Infinity RS 1B - How does the 'old dream speaker' compare to today's speakers?

I'm with @cleeds I own and enjoy my IRS Beta.  Been around many other great speakers and only kept my Beta and on my secondary system my Aerial 8b.

Replaced the Solen caps all else is in-spec! on the crossovers.

as an experiment I am getting spare EMIM's rebuilt with very modern diaphragms (not current copies of the originals).

I have purchased AVA replacement diaphragms just in case for the future and to sponsor AVA's dedication to the brand.

What replacement diaphragm are you using

bdp24

... Infinity's were not built to high end standards.

Hmmmm, I bought my IRS Beta system around 1990 and it has been in use since then. I've refoamed the woofers a few times and repaired the servo/xover controller once. I have some spare NOS EMIMs as well as some upgraded diaphragms from Apogee Acoustics but I've never installed them.

Since trading a set of RS-1Bs on the IRS Betas, almost my entire system has been upgraded - some components more than once. The system has sounded better with each upgrade.

Demos I hear at my local dealer always sound excellent, but they don't outclass the IRS Beta.

There are good reasons that so many people keep these old Infinity systems running.

I echo @cleeds 

I have had owners of very high end (and very expensive) modern speakers listen to my Betas and walked out in awe!

Mine are also with the original stock diaphragms, woofers refoamed and replaced the Solen caps on the crossovers.

Wish I knew how to check the tune of the Servo Controller.

"updated" EMIMs are incoming followed by updated LEMIMs.  I am saving the originals untouched.

Sounds like the IRS are still competing well with modern speakers. I would have guessed that they had fallen behind due to decades in material (and electronics) development).