formica Posted August 20, 2006 Share Posted August 20, 2006 I'm designing my centre channel, and I have a simple question to get this thing moving... has anyone measured / calculated how much volume (space) the K401 displaces? My Centre Cornscala will have the all the components share the same box, so I'd like to adjust for the larger K401 vs the K600... and, yeah.... I'm still feeling lazy.... hoping someone can save me the time of measuring one up. [] Thanks... ROb Quote Link to comment Share on other sites More sharing options...
Daddy Dee Posted August 20, 2006 Share Posted August 20, 2006 It does seem like I've seen a person or two on the forum quote the volume of these horns. One way, easier than doing the math would be to fill the horn with water, and pour it into a measured container. Of course, that wouldn't be precise, but pretty close in a quick and dirty kind of way. Quote Link to comment Share on other sites More sharing options...
Deang Posted August 20, 2006 Share Posted August 20, 2006 so I'd like to adjust for the larger K401 vs the K600 Looks the difference between 600 and 401 is 199. Quote Link to comment Share on other sites More sharing options...
formica Posted August 20, 2006 Author Share Posted August 20, 2006 so I'd like to adjust for the larger K401 vs the K600 Looks the difference between 600 and 401 is 199. lol... sweet... [] actually i've found quite a few posts about the K600 (about 113in3) but none for the K400.... and wasn't in the mood of submerging a K400/K55 if the numbers were available.... [] I also seem to remeber seeing those... but can't seem to pop them up with the search... ROb Quote Link to comment Share on other sites More sharing options...
Guest " " Posted August 20, 2006 Share Posted August 20, 2006 Well it is not 418 inches. 418 inches is the internal volume of the k-401. Garden hose+fill k401 with water+dump water into container+determine the volume of the water in the container method. Don't have a container big enough for displacing the k-401 Quote Link to comment Share on other sites More sharing options...
formica Posted August 20, 2006 Author Share Posted August 20, 2006 Well it is not 418 inches.... 418 inches is the internal volume of the k-401.Thanks... at least we are getting close. [] I'd be surprised if the actual horn displaces more than 5% of that.... so ± 440in3 total? Anyone know how much the K401 weighs? (i could backward calculate the plastic's volume based on an average unit weight of plastic) ROb Quote Link to comment Share on other sites More sharing options...
DrWho Posted August 20, 2006 Share Posted August 20, 2006 lol Rob, you're talking a difference on the order of 0.1 cubic feet between the 600 and 401. I think you might be better off just ignoring the difference [] It comes to about a 0.1 dB net difference over a small range of the response... Quote Link to comment Share on other sites More sharing options...
formica Posted August 20, 2006 Author Share Posted August 20, 2006 lol Rob, you're talking a difference on the order of 0.1 cubic feet between the 600 and 401.ummm... actually it's in the order of 0.2ft3 []... but yeah, pretty insignificant (esp compared to the T/S variances in the K33). Quote Link to comment Share on other sites More sharing options...
DrWho Posted August 20, 2006 Share Posted August 20, 2006 Fine, a max 0.3dB difference [] (regardless of T/S parameters) Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 20, 2006 Share Posted August 20, 2006 don't you want the cabinet displacement? that would be the exterior volume of the horn. Fill an adequately sized container with water. Mark water level then take a K400 with both ends sealed off and fully immerse it in the water. Mark new water level. Remvoe K400 and add measured amounts of water until the high water mark is reached. That is the displacement. M Quote Link to comment Share on other sites More sharing options...
jwc Posted August 20, 2006 Share Posted August 20, 2006 I'll make this easy for you water tested external K401 with K55 driver about 277.66 cubic inches external K601 with K57 driver is 112.89 cubic inches problem solved jc Quote Link to comment Share on other sites More sharing options...
Daddy Dee Posted August 20, 2006 Share Posted August 20, 2006 Way to go JC Quote Link to comment Share on other sites More sharing options...
formica Posted August 20, 2006 Author Share Posted August 20, 2006 I'll make this easy for you water tested external K401 with K55 driver about 277.66 cubic inches external K601 with K57 driver is 112.89 cubic inches Thanks... water tested, huh.... remind me not to lend you any drivers you'd like to know the volume for... [] Design is pretty much done... and the only catch right now is my box is too big once i squeeze the K401 inside... but to small if split HF and LF bins. It would give me the opportunity to correct the Cornwall's bass hump, but that would also change the character and efficiency of the bass section (requiring a crossover mod). I haven't played with all the numbers yet, but I may keep it original and just use a wooden filler to reduce the volume by about 3ft3. BTW, what a large variance in K-33's T/S parameters posted in the past! ROb Quote Link to comment Share on other sites More sharing options...
BEC Posted August 20, 2006 Share Posted August 20, 2006 Rob, Are you using the new K-33Es or the ones with the square magnets made before 1985? I have some data I measured on both types a few years ago. Bob Crites Quote Link to comment Share on other sites More sharing options...
formica Posted August 21, 2006 Author Share Posted August 21, 2006 I haven't decided but I am also considering your CW1526 (sp?). I figured I can get the wood cut before getting the drivers as I prefer doing it outdoors to avoid to much dust inside my home. I wouldn't mind seeing your T/S measurements for the three... to compare to what I've collected. I have to agree that the round magnet K33 model's the weirdest so far... ROb PS: this is a preliminary sketch CornScala Model (1).pdf Quote Link to comment Share on other sites More sharing options...
boom3 Posted August 21, 2006 Share Posted August 21, 2006 As a side note...I used the a K401 in my center channel. The throat has to be supported, of course. I made a post out of 2 x 2 poplar stock and notched one end to receive the "fin" at the throat (there are two, so the horn may be mounted either side up). I then drilled a hole through the post, and passed a brass bolt through the post and the hole in the fin, securing it with a brass nut & washer. In this manner, the throat rests on the post, and the stress is taken off the fin, as would be true if a simple angle bracket was used. Quote Link to comment Share on other sites More sharing options...
BEC Posted August 21, 2006 Share Posted August 21, 2006 Rob, Here is my effort at measuring the T/S parameters of a new round magnet K-33E and two 30 year old square magnet K-33Es. Bob Crites TStest1-1.pdf Quote Link to comment Share on other sites More sharing options...
jwc Posted August 21, 2006 Share Posted August 21, 2006 To include the K401 in the cabinet makes it very deep. I did it by making it look like a la scala. I have one of bob's woofers and made a stab to tune it myself. This does tske that hump out but it doen't have the slam. The woofer goes much lower. Have a 6.5 Cu ft with two 4 inch ports. Tall cabinet. Quote Link to comment Share on other sites More sharing options...
formica Posted August 21, 2006 Author Share Posted August 21, 2006 To include the K401 in the cabinet makes it very deep. I did it by making it look like a la scala. The depth is controlled by the K401, the height is controlled by squeezing all the drivers on the motorboard, technically leaving me only the width as a variable (still have to fit the K401's mouth in there too). Thing is I'm also very picky on appearances... and really want to have an even gap around this centre channel and my inwall recess.... so that's why I'm left with adjusting the volume with a filler in the box. I have one of bob's woofers and made a stab to tune it myself. This does tske that hump out but it doen't have the slam. The woofer goes much lower. Have a 6.5 Cu ft with two 4 inch ports. Did you try the CW1526 in the same enclosure alignment as the Cornwall... or re-tuned according to the T/S parameters? I haven't compared the CW15 to these new T/S numbers... but it does seem to model similarly to the old square magnet K33 numbers supplied by eminence. It's one of the reasons I was tempted to leave the design (I used the late 70's volume and tuning) as is... and drop either a square magnet K33 or a CW15 into the enclosure. Bob, could you post the full T/S on the CW1526? I was missing Cms, Mms, etc... and i'm not keen on backward calculting those. BTW, I will probably hold up the back of the K401 using a brace running left to right and an L bolted to the horn and the brace. ROb Quote Link to comment Share on other sites More sharing options...
jwc Posted August 21, 2006 Share Posted August 21, 2006 No I didn't try the new woofer in a standard Cornwall cabinet. I don't have one to tool with anymore. Bob sent me the T/S info and he later told me that what he sent me was from Eminence and it was incorrect. It doesn't matter in my case as it "tunes" close to the K33. What I did was convert the Cornwall tuned cabinet to just a larger size enclosure and changed the port from rectangle to dual round ports. Did this in WinISD. Now I RTA'ed the woofer in the 6.5 cu ft box with two 4" inch ports at three different lengths. Interesting....I settled on 7". This is coincidental as those people porting there La Scalas find the exact same port sizes to sound best with that mod. Now I know that application is different. Anyway...tried 10" and 5". The 5" "sounded" more like a Cornwall. However, wasn't trying to replicate the Cornwall here so went with the 7" that flattened that bump you are referring to and made a little more low end. One other thing about the K401. I don't think it is tried and true inside the cabinet. I'm sure it will work....but you will have to mount it inside the motorboard which just adds more depth. Also....Make sure to keep the width at 24 1/2 as the K401 requires those "flares" to extend the horn. If you want to make the port just like the Cornwall, then you are committed to a total width of 25 1/4. Bob squeezed his test box in some. to make a cube.....24 x 24 x 24. My Cornscala is 25 1/5 wide like a Cornwall and the same depth and height as a la scala. jc Quote Link to comment Share on other sites More sharing options...
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