Hook-up Wires

[Bombacaototal]

I have been curious if/how much hook up wires will influence the final sound of an amp. This was triggered by a comment from Alessandro High-End Products about using a solid audio grade wire on a build and the result was a more dynamic, fast in response and transparent amp.

To name a few different types:
Fender Style pushback cloth solid core 600V wire
PVC solid core 1000V 1.8A
PVC 1000V 3A
PTFE 1000V 14A

What has been the experience of folks here regarding the sonic differences of the wires?

I am usually using Teflon because they are light and durable, as opposed to the old fender ones which are easy to break the core for example.

[labb]

"Fischer also used solid core wiring because he believed that braided wires create phasing issues between the input and output signals of the amp." And then there is the color of the outer jacket that one must also consider.

[R.G.]

Sigh. It just never goes away, does it?

The answer is maybe - under super-special conditions that would have to be contrived especially to try to MAKE them make a difference. But any differences are so ridiculously tiny that moving a mid-air wire an eight of an inch with a pencil would vastly overshadow any differences in hookup wire.

The folks that try to sell "high end" equipment fall all over themselves trying to explain how very, very special their products are, including using super special wire, metal, paint, part selection, conditioning (cryogenically treated tubes was one of my favorites), and anything else that's rare, hard to find, hard to do, or otherwise induces the aroma of "special".

What has proven very elusive in the "high end audio" world and is moving down into the guitar amp world is actually demonstrating that the super/hyper parts and processes make any audible differences. In the hifi tweako world, a few fair double blind tests of "Golden Ears" folks embarassed the GE's so badly that no one in "high end audio" will do fair tests any more, throwing excuses about the process of testing washing out differences that would otherwise be obvious.

I'm restraining myself, obviously. So my opinion is this: choose your hookup wire on the basis of your needs doing the hookup, and ignore the siren songs of oxygen-free cryogenically treated silver-iridium wire encased in vintage insulation spun from spider silk in the 13th century.

[labb]

What R.G. said.....

[sluckey]

And then there is the color of the outer jacket that one must also consider.

Is clear a color? I've found it to have a very transparent sound.

[pompeiisneaks]

I've always felt white cover makes the sound a bit clouded up, and brown makes it muddy

~Phil

[Mark]

The colour thing came when red wire was used in the Komet amp. I have heard people say there is a difference between Teflon and PVC. Personally, I can't say I've heard any difference. Perhaps the thickness of the insulator might make a difference if the wire was running along the chassis for a decent run.

I did hear from a good source that Fischer used solid core as it was easily available. Early amps have hot glue holding the wires down, perhaps solid core wires held their shape better?

Teflon doesn't melt, but PVC holds it's shape better than Teflon. That's the basis I use wire.

[Bombacaototal]

Many thanks Mark and RG, very helpful indeed

[tubeswell]

What I like about solid core (single strand) hookup wire, is it stays where I put it more easily, so I find it more convenient for lead dressing. YMMV

[Firestorm]

The other thing about solid core is that it's better at transmitting mechanical vibrations.
Since capacitors are all microphonic to some degree, this can do good things or bad things.
I think Ken Fischer knew how to make this work for him.
Just a thought.

[R.G.]

I don't like solid core wire, primarily because vibration can cause stress cracks. It is nice that it stays where you put it better, but you need to use something like a thermal wire stripper to strip insulation off the ends. If you use bladed strippers, they nearly always leave a nick on the wire surface right where the blades cut through the insulation. Vibration stresses concentrate there, and eventually you get a stress crack. It may take a while, and some wires last longer than you will, but still...

If you use solid wire, it makes sense to get something like a PTS-10 wire stripper. These are on the order of $50, and they not only don't nick the wire, they make stripping wires easy, quick, and repeatable as well. I love mine. I'm down to where I get it out for stripping as few as 3-4 wires, rather than impatiently using dikes and notched strippers.

I like the look of cable-laced wiring, done the old-fashioned way with waxed nylon flat lace. With the wire bundle laced, the whole bundle helps take up vibration, and the lace and wire friction damp the vibrations. I've given myself a bit of education developing the skill.

Besides, it just looks vintage-cool.

[Mark]

RG, I'Ve laced wiring in past avionics jobs I've done, but I have been concerned about crosstalk between wires running for several inches. Surely this would also be a consideration when wiring an amp.

Mind you I still find earthing the toughest part of wiring, keeping hum and noise out of an amp can be tough as you increase the gain.

[R.G.]

Crosstalk is always a problem in any cabling scheme. Running wires in parallel for long distances adds inter-wire capacitance. But there is always inter-wire capacitance, just more or less of it.

The ideal situation from the limited perspective of limiting capacitive crosstalk is to use the entire three dimensional space available in the amp to get 100% of the wires evenly spaced in the volume inside the chassis. That's both hard to do and hard to repair. Well, I suppose shielding all wires might do it, but the capacitance per inch of shielded cable also starts inserting capacitances to ground on every signal wire, sucking highs out.

It helps me to get a handle on the numbers. I went off and looked up how to calculate the capacitance per inch and mutual inductance per inch of two "nominal" wires. Turns out that the capacitance is 1.7pF/in, the inductance is 21nh/in. That is - not much. The low frequency of audio and the low currents in most wires saves you. Start talking MHz and you start worrying.

But the secret to low noise and crosstalk is always in knowing the actual driving and driven impedances of each wire. Low impedance wires like signal ground, cathode wires, and to some extent plate wires are not horribly messed up by this. It takes a lot of inches of purely parallel wire for the 1.6pf/in to get a lot of crosstalk going.

Thing is, you don't have to use one giant bundle. Lace up the heaters and other AC wires in one set of bundling. Run a long bundle of low impedance wires down the chassis, letting a wire drop into the bundle and out as needed. Consider a third set of wires, grid wires and high impedance plates, or wires to/from high impedance controls might need special treatment.

Cable bundling and lacing is a tool. You gotta use tools as needed, and only to amount needed, as well as stopping using them before your hurt yourself.

[ChopSauce]

I don't like solid core wire, primarily because vibration can cause stress cracks. It is nice that it stays where you put it better, but you need to use something like a thermal wire stripper to strip insulation off the ends. If you use bladed strippers, they nearly always leave a nick on the wire surface right where the blades cut through the insulation. Vibration stresses concentrate there, and eventually you get a stress crack. It may take a while, and some wires last longer than you will, but still...

Sorry RG, but - with due respect - if you are that much careless when stripping your cables, you should have cut several elements of a stranded cable, which IS - NOT will, may, might or can ... be - a problem, & also may/might/... lead to bigger troubles.

Also, a few turns/angles (sorry for my poor english) alleviate the constraints upon the connectors.

[Mark]

You need to look at the wire with a magnifying glass after cutting the wire. If you typically use cutters or a razorblade there will be nicks in the wire. I went through all of this with my Rocket build.