stereomono

[cdivizia]

Hi,
I have some old italian records from the late sixties with the text "stereomono" written on the record label?

does anyone know what it means? by listening to those records, i would say they are mono but i'm not sure since when converted to wav there are some differences between the two channels, probably due to noise, pop/clicks or bad mastering.

can i safely assume it is mono and mix down the two channels? this would help in reducing noise

or does "stereomono" mean something else?

thanks

[canadiantire]

My understanding of this term is that the record can be played either on stereo or mono turntables.

I conclude that the program has been put to vinyl in mono with two identical programs on each side of the groove walls. I might be wrong in assuming so.

Based on that, I suggest that you confirm the fact that the recording is really mono by doing a listening test using the mono-stereo switch of your preamplifier/amplifier. If you use a pair of headphone, you should be able to easily discriminate mono from stereo.

The analog program can be forced to mono to achieve the noise reduction you want.

It can then be recorded as a standard stereo digital file.


You can also try the following:

The frequency response in the higher frequency is probably not critical.
Try to do the analog to digital transfer at a lower sampling rate (i.e.: 22 or 32 kHz). This will trim most of the surface noise carried in the upper frequency range without having to go through digital noise reduction.

Don't forget to up-sample back to 44.1 kHz to make it compatible to the CD format.

Tell us if it helped.

- Marcus

[cdivizia]

> I conclude that the program has been put to vinyl in mono with two >identical programs on each side of the groove walls.

Thanks canadiantire, this was my opinion as well but just wasn't sure.

I've done the forced mono vs stereo comparison as you suggested and I in most cases would say it's mono although at least a couple of records are clearly stereo - maybe the recording companies wrote "stereomono" on all records to stay on the safe side.

[canadiantire]

There is some subtelty about the "stereomono" statement.

On this side of the ocean, records manufactured in the sixties often had the mention "can be played on mono or stereo equipment".

I remember reading something a while ago about this issue.

If my memory serves me well, there have been some issues with vinyls which had total separation of the instruments/voice on either channel (left and/or right).

Quite a few songs from the Beatles were recorded that way.

During those years, the stereo compatibility was still not if full force (mostly because of the large amount of portable mono players on the market).

Depending on their design, some players would not reproduce the whole musical program contained on the vinyl.

This is where the need for such vinyl compatibility notice came from.

On vinyls that could be played on mono or stereo equipment, the program could either be recorded in mono or the stereo musical/voice program was "distributed" on both channels so that the essence of the song was available on the left or right channel.

The need for such compatibility gradually faded away in the early seventies, so did the compatibility notice.


- Marcus

[Graham_Start]

Originally Posted by canadiantire

If my memory serves me well, there have been some issues with vinyls which had total separation of the instruments/voice on either channel (left and/or right).

Quite a few songs from the Beatles were recorded that way.

Not really deliberately though; their early albums were meant to be heard in mono and multi-tracking was in its infancy. They started off with only 2-track decks, and put the instruments on one, and vocals on the other, so that there would be better separation on mixdown. When it came time to do stereo, all they could do was put each track in its own channel, which of course sounds totally stupid. But they didn't think this stereo gimmick would catch on back then.

This is why when the albums were put on CD, George Martin insisted that the first two albums be issued in mono. The stereo version sound completely silly. Supposedly he was okay with the next two being stereo, but EMI put out the mono ones anyway. Two other albums (Help and Rubber Soul) he remixed for the 1987 CD because the stereo mixes were crap. The original stereo mixes went back to the everything-hard-left-or-hard-right formula for mono compatibility, which I'll explain in a minute. Still, all of their albums up to and including Sgt Pepper were meant for mono, and many Beatles fans are quite dismayed that the mono versions (which had many significant mix differences to the stereo) have not been reissued.

Anyway... the problem with playing stereo records on a mono system is two-fold: First, 180° out-of-phase signals cancel out, but these are rare (and difficult to cut anyway). The second and much more common problem is that anything which is panned in the middle will be boosted compared to anything panned hard left or right when the channels are folded-down. On a typical 60s wide stereo recording, you'd have for example the vocals in the centre, the guitars hard left, and the keyboards on the right. When you fold that down to mono, the vocals become twice as loud as the instruments, and the whole mix is off. This is very evident if you look at some of the youtube clips people have posted where the audio was originally wide stereo, but youtube folds down to mono. Some of them become near-acapellas, like the Petula Clark clip that I found the other day. This is one of the main reasons why back then, they did separate mixes for mono and not just fold-downs. Today it isn't necessary, both because there's very little that is mixed in "wide stereo", and of course mono playback is now the exception and no longer the rule.

[canadiantire]

Originally Posted by Graham_Start

The second and much more common problem is that anything which is panned in the middle will be boosted compared to anything panned hard left or right when the channels are folded-down. On a typical 60s wide stereo recording, you'd have for example the vocals in the centre, the guitars hard left, and the keyboards on the right. When you fold that down to mono, the vocals become twice as loud as the instruments, and the whole mix is off. This is very evident if you look at some of the youtube clips people have posted where the audio was originally wide stereo, but youtube folds down to mono. Some of them become near-acapellas, like the Petula Clark clip that I found the other day. This is one of the main reasons why back then, they did separate mixes for mono and not just fold-downs. Today it isn't necessary, both because there's very little that is mixed in "wide stereo", and of course mono playback is now the exception and no longer the rule.

Very good point!

My curiosity led me to to spot checks on a few records of my collection that I know are mono.

I could not re-create the phase cancellation principle on any of them by forcing stereo-to-mono reproduction.

I think that phase cancellation is observed on recordings where pseudo-stereo is achieved by shifting the phase of one channel in reference to the other (and to a certain degree, this would also apply to any true stereo recording).

Graham, correct me if you think I'm wrong but phase cancellation issue does not apply to "true" mono recordings.

- Marcus

[Graham_Start]

Originally Posted by canadiantire

Graham, correct me if you think I'm wrong but phase cancellation issue does not apply to "true" mono recordings.

Phase cancellation can only happen when you have more than one signal. Since mono is only one channel and thus one signal, phase cancellation would never happen... unless you've hooked it up to an incorrectly wired stereo cartridge.

[cdivizia]

Originally Posted by canadiantire

There is some subtelty about the "stereomono" statement.
On vinyls that could be played on mono or stereo equipment, the program could either be recorded in mono or the stereo musical/voice program was "distributed" on both channels so that the essence of the song was available on the left or right channel.

Originally Posted by Graham_Start

On a typical 60s wide stereo recording, you'd have for example the vocals in the centre, the guitars hard left, and the keyboards on the right.

hi,

on my italian records of the sixties i was actually expecting some "hard" stereo separation as i usually heard on most british records of the time (even if not usually as much as in "please please me", which is really weird as you pointed out)

instead, vocals and most instruments are mainly in the centre, while only some orchestration is slightly on one channel and drum solos are panning from side to side, such as here (i only uploaded a 10 sec sample so i hope this is not a violation of copyright/forum rules):
File-Upload.net - Ihr kostenloser File Hoster!

so, thanks for all your suggestions about different stereo recording techniques which helped me to listen more carefully

[eddie]

Hey Graham!

Good insight.

I was wondering how the stereo recordings on Stax Lps sounded on vinyl in the 1960's. Was it that phony psuedo stereo? I have almost their entire catalog on CD and mostly mono mixes were used even for the reissue of Lps on CD. Stax just reissued one of Otis Redding's albums in both stereo and mono but that's a rare exception in their catalog. Do you think they remixed the stereo versions if it was that psuedo stereo.

Any insight appreciated.