A More Ambitious Upgrade - Part 4

The usual process is taking place, that is, as movement forward is made, the remaining inadequacies that were not readily noticeable earlier become more prominent, become easier to discern and easier to tie directly to some part of the whole. In my previous update I said I felt I was in good shape, but underlying that was the concern that the volume control, a cheap Alps potentiometer implemented in a very conventional way, would start to rear its ugly head - volume controls are a huge concern in audio, and my previous experiences are that all straight analogue methods are too great a degrading factor; hence, and luckily by accident, I have always used digital control or semiconductor circuitry to date - no raw switches or wiper on tracks used. With good results ...

Which brings me with dealing with the NAD amp. Its virtues have shone brightly enough so far, but a day or so ago an album which quite quickly developed a dirty, irksome edge to the sound got my attention. Was this the volume pot becoming too much a problem, finally? Yes, it was - a quick jiggle of the volume setting cleaned up the sound momentarily and then the unsavoury quality to the tone started to fairly quickly build up again. Bummer !!! Now that I can "hear it" I'll always be aware of its effect, unfortunately.

So, I'll have to bite the bullet! I've never done a major exercise of resolving potentiometer quality issues up to now, I've always been able to sidestep them - but this time my focus is different: I really want to get the best out of the gear without major re-engineering of parts of the components - a "simple" solution is to rip out the pot and install a full-blown, very high quality semiconductor or possibly discrete relays and resistors circuit. But this is an involved, relatively expensive approach - I won't go there until all low cost alternatives are explored.

This means that I'm now in full flight in investigating what the experiences of others are, what tweaks and tricks have been used - and will start trying the best ideas that I come across ...