In article , Rob
wrote:
Jim Lesurf wrote:


The problem is that although there are many, many such "reviews and
anecdotes", there seems to be a dearth of any reliable evidence to
support such claims in many cases.

[snip]


Yes, you're quite right of course. The problem for mugs like me is
trying to figure out what, exactly, matters when buying a SS amp.

Yes. Alas, the root of the problem is that the 'reviewer' may be so eager
to fill the 'review' with his opinions (for which he may have no reliable
evidence, or apply in his situation but not yours) that he may simply not
bother to provide some simpler info that would help you make such
decisions. Readers are then left to 'guess' or simply take the opinions of
the review as if they were a guide...


The '3X' rule seemed to make a certain amount of sense at the time, so I
banked that as 'significant variable'.

For someone *making* power amplifiers it may make sense to design the amp
to be able to deliver high load currents and maintain its voltage output
into 'low loads'. This is because the designer/maker don't know what
speakers all the customers will be using, so have to cater for a range.

But for the *user* if they had the relevant information about their
speakers, and the amp, they could decide how relevant this would be for
them. Alas, the reviews or manufacturer info may not tell you...

I'm not sure any domestic amp at less than house prices actually does
this 3X thing.

You can get quite close to it - provided you have a good power supply and
output devices able to deliver high currents. Also larger heatsinks if the
demand is to be more than for brief peaks. Alas, this means that all
customers have to pay for these things even if only some of them require
them in reality. Hence the temptation for makers to shave away any
'overkill' which most users may never actually require.

[snip]

I have to say I'm pretty sure I can hear differences between amplifiers
that should sound the same, particularly at louder volumes. Thing is, if
I can - and I'm not taking that as a given! - why?

Can't say without much more in the way of specific information. There are
various possible reasons, but without a lot of details I couldn't say if
any of them are relevant. Speculation without data may simply confuse the
issue.

Slainte,

Jim

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