roadworn Posted February 2, 2020 Share Posted February 2, 2020 Has anybody tried a set of the JBL L-300 lenses in front of their Forte or Herseys squawker?Seems that it might help in dispersing the mids so that speaker placemnet might be a bit more forgiving? Quote Link to comment Share on other sites More sharing options...
OO1 Posted February 3, 2020 Share Posted February 3, 2020 - Quote Link to comment Share on other sites More sharing options...
carlthess40 Posted February 3, 2020 Share Posted February 3, 2020 Is like to make these. Does someone have or know where a could get the build plans for then?Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
glens Posted February 3, 2020 Share Posted February 3, 2020 I love it!  The driver fastens to the back of the horn, and in front of the horn mounts the lens. Does everyone who calls the "horn" a "lens" see this? I sure hope so!  In answer to the question, it sure couldn't hurt to try it. Though those lenses were designed to disperse the pattern of a conical horn, and they may not be as effective for this application. Also, you wouldn't want to create a lopsided presentation off axis - that JBL tweeter was pretty good horizontally.  Personally, I'd be inclined to get the L300s up and running again unless some fool (in my opinion) has already parted them out and the lenses are all you've got... Except maybe for efficiency they'd likely kick butt against a Cornwall, especially a Forte or Heresy. Quote Link to comment Share on other sites More sharing options...
pzannucci Posted February 3, 2020 Share Posted February 3, 2020 3 hours ago, glens said: I love it!  The driver fastens to the back of the horn, and in front of the horn mounts the lens. Does everyone who calls the "horn" a "lens" see this? I sure hope so!  In answer to the question, it sure couldn't hurt to try it. Though those lenses were designed to disperse the pattern of a conical horn, and they may not be as effective for this application. Also, you wouldn't want to create a lopsided presentation off axis - that JBL tweeter was pretty good horizontally.  Personally, I'd be inclined to get the L300s up and running again unless some fool (in my opinion) has already parted them out and the lenses are all you've got... Except maybe for efficiency they'd likely kick butt against a Cornwall, especially a Forte or Heresy. Yes, increase the dispersion from a narrow conical horn, not on a horn with a wide open mouth (exponential, tractrix, etc) that is supposed to define the dispersion. 1 Quote Link to comment Share on other sites More sharing options...
Toz Posted February 3, 2020 Share Posted February 3, 2020 Technically speaking the HL91 horn is an exponential horn, it just maintains a round section and has a gentle rate of flair. It is not conical. The diffuser is there to shape the dispersion pattern. I would not use that on any other horn mouth. 1 Quote Link to comment Share on other sites More sharing options...
glens Posted February 3, 2020 Share Posted February 3, 2020 Correct. I realised afterward I'd meant to use the term "circular" but didn't bother to fix it since it'd been quoted already. Quote Link to comment Share on other sites More sharing options...
Blvdre Posted February 4, 2020 Share Posted February 4, 2020 A picture, for those who may be reading, but not familiar with that JBL design: Â Quote Link to comment Share on other sites More sharing options...
moray james Posted February 4, 2020 Share Posted February 4, 2020 I own a set of JBL L200B which use this dispersion lens. There is a reason why this design faded away. While the lens delivers on the intended dispersion it messes with the stage and image and the L200B sounds better with them off, I don't use mine at all. Get your L300 up and running with fresh caps they are a stunning loudspeaker which transcend time. 1 Quote Link to comment Share on other sites More sharing options...
glens Posted February 5, 2020 Share Posted February 5, 2020 That flyer image above fails to mention that the voice coils are (at least were) made with rectangular profile wire wound on edge. In my opinion JBL's drivers, at least of that era (lost touch sometime in the '80s) are the best available. I have a pair (in long-term storage since the foam surrounds disintegrated) of their smallest studio monitors from that timeframe. Beautiful cast aluminum baskets with a magnet structure using ALNiCo magnets. The magnetic field is focused entirely around the voice coil. You can take a handful of paper clips and throw them at the rear of the driver and every one of them falls away. Do the same at the front of the driver and they all stick in a circular pattern around the voice coil. I'm a huge fan of JBL of that era. They generally kicked butt on everyone, including Klipsch. Put those lenses back on the L300s, refresh the crossover caps, and enjoy! Who cares what the cabinets or grilles look like! Quote Link to comment Share on other sites More sharing options...
Marvel Posted February 5, 2020 Share Posted February 5, 2020 JBL manufacturing was impeccable! the woofers in my 4311s are works of art. If Eminence were to make all of their cast baskets with that touch of detail, we couldn't afford them. Quote Link to comment Share on other sites More sharing options...
roadworn Posted February 13, 2020 Author Share Posted February 13, 2020 On 2/2/2020 at 11:13 PM, carlthess40 said: Is like to make these. Does someone have or know where a could get the build plans for then? Sent from my iPhone using Tapatalk Look on Ebay, someone makes copies.. not plans. Probably a bit of CNC work involved Quote Link to comment Share on other sites More sharing options...
roadworn Posted February 13, 2020 Author Share Posted February 13, 2020 On 2/4/2020 at 4:13 PM, moray james said: I own a set of JBL L200B which use this dispersion lens. There is a reason why this design faded away. While the lens delivers on the intended dispersion it messes with the stage and image and the L200B sounds better with them off, I don't use mine at all. Get your L300 up and running with fresh caps they are a stunning loudspeaker which transcend time. Spoken like a true Klipsch guy! haha. I have been in many studios with the L100 and they are amazing speakers. I wish I could afford a pair. As I read the Klipsh fourms, the common complaint with many of the vintage cabinets seems to be the frustrating speaker placement needed to enjoy them. Just scratching my head. Quote Link to comment Share on other sites More sharing options...
glens Posted February 13, 2020 Share Posted February 13, 2020 Probably wasn't the L100 in the studios. It'd be 43xx (4311 in this case?). The "L" speakers were perhaps a bit prettier versions of their "real" brethren, which, at least up to some point in the hierarchy had better crossovers, and performed better, than the "L" versions. Quote Link to comment Share on other sites More sharing options...
pzannucci Posted February 13, 2020 Share Posted February 13, 2020 On 2/3/2020 at 2:37 PM, Toz said: Technically speaking the HL91 horn is an exponential horn, it just maintains a round section and has a gentle rate of flair. It is not conical. The diffuser is there to shape the dispersion pattern. I would not use that on any other horn mouth. Ah exponential chopped off to handle the lens. Thanks for the correction... now that I have seen a bigger picture.  5 hours ago, roadworn said: Spoken like a true Klipsch guy! haha. I have been in many studios with the L100 and they are amazing speakers. I wish I could afford a pair. As I read the Klipsh fourms, the common complaint with many of the vintage cabinets seems to be the frustrating speaker placement needed to enjoy them. Just scratching my head. I never thought the L100 was that great though that was 40 yrs ago. Did love the sculpted orange foam grills. Totally different animal than the L200/L300. Always lusted after those, if not for the sound but the "coolness" factor but compared to what is built today, I would like to see some folks totally freshen up / redesign the electronics in some of those old speakers to see if can push them well beyond based on new technology. Like the L100 classics though a lot of changes in the hardware. Quote Link to comment Share on other sites More sharing options...
Deang Posted February 13, 2020 Share Posted February 13, 2020 On 2/3/2020 at 2:48 AM, glens said:  The driver fastens to the back of the horn, and in front of the horn mounts the lens. Does everyone who calls the "horn" a "lens" see this? I sure hope so! I gave up pointing this out years ago. After a while, you just feel like you’re playing the roll of grammar police. Quote Link to comment Share on other sites More sharing options...
Marvel Posted February 13, 2020 Share Posted February 13, 2020 7 hours ago, glens said: Probably wasn't the L100 in the studios. It'd be 43xx (4311 in this case?). The "L" speakers were perhaps a bit prettier versions of their "real" brethren, which, at least up to some point in the hierarchy had better crossovers, and performed better, than the "L" versions.  My 4311s from the early '70s were walnut with black fabric grills. Actually prettier than the L100s, and cost less. I got a discount through a studio I visited, so the price was around $280 (listed for $329 at the time. Pro gear didn't follow the rules on the fair trade laws, so they could discount more where the retail stores could not) each, give or take a few dollars. It was a long time ago and I have lost the receipts. Crossovers on the 4311s are a weak point... a single cap on the mid and tweeter, along with an L-pad for each. Most studios bought them in gray, like the ones on the right in this pic.  Bruce Quote Link to comment Share on other sites More sharing options...
richieb Posted February 13, 2020 Share Posted February 13, 2020 } No doubt the biggest mistake of my audio life was selling custom built cabinets housing JBL LE15a, LE85 w/ potato masher horn and the two way JBL networks as shown above - young and dumb Quote Link to comment Share on other sites More sharing options...
roadworn Posted February 13, 2020 Author Share Posted February 13, 2020 11 hours ago, glens said: Probably wasn't the L100 in the studios. It'd be 43xx (4311 in this case?). The "L" speakers were perhaps a bit prettier versions of their "real" brethren, which, at least up to some point in the hierarchy had better crossovers, and performed better, than the "L" versions. Sorry, I miss typed, I ment, L300 is what I would like to have. Yes you are correct!  In the studios JBL had studio Biamp versions ofthe L300.... JBL 4333A Studio Monitor is the L300 studio version and it also had different woofer as well, I believe. The L100s were a completely different animal .No horn or cool dispersion device 🙂 Quote Link to comment Share on other sites More sharing options...
moray james Posted February 13, 2020 Share Posted February 13, 2020 don't discount the L200B which is a two way system and I believe with the acoustic lens removed sounds wonderful. Of course both the L200B and or the L300 could use new cabinets with flat baffles which place the mid horn at your seated ear level for best performance. Tilting baffles rarely work well. Quote Link to comment Share on other sites More sharing options...
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