Old music recording remaster process ?

I'm just guessing that the medium used to record albums was better than the one used to sell it (Its the same today).

 

Probably magnetic tapes. I guess the CDs of today can fit in a lot more data than a cassette.

Many studios preserve the original multi-track tapes (1-2 inch magnetic media) that are used to prepare the original masters. When re-mastering, they typically go back to those original recordings and digitally capture them - then re-master the recording using that original, unadulterated source material and newer digital mastering methods.

 

If not those are not available, they'll use the best copies of the available master mixes they can (again, usually 1-2" magnetic tape), digitally capture it, and work from that data to make new masters (often just finding those master tapes that are less worn from being used in multiple vinyl pressings, lets them recover a lot of detail). 

Edited by liamstrain - 10/24/12 at 12:42pm

Yes, typically. But bear in mind those 2" tapes hold a LOT of information.

Edited by liamstrain - 10/24/12 at 12:41pm

The magnetic tape they use is rather different from a cassette tape.

A CD is able to contain all of the audible sound on a 24 track mixdown. I personally prefer CDs for legacy titles. There might theoretically be an advantage with DSD recordings, but I doubt you can hear it at normal volume levels.

A 2 inch tape contains 24 tracks, so the surface area of each track is about the same as 1/4 inch reel to reel which holds four tracks on a 1/4 inch tape. The difference is that a 2 inch master travels at 15 or 30 ips. Consumer reel to reels go 3 3/4 or 7 1/2 ips.
Edited by bigshot - 10/24/12 at 10:05pm

Multi-channel (usually 5.1 or 4.0) doesn't do you any good if you are listening on headphones. It has to get converted to 2 channel at some point.

 

I have a SACD of E Power Biggs playing Bach's The Four Great Toccatas and Fugues on 4 organs (http://www.amazon.com/Bach-Four-Great-Toccatas-Fugues/dp/B00008PX99/ref=cm_cr_pr_product_top) that is considered one of the best multi-channel releases ever. It really doesn't do much for me when played back on headphones. It's just like the SACD you listed and was originally recorded in quadrophonic sound.

Edited by Radioking59 - 10/29/12 at 10:42pm

 

It is possible to simulate multi-channel for headphone listening, by convolving each channel with the HRTF of the corresponding speaker location, Dolby Headphone does this, for example. Of course, not everyone will prefer this to listening to a simple stereo mix.

 

Wouldn't this require computer playback or a special receiver? So unless you have the SACDs ripped with a PS3 or a DSD receiver with Dolby headphone, I don't see how this would work.

Edited by Radioking59 - 10/30/12 at 11:18am

Do multichannel simulators take multichannel input, or do they only create their own ambiences?

 

Pretty much.  Or if you can get a line output for each channel, of course it is possible to process it with the right transformations to get the desired effect (either doing the HRTFs in hardware, or more likely, doing another A/D -> processing in digital -> D/A).

 

 

 

Dolby Headphone can take 5.1 input.

 

There are plenty of surround sound downmix options for headphone (and even stereo speakers) playback, so you can at least use the information in the extra channels in some way when playing back a surround sound source like a movie.  It's been a while, but I tried the ffdshow audio filters stereo -> headphones, and that sounded not so good compared to just playing back the original stereo on headphones, but with a surround sound source the 5.1 -> headphones sounded okay and to me was better than just taking the stereo channels.

 

Conceptually, you're just looking at mapping X inputs (one for each channel source, corresponding to each speaker and its location for a surround sound setup) to Y outputs (one for each speaker or headphone transducer).  There is a transfer function for each input to each output.  At each output, sum the corresponding parts from each input and play that back.  You can use whatever transfer function you want, whatever number of inputs and outputs:  2 inputs to 2 outputs type of crossfeed for converting normal stereo speakers positioning for headphone playback, 5.1 inputs to left/center/right speakers, and so on.  It's just that the "correct" transfer function depends on the input's intended speaker positions and your output speaker/headphone positions (and also your head/ear/torso/etc. shape).

Edited by mikeaj - 10/30/12 at 1:16pm