Why is 3m of Naim Super Lumina enough?

Does it really matter? Provided 3m reaches your speakers, the fact that Naim supply such lengths makes it a safe assumption that they will work well with Naim amps. 

Each length of SuperLunina has a resistor in one end in the little box that spans the twin cables. I would assume that this component is responsible for 'matching' the cable to the input of the power amp and would further assume that the value of this component varies according to the length of the cable.

Others with more technical knowledge will know more.

I never imagined that length was so important

The Strat (Fender) posted:

I never imagined that length was so important

Well I manage just fine with a mere 3m.

Ooohhh......errrr......missus.

I take it that the 3m, 5m. 7m and 9m are standard lengths to allow dealers to have standard stock available (since the resistor in the block at the amp end varies in value depending on cable length - it just connects the two outer screens together). Custom lengths are available from Naim if required. Unlike the SL interconnects, the speaker cables can be used with other amps which don't need the minimum cable length so in this case 3m would be perfectly acceptable (and TBH is not really an issue for the Naim kit either) 

James

Hi NigelB -

Apropos the science, is it really known that a resistor (as opposed to a capacitor or inductor) is added and used to tune the cable’s ac response? From a conductance perspective (which is the first order characteristic of a connecting wire after all), resistance is futile (haha) and it’s always been concerns about reactive loading (ie C and L, nor R) that I’ve seen being raised in terms of what the classic series Naim amps want to “see” at their output... and milliohms per metre tends to support this (noting milli is a tiny prefix for resistance while micro - a thousand times smaller- is normal for inductance and pico - a million times smaller still - for capacitance). Thanks for thoughts from anyone who has heard this in a definitive context, especially if I’m really missing the thread here!

Regards alan

It's worth reading the critic review which mentions the resistors purpose. 

James

james n posted:

I take it that the 3m, 5m. 7m and 9m are standard lengths to allow dealers to have standard stock available (since the resistor in the block at the amp end varies in value depending on cable length - it just connects the two outer screens together). Custom lengths are available from Naim if required. Unlike the SL interconnects, the speaker cables can be used with other amps which don't need the minimum cable length so in this case 3m would be perfectly acceptable (and TBH is not really an issue for the Naim kit either) 

James

Just to correct myself - I forgot that you can get the interconnects in non DIN configurations so you can fully SL your non Naim system too 

james n posted:

I take it that the 3m, 5m. 7m and 9m are standard lengths to allow dealers to have standard stock available (since the resistor in the block at the amp end varies in value depending on cable length - it just connects the two outer screens together).

What I want to know is - what is the purpose of the identical, but empty box at the speaker end?!

james n posted:

It's worth reading the critic review which mentions the resistors purpose. 

Thanks James - I was confusing the rfi shield (with the bleed resistor as explained in the review) with the other discussions of total cable inductance and capacitance (functions of the length)... two separate concepts in one short thread was too much for me today haha. 

Regards alan

ps edit: ...but I am still puzzled over the length dependent resistance choice... some other reason I guess, but it’s still for shielding, not presenting a “preferred” reactive load to the amp... hmm

apparently inductance values at audio frequencies for Superlumina cable is different than that measured at DC frequencies (according to what Naim HQ told me).

Anyway - since Naim made Superlumina.... simpler to just trust them?

The Strat (Fender) posted:

I never imagined that length was so important

A5 lenght importance was created by JV

SL lenght was created by ?

Marketing

Accountant

Investors

I decided to change my NAC5  for SL after years of NAC4 and 5 both under a rug in the middle of the room. A right pain I can tell you!

The rest of the room has an exposed wooden surround floor where the speakers are each side of the fireplace. Kit at the other end of the room. A bit off topic perhaps, but I decided to "loose"  the LS cables completely under the floor. There are two holes in the wood behind each speaker with pipe-wrap inserted into each hole to  accommodate Naim's little black boxes and for neatness as well. Same at the other end. As the suspended floor is about 600mm above a concrete slab. I did not want  the cables resting on the slab with dampness or worse. Water ingress?

Both cables are supported  off the joists. We thought 6 mtrs would be about right but went for 7 mtrs which was a wise choice to avoid  any "pull". I thought under floor cabling might have an effect in the winter. but central heating pipes run in the area.

Once run in no going back and there are no visible cables to annoy herself.

Douglas.

Perol posted:

The Strat (Fender) posted:

I never imagined that length was so important

A5 lenght importance was created by JV

 

SL lenght was created by ?

Marketing

Accountant

Investors

 

 

Complete nonsense post.

analogmusic posted:

Perol posted:

The Strat (Fender) posted:

I never imagined that length was so important

A5 lenght importance was created by JV

 

SL lenght was created by ?

Marketing

Accountant

Investors

 

 

Complete nonsense post.

And i’ll Tell you why.

if marketing, accountant and investors set the required length it would be more like 5 metres with the price to match. Let’s hope they’re not reading this

I’m not so sure. The standard lengths do mean that it is more of a pain to so for four or six metres. Having only 3 metres even if it fits leaves for some a doubt that it is long enough - so they might buy 5 metres anyway, which I think this thread implies. 

Im still on NACA5 atm ????

Drewy posted:

analogmusic posted:

Perol posted:

The Strat (Fender) posted:

I never imagined that length was so important

A5 lenght importance was created by JV

 

SL lenght was created by ?

Marketing

Accountant

Investors

 

 

Complete nonsense post.

And i’ll Tell you why.

if marketing, accountant and investors set the required length it would be more like 5 metres with the price to match. Let’s hope they’re not reading this

I'm sure Naim created a Lumina cost-benefit analysis

Cable niche usually provide mega profit, the worst I can think of is Nordost, Vertere and with Lumina, now also Naim, I'm surpriced Linn didn't jump the wagon long ago. Their Silver interconnect are cheap by todays standard. I'm sure if they gave it another color, another name and perhaps minor changes and tripled the price, Linnies would be all over exited

J. Vereker hardly speculated in these lines when he launched A5, was it £5/ mtr ?

His message was basically how long lenght needed as minimum

again nonsense.

Naim created Superlumina as an engineering led project for statement.

while the prices aren't to everyone's liking, the performance is right up there with the best hi-end cables.