AF to do Simon & Garfunkel's Parsley, Sage, Rosemary, and Thyme

This is meant as irony, right? Or is it simply a pompous attempt to derail a thread?

 

This is especially so if they 80's Columbia CD was indeed sourced from a transfer of a copy of the master tape. If the AF is indeed from the original found in the vault, then to sync up so perfectly, both tape machines used would have to be playing back at exactly the same speed plus the two tape machines used to play back the original master when the copy tape used as a source in the 80's was first made would also have to play back at the same speed.

That's four tape machines all playing back at exactly the same speed with two different tapes and zero shrinkage, stretching, etc., in a period of over 20 years!

 

In other words, vurtually impossible, right?

 

BINGO

 

It would seem so. Then again Pink Floyd, Led Zeppelin and the Eagles all did reunite at one time or another and a pig did fly over Battersea (sorta).

 

Why shouldn't they synch up...they're the same songs!

 

Kevin's e-mail message was ambiguous. At this point, I don't think it would mean a hill of beans if he came back and claimed that he used the original master tapes. Many people here have made up their minds that he did not, and based on the available data, I cannot blame them.

 

Tapes stretch, playback motors depend on electrical frequency, there are lots of factors that could cause a variation that over several minutes could result in loss of synch greater than the 0.003-inch/second covered by one 44.1kHz sample (quick calculation assuming 15ips tape).

 

Thanks to you both, for explaining this to me. I assume this is acetate tape, which I assume does not stretch, as polyester does. As my background is video, I can say we would routinely do live switching using two or three video machines, all started manually (I was adept as an intern due to having long arms - I could reach and start two machines on cue). These machines would stay in sync for the program's hour-long duration. This was all pre-digital.

 

I was being facetious in referencing Kevin's response.

 

But then again you were using SMPTE.

 

Has anyone else done the 80s cd and AF test yet?

 

I believe it would be because rather than in spite of. One good example I can think of to illustrate this point is Genesis The Lamb Lies Down On Broadway. According to a fan/audiophile friend of mine the Japanese 1st pressing on CD beats all Vinyl pressings he has heard and all other CD pressings.

When the industry started changing to using DAW's that's when sound quality initially went down for me. It seemed to take over a decade until engineers became educated with the new digital world after experimenting with ye olde Compressomatic™ work stations to bring back the SQ. [The previous is based on if the producer and/or the label were not forcing the mastering engineer to make them "louder".] Even still, I think the older CD's usually sound better with some small audiophile label exceptions.

 

You mean they shrink? I don't know how you guys live with those things.

 

We had two IVC-9000 2-inch tape machines and an RCA Quad 2-inch machine. They had time code.

Do audio recorders from that time have such drift? My filmmaker dad had a couple of audio recorders (Uher and Sony) known for their ability to stay in sync with his film camera. Again, I have no idea if this is really relevant, but I can't help but wonder what two waveforms really show, and a lot seems to rest upon the impossibility of sync, hence my inquiry.

 

Was it a Nagra? Those decks write sync code as well.

 

Sorry, I added the brands in after I first posted. Uher and Sony TC-800B, if memory serves.

Part of my amazement is that audio tape machines would have such loose tolerances, Consider that in video/film, we just can't deal with drift.

 

They used sync pulses back then. Look on the track sheets for the Let It Be movie. They reserved one audio track for sync tones.

Also, remember video and film run at 24 or 30 frames per second in the US. CD audio runs at 44,100 samples per second. The possibility of every single one of those 44,100 samples to line up perfectly is an impossibility.

Try this, play a song from CD (through the analog outputs) and recorded it to a CD recorder. The newly recorded CD samples would not be in perfect sync the original CD. I've done it. Instead of phase cancelation you get comb filtering and a really long flanging sound. Really trippy!

 

Yes, I do recall that sound, mostly from his earliest experiments using Bell and Howell's Film-O-Sound, a cassette/Super 8 film sound recording method. It made the sound similar to the vocals on Notorious Byrd Brothers.

Do large analog tape decks from the 60s really drift that much, Jamie?

 

Kevin Gray's point (or the one quoted here anyway) stands, a spectral analysis comparing the two CDs would give a definitive answer. Something like the free software program Tau would handle the debate:

http://true-audio.com/

 

Ronnie Milsap (remember him) has perfect pitch. He used to hate recording to analog tape because he could hear the pitch change from the beginning of the reel to the end. So yes, they do drift.

Even if you get the speed so that 1kHz tone is playback is right on 1kHz it's not 1.000000000kHz. It's more like 1.01kHz. That's more than enough of a difference to hear when doing null tests. The two songs will flange due to timing inconsistencies.

And at the end of the reel the 1k tone will be different than it was at the beginning of the reel even on the same machine.

 

This is a time issue, not frequency. I can hear EQ differences in the two CDs so a spectral analysis would show them to be different.

BTW, I EQ'd the Columbia CD to make it sound like the AF and got another couple dB of cancelation.

 

Thank you. That helps me understand the significance of the waveforms.