DIY 2002 - Atlanta - discussion (1 Viewer)

[Patrick Sun]

FYI: Chris is talking about the Rolling Stones concert in Atlanta that night.

 

[Greg Monfort]

What a zoo/sonic nightmare that's going to be! I think I'll just drop some of their vinyl on the ol' TT. At least this way I'll still be able to ~understand the vocals when I crank it up.
GM

 

[Jay_H]

From Stephen H.


Dr. Leach offers, or at least did ca. 1997-8, a Special Projects class as well. At the time, it was good for 1 quarter-hour credit, I think. Basically, you design, build, and test a pair of speakers (or amps, etc.) under the watchful eye of a master. I was pretty amazed at the amount of time he spent on an ignoramus like me for a one hour class.

That was one of the two best classes I took at G-Tech during my year there. (I was an INTA for four quarters, during Joey Hamilton's heyday.) The other was on the history of industrial design. Come to think of it, that has decided DIY applications, too: there's no reason you couldn't write your paper about influences on loudspeaker (aesthetic) design....

See y'all on Saturday!

Peace,

Jay

 

[Jerry McNutt]

Hello,
We are going to the event in Dayton on Nov 2. We will have a pair of budget arrays called the "Firebirds", a pair of LABhorns, four Beta10CX pa cabs, and two Kilomax18's.
Here is a link to the Dayton event:
http://home.woh.rr.com/dakuzma/diy2002/dayton.htm
Thanks,
McJerry
Eminence Speaker LLC

 

[Patrick Sun]

FYI: The weather doesn't look too good for Saturday morning, so anyone bringing speakers might want to bring something to cover them while transporting them from vehicle to the 2 meeting rooms.

 

[Brian Bunge]

Pat,

I think I've got plenty of blankets! I'll be sure to bring one or two with me!

 

[Patrick Sun]

Just got back from DIY Atlanta, and there was some very impressive variety of speakers, ranging from small full-range speakers, to massive line arrays 7 feet tall. Once I get some sleep, photos will be forthcoming.

 

[Brian Bunge]

That's right folks! I was at the DIY Atlanta event today and can say with all certainty that Pat is a sellout!

Have any of you noticed that he hasn't been posting much lately? I knew something was up and today he confirmed my suspicions. He is no longer a member of the "Nekkid Speakers Club"! I sure hope he never registered that URL because he has no right to it any more! He has painted the baffles on his entire 5 channel system with green hammerite paint and have veneered the rest of the cabinets (well, I didn't look at the backs or bottoms) with red oak veneer! Now he's yet to apply a finish to the oak (or even sand it for that matter) but the fact is, that raw MDF is gone!

 

[ChristopherD]

Bold alegations.
Care to comment, Pat?

 

[Dan Hine]

Bold but true. What is the world coming to?

 

[Dustin B]

And the next question is where are the 100+ pics of the finishing process
The end is here, run for your lives

 

[Brian Bunge]

Dustin,
I assure you that Pat had camera in hand at all times! Even on trips to the bathroom it seems, no lie!
And since I forgot to mention it above, I really enjoyed meeting Dan, Chris Carswell, and Ronnie Ferrell! Ronnie did an awesome job veneering his A/V-1's, especially for a first timer! I wonder if it had anything to do with his instructor?

 

[Craig Woodhall]

hehe, you guys kill me..

 

[Pete Mazz]

Well, if this is true, he'll have to turn in his membership card and badge. I guess we'll have to come up with another secret handshake as well. Nekkid speaker builders across the globe are now officially in mourning.

Traiter!!!

Pete

 

[Patrick Sun]

Here's the DIY Atlanta 2002 Photo Album.

 

[Dan Hine]

As I already mentioned, I thoroughly enjoyed the event. But what made it even better was that after a few questions and some advice I finished my HE10.1's tonight. After just 10seconds of listening to them I love them. They will easily be replacing my Polk towers which retail for ~$1000/pair. Thanks to everyone who not only helped me but inspired me through their passion for speaker building and audio in general.

Oh, and thanks Pat for that shot of my backside.:b

 

[Chris Carswell]

Dan, I think every picture he got was of the back of our heads . I'm glad you got your HE10.1's finished & they sound good. Next meet you bring them & I'll bring my stuff
I would like to mention that it was quite nice meeting everyone, specially these guys: Brian Bell Bob Brines Jim Griffin Ken Perkins. Be careful, these few people I'm not so sure about: Dan Hine Brian Bunge Ronnie Ferrell Robert Cheng Pat Sun Greg Monfort........
Seriously though I had a great time & everyone was just super. Robert did a great job organizing this. I got a lot of good ideas as well as information. Also heard a ton of great sounding speakers. Some designs were really cool. I will say that Brian can really build some boxes folks. His work is top notch! I only hope we can do this again sometime, but don't know if I can wait another year. See ya all around.
-Chris

 

[Brian Bunge]

Chris,
Thanks for the kind words.:b I really enjoyed talking to all you guys! Even some punk kid going to the University of Florida like you! Good thing I'm not a college football fan!

Dan, I think every picture he got was of the back of our heads

I thought you asked him to get your good side?
BTW, I can't wait to get started on a pair of Jim's 1.5-way full rangers! I'll use the TB drivers that I currently have and probably have the MDF cut tomorrow!

 

[Jay_H]

(28.10.02 edit main edits include fixing detail errors, cleaning up some of the grammar and diction, expounding on the Tannoys, adding my preferences and ideas for next year.)
Here's an excerpt from something I'm writing for the Basslist about DIY2002 in the ATL. Enjoy, and correct me as needed.
Four massive columns greeted me as I walked into the door. They were two pairs of Linus Arrays. The Linus (designed by Jim Griffin and Rick Craig, see Mr Griffin’s white-paper at www.prism.gatech.edu/~gte929u/LinusWP.pdf) features a column of twelve 130mm aluminium woofers sourced from MCM (also used in the Bottlehead Straight-8) with six of the 6” rectangular flanged Stryke/Dayton/Hifisound planars nested next to them. The Linus’s were one set of speakers that I’ve been dying to hear. And how was the hearing? Well, they answered most of my questions but raised a few others. They have an effective radiating area of ~960cm^2 per side (roughly on par with twin Dynaudio 30W100’s) in the lows and ~175cm^2 up high (more than a ScanSpeak 8545!), they definitely had the ability to scale “energy density” passages (massed strings, for instance) properly. Also, I wasn’t bothered by their non-concentricity. Moving around, they sounded pretty much the same – and coherent, with little “Venetian blinding” – throughout that range. Images were larger than with point sources, but not appallingly so. Where did they lose out? They have two main flaws to me. The first is simply that they’re huge! What, you mean a line array with eighteen drive-units in it has some volume? For some reason, the width of them threw me off guard a bit. (See them at http://www.selahaudio.com/_uimages/LinusFront.jpg) Also, the tonal character changes markedly when going from seated to standing. The tweeters beam in a cylinder. At 6’1”, my ears are a little bit above that cylinder whilst standing. Mr Griffin (who at 6’3” is more above the treble than I) noted that his next array (drool, drool) would probably extend the tweeter line by ~6” in both directions. Yum. Also, the bottom-end seemed to lose a little bit of focus compared to the excellent mids and treble. The Leica-esque low end focus of the Tannoy D500’s that followed the Linus’s exacerbated the latter’s relative shortcomings in that area.
The Linus wasn’t the only project Mr Griffin brought. He also had his Jordan JX92S cabinets that won the DIY2001 competition, and a pair of 1.5-ways using twin TangBand paper-cone 3” woofers. Of his projects, the lattermost impressed me the least. Then again, they were by far the smallest and least expensive speakers I heard. Still, that little TB has potential. I could see an array of six making a stellar back or side surround channel. (I built surrounds with six of the old Audax HT080G0 driver once, with satisfying results.) I was never in a good spot to give the JX92S’s a fair audition (the Dreaded Show Conditions, the Stereophile writer buried deep in me wants to exclaim from the rooftops), but I suspect they sound as killer as they look. One set of listening had the Jordans combined with a sub by a marque I had never heard of, SVS. They seemed to be essentially a clone of the TN-series subs by Hsu Research. They definitely did the job, but were tuned to a bit higher Q than I would prefer for my own system. I left the room before it was replaced with a sealed sub.
Another speaker I quite enjoyed hearing were Brian Bunge’s GR-Research AV-1+’s. These are 130mm MTM’s with two of GR-Research’s proprietary Peerless India midwoofer, hand-matched TB tweet, and a parallel (corrected from original) crossover mating the three. They sounded great, with clear, holographic imaging, outstanding coherency, and excellent weight for their size in the midbass. I would also be remiss if I failed to mention the outstanding carpentry of these cabinets. They were seemingly wrapped with a single piece of veneer on four sides, with a separate piece for the top. They were also knuckle-damagingly solid.
I don’t in general have great affection for 6.5” 2-ways. Frankly, I’ve yet to find one at any price that betters KEF’s humble little Q15. They always seem to have annoying “horns” in the power response at crossover, and the limited surface-area of a single 180mm woofer compromises performance in the lower mids, even when relieved of deep bass duty by the sub. (The KEFs avoid the former shortcoming by virtue of concentric mounting, but the problem of scale – of making a large ensemble sound as big as it should – is a huge problem with them and all other small 2-ways.) But I did find one today that’s better than the little KEFs. Bob Brines brought a 2-way with the Peerless CSX woofer and the shallow horn-loaded Peerless tweeter that I think M&K used or perhaps still uses. The crossover, I believe, is of the series variety. So, the component cost is extraordinarily low for a speaker with seriously extraordinary resolution. The catch? A massive TL cabinet, designed with the help of Martin King’s spreadsheet. It was more relaxed in the upper bass than any driver that small has any right to be. It also delivered a very liquid midrange. Others complained about the treble in an early listening session, and there was a slight hardness to it when we listened to them (hooked up to the Marantz 8B glass amp), but I suspect it was much worse when hooked up to a sand amp. I might not have noticed it if I weren't listening for it. Maybe there’s something to this whole TL thing after all. His approach to flush-mounting added some flair to the large “tree trunk” cabinets, with a thin black panel the thickness of the woofer flanges mounted on top of most of the baffle. At lunch, several people
Another impressive (albeit expensive) TL was Brian Bell’s interpretation of the Seas Thor TL. The Thor is a kit that uses twin Seas W18 magnesium woofers and the Seas Millennium tweet. The woodwork on these things was 10,000 leagues over anything I would be able to do. And the sound? Quite nice. In the mids and treble, they were a clear as great headphones. It makes me understand why people rave about the Excel midwoofers. The drivers had very, very few hours on them, so I’ll reserve judgement about the bass. (Brian also had some Leach amps that he built – and seemingly boards for several more.)
Robert Cozine interpreted a design by Ric Grambo called the “Big GT”. The GT is an MTM composed of 200mm Audax polymer-basket HD-A woofers and a tweet, with a parallel crossover. The sound nicely tracked the size of the ensemble, with plenty of weight on the low end. In a small room, subs are almost optional. Several people mentioned that the tweeter was padded down a bit much, but I did not think that a problem. Rather, as I’ve noticed with many DIY speakers and most commercial ones, the tweeter is simply too low. Raising the speaker or tipping it back would just about perfectly take care of the problem.
(Observation: DIYers seem to be taller than the population at large, at least in the ATL. There were a bunch of participants 6’2” (~190cm) or taller. Perhaps that explains why tweeter heights for DIY speakers tend to be higher.)
And then there’s the Tannoys. I’d not yet heard these D500’s, although I was bowled over by their bigger brother the D700. They have an 8” dual concentric and another 8” woofer below that, and operate as a three-way rather than a 2.5 way. While these were to my ears the best speakers in attendance (with second place going to Mr Brines'TL and third a tie between the Linus and the Thors), they were also the most expensive by roughly 3x, with a high street price of ca. US$3000. That said, they do nothing wrong. They have amazing focus and precision in the penultimate octave (obviously an 8" woofer isn't going to go any lower), unparalleled top-to-bottom coherency, and generally just sounded GOOD. Even the cost, considering the cabinetry and engineering, is reasonable, at a little bit less per pair than a good suit costs.
Oh, how did my speakers fare? [hangs head in shame] I didn’t bring any. The main speakers I built in 1998 (Vifa M18 mated with first a D27, then a GR Research Tangband tweet, and finally with a HiVi RT2 planar) are just not that good, and I haven’t yet had time or cash to buy an interesting drive-unit (i.e. a large dual-concentric, Unity, or that cool BMS coaxial compression driver) to fabricate something that is more reflective of my tastes. And I didn’t want to risk my sub drivers or cabinets on the bare-metal trunklid of the rental Buick Century I’m stuck with for a while because some moron in a “sport” “utility” vehicle smashed into my daily driver, a 1999 Volvo S80 T6 with the 5.1-channel factory stereo engineered by Dynaudio and twin turbos on the 2.8L straight six.
There was some neat electronics there, too. Most impressive was Rob Cheng’s LEAP/LMS measurement suite. Also, there was a 1957-vintage Marantz 8B amp for the more efficient speakers, courtesy of Audio Atlanta. He did most of his measuring while the rest of us were at lunch. I joined a group that hit a BBQ joint that I ate at for the first time. A very different atmosphere than the Highlands or downtown Decatur, but the food was lovely. So was our waitress, although I could not quite place her accent, which was vaguely Eastern European…
Critques? Well, not being one who can summon himself to be, well, anywhere early Saturday morning, I arrived late, and missed out quite a bit for that. Two speakers I was looking forward to hearing were Ken Perkins’ 8” 2-ways with the Acoustic Reality series xover circuit and Patrick Sun’s Peerless 6.5" HDS-based speakers. Didn’t get seat-time behind either of them. Also, I had to leave before I could get a good listen to Rob Cheng’s three-ways (Vifa XT –> 4”Audax HD-A -> Vifa M21). There were several others that I wanted to hear after seeing them, but that never happened. Shien Chang had some very complex, Avalonesque cabinets holding a three-way with a 130mm Peerless HDS midrange and a 12” woofer I didn’t recognise that I would have liked to hear.
In general, it was quite a successful and well-attended event. It’s always nice to put faces to names that come up on the LCD. Hats of to Rob, Gordon, and everyone who brought their creations for the rest of us to enjoy! It was a wonderful exposition of well-engineered speakers. There was a nice diversity of designs, with point sources and line arrays, sealed/vented/TL enclosures, big bucks designs and great affordable ones, and a wide range of efficiencies. OK, there weren’t any DIY dual-concentrics or dipoles, so I guess I’ll have to combine the two in my project for next year! One would be very hard pressed to go into any high-end audio dealer and find so many solidly engineered, good sounding speakers, let alone so many different but equally valid paths to achieving good sound. I particularly enjoyed the exposure to discrete line arrays, TLs, and series crossovers. Overall, my favourites were as follows:
1) Tannoy D500. Sorry that it's not a DIY one, but this speaker just does not seem to have a flaw.
2) Bob Brines' Peerless TL. Yeah, it's real light on cone area, so it might not hold up to Mahler or Shostakovich, but on what we listened to it was astounding.
3) Brian Bell's Thor.
3.1) Linus. I would have put the Linus at #2 except for two things. First, the loss of treble when standing up. Second, the sheer fact that it's hard to concentrate on the music when you have such HUGE speakers staring at you.
I also have a few ideas for my entry next year. It will definitely use a dual-concentric for the top end and perhaps be a dipole in the mids and bass. Perhaps a "triple 8" with a Radian 8" dual-concentric and two of the Audax aerogel woofers that Robert Cozine used. Or maybe a "triple 10" with an Adire HE10.1 and two to-be-determined 10" woofers. (Lambda?) Or an HE10.1 with dipole bass...
At any rate, it looks like the diminished value check from the idiot who hit my car's insurance company has already found a home...
Peace,
Jay

 

[Patrick Sun]

Jay, my Peerless HDS-based speakers are of the 6.5" variety (but you're right about the Ken Perkin's M21's being 8" drivers for his Odyssey speaker). Schien's speakers used the Morel MDT29 and the 5.25" Peerless HDS mid driver, I forget the model # of the Hivi woofer he used.