Cereal Killer
432
Out of curiosity does anyone know why on the Mogami 3104 and 2972, 1-3 & 2-4 configuration changes the cables capacitance and doesn't affect inductance?
Mogami Speaker Cables
- Thread starter Cereal Killer
- Start date
rn82497
pfm Member
Interesting. I'm using 2972 in a Rega Isis / Osiris & Shahinian Obelisk setup - and I wouldn't recognise that description; rather musical & transparent & neutral. DO people find 3103 significantly different to 2972?
Jonathan
pfm Member
Cereal Killer
432
This is the only thing i could find and it refers to a 50hz noise rejection: https://www.belden.com/blog/broadcast/how-starquad-works
Cereal Killer
432
Not having tried the 2972 i couldn't say but from looking at the data sheet there's miniscule differences in the capacitance, which would change more if the cables were a couple of metres longer. So my theoretical conclusion would be no.
Cereal Killer
432
Thought I'd revisit the experiment as i had an extra set (8) of Hicon banana plugs left...
Just made some Mogami 3104 2-2 speaker cables @2.5m each in the 1-3 (starquad) configuration, not an easy task to make them neatly and professionally, it's 4x4mm2 (8mm) into the back of a banana plugs is tricky... however a perfect excuse to try out the new soldering iron.
Liking them alot...
Just made some Mogami 3104 2-2 speaker cables @2.5m each in the 1-3 (starquad) configuration, not an easy task to make them neatly and professionally, it's 4x4mm2 (8mm) into the back of a banana plugs is tricky... however a perfect excuse to try out the new soldering iron.
Liking them alot...
lazycat
pfm Member
While you're at it, make a USB cable.
Cereal Killer
432
LOL - if you'd taken the time to read the threads you'd have seen i use a 1m Lindy CROMO USB A-mini-B. Its £7, couldn't make one cheaper ;-)
Cereal Killer
432
I use 3104 (had 3103 before). I use brown and orange together and red and yellow together. Don't remember how i corresponds to the above explanation.That's on the amplifier end (quite a hassle to find room for all the wire) as I bi-wire the 4 ends at the speaker end - perhaps defeating the intention?
Not easy at all... took me 2 hours to get this result
Cereal Killer
432
Think there really is some true science behind this: https://www.belden.com/blog/broadcast/how-starquad-works
If you've read the last few blogs, you'll know we've been discussing balanced lines, differential signals, and common-mode noise rejection. But one of the key factors we really haven't discussed is the cable itself.
In the last blog, we talked about how electromagnetic noise signals, called common mode noise, hits both wires in our twisted pair and cancels out. But, to be truthful, the noise is cancelled out only if the two signals are identical. The closer to identical they are, the greater the rejection or common mode rejection ratio, CMRR will be.
We have a saying in cable manufacturing: physicals equal electricals. What this means is that the two wires need to be physically identical if we want the noise signals to also be identical, and the noise rejection to be 100%.
Well, aren't the two wires in a twisted pair 'automatically' identical? After all, we twist those wires together. Isn't that enough? Sure, twisting helps a lot, but it doesn't make the two wires identical. Those two wires should also be the same AWG (gauge) size.
Education or lack of education about the effect of perfect manufacturing process can make all the difference in the ultimate performance of a twisted pair: understanding the importance of calibrating the machines for drawing from bigger wires to smaller wires and for precisely twisting them around each other with the same tension, etc.
If one was a lot tighter with a higher tension on the conductor than the other, then you would be winding one wire around a second straight wire. They wouldn't even be the same length, much less the same resistance. This alone would affect the noise rejection. If the length or wire size is different then one noise signal will be greater than the other and they won't cancel out. If one wire is longer than the other, the noise signal on one wire will arrive earlier than the other. They will be out of phase and again will not cancel out.
But let's say we solved those problems and used two wires of exactly the same size or AWG, the same length and that are twisted with the same tension. There would still be one thing left to compromise our noise rejection: the two wires of the twisted pair are not in the same place.
Think about it. The electromagnetic noise hits one wire and then it hits the other wire. It might be a picosecond later, but that means they do not have identical signals and the noise rejection will not be 100%. Again the signals will be out of phase.
And this is one reason we use Bonded-Pairs, pairs where the two wires are stuck together, without glue! Many of our Category data cables use Bonded-Pairs and now you understand why: no matter how you flex or bend the cable you will still get maximum noise rejection. There are other reasons to bond the two wires which we might talk about in later blogs.
We are beginning now to make Bonded-Pair audio cables. Belden 1353A is the first of these. It's intended for analog or digital audio and features a single bonded twisted pair. This makes it the lowest noise pick-up with the highest CMRR of any audio cable. However, it is not shielded. Since the majority of noise rejection in a twisted pair is because it is a balanced line, the noise rejection of 1353A is excellent, in many applications superior to a shielded cable.
If you need a shield to do something other than shield, such as Phantom Power, where the shield is part of the power delivery to the microphone, well, Belden 1353A won't work there. But, even in a Bonded-Pair, the two wires are not in the same place, the ideal for maximum noise rejection.
Of course, you're going to say that two wires insulated from each other cannot possible be in the same place, right? Wrong! And the way to get two wires in the same place is to start with four wires spiraled together, as shown in the image below.
If you combine the wires across from each other, you end up with a pair.
But look at that first picture of the inside of the cable and think about the electromagnetic noise. By combining the wires, you really do have the two conductors inside each other. Even if you don't believe it, the proof is in what this amazing design can do. For instance, one of the worst noise offenders is 60 Hz power (50 Hz for much of the world).
There is no shield of any kind that we can apply to a cable that has any effect on that low frequency. Even a solid steel conduit, perfectly installed, is only around 30 dB of noise rejection at 60 Hz. But starquad cable is up to 50 dB noise rejection at 60 Hz.
If I were running mic lines near power cables, I definitely would think about starquad! If I was hanging audience microphone from a lighting grid, I definitely would think about starquad.
Belden makes three sizes: Belden 1192A, full size, Belden 1172A small size, and Belden 1804A miniature. The full size is standard mic cable size. The smaller one is excellent for wiring mic booms, or places with restricted space. The miniature is like lavaliere cable.
Since users might be scared of such a small cable, it is made with a special alloy making it super-strong. The conductors in the miniature version are silver-plated to bring the resistance back up to the same value as if it was bare copper. We'd be happy to send you a short sample of any of these. 1-800-235-3361 (1-800-BELDEN-1)
If you've read the last few blogs, you'll know we've been discussing balanced lines, differential signals, and common-mode noise rejection. But one of the key factors we really haven't discussed is the cable itself.
In the last blog, we talked about how electromagnetic noise signals, called common mode noise, hits both wires in our twisted pair and cancels out. But, to be truthful, the noise is cancelled out only if the two signals are identical. The closer to identical they are, the greater the rejection or common mode rejection ratio, CMRR will be.
We have a saying in cable manufacturing: physicals equal electricals. What this means is that the two wires need to be physically identical if we want the noise signals to also be identical, and the noise rejection to be 100%.
Well, aren't the two wires in a twisted pair 'automatically' identical? After all, we twist those wires together. Isn't that enough? Sure, twisting helps a lot, but it doesn't make the two wires identical. Those two wires should also be the same AWG (gauge) size.
Education or lack of education about the effect of perfect manufacturing process can make all the difference in the ultimate performance of a twisted pair: understanding the importance of calibrating the machines for drawing from bigger wires to smaller wires and for precisely twisting them around each other with the same tension, etc.
If one was a lot tighter with a higher tension on the conductor than the other, then you would be winding one wire around a second straight wire. They wouldn't even be the same length, much less the same resistance. This alone would affect the noise rejection. If the length or wire size is different then one noise signal will be greater than the other and they won't cancel out. If one wire is longer than the other, the noise signal on one wire will arrive earlier than the other. They will be out of phase and again will not cancel out.
But let's say we solved those problems and used two wires of exactly the same size or AWG, the same length and that are twisted with the same tension. There would still be one thing left to compromise our noise rejection: the two wires of the twisted pair are not in the same place.
Think about it. The electromagnetic noise hits one wire and then it hits the other wire. It might be a picosecond later, but that means they do not have identical signals and the noise rejection will not be 100%. Again the signals will be out of phase.
And this is one reason we use Bonded-Pairs, pairs where the two wires are stuck together, without glue! Many of our Category data cables use Bonded-Pairs and now you understand why: no matter how you flex or bend the cable you will still get maximum noise rejection. There are other reasons to bond the two wires which we might talk about in later blogs.
We are beginning now to make Bonded-Pair audio cables. Belden 1353A is the first of these. It's intended for analog or digital audio and features a single bonded twisted pair. This makes it the lowest noise pick-up with the highest CMRR of any audio cable. However, it is not shielded. Since the majority of noise rejection in a twisted pair is because it is a balanced line, the noise rejection of 1353A is excellent, in many applications superior to a shielded cable.
If you need a shield to do something other than shield, such as Phantom Power, where the shield is part of the power delivery to the microphone, well, Belden 1353A won't work there. But, even in a Bonded-Pair, the two wires are not in the same place, the ideal for maximum noise rejection.
Of course, you're going to say that two wires insulated from each other cannot possible be in the same place, right? Wrong! And the way to get two wires in the same place is to start with four wires spiraled together, as shown in the image below.
If you combine the wires across from each other, you end up with a pair.
But look at that first picture of the inside of the cable and think about the electromagnetic noise. By combining the wires, you really do have the two conductors inside each other. Even if you don't believe it, the proof is in what this amazing design can do. For instance, one of the worst noise offenders is 60 Hz power (50 Hz for much of the world).
There is no shield of any kind that we can apply to a cable that has any effect on that low frequency. Even a solid steel conduit, perfectly installed, is only around 30 dB of noise rejection at 60 Hz. But starquad cable is up to 50 dB noise rejection at 60 Hz.
If I were running mic lines near power cables, I definitely would think about starquad! If I was hanging audience microphone from a lighting grid, I definitely would think about starquad.
Belden makes three sizes: Belden 1192A, full size, Belden 1172A small size, and Belden 1804A miniature. The full size is standard mic cable size. The smaller one is excellent for wiring mic booms, or places with restricted space. The miniature is like lavaliere cable.
Since users might be scared of such a small cable, it is made with a special alloy making it super-strong. The conductors in the miniature version are silver-plated to bring the resistance back up to the same value as if it was bare copper. We'd be happy to send you a short sample of any of these. 1-800-235-3361 (1-800-BELDEN-1)
ABCaudio
Trade: ABCaudio, representing EWA
While LS-25 is very specific to terminate, it isn't ever £200. We would do it for free to support an existing user who had paid out for the cable, just cover the postage!
We are the only authorised stockists of LS-25.
Cereal Killer
432
Bit late in the day, they've been sold to a very happy customer.
Cereal Killer
432
Just terminated the 3104 again with these (spades). They are 8mm (upto 16mm) cable entry. I tinned twisted pairs (1-3) then crimped/closed the cable entry (with a protool) them soldered them on. A very neat pro finish for £25!
https://www.ebay.co.uk/itm/HICON-HI-CTA01-Speaker-Connector-Spades-Lugs-1pcs-max-16mm/281842365105?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649
This site contains affiliate links for which pink fish media may be compensated.
Paul Burke
pfm Member
Hi CK, what tools are you using crimps wise etc? Just about to do a set myself, not Mogami but quite a big cable. Will be getting some decent spades for it like those
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Cereal Killer
432
Evening Paul, this tool pick your suitable die: http://rover.ebay.com/rover/1/710-5...0001&campid=5338728743&icep_item=401606412561
This site contains affiliate links for which pink fish media may be compensated.