I want to start a topic I found interesting about speaker terminals on amplifiers back plate made of conductive material and it's influence on sound.
This findings started not long ago and is from another place so some of it may lost in translation.
Topic starter mentioned that he have been long interested in "slit" between amplifier output terminals on a back plate of various amplifiers.
For example when installing cable lines it is forbidden to lay phase wires in separate pipes for each conductor or lead them into electrical board through separate holes.
Phases (Phase, Live) and Neutral must always pass through one hole otherwise at high currents everything starts to heat up.
Ofcaurse there is no such currents in home amplifiers but music is a subtle matter..
After some seaching through internet he found that WBT do milling in their aluminum mounting plates where there are either large oval hole for plastic frame or cutout line betwen terminals.
He also google "Marantz back plate" pictures, they also do it for a long time.
The point is that "+" and "-" pass through the same hole in the metal plate.
So he start experiment and сarefully cut a line between his speaker terminals on his amp back plate.
Result of experiment was change in sound on upper middle and high frequencies on a higher volumes. Sound is more clean and with more air.
He proposed to try this experiment for a start just by open amp cover and connect to speakers bypassing the holes in the rear panel of the case and hear results.
Another member mention that this way excluded short-circuited loop of "air" transformer.
And athough the coupling coefficient is small
a) With an increase in the line current, losses on the current induced in this loop become noticeable.
b) With an increase in the frequency, the losses increase even more.
That is, at high frequencies the amplifier operates not only for the load in the form of the impedance of the speaker system + speaker cable, but also for losses in the "quasi-transformer", which to a certain extent increases distortion.
The effect is more pronounced in transistor amplifiers with low output impedance.
This member also remebered that he had somewhere some interesting spectrograms of the same amplifier board (self made amplifier).
One of which is just on the table in the form of a breadboard, and the second is an amplifier already assembled in the case with terminals on a metal panel.
In the second spectrum a slight increase in higher harmonics is clearly visible.
So I hope more smart people will chime in and topic evolve in interesting findings.
Or say that this effect insignificant and be done wit it. 🙂
This findings started not long ago and is from another place so some of it may lost in translation.
Topic starter mentioned that he have been long interested in "slit" between amplifier output terminals on a back plate of various amplifiers.
For example when installing cable lines it is forbidden to lay phase wires in separate pipes for each conductor or lead them into electrical board through separate holes.
Phases (Phase, Live) and Neutral must always pass through one hole otherwise at high currents everything starts to heat up.
Ofcaurse there is no such currents in home amplifiers but music is a subtle matter..
After some seaching through internet he found that WBT do milling in their aluminum mounting plates where there are either large oval hole for plastic frame or cutout line betwen terminals.
He also google "Marantz back plate" pictures, they also do it for a long time.
The point is that "+" and "-" pass through the same hole in the metal plate.
So he start experiment and сarefully cut a line between his speaker terminals on his amp back plate.
Result of experiment was change in sound on upper middle and high frequencies on a higher volumes. Sound is more clean and with more air.
He proposed to try this experiment for a start just by open amp cover and connect to speakers bypassing the holes in the rear panel of the case and hear results.
Another member mention that this way excluded short-circuited loop of "air" transformer.
And athough the coupling coefficient is small
a) With an increase in the line current, losses on the current induced in this loop become noticeable.
b) With an increase in the frequency, the losses increase even more.
That is, at high frequencies the amplifier operates not only for the load in the form of the impedance of the speaker system + speaker cable, but also for losses in the "quasi-transformer", which to a certain extent increases distortion.
The effect is more pronounced in transistor amplifiers with low output impedance.
This member also remebered that he had somewhere some interesting spectrograms of the same amplifier board (self made amplifier).
One of which is just on the table in the form of a breadboard, and the second is an amplifier already assembled in the case with terminals on a metal panel.
In the second spectrum a slight increase in higher harmonics is clearly visible.
So I hope more smart people will chime in and topic evolve in interesting findings.
Or say that this effect insignificant and be done wit it. 🙂
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Neutrik speakON?
He also said about them too "IMHO - the most successful decision, if you do not take into account the "religious" dogmas ....". 😀
Yep Speakon, but get the STX version.
The STX has solder cups.
In my experience it's the best speaker connection I have ever used. It's also not ridiculously expensive.
That and Canare Star Quad cable.
The STX has solder cups.
In my experience it's the best speaker connection I have ever used. It's also not ridiculously expensive.
That and Canare Star Quad cable.
Actually the best speaker binding post on the planet would be a cable gland.
No binding post at all.
It's even the cheapest solution.
Obviously it's going to be somewhat sensible to at least have a traditional binding post probably mounted at the speaker end but if it's going through wood - no problem. Or use some of the suggested parts above if mounted a metal panel.
No binding post at all.
It's even the cheapest solution.
Obviously it's going to be somewhat sensible to at least have a traditional binding post probably mounted at the speaker end but if it's going through wood - no problem. Or use some of the suggested parts above if mounted a metal panel.
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If you consider the output impedance of most amps is extremely low (transistor amps) then a loop of metal around the connector is going to make virtually zero difference.
Virtually is not going to help people sleep at night.
Hahahaha
I agree.
Though once people know about something like this, regardless how infintessimaly insignificant it might be, it's gonna cause a brain aneurysm for a lot of people.
Hahahaha
I agree.
Though once people know about something like this, regardless how infintessimaly insignificant it might be, it's gonna cause a brain aneurysm for a lot of people.
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Any suggestions for sturdy LS chassis connectors? Connectors like in post 8 are quite fragile with the little plastic tag used as rotation lock. Speakon is not that universal, and not used in consumer amps. The in post 1 twin connector in plastic, seems to be more robust against excessive rotation force. But did not find a source of this kind of connector.
I'm in the same search for good speaker connectors... I hate connectors... too bulky or to delicate, far too expensive or they are just made of crap metal with useless -you can almost whipe off- goldflash over nickle anyway. Some old stuff I have has some higher degree of copper in them, but all new stuff uses light yellowish low copper content alloy underneath when you cut it a bit (on solderside). Currently I use decent industrial types, just nickle.. no gold finish. I'm very tempted by the tellurium copper ones from Meuler or Ponoma (I believe these are the same rebranded parts, but problem with them is that the clamping hole is a bit small. I don't use banana plugs all the time and like to clamp my cables.
BU-P3770-0 Mueller Electric | Mouser
3770-0 Pomona Electronics | Mouser
BU-P3770-0 Mueller Electric | Mouser
3770-0 Pomona Electronics | Mouser
After some google searches, I found this on the web:: "I've used Pomona 3770 gold plated Tellurium Copper posts with good results for a while, however recently I've ordered a somewhat cheaper "Mueller" posts from Digikey, and found these to be a Chinese copy of Pomona ones, of inferior quality (cracks in the plastic, not as accurate shape) and - most important difference - Pomona posts are gold plated over copper directly, but Mueller ones have a Nickel layer as well (and still the gold layer peels off easily). Pomona posts cost only about 30% more."
I thought that plastic "tooth" may break if terminals tighten with a strength of a titan. ) But never heard complains before.
Plastic frame (WBT-0718) as I understand have 3 versions for all of WBT pole terminals and also their RCA sockets.
It is actualy made of polyamid + synthetic rubber with purpose to dampen vibrations.
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Just have two wires coming out the back ( of speaker ), twist each one together with the speaker cable, then stick in a terminal block and tighten up the screws - the terminal block will keep the wires separate to prevent shorting, and stops them untwisting. A work colleague joined two lengths of speaker cable together and had no problems with tarnishing ( for about 20 years, until the foams went on his Heybrook hb1s ), although there was a LOT of tape over the joint. Perhaps silver conducting paint would help? Aren't conductive rings lowered over transformers to control output? I think this was done in electric locomotives . If the wires went through a ferrous metal plate there should be and increase in inductance, but very small.
Polyamide ie mostly like nylon is a very tough durable material.
You can deform it - it tends to fail in a ductile manner, not due to cracking, it's not a brittle material.
I was writing about that (WBT-0718) frame, but WBT terminals washer with a "tooth" is also made of polyamide (PA) 6 (10% glass fibre). Well yes this is also type of nylon. I guess it is more durable for anti twist purpose than plastic washer.