What's the difference between A4 and UOA5?

[freefrog]

Re: What's the difference between A4 and UOA5?

So to answer the question myself after trying both:

UOA5 don't reallu sound like A5's. They have more midrange, less bass and treble. Frequency-wise UOA5’s are situated halfway between A2 and A5, like a more midrange sounding A5 or a more modern sounding A2. Not mellow like A2, but rather hard sounding mids when gaining up with decent note definition.

A4 sounds different. Very defined, superb note separation, flat frequency response.

During some lab tests stored in my archives, UOA5 had also a sonic effect not noticed with ANY other AlNi(Co) alloy: when the coils were excited by a fixed testing signal, UOA5 was giving a noticeably slowest attack (while the speed of the attack with A4 was roughly the same than with A2: A4 changed the EQing compared to A2 by it was dynamically similar in this case; and with regular A5, the attack was the fastest).

FWIW.


SIDE NOTE - Some day I'll try to share the sum up of a comparative test done here a few years ago : a batch of AlNi(Co) bars had been systematically tried in a machine wound HB, a hand wound HB and a P90. Some results were expected while some others were somehow surprising... :-)

[Cdwillis]

Re: What's the difference between A4 and UOA5?

What do you mean by attack with the constant signal, freefrog? When I think of attack I think of the initial sound when something is picked.

[freefrog]

Re: What's the difference between A4 and UOA5?

What do you mean by attack with the constant signal, freefrog? When I think of attack I think of the initial sound when something is picked.

I was talking about impulse response tests. By "fixed testing signal", I was meaning that the electrical stimulus used for IR was always the same. Sorry if it sounded ambiguous :-)