Naim interconnects are usually a maximum of about 1.2m long and since 1989 have the lock ring din plugs on them.
Some carry audio and power and are known as Snaics. These are usually either 4 pin or 5 pin 240 degree pin configuration.
Early ones before about 2002 were grey, newer ones were black.
Same cable, it's just Bicc who made the cable changed the outer sheath colour.
Claims of sound quality difference are usually down to the fact that the grey ones are correspondingly older, and usually the din plug pins are more tarnished!
The other interconnects that naim used are those that carry signal only ie. no power.
These usually have thinner cable (about 5mm outside diameter as supposed Snaics which are about 7mm diameter).
The signal only interconnects usually have 5 pin 180 degree din plugs.
The cable used on these was always grey due to naim's chosen supplier. I believe it is these leads that are nicknamed lavender.
If looking at older leads - aways clean the pins and check for fractured solder joints.
All naim din leads made before the end of 1989 ( when the olive range kit was launched) used the older style latching din plugs with a little catch and not a ring to lock them in.
With these, due to age cleanliness of pins is even more of an issue.
There is no rocket science with any of these leads and I have used longer ones up to about 4m using same type of plugs and cable.
Being din there is a lot of practice needed in soldering and care in the way the screen is grounded.
If you carefully cut open an old lead you will see how it's done.
It takes about an hour to make and test such a lead - so you will see where the cost comes from if based on uk labour rates and profit margins!
Close, but not quite. A few points of order:
Black SNAICs were introduced in 1998 or 99. There was an initial run that was a harder cable sheath (shinier) and IIRC had green branding. The next run was softer sheathing, white imprint, and sounded better. This difference in black SNAICs was not publicised. Both sounded better than the grey SNAICs that preceeded them. SNAICs carry signal and sometimes power between power supplies and amps, and preamps. They were included with amplifiers and power supplies.
Remember, Cannon XLR connectors were used on the NAP250 and 135 SNAICs, rather than 240 degree DINs.
Black SNAICS were demonstrably better against new Grey SNAICS; the differences are not down to age of cables.
The NAIM interconnects were grey cable DIN-to-DIN connection, and were included with sources. The "lavender" interconnect came about in 2000 or 2001 (from memory); it wasn't fully pink, just had a slightly lavender tinge to it. It was a minor improvement over the original grey interconnects. It was the bees knees until the HiLine was introduced, and generally sought after by us Naim faithful. One only needed to buy one from one's dealer.
There was also ARO tonearm cable. This used to be available from select dealers in sexed pairs (ie matched direction), and was a COAX. It was absolutely *the sh*t* for connecting non-DIN components to your Naim, using a phono-to-DIN cable. The trick was it took a lot of patience to terminate the cable, stripping back the very tightly woven copper screen. I know, I built a tape solution cable. Masochist. I recall Tony's description as "gets out of the way of the signal, doesn't balls it up. Most neutral cable".
Hope that helps.