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items: how'd we get here (or where is this)?
items: Re: how'd we get here (or where is this)?

how'd we get here (or where is this)?
type: item
description: Advance apology for an apparent troll but it's just honest ignorance in its native habitat. Been all over the map trying to answer a sort of simple question caused by stumbling on this catalog page tonight. Basically, if we're 47 years past this, how come we need LF (and/or HF) reinforcement, too? Not talking about a specific design, more the whole type. Is it just different priorities or is it something else? Do people not make parts that'll do that anymore? Were those just marketing claims (and maybe optimistic)? Did they not care as much about pattern and traded a hole at xo? Do people hate big cabs so much that they trade LF and efficiency? Do "2-way people" all use them for HT so subs are already there? Do current preferences align more for clarity from swanky motors than FR? ... on and on--I got a million of 'em, but that's sort of my point. As near as I can tell, people have been making reflex + horn boxes for almost 80 years The priorites have moved a few times already. But, save for adopting some whole other thing, why do people seem to forego wider range responses? Even granting bunches of money--for example, those nice-motored midbass drivers are not so inexpensive--and we still need bass supplementation (?) Do the current standards for acceptable clarity at higher efficiency preclude reaching lower even in giant boxes even when granted non-trivial expense? I mean, why work soooo hard on driver spacing and phase and waveguides and all that--just to be band-limited and need one or both ends to be supplemented? Is it just because the drivers don't sort neatly into higher-volume "pro" or "auto" categories so there's just not work being done in those areas? At least these are what I'm wrestling with...not pointing at any one thing, just the "2-way way" in the higher-efficiency sandbox. Thanks for the bandwidth, the time, and the education.
creator: grindstone
date: 2011-12-31T08:55:32-00:00

Re: how'd we get here (or where is this)?
type: item
description: Altec made excellent speakers in that era. Not too bad by today's standards either. But they definitely don't compare with a properly designed modern matched-directivity two-way (waveguide) loudspeaker, even though they look similar. The following document tells you why, and even has a little bit of history too. You'll probably recognize an Altec horn in this whitepaper: High-Fidelity Uniform-Directivity Loudspeakers The differences are mainly the result of iterative improvements, not so much a paradigm shift. What Altec was trying to do in the 1950s is pretty much the same idea today. We're just better at it. Top-of-the-line modern drivers provide smoother response, lower distortion, higher SPL and dynamic range. Modern horn/waveguides have less internal reflections and are also able to generate a more constant pattern, one with fewer coverage holes. Crossovers are more thoroughly optimized too, made possible using today's acccurate measurement systems. As a result, response is better and the coverage pattern is more uniform. As for the matter of subs verses mains with deeper extension, to me, there is no question which is better. There are several qualitative reasons to split the deepest bass out to subs. Distortion (both harmonic and intermodulation) is reduced by splittiing the band and using dedicated subs. But the biggest improvement, in my opinion, is modal smoothing. See the following thread for more information about using distributed bass sound sources to smooth room modes: Room modes, multisubs and flanking subs
creator: Wayne Parham
date: 2011-12-31T16:19:30-00:00

Re: how'd we get here (or where is this)?
type: item
description: Thanks, Wayne. I had actually reread 2/3 of that before I posted and finished the rest of both again now. You have been singularly clear and generous in communicating your approach and rationale in a way that lifts all boats--sincere thanks. And again I wasn't pointing at any one design or even set of choices--just thinking the parts and possibilities for the Type would be farther along in all this time (and maybe they are and I'm clueless). There's a zeitgeist-thing these years, still. Maybe you don't feel as much because you've been so consistently on your own path for so long. Zilch et al, even Earl a good ways back, lots of mindshare. It's like when everyone was running UL amps because that was the thing
creator: grindstone
date: 2011-12-31T22:03:14-00:00

Re: how'd we get here (or where is this)?
type: item
description: Yeah, you're right. I found this path three decades ago and never looked back. There are other design types that have come and gone, the darlings of the day for audiophiles. But in this approach, I've never wavered. It's the best way to build loudspeakers for high-fidelity, in my opinion. I was lucky, I suppose, because I sort of stumbled across this design approach. I liked Klipsch speakers as a kid, but didn't like their warts. They were powerful, but could be harsh. When I decided to take that design concept but use better drivers, I found night-and-day better sound. I ditched the folded basshorn, opting for the simpler expansion formed by the walls extending away from the apex of the corner. The extra efficiency provided from an exponential throat expansion wasn't needed for home hifi, and removing the folds that formed this expansion prevented the problem of having vocals going them. Pushing that Klipshorn to 400Hz made vocals pretty wooly sounding. My corner speakers, with 22xx series JBL drivers and constant directivity horns, sounded so much better and had the advantage of sounding good everywhere in the room, not just directly on-axis. I realized that there were two features that contributed to the success of my early corner speakers, first being the quality drivers and second being the constant directivity created by the expansion of the corners. They formed a waveguide for the midbass and lower midrange, and when paired with constant directivity HF horns, one could achieve constant directivity through the whole audio band, from the Schroeder frequency upwards. These became the key features of all my designs. The evolution of these designs, for me, was iterative, mostly stepping back into radial horns to replace the spitty CD horns I originally used. I also optimized the crossover, and came upon a crossover design approach that I think is as close to ideal as can be found, while at the same time being sort of templated. It's not a generic crossover, becaus…
creator: Wayne Parham
date: 2012-01-01T00:28:09-00:00

Re: how'd we get here (or where is this)?
type: item
description: Hi Wayne, thanks for the great response. Very sweet sorta "I believe..." kind of smack-down post. FWIW, I didn't intentionally attack anything on-purpose but now I see how it could have come-off wrong. My deal was actually the converse; I was really sorta stumped at what seemed straight-forward & I knew that this was one of the _very_few_ places to float such an inquiry and have a chance at (a) tolerance and (b) a rational response. Thank You for taking the time to post and Thank You (and those who make it possible) for this place! Sincerely! I guess I'm making my way, fumbling along in plain-view, out-loud and w/o tact. As part of my (this weeks?) process, I think I finally "got" the beauty of the 8 pi. Still learning about and working the problem & I still always struggle with words for a lot of stuff in audio. I don't, for example, have much of any way to say how 10" drivers vs. say 15" drivers, on about any sort of material & crossed however-wise...in whatever kind of cabinet anyone likes, are pretty-much distinguishable from one-another. The words "tone" or "timbral <...this or that>" often come-up, but--I'll be honest--I've got nothing even though the differences have probably been well-established for ages. I just don't know what the words are to be able to talk about that, and yet I bet ya a pop that I can tell a 10 from a 15 (in about any kind of cab ya want) at 5 paces Sorta gets back to your post about, basically, liking what you hear. You (one would) use a large-format driver for <insert audio-words here> even though it doesn't do bass. In my non-audio lingo, "because pianos sound more right", etc. And hey--I'll personally trade quality of bass for quantity, for sure. Or quality of MR, more-properly, for extension. If I'm tracking, that's another way to say what you said. Probably none of this was worth a response, but I wanted to say thanks for taking the time and wanted to let you know that the characters didn't go to waste. I have begun to wonder, for…
creator: grindstone
date: 2012-01-05T08:44:44-00:00

Re: how'd we get here (or where is this)?
type: item
description: No offense taken. Comparisons with other loudspeakers are common, especially Altec and Klipsch. Each has a lot in common. My designs are more refined, but that's because they're more modern and I could take advantage or better drivers and better design tools. I truly stand on the shoulders of those earlier designs. The Klipsch cornerhorn was the inspiration for my constant directivity cornerhorn designs. Altec published a document that described how to aim the forward lobe by reversing phase and looking for the deepest notch. JBL went a step further in their whitepaper about the 4430. Each of these were pioneering efforts in their time, and I base my work on them, using those as a sort of starting point. So it's good to bring them up, and it makes a nice segue for discussion.
creator: Wayne Parham
date: 2012-01-05T15:14:39-00:00