This thread is bound to stir a rousing debate.
The idea is to talk about subjective experiences rather than tech hype.(but please lets keep the flaming to Pms is there has to be any)
I'll start,
Like many I always thought chips or opamps were just that, an accepted part of modern electronics.
About 10 years ago I opened up my Phase Linear 3300 Series 11 pre amp and found a bunch of chips, NE5532 in the phono stage and output buffer and TL072 in the tone controls.
At the time I was a diy convenor at the local audio club so one afternoon we swapped in and out different chips.
After many swaps I concluded yes it did change the voicing of the pre amp but they were all just different.
None better or worse, and it was a case of blending associated equipment for the most pleasing result.
I then did similar things with a DAC and had the same experience.
A friend then bought over a Parts Connection Pre kit he built This was a discrete opamp affair, a simple Jfet diff pair and souce follower baised into class A.
We plugged it in. The difference was an obvious improvement, more fine details, for bass clarity, better imaging and a purity which I never thought possible.
In comparion both my consumer Phase Linear pre amp and Harman Kardan control preamp (5532) sounded flat, etched and thin.
I have since binned both to the Lab scap heap and use a discrete opamp preamp.
An audio engineer was over the other night for a look at the bad boys. The comment was "those slots and horn are very impressive. They are obviously that accurate that inferior electronics spoil their performance".
Ian