hearing the problem though. Hope this helps, good luck. Mike

December 12th, 2007, 07:27 PM	#5
Slava Barouline Regular Crew Join Date: Apr 2007 Location: Canberra, Australia Posts: 47	I am happy as long as right only wrks for me It's voice recorded on Rode NTG-2 I sodlered an XLR to 3.5mm adapter and I suspect the signals are 180 out of phase because I probably soldered hot to one channel and cold to the other ;-) I will get a Beachtek eventually I guess