A Second Opinion on the Ariels
Karna and I both enjoy listening to the Ariels, and so do our guests from the wild. Squirrels and birds sometimes drop by when I have the porch door open, spend a few minutes listening to the music, and depart off when the piece is over. One time the resident squirrel joined in with a ten-minute duet! Aside from these notes from nature, though, I haven't had a clear idea how human beings (particularly those of the audiophile persuasion) reacted to the Ariels.
So when Phillip Griffin, General Manager of The Parts Connection in Canada, called me out of the blue and said he had gone ahead and built the Ariels, I was naturally curious about the outcome. When you write an article in a magazine, it's like throwing a bottle in the ocean - there's no way of telling where it will go, or who will be the first to pick it up. It was a pleasant surprise to meet Phil on the phone and hear that the Ariels had gone well for him. That was a year ago; every now and then, I get a phone call from another PF reader who tells me about their experiences building the Ariels or the ME2.
A few weeks ago, some questions popped up on the Joelist (an Internet mailing-list for ultra-fi audio), and Phil jumped in and said good things about the Ariels. I'm not shy about asking for small favors, so I asked Phil if he'd mind writing a few short paragraphs for the book describing his experiences. A week later the following e-mail letter appeared in my computer:
To: Lynn Olson
From: Phil Griffin
A couple of years ago, I was in a bit of a quandary as to what to do with my system. I had recently moved to a small loft apartment, with a small living/listening room of a mere 11' x 14'. I was also getting more interested in lower powered, (<20W) simple circuit topology tube amps, and while I was enjoying what I was hearing from these designs, it just wasn't enough power for the Spica Angelus that I was using at the time. So, I needed a more efficient speaker, but didn't have the room for horns or Lowthers or anything else that had the requisite sensitivity. (Besides, I was getting enough grief over the presence the Spicas had in my diminutive room.)
But, what's this I see in Positive Feedback Vol. 4 No. 4-5? A 92dB sensitivity speaker that only takes up 8" x 11.5" of floor space? Has a flat impedance curve? Won't cost a fortune to build? Has reasonably extended bass response? A design that actually seemed to make sense? Well, it seemed too good to be true, but I thought I'd build it anyway. Luckily for my natural procrastination in projects like this, I hadn't started the cabinets before Lynn's next design article in PF with the labyrinth transmission line. (Lesson: Never build anything from a magazine article until the next issue is out with the revisions!)
With Lynn's article in hand, along with some AutoCAD drawings for the panels that I did, off I went to my cabinet maker friend's place to try to browbeat him into building a pair of cabinets for me. After a look at the plans, lots of cussing, and the suitable bribes (Canadians will agree to almost anything after a few beers!) he agreed to build a pair for me. The cabinets went together with surprisingly little fuss, even though this is a MUCH more complicated woodworking project than your average reflex box with a brace or two. I hereby reinforce Lynn's assertion that accurate cuts are essential.
My prototype crossovers were professionally assembled on a slab of MDF, drivers were installed, and the whole works connected up with alligator clips and jumper wires! Time to listen! WOW! I was very impressed right from the start, the Ariels had more extended, controlled, articulate bass than the Spica Angelus, imaging at least on par, a much more extended, airy, detailed treble, and a sense of dynamics and leading edge attack that I had only previously heard from horns! We were on to something here! (The Spicas were only heard once after that, when their new owner came to audition them!) After a couple of months of break-in and tweaking, the Ariels proved to be all that they seemed, with solid bass down to about 45Hz in-room, an exceptionally dynamic and tuneful presentation (that rhythm and pace thing if you prefer), excellent imaging capabilities, and a slightly warm tonal balance that makes for fatigue-free long listening sessions.
The Ariels' bass performance is quite sensitive to the stuffing in the line and labyrinth, and some experimentation may be necessary to get the best bass in your room. The adjustable height line exit is also of great help in tuning the speaker and gives more flexibility in room placement. Small changes can be quite noticeable, so proceed slowly.
Crossover component changes are also quite noticeable. Rest assured that premium quality parts are not lost on this speaker. After a few months of experimentation, I ended up with something very close to Lynn's Version 2.2 crossover. (Much to my surprise when he mailed me the schematic!)
I ended up using the Hovland MusiCaps in all critical areas, with Solen's in the impedance compensation network on the woofers, SOLO Copper Foil Air Core inductors, and Caddock MP series metal foil resistors. The premium quality parts simply added to the Ariels' natural sense of ease, dynamics, and improved resolution of low-level detail without ever sounding etched or analytical. I also used 0.1uF Teflon by-pass caps on the series tweeter caps that gave a slight increase in "air" and apparent upper frequency extension.
While I didn't experiment extensively with speaker cables, I did get excellent results using Goertz MI2 bi-wired from amp to crossovers, MI2 as continuous pieces from internal crossover wiring to the speaker inputs, and MI1 as internal speaker wire. The Goertz seemed to work so much better than anything else that I tried, I just didn't pursue it any further.
The Ariels also seem to love low-powered tube amplifiers. With their very flat impedance curve, high output Z amps are simply a non-issue with the Ariels. Most of my listening and "voicing" of the speaker was performed with a triode wired push-pull EL-34 amp of about 25 watts. (Modified Sonic Frontiers SFS-40) This provided plenty of power in my smaller room, even full-range. A triode wired, modded Dyna ST-70 also provided very pleasing results, proving you don't have to spend megabucks on amplification to get very enjoyable music out of the Ariels. I even tried a stock Dyna SCA-35 integrated just for kicks, and the Ariels still never failed to please, just not quite as much so. Excellent results were also obtained with a pair of vintage rebuilt Quad II amps.
A few listening sessions with a DIY SE 300B amp provided a gloriously large soundstage, with images extending well beyond the speakers, but not enough punch and control in the bass. I bi-amped this setup using a cap at the 300B amp input to roll off at 80 Hz (6dB/octave), a third order (18dB/octave) active low pass crossover at 75 Hz, a pair of Audio Concepts DIY 10" downfiring subwoofers, and a Hafler DH-200 amp (or whatever else I could borrow). This was a system that was very easy to live with, with open, liquid, and detailed mids and highs and a powerful bass flat to almost 20 Hz.
This setup also played VERY loud without any sense of strain. I measured approx. 110dB peaks cleanly reproduced in the listening room. This is WAY louder than I ever listen for any period of time, and unless you are a true volume freak, should be plenty for all but the largest listening rooms. It's surprising how far 8-9 watts per side can go when you use a powered sub of some kind. I continued to play with the subs after going back to my push-pull amps, but at least with the Audio Concepts subs, I had to keep the crossover point below 100Hz as a maximum, otherwise there was an audible discontinuity between the Ariels and the subs, no matter what their position.
A pair of forward firing, "fast" sounding subs, possibly sealed or transmission-line loaded, placed close to the Ariels may allow a higher crossover point and greater volume potential. For me, I'm more than satisfied with them, even full range, in my smallish room. I've had the Ariels now for over a year and a half, and am not even beginning to tire of them. I even broke down and built ANOTHER pair of cabinets, but these are actually finished instead of plain MDF! (Thanks to my partner Madelaine, who actually finished them for me in a beautiful "Marbleized" blue glaze finish!) A friend is now finishing my first pair for himself, and my cabinet making friend has built a pair for himself as well.
My audiophile friends have been very impressed with the Ariels, but that's not the real test. When our normal, um, I mean, non-audiophile, friends drop over for the first time, they almost never fail to comment on how good the music sounds even before they make it into the living room. To me, that's passing the ultimate blind listening test with flying colours!