A question that comes up frequently is:
Why do you need a 3.5 meter run of Naim NACA5 or AV Options Twisted-56 speaker cables with vintage Naim amps (Chrome Bumper and Olive)?
Most power amplifiers have inductors in the output stage to maintain stability (non-oscillation). The designer does not know what speaker wire type or length (and hence inductance) the owner will use with the amp. Optimum performance is therefore sacrificed for universality.
Vintage Naim amplifiers (Chrome Bumper and Olive era) do not have their performance compromised by using inductors in the output.
Naim prefer to use the speaker cable to provide the correct inductance and capacitance for output stability.
To do so:
1) a minimum of 3.5 metres of suitable speaker cable is required per channel. Naim NACA5 and our Twisted-56 speaker wires provide the correct load needed for stable and optimum performance of vintage Naim amplifier.
2) cables for left and right channels should be of exactly equal length, even if one speaker is closer to the power amplifier than the other. This ensures that both channels see the same load (inductance & capacitance) at the output, resulting in matched performance of both channels. High quality connectors and terminations are also necessary.
Naim NACA5 Pair (with optional Deep-Cryo treatment) - Naim Dual Plugs at amp end and Naim Banana Pins at speaker end
Naim amps and integrated amps post 2002 still don’t have output inductors but the output stages were redesigned to tolerate a marginally higher capacitance and lower inductance.
Excerpt from a later Naim amp manual:
"Loudspeaker cables are vitally important. They should each be at least 3.5 metres long and of equal length. The recommended maximum is normally 20 metres although longer cables may be viable with some Naim amplifiers.
Some Naim amplifiers [Olive gear and older] are designed only to work with Naim loudspeaker cable and using alternatives may degrade the performance or even damage the amplifier. Other Naim amplifiers can be used with any high quality loudspeaker cable although we recommend that Naim loudspeaker cable is used.”
Bottom line - It’s still bad to use high capacitance type wires or Audioquest star-quad “low inductance cables” for example.
The specs for Naim NACA5:
Capacitance (max): 16 pF / meter
Inductance (min): 1 uH / meter
Resistance: 9 milliohms / meter
NOTE: If using speaker cables other than NACA5 or AV Options Twisted-56 to be safe we recommend a range of +/- 5% at most from these specifications.
For post 2002 Naim amps/integrated amps we strongly recommend AV Options Twisted-56 Deep-Cryo speaker cable as the ergonomic (more flexible than NACA5) and cost effective solution that works superbly with all of these Naim products (and with Rega, Linn, etc, kit as well). Each Twisted-56 pair is made by Chris West in our AVO Workshop using only the highest quality connectors, solder and termination techniques. Deep-Cryo treatment by our long time vendor Cryogenics International.
AV Options Twisted-56 Deep-Cryo Pair with Naim Banana Pins