Tri-amping 3.6R's; what amp for the ribbons?


I currently use a active bi-amp setup w/my 3.6R's. The pre-amp/crossover is a DEQX unit, into a pair of 1000ASP ICEPower amps for the bass panels, and a pair of Bel Canto REF500M's for the mid+ribbon. The crossover is at 200hz, 96db/octave. I'm thinking about moving to a tri-amp setup. Anyone tried this with 3.6R's? Any advice?

What amp for the ribbon, assuming I keep the current amps for the bass & mid? I'm thinking a nice Class A tube amp for the ribbons, but that's just my first instinct.

BTW, I like to crank these speakers LOUD -- as loud as you can go before the panels start farting. I guess ribbons don't require much power, but how low can I go?

Also, I'm concerned about blowing a ribbon -- I have to bypass the fuses, right?
mikeand1

Showing 1 response by lissnr

Hello, Thought I'd throw in my 2 cents as I have a somewhat similar type arrangement. I too run dipole radiating panels and am "multi-amping" my speakers but in a slightly different way. Your 3.6's are great speakers (my first 'hi end' speakers were Maggie MG2B's over 30 yrs ago and afterward I was very happy with MG 3A's for many years). Yours are true 3 ways while my current planars are 2 ways (Apogee Duetta Sigs) which have a separate bass panel and a combined mid/tweeter ribbon. Your crossover scene allows true tri-amping which is very cool. I have what might be deemed "semi-tri-amping" wherein I use an external active crossover (an NHT X-2)to split my main signal at 50hz into a Rel sub, the remaining signal (call it 51hz+) feeds into another active crossover (a fully upgraded Apogee Dax 1) which then splits it into dedicated woofer panel tubed monoblocs (Conrad Johnson Premier 12's) and then to a dedicated amp for the combination mid/tweeter ribbon... This is essentially the equivalent of what you are describing you would like to try. Before I decided to run the mid/tweeter amp I had been using the CJ's and the X2 only, and after the sub relieved the bottom 50hz the CJ's did a great job...(this was utilizing the passive crossovers built into the speakers). Pretty simple, pretty direct...minimum complications and a very very nice sound. BUT, apparently like you, I just couldn't get the upgrade itch out of my mind so when this dedicated external crossover became available I thought I'd take the plunge and pursue the world of TRUE bi-amping...
The story is too long from here so I'll cut to the chase: after a LOT of pondering I knew I wanted tubes (that was never a question) but I also knew I wanted maximum flexibility and of course superb sound. Years ago I ran a pair of VTL MB-125 monos (into Silverline Sonata 2's = awesome combo) and since then became very enamored of the EL-34 tube... simply glorious midrange and a top that can extend as beautifully as the best out there, (especially when driving true ribbon tweeters as both you and I are). I've also appreciated the allure of running them in triode for certain types of music as well as some late night listening sessions but only as an option...full pentode or ultralinear is mandatory of course too. (The VTL allowed switching albeit NOT on the fly) and it was a nice feature.
What I eventually sought out for my application was an amp that could not only meet all of my requirements but in addition, was actually tube-TYPE flexible in case I felt the need to match the 6550's or KT-88's which the CJ's are using driving the bass panels. My answer finally became clear...an amp I had heard about 10 years ago at a dealership; it's a Cary, model SA 280 V12...(mine is an "i"model, F1 edition but that's not the point). It will run EL-34's, 6550's, KT-88's, and a few others as well...all at 100wpc ultralinear OR 50wpc triode as well as varying degrees of 1/3, 2/3 partial triode mix, and all capable of switching on the fly....And it sounds absolutely phenomenal doing dedicated midrange / tweeter duty...I think it would be well worth your while looking into this amp for your application. I will not attest to understanding the math of system/amp synergy in your rig, you will have to do your due-diligence to be sure the specs match up to the rest of your equipment but assuming that all can coincide together, I'm quite confident you will not be disappointed with its virtues...These include but are not limited to its spectacular soundstage, both wide and deep...complete lack of grain, tremendous sense of presence, air and natural timbres... a glorious sounding amp...
I really didn't plan on doing a review here (and I have no association with any brands/dealers/business in the audio field)...I'm just another A'gon addicted Lissnr...
Hope this expands your list of considerations by at least one more...but regardless of this particular amp or not, I would still pursue tubes to handle that tweeter of yours...remember: ribbons (especially midranges and tweeters) + tubes are pure listening bliss.
Good luck and happy Lissn'n