rtaylor Posted March 17, 2005 Author Share Posted March 17, 2005 I think he likes it, gives him something new to discover.If you know cats they are always into something. Curious little bbbuggers Quote Link to comment Share on other sites More sharing options...
jwc Posted March 17, 2005 Share Posted March 17, 2005 On that last picture, why is there a square hole in the bottom of your new box. Shouldn't there just be a top hole for the bottom of the bass bin and two ports. by the way, are you gonna put port tubes in thoase? jc Quote Link to comment Share on other sites More sharing options...
J.4knee Posted March 17, 2005 Share Posted March 17, 2005 I too do not understand why you have not sealed the bottom of your ported box. More importantly what dimensions did you use for your ports and how long are the tubes you will be putting in there assuming you do. I know the box should be about 10 inches high but that is al I know about the dimensional measurements. What I really like is this is a completely reversible mod. My curiosity is peaked. So please do tell. Quote Link to comment Share on other sites More sharing options...
JohnA Posted March 17, 2005 Share Posted March 17, 2005 "I too do not understand why you have not sealed the bottom of your ported box." How are you going to screw it together? Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted March 17, 2005 Share Posted March 17, 2005 DUDE, did you know that's a Radio Shack woofer in there!?!!? It's not a K33 at all. just kidding. I think the double square cuts is so the mod can be permanently bolted on, and the old hatch replaces the cutout in the mod for access, yes? Do you have a source for the port tubes and what are the dimensions please? Michael- this is looking very promising.... Quote Link to comment Share on other sites More sharing options...
homemade Posted March 17, 2005 Share Posted March 17, 2005 I found the writing about the different f3's, etc. very interesting. I always loved the look of the LS's but remember them sounding very "thin" in the showroom. Now, getting the f3 down into the low 30's or even high 20's would be wonderful but there is one thing that I believe we're forgetting: this f3 and the proceeding octave will still be aprox. 10db lower in efficiency (due to the efficient horn loading of the bass from 70hz on up). If one compares the khorn to the LS freq. response they are very similiar except for the lower octave of bass. I really wonder if an LS can have decent bass by using a simple 10-15 band eq. and jack up the lower octaves sufficiently and be done with it. I know that people here on the forum object to using an eq. but even with the mods you'll still be down 10db at 30-45 hz and that will still sound "thin". Quote Link to comment Share on other sites More sharing options...
J.4knee Posted March 17, 2005 Share Posted March 17, 2005 ---------------- On 3/17/2005 10:51:41 PM John Albright wrote: "I too do not understand why you have not sealed the bottom of your ported box." How are you going to screw it together? ---------------- Yeah I understand that but why not then seal the bottom like is done on the unmodified LS. Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 The addition will be sealed both to the bottom of the bass bin and then the original bass bin cover will be installed to the bottom of the addition. Yes they get two 4 inch ports, I'll start them out at 10 inches long and work from there. I have the port tubes but ordered the wrong ones, I wanted the flared ones but got the straight ones, will be ordering the others soon. Until then I'll work with these. I believe the only difference would be in a decrease in port noise. Randy Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 ---------------- On 3/17/2005 9:37:59 PM jwcullison wrote: On that last picture, why is there a square hole in the bottom of your new box. Shouldn't there just be a top hole for the bottom of the bass bin and two ports. by the way, are you gonna put port tubes in thoase? jc ---------------- The pictures are of the lascala upside down, when the work is done I'll flip them over. Need hole against the bass bin for obvious reasons, need the other opening to screw the addition to the bass bin and to work on the tubes. Will be adjusting them to their final length. Randy Quote Link to comment Share on other sites More sharing options...
Klewless Posted March 19, 2005 Share Posted March 19, 2005 homemade stated "I really wonder if an LS can have decent bass by using a simple 10-15 band eq. and jack up the lower octaves sufficiently and be done with it. I know that people here on the forum object to using an eq. but even with the mods you'll still be down 10db at 30-45 hz and that will still sound "thin"." He makes a very good point. To eq that could require one very big amplifier! And if you like the music loud, potentially a closet full of replacement woofers. Quote Link to comment Share on other sites More sharing options...
DrWho Posted March 19, 2005 Share Posted March 19, 2005 ---------------- On 3/17/2005 11:09:22 PM homemade wrote: I found the writing about the different f3's, etc. very interesting. I always loved the look of the LS's but remember them sounding very "thin" in the showroom. Now, getting the f3 down into the low 30's or even high 20's would be wonderful but there is one thing that I believe we're forgetting: this f3 and the proceeding octave will still be aprox. 10db lower in efficiency (due to the efficient horn loading of the bass from 70hz on up). If one compares the khorn to the LS freq. response they are very similiar except for the lower octave of bass. I really wonder if an LS can have decent bass by using a simple 10-15 band eq. and jack up the lower octaves sufficiently and be done with it. I know that people here on the forum object to using an eq. but even with the mods you'll still be down 10db at 30-45 hz and that will still sound "thin". ---------------- Just curious, where do you get these numbers from? It's been a while since I've read the write up about the mod, but I was under the impression that it would maintain the same efficiency...thus a "flat" response down to 30Hz. Ports can either add 6dB of efficiency or lower the frequency response by about an octave. The K-33 can already go down to 30Hz no problem (doesn't it have an Fs around 20Hz?) so porting it to 30Hz would would increase it's efficiency. The reason you can't just EQ the lascala is because it has a very low power handling capacity of 100watts continuous (yes i know 400 watts peak, but that only gives you an extra 6dB assuming no power compression). I don't have my charts handy, but doesn't the response of a horn loaded driver drop at 24dB/octave below the tuning point of the horn? To extend the frequency response of the lascala only half an octave (which would only be down to 40Hz), you would have to reduce the maximum output from 121dB down to 109dB. This doesn't sound like that big of a deal, but the power compression and FMD will destroy the sound of the speaker. And all of this is assuming that the driver can even play that low without exceeding it's x-max (which I highly doubt). At the tuning frequency of a port, a driver (in an ideal world) doesn't even have to move at all. It seems like a waste to me to have a rear compression chamber that just sucks up the sound and creates heat instead of producing sound. The cool part about this mod is that it maintains the same acoustic spring that the original chamber was designed for. Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 question, what would be the best material to stuff these with. was just going to use some fiberglass insulation from a remodel but must have thrown it away so if i'm going to buy something may as well be optimum, Randy Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 Listening now, definately lower,,,, Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 Listening to Peter, So. I'll sisten for awhile before saying anynore. Quote Link to comment Share on other sites More sharing options...
Marvel Posted March 19, 2005 Share Posted March 19, 2005 You have those in a pretty small room, don't you? I wouldn't use fiberglass, as it can tend to break up and blow into the room. Some polyest fiberfill should work. You can order from Parts Express, or get some from a fabric store. Below is a pic of the cusom LS bass cab built by Frode. He has an Oris horn on top (I think it is an Oris). In the pick, the cabinet in on its side. Below that are the repsonse figures with the mod, using different port lengths. My buddy Thermio and I both scratch built a set of LS bass cabs and he did the djk mod to them. He took measurements on one cabinet as the mods progressed. Here is the data: 200 160 125 100 80 63 50 40 31 25 20 HZ 77 80 79 73 72 78 68 60 61 52 51 dB Stock, mouth braced 76 78 78 73 69 75 65 60 66 56 52 4.5 cuft, no ports 76 78 77 75 74 80 70 60 68 54 54 Two 4"dia 10" ports 76 79 78 76 75 80 71 60 68 54 53 Ports cut to 7" The interesting thing with 10" ports is the boxes went deep, but the snappy, fast horn sound was lost! Cutting the port length to 7" brought the snap and speed back to same as stock, plus the lows remained, esp. at the 31Hz box tuning point. This data is with K33E driver and light stuffing. We think a K43E in this box would be superb, but haven't tried it yet. I'm going to try the mods using two 4" ports with both ends flaired (Thermio used 4" PVC). Flaring is supposed to reduce distortion and possibly increase the gain. Parts Express sells the kits. Neither of us is going back to stock. Pete Quote Link to comment Share on other sites More sharing options...
NOSValves Posted March 19, 2005 Share Posted March 19, 2005 This looks like the Ports to get ? http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=268-352 Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 Yes, those are the ones I thought I was ordering but somehow got screwed up. I'm liking what I'm hearing. Altho I feel I need to dampen the inside of the cabinet with something else besides the foam. Looking for some ideas here. Help.With the speakers set up like they are now it seems that they are a little more forward. Not a lot but some. They do seem to dig down a little deeper and I do not notice a loss of slam. Marvel, they are in a somewhat small room. They are in a 12 foot part of a 30 foot room with alot of HOLES at the far end. The K-Horns never worked here. I'll post some pics. Randy Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 This is looking back into the room from the speakers viewpoint. Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 This is looking into the hallway and kitchen, no small opening here. I believe this makes the room look a little bigger to the speakers. Quote Link to comment Share on other sites More sharing options...
rtaylor Posted March 19, 2005 Author Share Posted March 19, 2005 This is looking into the kitchen with my lovely wife Lois doing something or another. lol. She puts up with alot of stuff! Quote Link to comment Share on other sites More sharing options...
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