VCR one up on DVR?

I don't think there's any easy way to do that on ANY unit. The way the video's encoded, it'd be a 2-3 step process on a PC to strip the audio and replace it with something different (or you'd use a video editing tool that could do timelines, audio tracks, etc, but it'd be unwieldy to set that up in a DVDR UI)... I could be wrong but I don't think I've heard of that on any unit.

A VHS tape is relatively easy, since the video and audio tracks are separate it can just re-record one without disturbing the other. MPEG video needs to be yanked apart and then reencoded.

Just hook up the camcorder with the yellow video cable and the audio from your boombox. Press play on both when you start transferring to HDD. You could prob. even record boombox on right audio and camcorder sound on the Left audio for a special "Urlee Production"...you can play with the TV's Balance control during playback if sound levels don't turn out perfectly, e.g., music too loud?

I was under the impression that it was an issue of adding new sound AFTER it was recorded. If you have your new music source ready to go at the time of transfer to the HDD, then yeah, that method works.

Uh, I could be wrong, but that 1983 vintage portable recorder can do sound on sound via the VHS linear tracks which is low fidelity at best (even lower if you use the "stereo" mode since that further reduces bandwidth). Since you are "mixing" audio I suspect you are using two mono tracks (once again very low fidelity). This is a niche feature on an older "porta cam" recording unit (i.e., the camera was separate) and is not typical of consumer grade VCRs. Futhermore, hi-fi stereo vcrs which started commonly appearing a few years later recorded hi-fi stereo audio "intermixed" with the video signal, so hi fidelity audio on audio was not possible w/o dubbing (because you would have to corrupt the video - though low fi audio could still be recorded on the linear track and "mixed" with the hi-fi audio). In any event, the results generally were disappointing. I will take high fidelity dolby digital 2.0 audio on today's DVD R's over primitive audio on audio VHS tricks anytime. Also, I would hardly call this a common VHS VCR "advantage" feature vs. DVD recorders because it was not commonly provided on consumer grade VCRs. Audio on audio mixing and other advanced editing techniques such as transitions and overlay titles are best done on a computer vs. standalone DVD recorders or VCRs in any event.

Urlee curious how was the audio quality on the VPJ900 - Was it linear audio, was it stereo? I was making assumptions based on my recollection of what was possible with 1983 vintage VCR gear and would like hear whether the quality was actually better than what I suspect.

I'll confirm most of what vferrari says. Adding audio went on the linear tracks only, even in my very expensive consumer SVHS editing decks, one Sony, one Mitsubishi. My only dissent from what he says is that I did also have two mid-level decks which could add linear audio, a Philips and a Quasar, both VHS. My high end editing decks would let me do "insert editing." Thus, using another deck as a source, with the same video on it, but a different audio source, it would have been possible to put in a different audio on the same video. But of course you could use this same procedure with a DVDR, and a DVD player, plus a different audio source.

Yes, what earlier posters have said confirms my experience with an SVHS edit vcr; I could ADD a linear track, but it would not alter the original audio, airplane flying overhead, other loud noises, etc; useless. As I recall, I don't think the linear track would copy.

The only solution I found was a pair of Hi-8 EV-S7000 Edit vcr's. I could add a separate PCM audio at a different location on the tape. What made it usable was that on playback I could select the original only, mix both, or just the new.

I also find a simple Stereo Audio Mixer from Radio Shack very useful for merging or adjusting audio levels for tapes from various and sundry sources.