ADA Depot - A Forum To Support Users of ADA Amplification Gear

Miscellaneous => Discussions => Topic started by: El Chiguete on December 03, 2013, 06:59:18 PM

Title: how do you guys sync video and sound?
Post by: El Chiguete on December 03, 2013, 06:59:18 PM
how do you guys sync video and sound when not micing the speaker but going straight to the computer?
Title: Re: how do you guys sync video and sound?
Post by: rnolan on December 04, 2013, 09:19:17 PM
Not quite sure what you mean.  For recording I take the cab emulated feeds from my MP2 and plug them into a mixer then route the mixer to 2 Digi 001 inputs and record with Pro Tools LE.  I do all the audio monitoring from the mixer so I don't get any sound card latency.  If I miked the speakers I would plug them in the same way but then be in headphone territory to prevent spill.  In which case I have a Behringer headphone amp.  So I spose if I wanted to video myself playing ? I'd take a feed from the mixer into the camera's audio/mic in (if it has one)
Title: Re: how do you guys sync video and sound?
Post by: MarshallJMP on December 05, 2013, 10:56:07 AM
back in the days you used SMPTE but i guess there are more modern methods of doing it.
Title: Re: how do you guys sync video and sound?
Post by: rnolan on December 05, 2013, 06:15:31 PM
We used to put a SMPTE stripe on a tape track and the confuser would synch to that but that was in the sequencing days (creator, notator, early Q Base).  I've a mate who's into video stuff, I'll ask him what they do these days.
Title: Re: how do you guys sync video and sound?
Post by: El Chiguete on December 06, 2013, 01:34:40 PM
But if you are not using and amp and going straight to the DAW?
Title: Re: how do you guys sync video and sound?
Post by: rnolan on December 06, 2013, 11:37:52 PM
Still not quite sure what you are getting at/asking.  That we use cabinet emulated out puts and plug straight into:
If I micked up the speakers the microphones would plug into the above in much the same way except for input levels (line vs mic) so I'm just cutting out the need for a power amp and speakers and mics (not to mention outside noise spill, traffic etc into the mics).  If the cabinet emulation of my MP2 wasn't as good as it is, I would mic the speakers instead and/or if I was after a particular sound (amp/speaker/mic combination) again I'd go to the trouble of plugging it all in. So there is no real difference on the input side (apart from signal levels which you can adjust) between plugging the preamp in directly or micing the speakers.
However, (and maybe this is what you are getting at ??), if you use the computers sound card to record and monitor the sound, there will be latency issues when you want to play back a track(s) and record another track or overdub on a track.  It takes time for the playback to be processed by the sound card and then get to your ears so additional tracks you play/record (which you hear in real time as you play them) will be out of synch with the earlier track(s) by the amount of delay (latency) introduced by the particular sound card.  The sound card/modules included in more recent mother boards (it used to be that the sound card was separate) are usually pretty bad with quite long latency (as were the older sound cards).  The quality of their AD/DA conversion is better than it used to be but stll not that great (depending how pedantic/fussy you are) which is one of the reasons to buy separate dedicated I/O devices (which also generally support more simultaneous inputs and outputs (eg 8, 16, 24 etc) and have much less latency (they all have some latency)).  With 8 inputs you can do a basic live recording (eg bass, electric drum kit, guitar, keyboard, guide vocal) all at the same time (with no latency :-) ) and apart from the guide vocal (I use an SM58 to reduce spill) all the other instruments are direct and not subject to spill so you can get a reasonable result at home and the live tracks are all in synch with each other because they were recorded at the same time.  New tracks and overdubs are still an issue.
On the other hand, (as raved above), if you use a separate analogue mixer for inputs and "ALL" monitoring, all the sounds you hear come from the mixer (both playback and new inputs) at the same time and the sound card I/O latency issue goes away.
When you combine audio and video streams to make a clip, they can be out of synch.  In VLC for example, there are options for delaying one to the other to get them back in synch (it's fiddly but it works).  Audio and video files (eg .wav, .mp3, .flv, .vob etc) are basically a "bucket" within which are stored the encoded audio and video bit streams.  When you play the file, different video and audio codecs are used to play the appropriate stream.
Not sure if all this helps as I'm sill not quite sure what you mean ?  What are you trying to do where synching is an issue ??