"A. D'A." wrote in message
om
Hi,

I wanted to borrow some of your knowledge/experience. I'm looking at
some proamp options for a multiamped hometheater system. One of the
amps I will require is for a set of 72" ribbons that measure cleanly
at 6 ohms; i.e. no dips, basically a resistive load. Accordingly in
this area I'm looking for an amp that is very clean in frequency
response and stable down to 4 ohms. One amp I'm looking at (because
it can be had cheap) is a Samson F1200. It can be found really cheap
in the used market, it is rated to down to 4 ohms and will produce
400/ch at 8 ohms (about the power range I'm looking for).

A pro amp that is rated down to 4 ohms is a bit of a lightweight. *Real* pro
amps have 2 ohm ratings. Seriously.

However, ribbons are generally thought to be pretty easy loads, in that they
are as you say often mostly resistive, and its highly reactive loads that
give cheap amps audible tummy-aches. 6 ohms should be no sweat. The gotcha
with ribbons is usually the need for lots of power. They are a relatively
inefficient lot it is hard to get lots of turns in a strong magnetic field
with a ribbon design.

Now, even
though I'm looking for cheap, this should not be construed as my not
being willing to pay what is required for a good amp. I just do not
feel the need to pay _more_ than more needs require in this area. Now
the ribbon is crossed over to a line array of Seas drivers at 225 Hz,
so needless to state the amp will be dealing with most of the midrange
and all of the treble.

Last time I heard a pro amp doing a credible job of driving ribbons, it was
a QSC USA 1300.

I will not sacrifice these areas for the sake
of saving money, but then again, I don't intend to throw money away.

Try eBay. USA 850s and 900s are the most common "find", usually closing
around $200. Will 375 wpc or so do the job for you? How much does it take to
damage that ribbon? It would be good to not be able to go there.