Topic: Brickwalled audio using the audio-in jack on my new cam

[dklein]

If you follow the links of the bottom of the page you'll find that a fixed attenuator is even easier.  I'm with you on the idea of determining the proper dB cut from JB3>camera and then running a fixed attenuator.

I don't know your camera but if there's any way to switch to a line level input, that might eliminate the extra gain.  There could also be impedance matching issues with a microphone input.  I'm sure you've considered it but why not add sound later, from your JB3 source?  Synch problems?

[Genghis Cougar Mellen Khan]

If you follow the links of the bottom of the page you'll find that a fixed attenuator is even easier.  I'm with you on the idea of determining the proper dB cut from JB3>camera and then running a fixed attenuator.

I don't know your camera but if there's any way to switch to a line level input, that might eliminate the extra gain.  There could also be impedance matching issues with a microphone input.  I'm sure you've considered it but why not add sound later, from your JB3 source?  Synch problems?

I think you must have forgot the link. 

As far as I know only pro models EX the GL-2 have line level inputs. You can always add the sound later, I'd wish whoever the best of luck trying to get decent results without it looking like a kung-foo movie (yes, sync issues). If you're recording the audio with an audio recorder, why sweat over very very minimal noise by utilizing the recorders headphone out? If you look at the input specs on typical vid camera mic inputs you'll realize that they aren't exactly the cleanest input, in many cases worse than the noise introduced by the headphone out on recording devices.

[dklein]

I think you must have forgot the link. 

As far as I know only pro models EX the GL-2 have line level inputs. You can always add the sound later, I'd wish whoever the best of luck trying to get decent results without it looking like a kung-foo movie (yes, sync issues). If you're recording the audio with an audio recorder, why sweat over very very minimal noise by utilizing the recorders headphone out? If you look at the input specs on typical vid camera mic inputs you'll realize that they aren't exactly the cleanest input, in many cases worse than the noise introduced by the headphone out on recording devices.

sorry - I meant the links that I put on the how-to page

http://www.uneeda-audio.com/pads/
http://www.tkk.fi/Misc/Electronics/circuits/line_to_mic.html
http://www.ethanwiner.com/gadgets.html

As far as synching goes, it's not too bad.  You really only have to figure it out once to determine the clock differences between your JB3 and camera.  I'm reasonably confident that the V3 (optical) > JB3 will sound better than passing analog thru the JB3 and into the cameras preamp/a>d.

Here's an idea on synching - if you record with the JB3 at 44.1, you're gonna need to resample to 48k for a dvd.  The trick is to determine the right resampling rate (close to 48k but not 48k) that will synch them, and then set the header to 48k.  Here's the thread http://taperssection.com/index.php?topic=35629.0

Having done it a few times now, I can tell you it works very well and the R8Brain freeware that I refer to does the job quite nicely if you don't want to play around in a wave editor.  And after you've done it once you have your 'magic number' for synching the 2 recording devices.

[Genghis Cougar Mellen Khan]

I think you must have forgot the link. 

As far as I know only pro models EX the GL-2 have line level inputs. You can always add the sound later, I'd wish whoever the best of luck trying to get decent results without it looking like a kung-foo movie (yes, sync issues). If you're recording the audio with an audio recorder, why sweat over very very minimal noise by utilizing the recorders headphone out? If you look at the input specs on typical vid camera mic inputs you'll realize that they aren't exactly the cleanest input, in many cases worse than the noise introduced by the headphone out on recording devices.

sorry - I meant the links that I put on the how-to page

http://www.uneeda-audio.com/pads/
http://www.tkk.fi/Misc/Electronics/circuits/line_to_mic.html
http://www.ethanwiner.com/gadgets.html

As far as synching goes, it's not too bad.  You really only have to figure it out once to determine the clock differences between your JB3 and camera.  I'm reasonably confident that the V3 (optical) > JB3 will sound better than passing analog thru the JB3 and into the cameras preamp/a>d.

Here's an idea on synching - if you record with the JB3 at 44.1, you're gonna need to resample to 48k for a dvd.  The trick is to determine the right resampling rate (close to 48k but not 48k) that will synch them, and then set the header to 48k.  Here's the thread http://taperssection.com/index.php?topic=35629.0

Having done it a few times now, I can tell you it works very well and the R8Brain freeware that I refer to does the job quite nicely if you don't want to play around in a wave editor.  And after you've done it once you have your 'magic number' for synching the 2 recording devices.

Thanks for the links.

I still wish anyone the best of luck to sync the 2 sources without having to manually cut and match, you might be able to get it close, but sources still drift, esp when tape is involved. For resampling, I thought the jb3 did 48kHz?

"I'm reasonably confident that the V3 (optical) > JB3 will sound better than passing analog thru the JB3 and into the cameras preamp/a>d"

Agreed, but I wasn't suggesting passing through the jb3 analog, just sending the audio that' being recorded (v3 > opti > jb3) out to the camera via the headphone out. I'd do the headphone out > camera mic in and if the results are sub par then play around with all that resampling, synching, editing etc...

[Tony B]

Thanks for the responses guys...great discussion, and good links too.

I'd imagine that further down the line, I'll try syching up my audio with the vid in post. Yes, the JB3 does do 48kHz. For now, as I said, I'm in the first stages of doing this, and Genghis's option is a bit more appealing to start with.

t's


TB

[Genghis Cougar Mellen Khan]

Thanks for the responses guys...great discussion, and good links too.

I'd imagine that further down the line, I'll try syching up my audio with the vid in post. Yes, the JB3 does do 48kHz. For now, as I said, I'm in the first stages of doing this, and Genghis's option is a bit more appealing to start with.

t's

TB

T's for the rest of you.

Thanks dklein for the links too...

[dklein]

I still wish anyone the best of luck to sync the 2 sources without having to manually cut and match, you might be able to get it close, but sources still drift, esp when tape is involved. For resampling, I thought the jb3 did 48kHz?

If you follow that thread, it's about how to synch without cutting.  With R8brain you can resample down to decimal places - accurately enough to synch perfectly.  The thing I don't like about cutting is you're almost never synched (it's like servo control on motors).

"I'm reasonably confident that the V3 (optical) > JB3 will sound better than passing analog thru the JB3 and into the cameras preamp/a>d"

Agreed, but I wasn't suggesting passing through the jb3 analog, just sending the audio that' being recorded (v3 > opti > jb3) out to the camera via the headphone out. I'd do the headphone out > camera mic in and if the results are sub par then play around with all that resampling, synching, editing etc...

Even with headphone out it's passing thru a lot of JB3 analog electronics (it must be using the JB3  for d>a and an analog path if the levels are controllable).  Now if you had a V2 you'd also have an extra set of RCA outs on your preamp    But in either case, the camera is still doing some gain and a>d (again).  That's stuff I'd much rather have done by the V3 directly.

But hey - there are many ways to bake this cake!

[Genghis Cougar Mellen Khan]

Even with headphone out it's passing thru a lot of JB3 analog electronics (it must be using the JB3  for d>a and an analog path if the levels are controllable).  Now if you had a V2 you'd also have an extra set of RCA outs on your preamp    But in either case, the camera is still doing some gain and a>d (again).  That's stuff I'd much rather have done by the V3 directly.

But hey - there are many ways to bake this cake!

A huge complicated multi-layer cake. when I've shot video, I've always sourced my audio using the of either my v3>m1 or sbd>m1 setup through the headphone out. I have intentions of putting some of the better shows on dvd with the dat sourced audio (possibly post matrixing etc) and matching it up with the video for the best results. For now at least the audio on the videos is far better than just running the camera with no external sound at all. Your point that the camera is still doing some gain and a>d is a very good point, the only way around it is to add in the audio after the fact. 

For now I'm utterly frustrated at the pc processing speeds and coutless dvd authoring/editing programs out there, most of that is on the shelf to be played with at a later date. (hopefully some day) 

[Tony B]

For now I'm utterly frustrated at the pc processing speeds and coutless dvd authoring/editing programs out there, most of that is on the shelf to be played with at a later date. (hopefully some day) 

Procrastinators unite! I have enough of a time lugging my crap into a venue and getting a good recording 

[Genghis Cougar Mellen Khan]

For now I'm utterly frustrated at the pc processing speeds and coutless dvd authoring/editing programs out there, most of that is on the shelf to be played with at a later date. (hopefully some day) 

Procrastinators unite! I have enough of a time lugging my crap into a venue and getting a good recording 

I'm not procrastinating, it's the pc speed and software to blame. 

Ditto on lugging in all that crap...

[Mark]

FWIW, I didn't read the above posts, but when we applied an audio patch to a camcorder, we ended up doing this:

Ran line out on my D7 but dropped the volume to about 6-7 on the 20 scale.  This was field tested.  Yes, we brickwalled our first time out.  Problem was that we think the camcorder's mic is still active.  Reason is that the DVD that we created from the video does not match the audio sound.  The bass is stronger, and the highs are diminished compared to the audio.

[Genghis Cougar Mellen Khan]

FWIW, I didn't read the above posts, but when we applied an audio patch to a camcorder, we ended up doing this:

Ran line out on my D7 but dropped the volume to about 6-7 on the 20 scale.  This was field tested.  Yes, we brickwalled our first time out.  Problem was that we think the camcorder's mic is still active.  Reason is that the DVD that we created from the video does not match the audio sound.  The bass is stronger, and the highs are diminished compared to the audio.

Your volume control has no effect on your line out , line out level is the same as your line in level, you can't change it.

[allan]

ive never had any luck with the mic in on my video camera either, i decided to just use my regular audio recording gear and sinc it together later...

when are we gonna get to see this MEC video?

[ethan]

Picked up a Canon Optura 50, and tried to tape a concert here a few days ago (Magnolia Elec Co.), and the results were less than stunning. My setup includes the following:

Canon Optura 50
KM184's
V3

I ran my mics into my preamp, then to the Optura out of the V3's XLR outs (Two XLRs>single 1/8" mini stereo plug), as well as my JB3 (via the digital optical line). The audio on my recorder turned out great, but the audio on the camera was brickwalled...distorted and unlistenable.

Does the camera have any specs? Like input impedance? Could you post them?

[Genghis Cougar Mellen Khan]

ive never had any luck with the mic in on my video camera either, i decided to just use my regular audio recording gear and sinc it together later...

when are we gonna get to see this MEC video?

Did you ever try anything mentioned above?