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description: Audio advice and discussions with audiophiles and professionals. Free discussion forums, open to all and frequented by industry experts. Ask questions and get advice on stereos, speakers, hi-end amplifiers, pre-amps, home theater, tube hi-fi, turntables, vinyl, tweaks, music, films, video, DVDs and more.
items: 3 Pi plans request
items: Re: 3 Pi plans request
items: three π / four π comparison
items: Re: three π / four π comparison
items: Electronic crossover

3 Pi plans request
type: item
description: Wayne, Please send me the plans for the Lambda td12 and B & C DE-250 please. I have a curiousity and may try out the Lambda drivers as a few friends of mine tried out the 15" versions (td15x I think - rubber surround), and I thought they sounded decent. Have you thought of 4 Pi plans for Lamda 15" drivers yet? Regards, Ron
creator: spkrman57
date: 2010-06-21T14:28:52-00:00

Re: 3 Pi plans request
type: item
description: You've got mail! I'm not going to investigate the TD15 because I already have an upgrade path for the four π and seven π loudspeakers using the JBL 2226 woofer. The three π and four π speakers are almost identical in size and response, with the biggest difference being the four π is 3dB louder given the same input. I am extremely happy with the performance of both models, especially when fully upgraded with all the best driver options. The way I see it, the choice for the prospective owner becomes whether they want the best "corporate" speaker or the best "craftsman" speaker. JBL has all the resources for R&D and brings all that to bear when developing drivers. AE has very dedicated craftsmen who have done a great job too, making hand crafted drivers that also have all the right technologies. In my mind, there is no winner, both are excellent. It's like making a choice between the best that Porsche can do or the best that Ferrari can do. Both are excellent.
creator: Wayne Parham
date: 2010-06-21T15:06:41-00:00

Re: 3 Pi plans request
type: item
description: Hmmmm..... Quote: the choice for the prospective owner becomes whether they want the best "corporate" speaker or the best "craftsman" speaker. Not sure I follow either that or the Porsche/Ferrari analogy and kinda surprised you didn't show differing specs or test results, as you usually do. How do the drivers sound different, apart from efficiency?
creator: Bill Epstein
date: 2010-06-24T10:04:23-00:00

three π / four π comparison
type: item
description: I think you've probably seen the datasheet for the four π loudspeaker: four π loudspeaker performance data I haven't had a chance to do a spec sheet like that for the three π, but I do have a lot of data gathered during the design phase. I will make time this summer to drag one outdoor to measure. I'm a little slower doing that these days with the little 3-year-old Eddie running around. I did, however, make a video of the process I use to measure the position of the forward lobe (and vertical nulls), and it was done using a three π speaker. I thought it would be interesting to DIYers building similar matched-directivity loudspeakers, so I posted it online: three π response chart indoors This shows the three π loudspeaker being measured, and the response chart is clearly visible on the computer screen in the foreground of the video. This was done indoors, so room modes are clearly evident below 200Hz, but you can still easily see the overall response curve. It would just be smoother down low in an anechoic environment, a smooth gradual rolloff like T/S sims show. I wasn't really worried about room modes in this test, because it was a study of behavior in the crossover region. Again, I'll take these speakers outdoors sometime over the next couple of months and get a spec sheet like I have for the four π. Please forgive the car analogies, my mother's side of the family owned several Chrysler dealerships and has for three generations. Had Packards and Studebakers when those companies were still around too. My Dad opened the first large Porsche dealership in Tulsa in the early seventies, so I grew up around them, drove in the very first 930 Turbo that was delivered in 1976. I was always at the race track with Peter Gregg in the late 1970's, as his Brumos legacy made history on the track. He and my father were friends. So cars are in my blood. The reason I drew the analogy to the Porsche and Ferrari is, like both of those car companies, JBL and AE are both known for makin…
creator: Wayne Parham
date: 2010-06-24T15:05:09-00:00

Re: three π / four π comparison
type: item
description: I think you did a very good job of comparing things Wayne! I would have to say after much reading and hearing JBL 2226's and hearing a TD15X at Detroit AKfest (Cosmos speakers) that with the decline of availability of JBL drivers (no longer manufactured in the US as of Apr 2010), the Lambda's will probably be the easiest to obtain in the near future. I thought the TD15X sounded a lot like a 2226. It takes a larger cabinet, but the sound was very similiar to my ears. The TD15M is more efficient, but is closer to a Altec 416 driver and I'm not a fan of floppy surrounds on my drivers. Ron
creator: spkrman57
date: 2010-06-24T16:55:45-00:00

Re: 3 Pi plans request
type: item
description: You going to use an active crossover???
creator: SteveBrown
date: 2010-06-25T01:46:37-00:00

Re: 3 Pi plans request
type: item
description: You're asking Ron, right? All my speakers have passive crossover boards.
creator: Wayne Parham
date: 2010-06-25T12:36:04-00:00

Electronic crossover
type: item
description: SteveBrown wrote on Thu, 24 June 2010 20:46 You going to use an active crossover??? Steve, I plan on using the electronic crossover for a horn loaded 2-way in the future. I still have issues like getting a affordable preamp and finding a room to put them in. Right now I have 2 systems in the living room that I'm working on at the moment. So the bi-amped system will most likely be upstairs with the corner horns (Jensen backloaded design). Regards, Ron PS: Tubino in Toldeo wants to borrow my crossover in the meantime for his 2-way system using TAD drivers.
creator: spkrman57
date: 2010-06-25T15:26:44-00:00