Recommend a Pass Labs amp for Dunlavy SCIVa

Look for an amp having high damping ratio specs.

The Mac MC60 amp has a damping ratio of 12. The HK Citation II amp has a damping ratio of 18. These damping ratio specs are typical of tube amps.

The Pass amps have far better damping ratio specs, being 150 or above.

I used a Spectron Audio Digital One amp to drive my Dunlavy SCIVa’s. John Ulrick of Spectron Audio told me John Dunlavy voiced his SCIVa’s and others in his lineup with Spectron Audio amps (among others). Those amps typically have a damping ratio of 500.

If John Dunlavy used Spectron amps for his development evaluations then I'd be surprised.  That's not to say it didn't happen, just surprising if it did.

I owned Duntech Princess speakers for 19 years.  They were the older sibling to the DAL SC4 and 4a.  I enjoyed a few discussions with John at CES demos.  He did like some tubes as he utilized ARC electronics for  demos.  I know he also admired Adcom as an example of performance per dollar.  He revealed he was trying Adcom modules in development of a tri-amped self-powered model.

I experimented with several different amps over my time with the Princesses.  Toward the end of that ownership I found my best choice, the Parasound JC-1 monos.  From what I've read, the DAL models may have been more efficient than their comparable Duntech siblings, but I would still look for something close to at least 200 wpc with Pass.  Dynamics can be startling but you need current to realize that.

Another great choice. Parasound JC1 amps have a damping factor of >1200 (@ 20Hz).

I do have a crown studio reference II that has a dampening factor of 20,000.  Never considered it because it is not a real soothing amp.  It has raw power and I have used on home theater subs in the past.  This amp is monster for power and it will control any driver you hook to it

The amp I am really looking at in the used market is the pass X250.8.  I'm short a little cash and really wanted to only spend 3k but you get what you pay for