Hello,
I am about to finish a MiniA and a pre amp, both balanced.
Is there a standard for the interconnect cables, ie what goes on the ends of the interconnects is it a male or female, same for the ins and outs on the pre amp and the input on the amp, male or female?
Thanks and happy new year
Mark.
I am about to finish a MiniA and a pre amp, both balanced.
Is there a standard for the interconnect cables, ie what goes on the ends of the interconnects is it a male or female, same for the ins and outs on the pre amp and the input on the amp, male or female?
Thanks and happy new year
Mark.
I always remember by just assuming the 'standard' is bass ackwards. A properly designed system has the output (driver) equipped with a female plug such that inadvertent touching or dropping does not provide any risk. The input (receiver) end is therefore equipped with the male plug, as touching these pins with your finger provides no risk. Even though we are talking a few volts or less, and there is no real personal risk, the principle stands.
Then I reverse that logic and recognize they decided to do just the opposite.
Output = male
Input = female
Then I reverse that logic and recognize they decided to do just the opposite.
Output = male
Input = female
Yeah. Only thing you need to look out for now is the occasional piece of equipment that has pin 2 and 3 swapped.
Also if you are doing DIY then you don't exactly have to follow any rules. You can use a 2 1/4" to XLR cable to have the ins and outs on the same connection if you are operating unbalanced. There are also 4, 5, and 6 pin versions to do the same idea with balanced.
Also if you are doing DIY then you don't exactly have to follow any rules. You can use a 2 1/4" to XLR cable to have the ins and outs on the same connection if you are operating unbalanced. There are also 4, 5, and 6 pin versions to do the same idea with balanced.
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Otari tape recorders are noted for this 'convention'.
It has no effect on the correct operation of the setup, but means you won't maintain 'absolute phase' throughout.
You are quite right. For some reason I was thinking about RETURN & EARTH (1 & 3)
My apologies
Now here is where I get really confused about the different kinds of balanced devices. As I understand it there is differential balanced and there is balanced impedance. I am pretty sure one of my soundcards is differential and the other one is balanced impedance so I should know this but don't. Now if you were to swap 2 and 3 on a balanced send and return with balanced impedance what would happen?
The modern convention is low source impedance > high load impedance.
They are all differential
Just to reiterate:
Male = send
Female = receive
Pin 1 (X)=Ground
Pin 2 (L)=Line
Pin 3 (R)- Return
Not sure they are all differential actually. And not exactly talking about bridging the impedance. It's just that on one of my soundcards which is supposed to be both balanced and unbalanced out I do not see a differential signal on Pin 3. Not sure I exactly see a signal at all on that pin.
Actually it doesn't have to have a differential signal to reject noise. Just identical impedance. From wikipedia And I am pretty sure that in this case the same thing happens - inverted polarity. Since in both cases they are summed using differential amplifiers.
"Despite popular belief, this (differential signals) is not necessary for noise rejection. As long as the impedances are balanced, noise will couple equally into the two wires (and be rejected by a differential amplifier), regardless of the signal that is present on them.[1][2] A simple method of driving a balanced line is to inject the signal into the "hot" wire through a known source impedance, and connect the "cold" wire to ground through an identical impedance. Due to common misconceptions about differential signalling, this is often referred to as a quasi-balanced or impedance-balanced output, though it is, in fact, fully balanced and will reject common-mode interference."
"Despite popular belief, this (differential signals) is not necessary for noise rejection. As long as the impedances are balanced, noise will couple equally into the two wires (and be rejected by a differential amplifier), regardless of the signal that is present on them.[1][2] A simple method of driving a balanced line is to inject the signal into the "hot" wire through a known source impedance, and connect the "cold" wire to ground through an identical impedance. Due to common misconceptions about differential signalling, this is often referred to as a quasi-balanced or impedance-balanced output, though it is, in fact, fully balanced and will reject common-mode interference."
There are many systems for noise rejection and balanced differential is just one. It primarily uses XLR connectors and any piece of professional kit with XLR connectors should use balanced differential. It can be either balanced impedance or low_z_source > high_z_load.
The method of balanced impedance was used by the telephone industry to send signals great distances. It was also adopted by professional studios and broadcasters, but later abandoned in favour of low_z_source > high_z_load. The main reasons were to reduce the dependency on distribution amplifiers, and the availability of low z drivers. In the UK, the BBC was the last bastion of balanced impedance. Ask EC8010 when they changed over.
The method of balanced impedance was used by the telephone industry to send signals great distances. It was also adopted by professional studios and broadcasters, but later abandoned in favour of low_z_source > high_z_load. The main reasons were to reduce the dependency on distribution amplifiers, and the availability of low z drivers. In the UK, the BBC was the last bastion of balanced impedance. Ask EC8010 when they changed over.
See you are talking about something completely different. What you are talking about is ratio of source to load impedance or matching impedance vs bridging impedance.
When I say the impedance must match I am talking about pin 2 and 3's source and load impedances should match - and not that the source should match the load. See in this case as long as you are feeding a differential amplifier then the interference in theory will be inverted and combined canceling it out - no inverted source signal is required only the inverted interference.
When I say the impedance must match I am talking about pin 2 and 3's source and load impedances should match - and not that the source should match the load. See in this case as long as you are feeding a differential amplifier then the interference in theory will be inverted and combined canceling it out - no inverted source signal is required only the inverted interference.
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