S-VHS player noiser than cheap VCR?
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Capture setup: JVC HR-S7900 -> Cypress AVT-8120 -> ATI 600 USB clone -> VirtualDub w/ Huffyuv
After messing around with a cheap GOVideo Dvd Combo unit I've noticed that the JVC has considerably more audio noise. Attached two clips where you can hear the difference. May have to turn up your volume some to really tell but it's enough that it just has me curious. Besides the hiss and slight level difference the Dvd Combo has more high end to it. Is this just the trade off I get for wanting a better source capture quality? I know I can remove to the hiss to some degree with various programs after capture. Would it be a audio sync nightmare to capture JVC and then with the Combo and use the combo audio? Just looking for all my options or a second opinion if it's not as bad as I think Thanks! |
The SVHS audio is 3-4db lower in level than the DVD Combo audio. It doesnt indicate a problem. Tonally both seem very similar. We tend to think louder audio is better but it's just the way humans perceive audio at different levels. Look up "equal loudness curves".
In any case, in capture the aim is to capture everything cleanly without losing signal or adding noise or distortion. Then in our video or audio program we have the luxury of setting the final level of audio to whatever we like. We only try to set final levels at time of capture if we have no other choice downstream, which is not ideal. It's also possible that your DVD combo unit has automatically " peak normalised" the level, pushing it up as high as possible without distortion but we can also do this in our editing program and with more control. |
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Adobe Audition reports the DVD Combo recorded audio is an average of 3.5 dB higher RMS level, but the frequency spectrum is different. The signal is mono, although the recording is two channel stereo. Channels were balanced within a half dB for each recording. The audio sample rate is 96 kHz
The attached image shows the frequency spectrum levels for the two recordings, one above the other. The red line reflects the DVD-COMBO recording and the blue the SVHS capture. The DVD Combo audio levels are higher at lower frequencies but drop to the drop to the SVHS levels at around 4 kHz, and go even lower above around 12 kHz. If this was a linear track audio recording, the difference in higher frequencies (above 3 kHz) might in part be due to slightly different audio head alignments, and audio above 10 kHz is likely more reflective of audio capability of the VCRs since there is little useful linear audio above around 10 kHz. The audio above around 20 kHz reflects noise floor of the system system. Given the outdoor recording environment with its inherent ambient noise, skate wheels, etc, and the unknown of the original recording system it is difficult to tell which better reflects the ground truth. It boils down to which recording do you prefer to work with. Audio editing tools (e.g., Audition, Audacity, etc.) can be used to filter out noise and adjust frequencies and amplitude, and even bleep out unwanted sounds and dialog. Some NLE's include audio editing tools as well. Syncing audio from a different recordings is not difficult if you have the necessary software tools, and if the two recordings are to the same time base; typically not a problem for video recordings. However, sound from an analog tape (e.g., reel-to-reel or cassette) can be more problematic due to slight variations in tape speed accuracy. |
S-VHS sample looks and sounds better to me, I don't know where you get the impression of noise from, Technically the DVD combo sample is more noisier because of the higher gain.
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That said, I don't really hear much of a difference. Slight level/volume difference, but that's it. The DVD combo unit has some nasty dot crawl. |
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I think the extra noise I'm hearing on the S-VHS is right around to 10khz range. It's real obvious to me once I start messing around with an EQ. I may just be more sensitive to that range and it isn't as bad as I think. I uploaded another sample from 3 sources this time. Shot around my room with a camcorder I have then played back on the same camcorder, then same DVD Combo and SVHS as earlier. They all have their own audio quirks and extra noises at certain ranges.
Atleast I now know what range to focus on when trying to clean up audio. Thanks for the input |
You must be too young for the format, Most people who grew up with VHS know that consumer camcorders and VHS linear mono audio are crap to begin with and can be made even worse like the DVDcombo sample, Like they say: You can't make chicken salad out of chicken sh*t.
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The average over the common length of the two clips' audio as reported by Adobe Audition 3.0 . (the portion of one video that was longer than the other clip was ignored.
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I often hear things others do not, even as I've aged (which is unusual). I sometimes consider it a gift. :) |
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In general hearing declines with age. Exposure to loud noises accelerates the process, and in some cases can cause loss of specific frequencies/ranges of frequencies. I have firearms-induced hearing loss; the good news is it gives me an excuse or not hearing what the wife said :congrats:.
FWIW, I've attached a Audition spectral display of the two clips showing the various frequency components intensity over time. The 96 kHs sample rate is over kill given that there is little if any useful sound above perhaps 12 kHz at best. Linear track audio is on a par with AM radio, worse than audio cassettes. But IMO it was a reasonable match for typical 1970's vintage home TVs with 4" speakers. Given the program material use the sound that pleases you the most. It is not like you are trying to capture a well defined musical performance. |
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Unfortunately VCR's are often designed to internally switch off the audio signal when they detect no video recording. This makes it hard even for technicians to test the noise performance of the deck. But you could try playing back a blank unrecorded tape. If that doesnt work and if your SVHS VCR has an "audio dub" function you may be able to record linear audio over the top of an existing video but with no audio signal, meaning the record volume gain is set to zero (if your deck has record level adjustments). That would give a better idea of the SVHS deck's own noise performance on the linear track.. Most people hearing hiss and buzzes on a linear track assume it's on the recording. Yes there will be some tape hiss but there may also be noise from the deck's own internal amplifier and even other hum and other tones feeding into the amplifier. As I've said before, even a dirty audio head can give the impression of more tape hiss, but it's not tape hiss. The dirty head muffles the recording and the VCR's own internally generated noises have no competition. A simple solution is "clean the audio head" and the deck's own internal noise may not be so much of a concern. As Specs Brothers say, playing back audio or video tapes at its best is more than just a matter of pressing the play button... |
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