The tiny speaker the R75 has can't sound very good. If you are going to
spend the money for those modifications then spend a little more and buy
an external speaker.

I'll agree with this point. I am a mostly-nighttime (bedroom) SWL and as such,
I use headphones exclusively, regardless of which radio(s) I'm playing with on
any given night. But, the few times I have used my R75 without phones, I
immediately set up external speakers with some EQ to get it to sound full
enough to seem 'real'... and this even after I had all modifications and
enhancements done (mostly by me, including installing Kiwa's synch upgrade,
which I simply bought from them and installed myself)... the R75's a fine radio
with phones, or with decent outboard speakers. But the tiny, front-firing stock
speaker isn't full enough to do the rest of the radio justice.
Linus