Need help with dating Dunlavy SC4's

@mark200mph  Thanks for your post!  I did not know that John made stuff for the military, although it does not surprise me. His design mentality would work well for military specs. You sure have your hands full with the 5's and the 6's. Glad you are still enjoying them, as I am with my 3's.

@pryso   Again, can't thank you enough for all of the in-depth information. I appreciate the time that you spent putting that little bio together.  I just bought a pair of modified SC4's, whose serial numbers I am exploring (the seller didn't remember the model year). 

Just a little back history of my discovery of the Dunlavy line: I was shopping for some new speakers at a shop called The Audio Den, on Long Island, ny (1998).  I came across a pair of SC3's, demos, and asked to hear them.  They put on an ECM cd of a European guitarist that I had known of but hadn't kept up to date on his releases.  The guitarist was Terje Rypdal, the cd was titled, If Mountains could sing, produced by Manfred Eicher, the song title: The return of Per Ulv. After the first few seconds, my jaw practically dropped to the floor: the air, the depth, the tightness, the speed, the articulation, and the sense of breath and clarity throughout the frequency spectrum just knocked me out.  And the snare drum was so crisp and clear with a hint of reverb that made it sound from outer space.  I bought them on the spot and still have them to this day. The new 4's are in my main system, the 3's in my lower man cave system.

A couple of years later my left tweeter began to intermittently buzz.  My experience with customer service at the time, probably 3 years before the shut down, 2 years before they were sold, was in step with their product: stellar.  At the time a man named Andrew Rigby took care of me in the usual Dunlavy quality level fashion.  He did not send me just one tweeter replacement, but a matched pair!!! That could be one of the reasons they went out of business, not sure.  Turned out it was a sticky voice coil.

Very sorry for this long-winded reply.  But since you were/are such a fan of the line, and you even talked to John himself, I thought that maybe you'd be interested in my little history being introduced to the line.

Thanks again for all of your info!!!

Well, that was off the top of my head, no research required.  Now a couple more thoughts came to mind.

John played acoustic bass so had the ear for and interest in the foundational elements in music.  So even his smallest speakers were not bass shy.

As Mark mentioned, his crossovers were first order.  That is not necessarily a preference by many designers but so far as I understand it, necessary to maintain the time and phase coherence John felt was essential.  As a matter of fact, few speakers are designed for that.  But Vandersteen's are and Thiels were, two other brands with musical quality reputations.

Since the matched DAL sourced drivers are no longer available, I can recommend Millersound in MD.  Bill LeGall is a very competent tech and has worked on Duntech and DAL speakers.

Also there was a dealer or individual in Iowa who was repairing and selling Dunlavy's speakers a few years ago but I don't remember the name or know if they might still be in business.  Maybe someone seeing this will know.

I’d love to find a pair of SCII speakers.