Brian,
The Advents that we listened to, I built for for Tom, who had heard my basic version. He really liked the waveguide on the Advents, but wanted a little bit more quality sonically. I lined the cabinet with No-Rez and built the crossover with Sonicaps and foil coil inductors. The crossover was mounted outboard in the speaker stands.
The finished speaker looks like this.
It uses a JBL waveguide with a Selenium DT220ti compression driver. The woofers are the standard New Larger Advents that had been refoamed. Internal wiring is my M-80.
I first built my waveguided Advents for a fun project. I had the cabinets for many years and thought I just might use them for occasional backyard parties. I was amazed at how well they sounded. I started researching the Wavguide concept and stumbled on information about Tom Danley and his Unity Horn. This was a waveguide that had a separate compresion driver for highs and cone midrange drivers both in the same horn. His current company now makes another unit called a Synergy Horn that also has 2) 12" drivers for low end.
Here is a .pdf of a white paper about some of Mr. Danley's designs for low end speakers and the Synergy Horn.
Yorkville Sound had licensed Mr. Danley's Unity concept and has produced a couple of speakers using a single compression driver for the highs and three cone mids all on the same horn.
The U15 mates the unit with a 15" low frequecy driver.
I was excited to find a fellow AC member that had a pair of these U15s and even lived in Denver.
I got in touch with dwk to see if I could audition the Unitys and it turned out he was in the process of redoing his listening room. He asked if I would be interested in borrowing his speakers for a week or so. HELL YES, I believe I said. Doug was kind enough to drive them out to me so I could listen to them in my system. I spent most of Halloween night listening to these and changing where they were in my room.
My first thought about these speakers were, and still are, DYNAMICS. At 98 dB@1W/1m they don't need much power to get going. At 127 max spl output they can keep going long after your have given up. During my time with the U15 in my system, I heard far more detail and emotion from my recordings. The high efficiency brought out subtleties that used to be buried in the mix. There was far more expression coming through Clapton's fingerings and Miles' breaths.
All is not perfect. There is some oddity going on in the mids. On some recordings everything sounds great. On others it seems something has gotten lost. On my VMPS it was very easy to tell differences between studios, lablel etc. The Unitys made all recordings sound very similar. I could hear more into the recording, but the overall tone was uniform.
I was very interested to compare the Yorkville speakers to the Geddes Abbey. They both use Pro Sound divers. They both have unique designs for mids/highs. They are both fairly efficient. I got in touch with Mike Galusha to see if he would be interested. He was and this get together progressed.
I also got in touch with Tom to see if he would be interested in bringing his waveguided Advents. Mine having been torn apart to mod a pair of Wharfedale W-60Ds for my daughter.
All of the above was to set the scene for our listening session this past weekend.
This was the first chance I had to hear Mike's Abbeys. I have read quite a great deal about Dr. Geddes designs and was very much looking forward to hearing them.
The Abbeys were played first and sounded great. Very nice dynamics. Good image. Slightly recessed high end. Mike uses three Rhythmic subs spaced about his listening room. They were tuned to the Abbeys. There was no adjustment to the subs during the listening sessions.
The next up were the Advents. At first the high end was dominant . I went up and adjusted the L-pad to lower the output of the compression drive. Everything was then balanced out. I have to say they were closer in sound to the Abbeys than different. They had the same "tone" and evenness through the mids and highs. The Advent woofer is nowhere near as efficient as the B&C used in the Geddes, so they were not as dynamic. They did play lower but did benefit when Mike turned the subs on. All in all, I would have to say they were the value leader.
They could not play as loud as the Abbeys, they were not as dynamic. They did play deeper bass. Considering that these were built using 30 year old cabinets and refoamed woofer from the '70s they did a fantastic job. Of course, seeing as I built them, I may be a tad biased
Next up were the Yorkvilles. My first thought on hearing them was again DYNAMICS. They were so much more effortless in reproducing micro and macro dynamics. Mike put on a vinyl recording of Billie Holiday: "Songs for Distingue Lovers". The kick drum was in the room. Unfortunately, the muted trumpet was not. The same disconnect in the mids happened in Mike's room.
We switched back to the Abbeys on the same recording. The kick drum was muffled. The trumpet was there.
I took some interesting observations away from this session. I have become addicted to the dynamics of high efficiency pro drivers. I do believe that whatever speakers I own next will be built using said drivers. I also have become a convert to compression drivers in a waveguide. Which drivers and what waveguide still are yet do be determined.
I was expecting to be very impressed with the Yorkville U15's interpretation of Mr. Danley's Unity driver. I was more impressed with the 18sounds woofer they used. I would very much like to hear a true Danley Sounds Synergy system.
For me, the foam plug mutes too much of the top end of the compression driver. Without it, the Geddes waveguide is very harsh. The JBL waveguide used in the Advent build has the clean top end without harshness without need for foam. The overall sound of the Geddes Abbey IS superior to that of the E-waved Advent, but the Advent gets very close for a lot less money.
Thanks to Mike and Mary Galusha for putting up with another influx of audio geeks with very large boxes coming into their house. Thanks to Tom and Doug for allowing us to listen to their speakers.
