Dunlavy SC-IVa how best driven

I have been driving my B & W 801s with Northcreeks crossovers with Audio Reasearch Classic 150s upgraded with infinicaps. My preamp is an Audio Reseach Ref 2. Does the IVs require more power to sing? Thus far i've been quite pleased with the performance of my system, but after hearing the IVas driven by an x350 combined with a tube front end, I knew I had to upgrade the speakers.
Try a Classe CA-301/401 or new Bryston 7-B SST (mono's)or 14-B SST with either 801's or SC-1V/A's. Classe amplifiers are true, fully balanced circuit topology. Both amps sound great. Will sound spendid with top-notch tube pre's.
Give em a listen!

peter jasz
I don't think the 4s need a lot of power. I loved mine with a 30 watt Pass Aleph 3 amp. They are really versatile speakers amps wise.
I used ARC Classic 150s with my Duntech Princesses for years (John Dunlavy's design at Duntech that was the precursor of the SC-IV and IVA). Those amps had more than enough power for those speakers, and plenty of strength in the bass in particular. I think that they will work VERY well with the Dunlavys, don't replace them till you hear them with the speakers. My feeling has been that the Dunlavys really benefit from great tubed amplification more than the Duntechs, which had a warmer midrange; by using the Classic 150s you'd also get the benefit of solid state-like control and extension in the bass.
Ive also heard Duntech Princesses driven by the Classic 120,s great sound.
Jwin I ran my Dunlavy SC4a,s with a Pass x-350, But agree they sound much better with my Papworth Audio M200,s(240watt tube monos) Highly recommend tubes with Dunlavys. But I,m a tube man
You do not need a lot of power with the Dunlavy's - the Classic 150's are more than adequate. The SC-IVA's have a relatively high sensitivity (~91db) and a relatively stable impedance. Thus, they are conducive to the use of tubes. Indeed, after hearing the Dunlavy's with about a dozen different amps, the best amplifier for use with the SC-IVA's was, without a doubt, the BAT monoblocks (120w/ch).
I run my Dunlavys with a McCormack DNA2 Deluxe. Preamp is Pass X1. Hard to fault!
I am pleased that my Classic 150s will work well. I have loved these amps and the way their solid state front ends and 4 pair each of 6550C back ends provide the best of both worlds. I do have two more questions if you are kind enough to help out. It appears that the 4 ohm outputs should be used and with a room 16W x 17D x 11H what might the best placement be?
Thanks for your hel.
Since the impedence and sensitivity of the SC-IVAs and the Duntechs I had are quite similar, the 4-ohm taps should work fine with the Dunlavys (in fact, they were the best sounding taps on that amp in my view). As far as placement goes, your room is about the minimum size for those speakers. Dunlavys are nice in that you can place them closer to a back wall than many others and still get reasonably decent sound (you will lose some soundstage depth back there), but they do sound much better away from the back and sidewalls. You should try to set up the speakers so you're sitting about 8-10 feet away from them so the drivers can better integrate, then bring them out from the back wall as far as you can without pushing your listening seat too close to the back wall (which will give you more, maybe too much, bass); they can also be set quite far apart if you like without affecting the imaging (I had my Duntechs about 9 feet apart; I've heard a pair of SC-VIs which were 20 feet apart image like a pair of mini-monitors), just toe them in more and watch out for sidewall reflections. Dunlavy advises putting them along the long wall, but in your case there isn't that much of a difference. These are just general suggestions--while they weigh a lot, it does pay to experiment with the placement, and they can be moved with a little effort so long as you don't have the spikes on them. Good luck!
Spectron Musician II. 500WPC will make those Dunlavy's sing!! Drop me a email,, I may be able to help you match up your pair.
I have the Dunlavy SC-V(s) and am quite familiar with
the entire Dunlavy line. One thing for sure is that Dunlavy
speakers love high current designs. In fact, I believe the
deep clean bass potential with these speakers is unsurpassed. I have had terrific success using two ARC D200
amps vertically bi-amping the speakers. Great Northern
Sound Co. can do wonders throughout the system in terms of
cost effective modifications that will maximize system potential.
I had a friend drive a pair of IV's with a pair of B&K M200's. He then added a second pair of B&K M200's (all amps sent back to the factory for calibration). The differnece was startling. I know these speakers are 91 db efficent. I know these speakers don't vary much in impedance. I know the manufacturer claims 150 watts max. I know the manufacturer doesn't think bi-wiring or bi-amping helps these speakers. I also know what we heard. The soundstage became enormous particularly in height and depth. There was an effortless quality to micro and macro dynamics that was both staggering and elegant. Vocalist became more coherent and dare I say human. Why such a difference? I don't know. Maybe we wanted to hear the differnce? Maybe the amps were running in class A longer? I don't know. I do know that it happend consistently, time and time again, even in different rooms.
I have my Dunlavys 12ft. apart 3ft. from the side wall and 4ft. from the front. The soundstage is BIG.The best tweak is roomlenes.I also think the SC4a,s sound best truely bi wired.
Unsound, Who told you 150 watts max. Most speakers sound better the more power you feed them, there are exceptions of course. But Dunlavys certainly fall into this catagory.
Evo845 I believe the 150 watts max that I applied to the Dunlavy IV's came from Dunlavy's old web site. It was in context of recommended power not short term power capability. Yes the soundstage of the Dunlavys when set up right is huge. But my friend and I were not expecting this already huge soudstage to expand even more and with more dimensionality when doubling the amps/power from over 400 available watts to over 800 available watts per channel. The Dunlavy's don't necessiarlly seem to need a lot of power. But, obviously we agree, that the Dunlavys seem to enjoy the extra power. I only wish that we could have tried doing the same with amplifiers having a better "pedigree". BTW, the rest of the system included a CAL CD player, Sonic Frontiers Line 3, identical Wire World eclipse (balanced) interconnects and identical Wire World Polaris speaker cables.
The 150i Aloia's were my favorite choice. I settled on those after using Cary200's and Wolcott. The hardest thing is to set them up properly with that large of a speaker. If you don't have room for them to breathe you won' t be impressed.