Laserdisc capture - general thread

[pipefan413]

Just discovered something rather troublesome about one of my players: the analogue audio recorded from it contains audible noise from the disc spinning. As in, the vibrations of the player are actually passed to the recording.

This does not appear to be the case for my other players, thankfully, but it's irritating because this one is the most convenient for capture due to having two sets of outputs (so I can use one to monitor and one to record, or both to record through different devices). I didn't record THE EXORCIST from it, so that's fine, but I'm going to have to redo PINOCCHIO for at least a 3rd time...

[pipefan413]

Just discovered something rather troublesome about one of my players: the analogue audio recorded from it contains audible noise from the disc spinning. As in, the vibrations of the player are actually passed to the recording.

This does not appear to be the case for my other players, thankfully, but it's irritating because this one is the most convenient for capture due to having two sets of outputs (so I can use one to monitor and one to record, or both to record through different devices). I didn't record THE EXORCIST from it, so that's fine, but I'm going to have to redo PINOCCHIO for at least a 3rd time...

Right. Little test for you.

Same LaserDisc recorded mere moments apart from 3 different LaserDisc players. Everything else is identical: same capture device, same recording levels, same sample rate and bit depth, and so on. Obviously no cleanup or repairs here, this is straight out of the player, as it comes.

All of them sound pretty bad compared to properly studio recorded PCM, but the thing that I find alarming is how different they are. All three actually seem to be reproducing quite a lot of noise from the player itself, including *the vibrations caused by the spinning of the disc as it plays*. It's just that the noise is different depending on the player; the noise I was hearing specifically in that particular capture doesn't appear in the other captures but other noises unique to each player do occur in all 3 cases.

I figure that perhaps the best way to do this is to line them up sample-for-sample and flick between them so I stuck them all in an .mka container so you can do exactly that.

These are intentionally not labelled but I know which player is which. I'm really curious to find out which you think generally sounds the best out of the three. It's also made me want a more expensive player again, which is something I couldn't afford before and certainly can't now, so that's extremely unfortunate...

To avoid colouring opinions, I'll not tell you what I think just yet. But please do tell me what you think. PM me for the file!

Spectrograms for the curious:

[BusterD]

Hmm, distressing. I'm actually monitoring an analog capture myself at the moment (LP and not LD though), but I hope that neither of my players would be affected at all. Double checked a couple captures, and the noise floor for LD analog seems about as low as can be for analog, as I have to zoom in really far to see any waveforms, and can't hear anything with the volume turned all the way up.

My players are an HLD-X9 and a DVL-919, so not lower end players at any rate, and I haven't noticed any problems so far, but nothing like a bit of paranoia to get one to re-think all their captures...

[pipefan413]

Hmm, distressing. I'm actually monitoring an analog capture myself at the moment (LP and not LD though), but I hope that neither of my players would be affected at all. Double checked a couple captures, and the noise floor for LD analog seems about as low as can be for analog, as I have to zoom in really far to see any waveforms, and can't hear anything with the volume turned all the way up.

My players are an HLD-X9 and a DVL-919, so not lower end players at any rate, and I haven't noticed any problems so far, but nothing like a bit of paranoia to get one to re-think all their captures...

Mine are all midrangers but all the info I had re. analogue audio output suggested this shouldn't really make a big difference. Turns out it does, at least if you check with headphones. It isn't obvious over speakers but that's probably partly because the noises actually coming directly from the player (as in, the vibrations caused by the disc spinning and so on) are loud enough that they drown out the much quieter residual noise coming out of the speakers.

I think for me to be content with my archival of analogue audio I'm going to have to somehow find a chunk of money I don't really have and throw it at a high end player. I could attempt to sell one of my existing ones to help fund that, but they're currently all useful to me for different reasons and I don't really want to throw that out the window; it'd be tricky to choose which one to sell. Equally, though, they already take up a lot of space so I dunno where a 4th would go...

[zoidberg]

Are you saying you can hear the player vibrations within a captured file, or just during playback? Please send me the file so I can take a look

[pipefan413]

Are you saying you can hear the player vibrations within a captured file, or just during playback? Please send me the file so I can take a look

Actually in the recordings. Same noise the player makes. Each one's different but all have some degree of noise. Incoming!

[pipefan413]

Just checked a recording from a Runco LJR-II and even in that you can hear the disc spin vibrating the player! I even commented on that some time ago when I was comparing my capture of the same disc to this one from the Runco, but I didn't yet realise what the noise actually was. Holy crap. In my captures of THE EXORCIST, that low rumble/hum that's audible in the Runco capture can't be heard, but the player I used for my capture has its own different noise (I'm not telling you which one in case that changes your opinion of this test but you can probably tell from the test recordings I prepared for PINOCCHIO).

I guess this is yet another quirk of the format that I'm discovering for myself here! As with some other things, I'm surprised this hasn't already been well documented, but I guess we're dealing with a very specific niche here.

[zoidberg]

The sample is from an analogue only LD with no CX noise reduction encoding, the 'rumble' sounds to me to be the surface noise of the disc. Analogue non-CX discs are somewhat noisy and things like dirt, scratches and pressing defects (dropouts, inclusions) will be heard, much like a vinyl record.

You would almost certainly hear this noise even on a high-end player, the main thing with the top players is they don't introduce noise of their own so the SNR is better. But if the noise is inherent to the pressing then it will reproduce it.

[pipefan413]

You would almost certainly hear this noise even on a high-end player, the main thing with the top players is they don't introduce noise of their own so the SNR is better. But if the noise is inherent to the pressing then it will reproduce it.

Yeah, given that it's audible in somebody else's Runco LJR-II capture of THE EXORCIST, it sure seems like it! That seems to be held up

The sample is from an analogue only LD with no CX noise reduction encoding, the 'rumble' sounds to me to be the surface noise of the disc. Analogue non-CX discs are somewhat noisy and things like dirt, scratches and pressing defects (dropouts, inclusions) will be heard, much like a vinyl record.

Could be exactly that, 's just weird that it sounds exactly the same as the vibration noise coming out of each respective player! This sounds exactly like all four players (my three and the Runco) are doing exactly that, "introducing noise of their own" - which sounds exactly the same as the noise they make as the disc spins.

This has me wondering if perhaps VHS would be a better source, but unfortunately it is no simple matter finding VHS copies of THE EXORCIST that predate the switch to the stereo remixes (of which it seems there are at least two, based on my exhaustive collection of THE EXORCIST LaserDiscs... one's almost certainly the Dolby Stereo mix from the theatrical re-release, the other's a plain L+R stereo home video mix). I've only ever found two that might possibly have the mono, and they're absolutely "maybe" rather than "definitely" so I could've bought a couple of turkeys. One's NTSC, one's PAL, both look like 80s tapes rather than the later 90s ones with stereo mixes.

To satisfy my own curiosity somewhat, I'm capturing an early VHS copy of STAR WARS right now to compare it to analogue captures from LDs that I and others have done, and just based on my extremely subjective listening (dropping in every few mins to check on the recording more than anything) I have a feeling it might be a bit better than the analogue LD audio. But I won't know that for sure until I've finished recording and had a proper look at it.

[zoidberg]

For CLV discs the RPM is highest at the start of a side, which is generally when the player is at it's noisiest vibration wise. As the side progresses the the RPM decreases to the point where the player is silent but for the whoosh of air as it spins. If the rumble on the audio is consistent for the duration of the capture then you can probably rule out the player as the source of noise