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Narrators: Stephæn & Pete Riggle
Posse actually involved in this project: Far more. See narrative.
Part One of Three
A dyslexic man walks into a bra … or how I got sucked into
another speaker building adventure with my friend, Pete.

Introduction by Pete Riggle: Over the past half dozen years Stephæn Harrell and I have drifted into an unhealthy relationship in which we reinforce each other’s audiophile involvement. You could say that we are partners in crime. Our first project together was a pair of speakers with Great Plains Audio 604 drivers. We called these Stephæn’s Dream Speakers. After two years of self flagellation with these wonderful speakers, we got them finely dialed in and subsequently became bored. We sought out another crime to commit. That crime against nature turned out to be the Po’ Boy speakers, which we constructed in 2008. Yes, basically it ate up most of the Saturdays and Wednesday evenings of 2008.


Stephæn advised me some time back that we were going to do a 6moons article on the Po’ Boys. I said "Uh huh," and we went back to work on the new criminal enterprise. A few weeks ago, Stephæn handed me a sheaf of papers advising me that we had written the article. I said "Huh?" The sheaf turned out to be a compilation of emails I had written to friends and mentors during construction of the Po’ Boys. The sheaf of papers included callouts for various images. The emails were interspersed with nuggets of wisdom in bold type provided by Stephæn. I liked the nuggets. It is surprising that the compilation of emails, images, and nuggets does indeed tell a pretty good story about what happened.
Signs on the Bad Boyz Benevolent Association clubhouse

Before moving to our email message log of the Po’ Boy journey, here is a little background. In the fall of 2006 Stephæn and I attended RMAF Denver. One evening we made our way up to the Cogent/Welborne room to hear a pair of all-horn loudspeakers.  These turned out to be a project of Rich Drysdale and Steve Schell, the folks behind the Cogent brand name of magnificent compression drivers. We heard a blues singer with a guitar and harmonica sensuously hanging in the dark space of the lowly lit room. The timber and dynamics were most appealing. Like all sonic phenomena, it was basically indescribable.  The difference is that this was—in the best sense—more indescribable. We were dazzled. Stephæn and I still talk about it.  What a fabulous sound. 


Later on, friend Ralph Henson who was also in the room when we heard the Cogent system, mentioned that the system was bi-amplified that evening (with Welborne tube amps) using DEQX, a well-respected digital crossover system that allows for digital time alignment. The drivers we were hearing were the Cogent field coil compression drivers which are modern devices inspired by the rare and wonderful RCA 1428 field coil theater compression drivers. 


Cogent makes a bass driver for use in a bass horn extending down to perhaps 60Hz; and a high-frequency driver for use in a midrange horn extending from 300Hz to above 10kHz. The Cogent drivers are expensive to manufacture. Gorgeous things. I believe I have heard a price of $60,000 for four drivers (two for bass, two for high frequency). About a year ago Rich advised me of a Recession Special Price.  It's not too clear in my memory but I think the RSP Rich quoted was $48,000*. The horns with J-shaped bass horns we heard that evening were built by Steve and Rich to Bill Woods' AH! 300 horn design using his cast aluminum throats, 12-petal conical horn concept and logos affixed to the horns (Acoustic Horn). The conical horn has much to recommend it and Bill can sell you these horns and accessories. I’ve heard Bill's horns and full systems and they are good, really good.



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* Correction from the Cogent folks: "Our list price for the drivers is $15.000/pr for the DS-1428 and $17.000/pr for the DS-1448. $60.000 was a show special asking price for the complete horn/driver system. Our current recession special price for a complete system would be about the same."
Jonathan Weiss , Steve Schell and Rich Drysdale in front of the Cogent-built speakers

In 2007 I arrived at RMAF on a mission which my brain had cooked up on the flight to Denver. What if Stephæn and I —way too much work and too boring for one person unassisted; and what is more fun than two friends wielding tools and alcoholic beverages—could build a poor man’s speaker system inspired by the Cogent vision using good (but not too good, financially speaking) drivers? The result came to be known as the Po’ Boys.


At RMAF 2007 I immediately headed for the Teres Audio room. Chris Brady, the Teres prime mover, had acquired from Cogent the pair of speakers Stephæn and I had heard in 2006 and had them up and running. With some reserve I hung at the back of the room hoping to find someone to talk with regarding the Po’ Boy idea. About that time I ran into friend Jay Fisher who expressed enthusiasm and buy-in for the Po’ Boy idea. He directed me to Jonathan Weiss of Oswaldsmill Audio. Jonathan went to a table at the back of the room and pulled out something I’d never seen before - an RCA 9584A Theater Driver, a veteran Alnico midrange compression driver used in movie theaters during the middle part of the last century. What a big heavy industrial-looking thing. The diaphragm was phenolic (this is important). Jonathan had collected quite a number of these drivers for use in the Oswaldsmill speakers he now offers for sale. Jonathan advised that these are excellent drivers, with a frequency range extending from 300Hz to above 7000Hz when coupled to the right horn. This is two thirds of the eight most important octaves.


Later I learned from Steve Schell and Bill Woods that if you cannot afford the Cogent field coil drivers—or the RCA 1428 field coil drivers (also from the last century) that inspired the Cogent drivers—the midrange driver to have is the RCA 9584A. Shortly after Jonathan had shown me the RCA 9584*, Jay came up with Steve Schell in tow. Besides being one of the two principals in Cogent, Steve is also one of three co-founders of the Lansing Heritage website. Steve is a walking encyclopedia of all things Lansing, Western Electric, Altec, RCA, theater sound and acoustic horns. Steve turned out to be extremely cordial and helpful. Steve consulted repeatedly and most graciously during the design of the Po’ Boys and has a friend Robert living in Australia who had in storage two pairs of the RCA 9854A Theater Drivers he was willing to sell to Jay and me. Now, on to the email log and nuggets of wisdom from Stephæn.

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* Addition from Cogent: The RCA MI-9584 driver came in A, B and C versions and all are similar and well suited to a project like this. The official name of the legendary RCA drivers built from 1937 to 1942 is MI-1428B (13VDC field coil) and MI-1443 (115VDC field coil). Aside from the field voltages they are identical.

Never miss a good chance to shut up.
March 6, 2008



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