[R-390] R-392 v. R-390

[Barry Hauser]

 Joe wrote (>)

> Isn't theFair Radio price for the R-392s ($550) about what they charged 
> for  R-390As before they ran out of them?

 About $550-600 for the last of the R-390A's as I recall.  Probably just a
coincidence.  The increasing price of the R-390A's reflected the amount of
 work and module-swapping they had to do, as well as refinishing the front
 panels.  As for the R-392's, probably more to do with limited supply as 
well
 as some prep./repair.


> How would you folks compare the R-392 to the R-390A or R-390 (non A) in 
> terms of value, performance, reliability and ease of repair?

 Josh Rovero has some web pages on this -- including a direct comparison.
 When fully tuned up, the the R-392 performs pretty closely on par with the
 '390's, within some built-in limitations -- namely just 3 bandwidth
 settings.  I've had several '392's and actually took the time to do a full
 alignment on one or two of them.  Although they seemed to work OK
 beforehand, what wound up as a touchup alignment made quite a difference.
 Here's the link to Josh's page
 http://www.roveroresearch.com/r392/r392_3.html


> I have an R-392 and an R-390 (non A). In terms of audio, it's no contest. 
> The R-390 wins hands-down. However, in terms of sensitivity and 
> selectivity, they seem awfully close. Both are impressive performers.

 What speaker were you using?  If you were using an LS-166 with the R-392,
 that's probably the main reason.  Because they are the correct speaker and
 have the U-77 ? plug and are "plug & play", that tends to be the speaker
 that's used.  However, the LS-166 is a voice frequency unit and
 water/concussion resistant.  It is basically an acoustic suspension box, 
but
 designed with no regard for the parameters necessary for fidelity.
 Generally, speakers have to be either ported (i.e. bass reflex, or open
 back) or sealed to deal with the back wave.  Of necessity, the LS-166 is
 sealed, but the volume of air behind it is too small and acoustic 
suspension
 designs call for high compliance cones and spiders (the corrugated thing
 around the voice coil).  The driver in the LS-166 is very stiff and motion
 is further restricted by additional screens both in front of and behind the
 cone. (blast & water pressure protection)   Some say that the small
 cylindrical matching transformer also has something to do with it.  If you
 are using an LS-166, try another speaker with a separate 600-8 ohm
 transformer, or just try running it with the back cover removed.

 If you don't mind a small modification, you can mount a mini phono plug in
 the side or back of the LS-166 and wire it so that when an external speaker
 is plugged in, it disconnects the internal one.  If you want to use a set 
of
 amplified computer speakers, you can tap off ahead of the transformer (600
 ohms) and eliminate that from the chain.  You can also pick up one of those
 connectors (Fair Radio has cut-offs) and wire up a dedicated computer
 speaker setup.

 Barry