[Scott Dorsey]

Matt Faunce wrote:
Why is there no gain control on the Adcom GFA-535?

Because you didn't order it with that option. If you want the level control,
you want the GFA-535L.

I've used it in between my computer (iMac) and my speakers, and controlling
the gain from the computer works, but there's always a noticeable hiss.
Wouldn't it be better to have the output of my computer much higher and
attenuate the output of the Adcom?

Yes, if you are stuck with a noisy interface, you may need to do that. You
might just be able to put a fixed attenuator in front, though, rather than
bother with a full gain control.

Similarly, I've seen many reviews of powered speakers where the reviewers
complain that there's a noticeable hiss that can't be attenuated. Why are
they designed like that?

Because the designers are expecting them to be used with sources where this
isn't a problem. Consider investing in the Behringer Monitor1 passive
attenuator or something similar if you're stuck having to structure gain
this way.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."