Emile Posted May 22, 2018 Share Posted May 22, 2018 Hope you experts can give me some guidance as I am completely lost Trying to build a new cabinet for a 12" woofer (and a 14x8" horn). All info I have seen is very conflicting; showing volume sizes differing by up to 300% Background ... did not like my (small) Klisch KV2 center speaker (with KPT-904 mains), so was looking for another solution. Found a Yamaha stage monitor speaker (S112IV; 12" woofer and 14x8 horn w/ 2" diaphragm, pic at end of post), and was very pleased with the sound. FYI, forum veteran @Thaddeus Smith tried it with a similar (15") Yammie and I'm pretty sure he is impressed also. But; it is a stage monitor, meaning "rat fur" cloth covering which yields a 0/10 on the WAF meter. So; why not put the components in another (wife friendly) walnut box - haha with a Klipsch logo? (And, to keep the size small, I thought a sealed box would be OK as it is a center speaker and doesn't need low bass.) After days and days, I finally got the T/S specs from Eminence (mfg of the woofer; Yamaha model JAY51200). They are: 05-RE OHMS 5.66 13-FS HZ 47.72 06-LE MH .93 14-MMS GMS 34.80 07-QM 3.10 15-CMS mm/N .3195 08-QE .480 16-RMS NS/M 3.3707 09-QT .420 17-VAS LTRS 127.19 10-XMAX MM 3.00 18-SD SCM 532.36 11-BL TM 11.05 19-EBP 98.6 12-EFF % 2.75 20-SPL dB 96.4 So; plugged these into a couple of online cabinet size calculators and got 3-4 cuft as recommended for a SEALED box (over 7 cuft for ported). First comment; does not make much sense as the original Yammie box is ported and ONLY has an internal volume of about 2.0 cuft. (I "***-umed" that I could build a sealed box even smaller than that.) Anyone ???? Next it gets even more confusing. Eminence told me a "cheaper' replacement for this driver is their model "Beta-12A-2." Eminence shows a ported box volume for this at 4.75 cuft and a sealed box (with heavy polyfill) at 0.9 cuft. ????? 1/5th the size ???? Parts-Express recommends 2.36 cuft sealed and 7.35 cuft ported. PE's 2.36 vs Eminence 0.9 cuft just because of some polyfill ?????? Obviously these numbers are "all over the place" and I have NO CLUE why Furthermore, don't want to spend $200 (baltic birch and veneer) plus weeks building a box which is completely wrong My only "uneducated" solution is to "copy" the Yamaha design ... or throw it away as my wife will not allow a "rat fur" box Many, many thanks for any inputs/thoughts Cheers, Emile Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted May 22, 2018 Share Posted May 22, 2018 Start a thread and see if someone has a Parts express woofer tester and see if they'd check your driver and give you the T/S parameters for that particular driver. As much of this stuff that I play with, I should have one but don't Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted May 22, 2018 Share Posted May 22, 2018 https://www.parts-express.com/dayton-audio-dats-v2-computer-based-audio-component-test-system--390-806 1 Quote Link to comment Share on other sites More sharing options...
twk123 Posted May 22, 2018 Share Posted May 22, 2018 The only think I can suggest is throwing it in one of these. Get a cutting drill bit and drill a port about the same size as the original cab. https://www.parts-express.com/pa-knock-down-trapezoid-plywood-speaker-cabinet-for-12-driver--245-324 1 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 14 minutes ago, twk123 said: The only think I can suggest is throwing it in one of these Thanks @twk123. Haha ... Great minds think alike ... that was my first thought also Read the reviews on this and the quality is not "great." Plus thought I could make the box even smaller by going to a rectangular design vs the trapezoidal shape Cheers, Emile Quote Link to comment Share on other sites More sharing options...
Thaddeus Smith Posted May 22, 2018 Share Posted May 22, 2018 Since you're already in the frame of mind to build and veneer, it may be easier to just rip off the carpet, scrape whatever glue remains, and apply veneer. I think mine are of a slightly older generation than yours, but I pulled the drivers on one and it looks like they use a really dense particle board for primary construction, with some blocks of actual plywood in place for the hanging eyelets to bolt through. Standard fiberglass batting and a thick piece of carboard stapled into place to cover over the area where the transport handle lives. I think I've resigned to the fact that mines going to stay carpeted and I'll just throw a fresh coat of satin or flat black on the grille and corner protectors. The yamaha badge appears to be stuck on using double sided adhesive. It's solidly built, but very obviously never intended to see the inside of a living room. 1 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 14 minutes ago, Thaddeus Smith said: Since you're already in the frame of mind to build and veneer, it may be easier to just rip off the carpet, scrape whatever glue remains, and apply veneer. [edit] It's solidly built, but very obviously never intended to see the inside of a living room. Thank you SIR Yes; thought about that but all edges are "rounded" and as an amateur woodworker, I have no clue how to veneer those Yes, my wife strongly agrees ... "never intended to see the inside of a living room" Cheers, Emile Quote Link to comment Share on other sites More sharing options...
Thaddeus Smith Posted May 22, 2018 Share Posted May 22, 2018 You could always whip out the "Well Michael got one too and his wife doesn't seem to mind" and see how that works for you. 2 Quote Link to comment Share on other sites More sharing options...
twk123 Posted May 22, 2018 Share Posted May 22, 2018 Here is an idea: since it is front ported anyway, why dont you just build a box for the whole Yamaha speaker to fit into with dark grill cloth and nobody would know the difference. On a side note, are those separate cabs for the KPT 904 horns? That looks really clean. Lol I thought they were cornwalls at first. 1 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 1 minute ago, Thaddeus Smith said: "Well Michael got one too and his wife doesn't seem to mind" Going to try that Funny part is ... got this speaker last Thursday and put it in front of the fireplace ... wife did not "notice it" till 1/2 hour ago ... her comments were "not positive" ... Haha 1 Quote Link to comment Share on other sites More sharing options...
Thaddeus Smith Posted May 22, 2018 Share Posted May 22, 2018 3 minutes ago, twk123 said: Here is an idea: since it is front ported anyway, why dont you just build a box for the whole Yamaha speaker to fit into with dark grill cloth and nobody would know the difference. And then there's that. I really like this solution.. 1 2 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 3 minutes ago, twk123 said: Here is an idea: since it is front ported anyway, why dont you just build a box for the whole Yamaha speaker to fit into with dark grill cloth and nobody would know the difference. On a side note, are those separate cabs for the KPT 904 horns? That looks really clean. Lol I thought they were cornwalls at first. Yeah ... that is the plan. Just trying to do it right re cab size, but terribly confused. For the woofer only recommended sizes range from 0.9 to 4 cuft ???? Also ... have some heritage cloth left over from my (little) project of grilles for the KPT bass boxes and separate cabinets for the horns. YES; WAF! Cheers, Emile Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 5 minutes ago, Thaddeus Smith said: And then there's that. I really like this solution YES ... 2 cuft as in the original box or 7 cuft as "recommended." The numbers don't make any sense to me Quote Link to comment Share on other sites More sharing options...
Thaddeus Smith Posted May 22, 2018 Share Posted May 22, 2018 3 minutes ago, Emile said: Yeah ... that is the plan. Just trying to do it right re cab size, but terribly confused. No no, build a box that will fit the entire speaker cabinet that you currently have inside of it. Volume never changes and you get a shape that's only slightly bigger in most dimensions and then you have easy angles and material to veneer. Then grill cloth the whole front. 3 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 5 minutes ago, Thaddeus Smith said: No no, build a box that will fit the entire speaker cabinet Michael, interesting thought and certainly less work Let me "sleep" on that one Bad part is that it will then weigh 60 lbs instead of 40 lbs 1 Quote Link to comment Share on other sites More sharing options...
twk123 Posted May 22, 2018 Share Posted May 22, 2018 25 minutes ago, Emile said: Michael, interesting thought and certainly less work Let me "sleep" on that one Bad part is that it will then weigh 60 lbs instead of 40 lbs At least you wont really have to move it very often. lol I am currently using a 50lb HIP that I put an internal amp into as a boombox and lug it all around the house. 1 1 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 22, 2018 Author Share Posted May 22, 2018 1 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 23, 2018 Author Share Posted May 23, 2018 Speaker cabinet volume calculations are a complete waste of time! OK; trying to see if I would get some comments on this Got the T/S parameters for my driver - see original post in this thread. Used several online calculators and the results averaged to about 2.5 cuft. Manufacturer (Eminence) recommends 0.9-1.3 cuft. Haha And even funnier ... have this speaker in the original PORTED stage monitor box with internal volume of about 2.0 cuft. Note; since it is PORTED it should translate roughly to a "closed" 1.0 cuft box. Guess I'll just buy some wood, and start cutting without measuring anything Cheers, Emile Quote Link to comment Share on other sites More sharing options...
karlson3 Posted May 24, 2018 Share Posted May 24, 2018 here's what I get in hornresp for a 3.35 cubic foot reflex tuned to around 37Hz I forgot to hit the lossy inductance model - but that would still be ok - am not sure how that works with this type driver. The cabinet could be made a bit smaller - maybe down to 75 liter if the lowpass inductor (if used) DCR is low. If somehow the bass sounds taut and musical, then might not be worth the trouble/hassle of a new cabinet 1 Quote Link to comment Share on other sites More sharing options...
Emile Posted May 24, 2018 Author Share Posted May 24, 2018 7 hours ago, karlson3 said: here's what I get in hornresp @karlson3 ; many many thanks! Quote Link to comment Share on other sites More sharing options...
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