Studers and Absolute Polarity

[LInks]

This may be considered too esoteric a topic for this forum,
however, someone out there may know the answer.
My 2 Revox Pr99s are correct polarity on playback.
What do I mean?
A positive going pulse on the tape produces a positive going
output from the electronics via XLR or the DIN output.
When recording via the XLR line inputs the output polarity is reversed
and the positive pulse is now a negative one on output from tape.
( I have a couple of XLR adapters with reversed polarity on order to
address this issue when recording.)
How am I testing this?
A Galaxy Audio "Cricket" Polarity test set.
Remember I am not talking about phase here.

I would like to know if Absolute Polarity was even considered in Studer's
past professional product line.
I have a number of tapes recorded with a variety of Studer machines
from my years at the CBC.

Just looking for some info, not interested in discussing the merits of the
audibility of Absolute Polarity.

If interested, I started a discussion on Absoute Polarity at SA-CD.net

http://www.sa-cd.net/showthread.php?page=1

 

[RogerD]

Here's some information....I think this is what you want...fwiw.


http://home.comcast.net/~mrltapes/pub203.pdf

 

[LInks]

Thanks, an interesting read.
"Surveys of industry usage have shown that professional magnetic recorders had been about half one way,
and half the other, but the majority are now according to the standards."

Just wonder which half Studer was in the late 70s early 80s.

 

[jdza]

Studer was very conscious of how they wired their machines.The service manual on each of the models have the wiring standard clearly marked. Problems arose in that European and American convention often differed . On models like the early 70s B62 and A80s there would actually be a page in the manual showing two different configurations for the different markets.

It is also possible that big clients all had their own standard and machines were wired for that client.

A polarity tape is nevertheless invaluable. When I initially installed Mark Levinson cards into my A80 (a slide in action) the 2 channels were out of phase to each other.This had to be rectified at the heads as the ML5 is not a balanced design.I also have an Ampex 440C that a former radio host used to try and realise his dreams of becoming a famous singer. His demo tapes was made on this machine. Some cruel tech must have disliked the guy as the 2 channels were wired out of phase to each other on the recording side. That must have made centre panned voices sound very weak. Sadly his singing career never took off.

 

[Listens2tubes]

Found a good writeup on absolute polarity.

 

[astrotoy]

In my ripping project, I have spent a fair amount of effort in determining absolute polarity of recordings. For classical recordings, I have found that most recording labels (like Decca, EMI, RCA) are consistently reversed in polarity. With horn speakers it is easier for me to hear the correct absolute polarity, although this is not always the case. For popular recordings and many multimiked classical recordings, it is much more difficult or impossible to determine absolute polarity. I believe this is because as is mentioned in one of the articles, that mikes were often wired with different polarities, so the recording itself is a combination of positive and negative polarities. Also, I have heard that many multidriver speakers have different drivers wired with different polarities, so again it is very difficult or impossible to hear absolute polarity.

Fortunately, there are now a fair number of preamps that have an absolute polarity switch, so you can test the recording yourself.

Larry

 

[NorthStar]

I wonder how many audiophiles on Earth are listening to their music recordings with absolute polarity (in-phase, all the way; inside in & out)?

 

[Bruce B]

I wonder how many audiophiles on Earth are listening to their music recordings with absolute polarity (in-phase, all the way; inside in & out)?

Bob.... Polarity and Phase are 2 different things.

 

[NorthStar]

Bob.... Polarity and Phase are 2 different things.

Polarity = + and/or - (plus & minus).
And phase?

Do many people use the terms to mean the same, Bruce? ..Like by inverting the polarity (speakers for example) you actually invert their phase?

 

[Bruce B]

Polarity = + and/or - (plus & minus).
And phase?

Do many people use the terms to mean the same, Bruce?

That's correct.... Polarity is +/-. Is the waveform going up + or down -. That is Polarity. So if the L/R waveforms are going up, like a snare hit, when they are supposed to go down, then that is reversed Polarity.

Phase is the relationship between the Left and Right channel. Are both waveforms going up? If not, if the left channel waveform is going up and the right channel waveform is going down, then it's not in Phase.

 

[NorthStar]

That's correct.... Polarity is +/-. Is the waveform going up + or down -. That is Polarity. So if the L/R waveforms are going up, like a snare hit, when they are supposed to go down, then that is reversed Polarity.

Phase is the relationship between the Left and Right channel. Are both waveforms going up? If not, if the left channel waveform is going up and the right channel waveform is going down, then it's not in Phase.

That's right; thanks for that. ...It escaped me for a second.

* A mono recording is then always in-phase?