A question about cables

[adityamunshi]

What kind of cables/wires do i need to get for a simple setup consisting of a 60x4 or 75x4 RMS Amp and 4 speakers ?

Someone's going to get them from USA for me and i need to specify exactly what i need.

Is it okay to get them from crutchfield or are there other better sites ?

Do i need to get both power cables and speaker wires ? Or is it better to use a power cable from finolex etc. ?

[vikram_d]

If you have only one amp and 4 speakers then you will need a 8 gauge wiring kit and two pairs of RCA cables. You can look at brands such as audison, monster, scosche etc etc.

If you have two amps then you will need a 4 gauge wiring kit.

[panky12345]

If you are bent on getting from US, get a decent 4 channel 4 gauge wiring kit, go for monster/scosche. You wont find good deals on crutchfield, try etronics. In case its same money - wise, next best option would be connection audison. (PM gunbir for details)

power cable: finolex is good. no need to get from US.

[blueraven316]

Scosche/Monster are very popular in the US.
Other than Audison You can also look at kicker wires, though not available with everyone but is of really good quality.

[gunbir]

Originally Posted by panky12345

power cable: finolex is good. no need to get from US.

Let me try and clear this up... While finolex et al is great for budget installs, there IS a reason why specialized power cable exists for car audio.

There ARE proven performance gains in using multi-stranded cables as they can flow larger amounts of current than the economical equivalent of the same gauge.

Electricity travels on the outside of the conductor and NOT through it. Thats why the multi strand power cables for car audio contain more (sometimes twice or more) strands than a regular cable of the same gauge.

Moreover the quality of copper in these cable is higher in quality cables over economy cables. Quality cables will be made from oxygen free copper which will ensure corrosion free connectivity and better transfer.

And lastly, the flexibility of quality car audio cables is way ahead of household cable and in our small cars where space is aways at a premium, flexibility is an asset.

[adityamunshi]

I cant find any monster/audison wiring kits on either crutchfield or etronics. Any suggestions ?

[vikram_d]

try Car Audio Video - Car Subwoofers - Car Amplifiers and Speakers

Also like Satya has mentioned look for Kicker.

e2 E400 by Scosche - e2 400W Single Amplifier Wiring Kit • 6.5mm power/ground (equivalent in strands to most other "8 gauge" kits) • 17' Twisted Hex RCA Interconnec Cables • 17' power and ground - , Car Installation & Accessories, Amplifier Installat

[DerAlte]

Originally Posted by gunbir

There ARE proven performance gains in using multi-stranded cables as they can flow larger amounts of current than the economical equivalent of the same gauge.

Electricity travels on the outside of the conductor and NOT through it. Thats why the multi strand power cables for car audio contain more (sometimes twice or more) strands than a regular cable of the same gauge.

Yes and no! (Navin: I'll try to keep it light to reduce the fear factor; Gunbir: sorry, I am not trying to disprove your point)

Due to eddy currents produced by the main current, current density decreases exponentially from surface to core:
J = Js * e^(-delta/d), where:
J = current density at any depth 'delta' below surface
Js = current density on the surface
d = skin depth constant

The skin depth constant is calculated as:
d = √((2 * ρ)/(ω * μ)), where
ρ = resistivity of conductor
ω = angular frequency of current = 2π * frequency
μ = absolute magnetic permeability of the conductor

If one plugs in values, one finds that the skin depth is
8.57mm at 60Hz,
0.66mm at 10Khz,
0.21mm at 100Khz,
0.066mm at 1MHz,
0.021mm at 10MHz, etc.
Most significantly, for direct current (frequency = 0) the depth is infinity, i.e. the whole material conducts current.

So, for the power cables, whether one puts Kicker or Scosche or Finolex or even a solid copper bus bar, it is one and the same.

For speaker cables and shielded signal cables the scene would be different, but only to a very limited extent depending on the range of frequencies to be transported. Let us gun for the 100KHz range to take care of all possible harmonics in the signal.

Definitely (n strands of 0.21mm) will be better than (n/3 strands of 0.66mm). Not sure if the wire specs are written precisely on the package of the cable set. So, perhaps someone can take a micrometer and compare the strand composition of the different brands?

IMHO, the cable sets are for convenience and the brand carries a mystique; but quite definitely the same cables would be available with Indian brands.

[low_bass_makker]

Thank you Deralte for the same. I would have written the same but without any equations and other minor details. The current is passed through the conductor and not through the surface.

Rest about detailed comparison of Branded Car audio cable and finolex coming up in few mins.

[navin]

Originally Posted by DerAlte

Yes and no! (Navin: I'll try to keep it light to reduce the fear factor; Gunbir: sorry, I am not trying to disprove your point)
Most significantly, for direct current (frequency = 0) the depth is infinity, i.e. the whole material conducts current.

So, for the power cables, whether one puts Kicker or Scosche or Finolex or even a solid copper bus bar, it is one and the same.

The real advantage multi-strand POWER cables offer over solid core is flexibility. Multi strand cables can be laid more easily than a bus-bar.

[gunbir]

Originally Posted by DerAlte

Gunbir: sorry, I am not trying to disprove your point)

Hey, come on its all good! We are all here to share and learn.

[adityamunshi]

What if i get two of these ?

EFX 17-foot RCA Patch Cable at Crutchfield.com

[s0uljah]

Have used upto 25sq mm finolex in most of my friends setups with great success. Its not as flexible but hey when your saving $$$$ why not. Extra money was spent on RCA's and speaker cable

[nishantgandhi]

I have a similar query. I need to know which all cables/wires would I need to tell the installer for this setup: A simple setup consisting of a HU and 4 speakers ?

Which brands (Indian/Phoren?) and at what price?

[low_bass_makker]

Ok took out few of my instruments and did some measuring.

Test was a comparison of two different wires.

1) normal household 25 mmsq wire.
2) good car audio cable 4 awg.

Cross section area.
I took both the wires cut is about 3 inches to make the inside copper visible . I used a 1 micron Mitutoyo micrometer for the same to get accurate result. Few pics before the calculation part.

The normal house hold wire



The Good car audio cable.




Ok in the house hold wire had 158 strands. The diameter of each wire strand is 0.44 mm so the section area comes to.

0.44 / 2 = 0.22 (radius)
0.22 x 0.22 x 3.14 = 0.152 (section area of one strand in mmsq)
0.152 x 158 = 24.016 mmsq

So the normal house hold wire company fall short by approx 1 mmsq from what they claim it to be so it is less than 1 % short.

Now comes the The Good car audio cable, it has total of 1078 strands and the diameter of each strand of 0.15 mm so the section area comes to.

0.15 / 2 = 0.075 (radius)
0.075 x 0.075 x 3.14 = 0.0176 (section area of one strand in mmsq)
0.0176 x 1078 = 19.04 mmsq

Energy solutions - Metric Cable size to AWG Conversion

Normally if we take 4 awg wire it is compared to 25 mmsq indian wire so we are 6 mmsq short that is nearly 25 % less. But according to the American standard it is 21.3 mmsq so we are approx 9 % short still.

Now comes the flexibility part. The pic first.



Both the cables are flexible but the Car audio is a bit more. But I dont think the normal house hold wire is quite flexible for the job of car audio install IMHO.

The outer sheath of the car audio cable is soft to keep it flexible but the normal home hold wire was a little hard not easy to cut also, which I will take as a good thing.

The outside diameter of the household wire is 11.1 mm and that of the caraudio wala was of 10.5 mm. It show that the insulation is thicker in the case of caraudio wala cable.

The cost of the House hold wire is approx 125 per meter. And that of the Good car audio cable is 650 per meter. Do the maths which is better.

So finally I would recommend the normal household cable for the power wiring of the amp any day. For speaker and RCA get good brands as they directly affect the SQ.

About the copper purity test can be done of both the wires If the users of the forum encourage me to do that.