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Chippy_boy
19-11-2009, 16:25
The Mrs and I have been thinking of having a re-arrange of our lounge furniture / hifi and unfortunately the WAF effect has reared its ugly head again.

Currently I have my power amp in the middle of the speakers and fairly short speaker cables, but in the new setup, she is point blank refusing to have the power amp in the middle of the room. Women eh! ;-)

I would have to put the power amp to the left of the left hand speaker and run the speaker cable all the way from there to the right hand speaker (around the fireplace). I guess the cable would to be in the region of 8m long. I realise I would need an 8m pair even though the left speaker would only actually need 1 or 2m.

What's the consensus on how much this will matter to the sound quality? (i.e. 8m speaker cables vs my current 2m cables) Will the sound be impaired at all, do you think?

The (probably better) alternative would be to get 2 mono power amps and run a long interconnect. But that has it's drawbacks - I would have liked to be able to use a passive preamp, and that would be out of the question. Plus I'd have to sell her on 2 amp boxes instead of 1 - in itself not a trivial task.

What's your thoughts? (Other than divorce, obviously!)

alb
19-11-2009, 16:56
It's not ideal, but neither is my 9m speakers cable run. I noticed no deterioration
when changing from 4 metres.

The Grand Wazoo
19-11-2009, 17:07
Here's a simple solution - Buy single a 10 metre cable. Chop 2m off.
Bingo! You'll have a set of cables that have been custom made specifically for your installation & your wife'll think you're fantastic!

I used to use different lengths when room geometry dictated. Cost didn't come into it because I had loads of cable to use but I could'nt detect a single shred of difference, and believe me, I tried.
Now my amps are between the speakers so I'm back to equal lengths but I wouldn't worry about going back to how it was. I've never met anyone who tried it that disagreed with my assessment.

I think it's all a con originating from cable manufacturers trying to sell more than you need. As if they aren't making enough bleedin' profit from their overpriced wire already.

Chippy_boy
19-11-2009, 18:43
So the general consensus is that an 8m cable will sound identical to a 2m one?

I really would have like to keep the cables "short" so the amp has better grip of the speakers. Or is that just a myth?

The Grand Wazoo
19-11-2009, 19:13
If I were you I'd want to try it to confirm for myself, but that's my experience. I'm sure others will disagree with me, but has anyone else has actually tried it?

Themis
19-11-2009, 19:24
I tried it once and needed to back the shorter cable speaker for about 3cm to get a precice image. Perhaps the SF are fussy or perhaps I imagined it.

Anyway, since then, I laways buy same cable length : it's easier to sell it afterwards. ;)

Barry
19-11-2009, 19:42
Let's do some sums.

Assuming that the insulation used for your speaker cables is PVC, the extra 7 metre length will cause an electrical delay of no more than 50ns. That's 1/1000 th of a cycle at 20KHz or a phase delay of 0.36 degree. Don't think that will be at all audible.

Having equal cable lengths appeals to one's sense of symmetry, but is not essential. Some may disagree and claim to hear a difference.

Unless you use something the size of welding cables, a typical speaker cable will have a loop resistance of 0.015Ohm per metre. Your speaker leads will thus introduce losses of 0.016dB and 0.065dB (assuming a nominal speaker impedance of 8Ohm). Can you hear a difference of 0.05dB?

In my own set up, the speaker cables are ~6m and ~16m long; a difference of 10m. Measured loop resistance is 0.1Ohm and 0.2Ohm respectively. The ohmic loss is thus 0.05dB and 0.11dB respectively. With an amplifier output impedance of 0.03Ohm, the damping factor (again relative to 8Ohm) is reduced from 250 to 62 and 35 respectively. I hear no difference; deviation of the room from a mirror symmetry will cause greater audible change that that caused by unequal cable lengths.

So in support of Chris's reply: don't worry about it.

Regards

Themis
19-11-2009, 19:54
I don't disagree technically. Certainly a product of my imagination.

Nevertheless, same length makes it easier to change the relative position of the amplifier in the future.
And also, allows the re-selling of cable on a cable swap (nobody will buy a cable of 2m and one of 8m...)

The Grand Wazoo
19-11-2009, 20:40
And also, allows the re-selling of cable on a cable swap (nobody will buy a cable of 2m and one of 8m...)

Well, maybe not, but someone will buy a pair of 2m cables & someone else a pair of 3m cables (& probably for a higher price than a pair of 5 metre ones). And Chippy will have saved himself the cost of 6 metres of cable he doesn't need.


I don't disagree technically. Certainly a product of my imagination.

When you make an investment, your brain has to justify it and the hype you've been fed supports that. This is why I made the point that when I tried it, cost wasn't in the equation.

Themis
19-11-2009, 20:49
When you make an investment, your brain has to justify it and the hype you've been fed supports that. This is why I made the point that when I tried it, cost wasn't in the equation.
Well, to be true, in my case, this didn't happen this way.
I lived happily with a 2m and a 5m cable for 4 years. Then, when I changed speakers, it didn't fit me anymore. So I changed it.
Nothing to do with the price, actually, I use bulk cheap cable. ;)

The Grand Wazoo
19-11-2009, 21:13
Yes, sorry, I was making a general comment about how we work rather than presuming to know all about the workings of your brain!!

Themis
19-11-2009, 21:17
Yes, sorry, I was making a general comment about how we work rather than presuming to know all about the workings of your brain!!:)
(I'm too old for this sh!t (c) Roger Murtaugh):lol:

DSJR
19-11-2009, 21:27
Odd lengths of, say 3 and 5m, or 7 and 9m won't make any noticable difference IMO, as long as the cable is a decent gauge. I used 7 and 9m runs in the past, both at home and at work and my current lengths are around 6 and 4m.....

I'd possibly comment that transformer coupled valve amps need shorter lengths of chunky wire with modern speakers, which are 4 to 6 Ohm nominal, although my Crofted Quads coped with hifi dave's very lengthy runs in his dem room (hint - Glenns Series 7 amp coped even better ;))

Alex_UK
20-11-2009, 07:08
In my experience I have never noticed a difference going from short to long cables, or running two different lengths, although as I am running very reasonable Mark Grant cable I said sod the expense and bought 14m for two 7m cables, though one only needs to be 3m - here's a point to consider - coiling the extra 4m (or whatever) would potentially be worse than having a straight run of shorter cable. Discuss! (OK, don't bother!)

NRG
20-11-2009, 07:53
.....

I'd possibly comment that transformer coupled valve amps need shorter lengths of chunky wire with modern speakers, which are 4 to 6 Ohm nominal, although my Crofted Quads coped with hifi dave's very lengthy runs in his dem room (hint - Glenns Series 7 amp coped even better ;))

Yes, especially if SE zero feedback which generally have poor damping factor to start with...adding extra cable length can cause some interesting problems in the bass.

anthonyTD
20-11-2009, 19:04
Yes, especially if SE zero feedback which generally have poor damping factor to start with...adding extra cable length can cause some interesting problems in the bass.
quite agree!:)
A...

Mike
20-11-2009, 19:16
Yes, especially if SE zero feedback which generally have poor damping factor to start with...adding extra cable length can cause some interesting problems in the bass.

Yep... experienced that. Going from 10m to less than 2m made a world of difference. But that in itself caused further problems. :doh: