Probably the best out there is the Weiss DS-1 - http://www.weiss.ch/ds1/ds1.html
It's pricy though.

The BSS DPR 402 might make a nice affordable choice - Heathmans uses it in their rooms and from what I've heard that comes out of there they definitely know what they're doing.

The TC Finalizer boxes have a decent de-ess function.
Orban and Drawmer (the MX-50) make analog boxes that might be worth checking out too.

If you have a DAW - on the plugin side you can either set a multiband comp with a single band in set for the ess band or get a dedicated de-essing plugin. Waves has one that works ok. Avoid the SPL one - it's pretty ineffective and inflexible. Really nice freeware VST choice is Digital Fishphones "Spitfish" - which if set right can actually be pretty nicely effective and fairly transparent - shortly after making this plug Magix hired the guy to write dsp code for Samplitude so even though the free thing might scare people off he does know what he is doing - (Dead Link Removed)

Best regards,
Steve Berson

The Maselec MPL -2 is an excellent limiter/de esser. widely used for vinyl.

Thank you all for the info -- truly appreciated.

7 years later... ; ) I think Steve B uses the Derresser from Empirical Labs now
Another to consider is the De-esser from SPL

WaltzMastering, post: 376189 wrote: 7 years later... ; ) I think Steve B uses the Derresser from Empirical Labs now
Another to consider is the De-esser from SPL

The de-esser from SPL was what I was thinking too but, TotalSonic, a few posts above said NOT to use it "Avoid the SPL one - it's pretty ineffective and inflexible" Have you used it Waltz?
I have a lot of SPL hardware here and its all top notch. I was considering that one myself some day.

Yes, I used to have one, and while there were not that many controls on it, it worked great.

I switched to itb de-essing a while back just for the fact that it is automatible, where the hardware is pretty much on/off.