El cheapo speaker wire

[speakerbug]

Hi

Being a skinfint, I plan on making my own cable with off the shelf 12 awg copper speaker wire. I have found a place (in Chinatown NYC) that sells 100 ft for $20.00. It looks like regular copper wire, but, aside from the high end stuff, isn't copper wire basically interchangeable?

Thanks

[planet10]

Originally posted by speakerbug
Being a skinfint, I plan on making my own cable with off the shelf 12 awg copper speaker wire. I have found a place (in Chinatown NYC) that sells 100 ft for $20.00. It looks like regular copper wire, but, aside from the high end stuff, isn't copper wire basically interchangeable?

Not at all... the amount of oxygen in the wire makes a difference. Also the amp & speakers you are stringing the speaker wire between -- what are they?

I tend towards CAT 5 strands as anyone with an IT dept handy can get it for free (and unless someone pays you to take it away, that is the ideal Frugal-phike(tm) cost) and the copper is high purity. I just use as many strands as i need to achieve my current requirements (usually low with my mains so i just use a pair of 24g strands)

dave

[gtforme00]

Originally posted by speakerbug
It looks like regular copper wire, but, aside from the high end stuff, isn't copper wire basically interchangeable?

Thanks

From Wikipedia: http://en.wikipedia.org/wiki/Oxygen-free_copper

Oxygen-free copper is typically specified according to the ASTM/UNS database [3]. The UNS database includes many different compositions of high conductivity electrical copper. Of these three are widely used and two are considered oxygen-free.

* C10100 - also known as Oxygen-Free Electronic (OFE). This is a 99.99%pure copper with 0.0005% oxygen content. It achieves a minimum 101% IACS conductivity rating. This copper is finished to a final form in a carefully regulated, oxygen-free environment. Silver (Ag) is considered an impurity in the OFE chemical specification. This is also the most expensive of the three grades listed here.

* C10200 - also known as Oxygen-Free (OF). While OF is considered oxygen-free, its conductivity rating is no better than the more common ETP grade below. It has a 0.001% oxygen content, 99.95% purity and minimum 100% IACS conductivity. For the purposes of purity percentage, silver (Ag) content is counted as copper (Cu).

* C11000 - also known as Electrolytic-Tough-Pitch (ETP). This is the most common copper. It is universal for electrical applications. ETP has a minimum conductivity rating of 100% IACS and is required to be 99.9% pure. It has 0.02% to 0.04% oxygen content (typical). Most ETP sold today will meet or exceed the 101% IACS specification. As with OF copper, silver (Ag) content is counted as copper (Cu) for purity purposes.

With 12AWG wiring, for any conceivably practical length, the type of copper makes no practical difference on the resistivity. In fact, unless the wire is OFE (very expensive), there is no difference in conductivity between normal oxygen free wiring and normal universal copper wiring at all.

There are two measurable effects of speaker wires on audio sound. One is the effect that the wire has on the stability of the amplifier, the other is the effect that the resistance of the wire has on the Qts of the speaker enclosure. The latter only occurs when the wire is very resistive compared to the speaker load, and can be discounted for 12AWG wire of any reasonable length.

The stability of the amplifier can be affected by the capacitance and the inductance of the speaker wires, though for any reasonably well designed amplifier with any reasonable speaker cables (your zip wire included) this should not be an issue.

The amplifier could conceivably also be affected by RF pickup from the transmission line effect of any length of wire, though again for any reasonable amplifier and cable length this is again a non-issue.

See Rod Elliott's page for information about this, but the short answer is that you certainly may use the wire you have found.

Regards,
David

Edit: I once believed that cables had a major effect on the sound. This was because I had used CAT5 wire on my speakers and heard an increase in bass response. What I was hearing was the increase in Qts referred to above. I would much rather use a properly sized enclosure than use speaker wire as a resistor for this purpose!

[planet10]

Originally posted by gtforme00
though for any reasonably well designed amplifier with any reasonable speaker cables (your zip wire included) this should not be an issue.

That is a slippery slope. What defines a well designed amp? A really well designed amp coule be one that has a specific loudspeaker to drive and the speaker and wire are rightly part of a system

Any amplifier designed to be unconditionally stable into most any load is likely a compromised design as far sonics go (but within limits does define most commercially available amplifiers)

dave

[poynton]

Originally posted by planet10


.............. Frugal-phike(tm) .............

Is CAT5 O2 free ?

[planet10]

Originally posted by poynton


Is CAT5 O2 free ?

No wire made or used in the presence of oxygen is totally O2 free, but CAT 5 is pretty good, and we have the benefit of low cost due to the billions of miles of it made for the computer industry.

The economies of scale can even be seen with the removal of legislation requiring pleum grade inside walls, the price of teflon coated CAT 5 jumped from a bit more than PVC to WAY more.

dave