On a standard three circuit 1/4" phone plug is the tip hot and what color should it be?
When the telephone company invented it red was ring. Now the ring should be black according to AV standards. Tip was left channel in stereo applications. So does that mean the left channel is wired with red?
The XLR is wired pins 1, 3, 2. 2 of course should be hot by todays standard. Everywhere else 1 is ground or shield, 2 is return and 3 is hot.
Now if a manufacturer made pin 3 hot before the XLR standard changed what should they do?
Hi, Simon.
Here, in Europa we were less concerned by this problem of change of the standard, concerning mostly US gear.
Most of the gear has input and output and the signal just cross them. The only thing that matters is that both are 'in phase'. So for those, it is less critical. Don't you agree ?
The problem is real for old mics, tape recorders, and all speakers need to be tested on their boomer anyway.
Well, you asked what should do a studio with a vintage american gear on the old US standard ? Why not do the same thing than with an old car: Bring it up to actual standards.
A requisite for mics when several are used in the same time.
In a way, it is happy that this "absolute phase" question dont make a critical difference for most of the people at home. On an other side, if it was so, i believe fewer records would be concerned.
Your devoted servant,
Tryphon Tournesol
Hi Tryphon,
As Ed was saying, the big difference for XLR wiring was between Japanese and US equipment mostly. I haven't looked at Studer closely so I don't know what standard they followed.
As for outboard gear, the signal is often inverted before it hits the balanced adapters. From that point forward, everything looks okay as the balanced adapters are connected properly. The actual question is, does the circuit invert - or not? Same as home gear.
The other point that Ed made was maybe not stressed enough. Absolutely everything in audio came from ... the telephone companies. Levels, standard wiring - everything. The problems start when people deviate from what was a perfectly good standard. Don't forget that phone companies had to send tiny signals through literally miles of wiring while keeping it intelligible and hum-free as possible. I think they pulled off miracles when you think about their achievements in the 30's and 40's. Amazing stuff. Then, time multiplexed signals (TDM) and modulated signals to get as many channels, or conversations, onto a signal pair of wires. Amazing stuff. Later they digitized the signals long before we had D/A converters, never mind A/D converters. Everything that was cutting edge in audio is old hat in the telephone companies of the world.
That telephone on your desk, be it analog or digital is an amazing piece of technology. IP phones are almost a throwback compared to a digital TDM phone, but it's the "new" thing.
-Chris
As Ed was saying, the big difference for XLR wiring was between Japanese and US equipment mostly. I haven't looked at Studer closely so I don't know what standard they followed.
As for outboard gear, the signal is often inverted before it hits the balanced adapters. From that point forward, everything looks okay as the balanced adapters are connected properly. The actual question is, does the circuit invert - or not? Same as home gear.
The other point that Ed made was maybe not stressed enough. Absolutely everything in audio came from ... the telephone companies. Levels, standard wiring - everything. The problems start when people deviate from what was a perfectly good standard. Don't forget that phone companies had to send tiny signals through literally miles of wiring while keeping it intelligible and hum-free as possible. I think they pulled off miracles when you think about their achievements in the 30's and 40's. Amazing stuff. Then, time multiplexed signals (TDM) and modulated signals to get as many channels, or conversations, onto a signal pair of wires. Amazing stuff. Later they digitized the signals long before we had D/A converters, never mind A/D converters. Everything that was cutting edge in audio is old hat in the telephone companies of the world.
That telephone on your desk, be it analog or digital is an amazing piece of technology. IP phones are almost a throwback compared to a digital TDM phone, but it's the "new" thing.
-Chris
Dear Colleague,
Thanks for your answer.
Studer is a Swiss Company. Swiss do not play with the Standards ;-)
I believe, precisely, that the reason of this change in US was the big success of European Gear (Studer, Neuman etc) and, later, Japanese, in the professional audio world.
I agree, of course, with your words about phone companies. Same story in Europa. I remember my first studies in digital converters, delta-sigma based, a phone's technology already old at this time while it was so new in record industry.
Delta-sigma are the ones I used in my ultrasonic weapon. But I can't tell more:
This weapon could have been too dangerous if it had fallen into the wrong hands and I destroyed the plans.
Your's sincerely,
Tryphon Tournesol
Thanks for your answer.
From Wikipedia: "Prior to the introduction of this standard, the wiring of pins 2 and 3 varied. The pin 2 "hot" and pin 3 "cold" convention was typically used by European and Japanese equipment manufacturers, but American companies used pin 3 "hot" and pin 2 "cold". This caused problems when interconnecting equipment with unbalanced connections. The pin 3 "hot" convention is now obsolete but is still found on vintage equipment."
Studer is a Swiss Company. Swiss do not play with the Standards ;-)
I believe, precisely, that the reason of this change in US was the big success of European Gear (Studer, Neuman etc) and, later, Japanese, in the professional audio world.
I agree, of course, with your words about phone companies. Same story in Europa. I remember my first studies in digital converters, delta-sigma based, a phone's technology already old at this time while it was so new in record industry.
Delta-sigma are the ones I used in my ultrasonic weapon. But I can't tell more:
This weapon could have been too dangerous if it had fallen into the wrong hands and I destroyed the plans.
Your's sincerely,
Tryphon Tournesol
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What is a forum about? Interesting (hopefully) and civil (hopefully) discussions, sharing ideas and helping each other out.
Ask yourself, if you had a question, did you appreciate the answer "go look for yourself" ?
Waly says that often... wont help unless he is paid etc. But no. I was rude. sorry but still holds.
Just adding why polarity is detectable in sound. But type of sound signal will also determine if you can detect it. Thus dblt do nothing useful (IMO) to answer the question of Can You Hear polarity reversal if the optimum sound signal isnt being used for detectability.
THx-RNMarsh
At the same time, you do ask a lot of stream of conscious questions that are straight out of undergrad textbooks/AoE (where they're written much more coherently with surrounding information). I've done it too, but hopefully curtailed that behavior.
I started working as a tech in 1986 (USA). The mantra at every job I have had has always been "Pin 2 Hot".
For the record, I won't help you unless paid, for quite obvious reasons. For more or less different reasons the same applies to a few others, but at least they have the decency not to suggest I should.
I was thinking of making a box to go between my sources and amp, to allow me to invert or not, with make before break relays.
I have some small signal relays with gold over PT Ir contacts that I was planning on configuring two contacts for make before break.
I considered two op-amps, one inverting and one non-inverting to drive the contacts to the output to normalize the effect of the op-amps on the signal (except slew rate will be greater for the non-inverting amp, so that has to be high enough to minimize any slew rate effects).
I haven't settled on the op amps yet, but I was thinking of the NE5534ADR since this is going to be a gain of 1 circuit and they have reasonable specs.
I have some small signal relays with gold over PT Ir contacts that I was planning on configuring two contacts for make before break.
I considered two op-amps, one inverting and one non-inverting to drive the contacts to the output to normalize the effect of the op-amps on the signal (except slew rate will be greater for the non-inverting amp, so that has to be high enough to minimize any slew rate effects).
I haven't settled on the op amps yet, but I was thinking of the NE5534ADR since this is going to be a gain of 1 circuit and they have reasonable specs.
This curve is what I run into in audio ---- Without real world experience, in making successful high-end audio designs, sufficient knowledge is not attained.
THx-RNMarsh
Still in sunny downtown Bangkok.... living large. Last night, wine dinner party at posh restaurant (French chef). But, cant wait to get back and continue progress and working with JC on ultra-PA and preamp.
THx-RNMarsh
Still in sunny downtown Bangkok.... living large. Last night, wine dinner party at posh restaurant (French chef). But, cant wait to get back and continue progress and working with JC on ultra-PA and preamp.
Poking around on my computer, I found this article from 'Audio' magazine that is almost 55 years old and is almost a revelation in insight to the negative feedback problem, yet done so long ago---before Otala, Jung and just about everybody else who has had concerns about the secondary effects of negative feedback. Let's discuss it! Remember, this is before personal computers, almost before computer aided design, and even before silicon transistors became popular. In the early days, graphical techniques were often applied to get a better understanding of an electrical problem and this is an example that, at least to me, is quite revealing.
Kinda depends on who you think the audience is... making the question and answer as simple as possible makes it useful to the broadest audience. Something I learned from a magazine editor long ago. KISS. Just my style now.
You can always go deeper into ever greater detail as an option and as required or needed.
THx-RNMarsh
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