Cat 5 internal wiring, single strand or multiple?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I understand the meaning of "soundstage smearing" in technical terms. To me, it indicates that the parameterics my brain uses to define the location of a virtual image is being compromised in a time varying fashion as a consequence of some other system response...

One example I would use is program content with a vocal image centered, where a bass note on one channel causes large cone excursion on that channel only. If the sibilance (hf content)is altered in that channel as a consequence of the voice coil velocity changing the hf inductance and series resistance, the resultant single channel modulation may be heard by a listener poised in the sweet spot as the sibilance either drifting off center (disembodied as it were), or simply becoming less location defined.

But I do agree that the terminology in this regard is pretty lacking.

jn

I resisted using the phrase "smeared soundstage" expecting it to be called out as subjective and meaningless but laziness won out and I hoped that an experienced listener would understand the gist of what I was saying.
Your description describes what I was thinking very well.

Here is a link to a Belden white paper on return loss. http://www.belden.com/docs/upload/hdcarltp.pdf

While it is specifically discussing HD video and data networks I think it may be relevant to this discussion.
The authors state that return loss is minor at lower frequencies, but they are talking about preventing data loss.
 
I resisted using the phrase "smeared soundstage" expecting it to be called out as subjective and meaningless but laziness won out and I hoped that an experienced listener would understand the gist of what I was saying.
Your description describes what I was thinking very well.

Here is a link to a Belden white paper on return loss. http://www.belden.com/docs/upload/hdcarltp.pdf

While it is specifically discussing HD video and data networks I think it may be relevant to this discussion.
The authors state that return loss is minor at lower frequencies, but they are talking about preventing data loss.

That paper is all about transferring a signal at the prop velocity and at the characteristic impedance of the cable. The signals they describe have the exact ratio of voltage to current that matches the cable's impedance. For example, a 100 ohm cable will carry a signal which has the ratio of 100 volts and 1 ampere at the cable's propagation velocity, which typically is half lightspeed or faster.

They worry about a reflection getting mixed up in time with later signals.

A 100 ohm cable CANNOT carry an 8 ohm signal at the cable's propagation velocity. That is a violation of relativity.

Audio signals on the other hand, change value so slowly that we cannot easily see the reflections. Cyril Bateman demonstrated this using a reflection bridge, but that was extreme effort and lost on most readers.

Most use the simple RLC lumped element model, but never do they extend that model to the varying impedance of the load, so never look for the variation in settling time. And with full range drivers, nobody considers the dynamic inductance change caused by flux dragging.

jn
 
Last edited:
Marginally less than the square root of jack, providing voltage drop is reasonable & some common sense is shown re the geometry so capacitance & inductance are kept sane (i.e. don't try to reduce one to vanishingly low levels at the expense of putting the other through the roof). ;)

Ye gods, anybody would think speaker wire actually had to do something difficult...
 
Last edited:
Other than it is not physically possible to use 12ga wire with some of the smaller drivers, exactly how much loss of SQ would you expect by using a 24ga twisted pair?

Bob
Within the cabinet? Probably nothing. But why use a wire that's almost invisible. 14, 16, 18...whatever.

Marginally less than the square root of jack, providing voltage drop is reasonable & some common sense is shown re the geometry so capacitance & inductance are kept sane (i.e. don't try to reduce one to vanishingly low levels at the expense of putting the other through the roof). ;)

Ye gods, anybody would think speaker wire actually had to do something difficult...

He asked about within the cab, no? I'd twist em so they don't rattle.

jn
 
Inverting the question, why not, if voltage drop is within acceptable limits & it can handle the current safely? A twisted pair from a run of Cat5 is usually fine for such duties.

One would assume that people are not so asinine as to leave wires hanging about potentially rattling against the box, each other, or anything else in the first place. Bob (to put it mildly) isn't.
 
Last edited:
One would assume that people are not so asinine as to leave wires hanging about potentially rattling against the box, each other, or anything else in the first place. Bob (to put it mildly) isn't.

I've not assumed that.

timdoug asked about within cab, where I said stuff can rattle.

You seemed to be speaking about geometry, L, and C, which seems to be more of an amp to speaker run thing.

jn
 
Groan. That was a generalised remark, not one specifically referring to internal wire. It is in 99.99999% of cases a non-issue inside speaker boxes as you are perfectly aware. There might be a handful where ludicrous runs are present for some perverse reason, which would seem like a good reason to avoid them, although I rather suspect there would be more significant issues present with a design that required such extensive amounts of internal wire.
 
Groan. That was a generalised remark, not one specifically referring to internal wire. It is in 99.99999% of cases a non-issue inside speaker boxes as you are perfectly aware. There might be a handful where ludicrous runs are present for some perverse reason, which would seem like a good reason to avoid them, although I rather suspect there would be more significant issues present with a design that required such extensive amounts of internal wire.

We agree. Your inverted question, sure 24 would work and be ok in general, but for me it's just too small except perhaps for a tweeter (but this is a full range forum). I'd like at least 16 and stranded for in the box myself.

jn
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.