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What size twin and earth cable?
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having read various threads, twin and earth cable has been mentioned as very good to use with home cinema systems.
my question is what size cable should i be using, bigger the better?. as i was recently in b+q i notice they do 10mm thick.
any help would be appreciated
thanks
graham
my question is what size cable should i be using, bigger the better?. as i was recently in b+q i notice they do 10mm thick.
any help would be appreciated
thanks
graham
0
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Solid core cable, as used for fixed wiring.
The stuff used for extension leads is 3-core flex.
1.5mm lighting cable is fine for surround speakers or low powered stereos. Use 2.5mm for the front and centre speakers on higher output amps.
Note that the sizes (1.5mm, 2.5mm) refer to the cross-sectional area of each conductor, not the size of the external plastic sheath. IIRC, the biggest size used for domestic wiring is 6mm, for electric cookers.
Lighting circuits use either 1mm or 1.5mm, ring mains use 2.5mm.
Thicker is usually better in most cases, although he HiFi folk will tell you all sots of things about being oxygen free etc etc...
No, you don't need the earth wire, but the idea is to use solid-core cable. AFAIK, you can't buy twin solid-core, so the choice is between twin & earth solid, or twin flex.
Solid really does sound better than stranded/flex.
While "thicker is better" is normally true for stranded cable, it's not necessarily true for solid. IIRC, it's something to do with "skin effect", where the charge flows at a different rate on the surface of the conductor, to the centre of the conductor.
If you are using solid-core, it is best to use the smallest cable that can handle the peak current. Thicker cable will give a slight roll-off to high frequencies.
I am no expert (A-level physics, 30 years ago!), but I have experimented with cables, and I am convinced about these effects....
The 2.5mm one is what I got for my two front speakers and my centre. I have left QED original for the rears.
I used this to replace QED Silver Anniversary (5.99 per metre) and it sounds better to my ears.
Watched Hero yesterday and the scene with the arrows at the Caligraphy school sounded amazing.
As a contrast, mains type twin and earth has good electrical properties. Bigger the better to get the resistance low. Depends a lot on length of the cable as to how thick it should be. This type of cable is made from standard grade copper, which by dint of the manufacturing process is about 99.9% oxygen free. The 99.9999% oxygen free copper used in audiophile cables makes little difference - just adds slightly to the resistance.
'Skin effect' does make a very slight difference. It can change the effective resistance of the cable to high frequency audio signals. It may mean that a 20kHz tone is down by 5% in worst cases. This is not normally noticable - especially for people over the age of 15, whose ears cannot hear such a high pitch anyway. :eek:
I use Shark 12AWG cable from Maplins. It is reasonably priced at £15 per 10 metre drum. More expensive than twin and earth but looks a lot better and much less of a pig to handle than T+E.
What colour is it and is it more flexible than the t and e.
I have also made the CAT5 cable and it is fine but it is a pig to make.
Another thing which I get from Maplins is their heatshrink tubing (F-70 type), which can be used to make connections to banana plugs, etc. airtight. This should prevent the copper oxidising and turning green.
Regards,
diablo
Diablo how do you do the heatsink bit still havent a clue what is for and how you get it to fit on the cable.
Copper is wonderful stuff for connections but if it is exposed to the air then it will go green and manky after a while. I suspect that it causes problems with the sound before the effect is really noticable visually.
Cable company QED make a big thing of this, and I suspect that they may actually be right. See their blurb here.
I use the heatshrink stuff to do much the same thing.
I get banana plugs with push-on flexible red/black 'covers'. The cover bit is put onto the lead followed by an inch and a half of F-70 heatshrink sleeving, then the actual banana plug is fixed to the wire. The heatshrink can then be pushed over the body of the plug and shrunk by heating with a hairdryer or something. After which the cover can be pushed over the top of that. Gives an airtight seal to prevent corrosion.
A lot of connections between amps and speakers just use bare wires. If this is the case then it's a good idea to leave a few inches spare at each end so that you can chop off the exposed part and strip back a new section of wire every few months.
I'm convinced that part of the reason that people say that new speaker cables sound better than the old ones is that the old ones are suffering oxidation / corrosion. They might hear the same improvement if the old ones were cleaned up.
I'll stop typing now as I'm starting to ramble. :rolleyes:
diablo