"Jim Lesurf" wrote in message
...
In article , Andy Evans
wrote:
Contrary to what Stewart and others think, I've spent 35 years building
and tweaking hifi with one aim in mind - to make the hi-fi system sound
like live music. I didn't use measurements for this, I used my ears
since I've been a professional musician for most of my life.

Well, I've used both my ears *and* measurements. I find the measurements
to
have been very useful in helping to identify what to do when my ears
weren't happy. Saved me a lot of 'flailing about' and helped me to get an
understanding of what it happening.

As both an engineer and a musician, I like the above approach.
When I build something that sounds especially pleasing, or perhaps
not sop pleasing, I take it to the workshop to find out why:-)

Over the years, several interesting factors have come to light.
Extended bandwidth (DC to daylight:-) is not necessarily a prerequisite
for a good sounding amplifier.

As regards distortion, I have found that the amount of THD is not
so important as the distortion content - the way the THD is made up.
For example amplifiers with a small amount of 3rd harmonic sound
less pleasing than amplifiers with a larger amount of 2nd harmonic.

My main interest is in high quality valve amplifiers, which IMO
are much more of a challenge for a designer than SS
(I also happen to like the way valve amplifier can sound)

It is probably true that measurement is not the complete story, as
amplifiers
are designed to play music through loudspeakers, not reproduce sine waves
and spectral noise into oscilloscopes and spectrum analysers. But being
able
to see what is going on, does tell one a great deal, and points one in the
right
direction.

Iain