With hindsight, this was an
ambitious project and took far longer than I
originally expected. It was a huge amount of work
for one person to design, build and test, a lot of
small setbacks on the way - my original estimate of
several weeks turned into many months. The reason I
agreed to take the project on was for the experience
it offered, for that alone it was worth it. I don't
mind admitting that perhaps I was a bit naive to
think that I could have these completely rebuilt and
installed in new cases complete with tone controls
and a full pre-amp section within the space of a few
weeks - in reality it took me far longer to make it
all work well and solve all the small problems but I
got there in the end.
The main complications came not from
the actual circuitry or the work needed to create
the different parts, but from the way the amplifiers
were constructed. As you can see from the
photographs in the article, there was a great deal
of wiring and extra components which needed to be
added, although I was careful to think where each
part could be added in terms of the heat it would
produce or the noise it might create, it still
became almost impossible to work on it by the time
everything was installed inside the chassis.
For instance, after I had assembled
everything the first time decided to change one
capacitor in each phono stage and that meant 6 hours
work just taking everything apart again just to
change a component which would then take less than a
minute to solder in. This complexity added huge
amounts of time to what would otherwise have been
simple adjustments, the process of perhaps needing
to set aside several hours to change one small
simple component and for further testing because I
had needed to disturb major parts of wiring, created
a major headache.
Even after years of repairing and
even building equipment, a project like this does
teach you an important lesson - that the actual
process of designing and creating a product which
can be assembled and then worked on later with
relative ease isn't anywhere near as easy as it
sounds, you might start off with a clean sheet of
paper with everything placed in a logical order but
it might not end up so simple, and even some of the
worst designed products might have started out as
logical, well laid-out designs before they were
chopped and changed during the prototype stages.
This project wasn't designed for me
and I have to be honest, certain things really
weren't to my personal taste although I tried not to
let that fact get in the way of my work. But, I was
really surprised how good it actually looked once I
had finished the final few things and actually saw
it all completed for the first time. It's really one
of those things where photographs don't do it
justice, seeing all the lamps lit in a dim room and
seeing the VU meters dance around in time to the
sound is almost mesmerising. I was honestly
impressed when I first saw it all lit up and
working, even though I'd spent a huge amount of time
building it and had probably seen enough of it to
last me a lifetime.
Shown below, the end
result:
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