NAC 112 Volume Control

[robboss]

Greetings all–

I’ve made my way down the rabbit hole via the Naim Forum, Google searches and Acoustica, to ask you about a topic I several of you’ve dealt with before:

I have a Naim NAC 112 preamp. The volume started to go up and down randomly, and shortly after that, the remote control stopped working on the volume. My search revealed there is an IC chip related to volume balancing between all the inputs that frequently malfunctioned and Naim eventually discontinued that feature. Also mentioned on those message boards was the volume pot tended to fail in the 112.

My questions:

1. Do you know where I can get a schematic diagram for the preamp?
2. What is this IC chip of which they speak?
3. Is the Alps Blue Beauty Motorized a suitable volume pot replacement?
4. Where can I purchase them?

Thank you very much for you time and your help. Do have a lovely day,

Rob Boss
Portland, Oregon
USA

[Richard.Dane]

Rob, it’s going back many years, but early NAC112s and NAIT 5s used a TI encoder pot working with a resistor ladder network on the main board. IIRC, it appeared that when they moved production overseas, something changed and the encoders became rather flaky, many failing after a period of time. That’s why Naim changed to the ON encoder pot in production (with other necessary changes to accommodate) and any faulty units were updated as such at the factory.

You should contact the local distributor, Focal Naim America, for further details.

[JimDog]

I had a 112X from new and the remote broke after many years.
Then the volume control motor started making crunchy noises, although it still worked ok.

[Richard.Dane]

Jimdog, that’s unusual with the NAC112x as it used the ON encoder and was comparatively very reliable. FWIW, the earliest TI encoders were fine too.

[JimDog]

This was after over 15 years of continual use without a service.

But, yes, it was probably just bad luck.

[robboss]

Thanks for the help. It’ll help me get further down the road!