18 AWG center conductor is a tad thin for speaker cable.
John is using 2.5mm sq area which is about 1.8mm dia, but he is doing long runs so the larger diameter makes sense.
I normally run 14AWG for primary speakers and subs, which is roughly equivalent to 1.6mm dia.
For surround speakers I run 16AWG which is equivalent to about 1.3mm dia.
I would recommend the 1.3mm dia minimum for primary speakers with runs of 3M or less. Beyond 3M I recommend stepping up to the next larger wire gauge.
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I don't know about coax for this. In my experience it is rather stiff due to the shield layer(s) so might not lie flat on the floor. The solid inner conductor is stiff too. You need a high ratio of weight to stiffness.
Top tip: mains earth sleeving filled with liquid mercury (or brown live wire sleeving to match the cork floor).
Top tip: mains earth sleeving filled with liquid mercury (or brown live wire sleeving to match the cork floor).
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Thanks. I'm thinking 18 AWG would be my absolute minimum. The longest run is approx 10 feet, I don't play at any great volume and there isn't much EQ on the woofers/subs, they are U-frames. I'm planning on a IB sub for the very low stuff and that will use different cable entirely as it won't be running across the floor
I don't know about coax for this. In my experience it is rather stiff due to the shield layer(s) so might not lie flat on the floor. The solid inner conductor is stiff too. You need a high ratio of weight to stiffness.
The piece of shark wire I have is just about flexible enough, it's stranded core, but I take your point about shield.
At the moment I'm using brown mains wire twisted 🙂 If there is such a thing as the clear sheathed speaker wire twisted instead of figure 8 I'd have a look at that....I could split some then twist it, but I can't see that working too well from past experience with the mains wire?
I like the mercury idea.......
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A lot depends on the efficiency and impedance of your speakers.
I am running 8 ohm speakers and based on the nominal impedance I try to stay under 3% equivalent speaker cables. Ideally I like to stay below 1% based on cable resistance and nominal impedance.
I am running 8 ohm speakers and based on the nominal impedance I try to stay under 3% equivalent speaker cables. Ideally I like to stay below 1% based on cable resistance and nominal impedance.
I'd say resistance below 0.5 ohms is probably fine, below 0.1 ohms is definitely fine.
According to this: Electrical Wire Gauges
For a 3m length (Wales is in the UK where we use the metric system at least until the end of March) you have 6m of wire. So between 16 and 24 awg.
Caveat: I've never tried really thin cable so I can't predict for sure. There may be other significant factors than dc resistance. I usually buy with my eyes; does it look chunky enough?
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I looked through some old photos and found that nice, flat speaker wire I used, it was called "Synapse(TM) Sliver Series Thinflex Professional Speaker Cable by Belkin", and it has an arrow with "Signal Flow" next to it, so you know it is good. It's about 1m from where it is soldered on the amplifier circuit board, to where it is soldered on the driver terminals, maybe a little less, so I think I am good. I don't remember which way the arrows point, straight up I guess.
Here's an interesting pdf containing a table linking damping factor and SPL loss to wire gauge and cable length.
http://www.diy-audio.narod.ru/litr/dampfact.pdf
http://www.diy-audio.narod.ru/litr/dampfact.pdf
If we're looking for off-piste ideas, then how about this 10mm wide, self adhesive copper foil?
Once stuck to the cork flooring, it could be sealed with varnish to make it footwear friendly!
http://www.farnell.com/datasheets/2025570.pdf
P.S. I'll leave it up to SJ to calculate the resistance per metre! 🙂
I began to wonder, two drivers in series, will the coil resistance of one effect the damping of the other? http://www.cartchunk.org/audiotopics/SeriesSpeaker.pdf
The author has rather an unfortunate name
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I've read a thesis by Willy Bore who says to regard the two series speakers as being equivalent to one big speaker and fuhgeddaboutit! 😎
Try looking for drag chain cable. It's really high strand count for flex.
I looked through the Helukabel catalog, but the colors won't float your boat.
But they aren't the only ones out there.
John
Why not solid or gas Mercury? -38 degrees (either way) is not THAT cold. +350C +674F is good searing barbecue heat.
Anyway: an early implementation of One Ohm was a 1mm tube of Mercury about 1 meter long. Yes, Mercury is that bad a conductor! Hg in 1mm sleeving 3 meters out and back is near as much resistance as the typical speaker. By the time you increase the diameter to get the Ohms down, you'll be registering as a Toxic Metal site.
So, the answer is no. Also the cable and Zo will be less significant. The question remains whether they were significant to begin with.
Two "identical" speakers series act as a single speaker. Normal production variations no big deal.
Two *different* speakers series gets complicated.
Two *different* speakers series gets complicated.
You are absolutely right. Mercury has over 50 times the resistivity of copper. I didn't bother to check this as I never expected anyone to take this idea seriously. 😛
I still think mercury has artistic merit. Imagine, say, channels carved through your floor containing rivers of mercury through which the sound travels silently to to your speakers. The reflections of ancient Egyptian torches glinting in the smooth silver meniscus.
Yes I have been drinking.
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Probably better to consider damping without the complication of a 'figure of merit'.
Mercury vaporises readily at room temperature, so scottjoplin could end up as mad as a hatter!
Erethism - Wikipedia