Would Jadis Orchestra work for Dunlavy IV?

Work for Dunlavy IV should read 'with' :)

It might work, but if you use EL34s instead of KT88s, 6550s or KT90s, you probably won't have the bass control you want. I used Jadis JA-80s (50-60 watts) on Duntech Princesses (pretty much the same speaker as the SC-IV) for years and gave up a bit of bass control for the glorious midrange, and it filled up an 18 by 20 room pretty easily. A DA-60 would be similar to the 80s in terms of power and might be a slightly better match than the Orchestra. I also am of the view that the Dunlavy designs sound better with tubes, so I think you might like the sound you get. The best sound I ever heard with Dunlavy SC-Vs (admittedly on material without a lot of deep bass) was with a VAC Renaissance 30-30 amp, so they can be driven with that power, you'll just not be able to listen at head-banging levels.

Thanks Rcprince. The other alternative is to go with Cary Integrated. Starting with 300SEI and may be up to SLI80.

I own a pair of SC-III's and have been very impressed driving them with a PrimaLuna Prologue 1. It's rated at 35wpc using EL34s. Before it I was using a Krell integrated with 150wpc. The PL is a significant improvement. Although I did lose a very small amount of bass slam, overall there is much more bass. I'd give the Jadis a try you just might be surprised with the result.

As much as I like the Cary products, the Jadis is a different league in terms of refinement, in my opinion. If you've heard the Jadis midrange you'll know what I'm talking about--there's a naturalness to the Jadis electronics that is very rarely heard. SC-IIIs might be a better match for the lower powered integrated, as they don't have the lowest bass that puts more demands on the amp, but I still think that it will work with your IVs as well, just don't expect bass "slam" or particularly tight, well-controlled bass (it will be full, though), especially if you use EL-34s.