longdrive03 Posted September 27, 2016 Author Share Posted September 27, 2016 I forgot to mention the front edge trim is 3/8" thick cherry. The color of the bottom piece is lighter because it was sawed but should darken over time and exposure to sunlight. Here's a pic of the EV SM120A horn and ND6X driver. 1 Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted September 27, 2016 Author Share Posted September 27, 2016 Front view of horn. 1 Quote Link to comment Share on other sites More sharing options...
karlson3 Posted September 27, 2016 Share Posted September 27, 2016 Cool - are you going to run a tweeter at SM120's throat plane? - or up front as in the Sentry ? Wow! - I just noticed your fancy wide band compression driver. Do some SM120/driver combos require a 2nd order highpass for ~ flat operation? - Some years ago I graphed a beat old 1828 on 511, SM120, and Cobraflex - the SM120 had a depressed area "devil horned" - maybe it was just the value of capacitance vs that driver's Z(? - I'll graph my SM120) What's a good filler for SM120 type horns? mine IIRC have a few chips missing Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted September 27, 2016 Author Share Posted September 27, 2016 Karlson, Right now I'm experimenting with this as a two way with ND6X driver handling 500hz up. Sounded good to my ears but I need to get a friend to run some tests. I plan on using a 12db high pass at 500hz now. The horn is rigid injected urethane as I recall so not sure what filler would be good. Bondo? Epoxy??? Dunno. If I do go three way on this I may use a separate tweeter in plane with the mid. Still not sure I'll use the 120a horns but I had them here so I'm using them now. I notice there is a hole on one side of the horn which I assume is there to allow the tweeter wire to connect if you mount a tweeter in the mouth frame. Any info you can share is appreciated. Thanks. Moray James usually chimes in on these discussions and he has experience with these horns as I recall. Quote Link to comment Share on other sites More sharing options...
karlson3 Posted September 27, 2016 Share Posted September 27, 2016 SM120 is kind of a small horn - not a lot of mouth area nor path - the one I have in my back room has no hole for wiring - guess the wiring to ST350B was from the front. At the bottom of my SM120 there's attached the Sentry IVB 3-way metal crossover box. This SM120 is in pretty good physical shape - wonder what kind of paint might make them more presentable ? Sentry's W basshorn is more sensitive than a K-horn when loaded with 2-pym1298 in parallel. Quote Link to comment Share on other sites More sharing options...
Marvel Posted September 28, 2016 Share Posted September 28, 2016 K3, I have a pair or EV1828 drivers I used for a while on my previous pair of LS. I will be using them on my LS I am refurbing. While I didn't take any measurements, the 1828 drivers sounded good on the K400 horns. Marvel Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted September 28, 2016 Author Share Posted September 28, 2016 K3 I don't know what paint might work. May use a rattle can after filling any dents/nicks with bondo or another material. Mine are in good shape but look "dull". I don't know if they are paintable but I'll check that out. So far I love the ND6X crossing over at 500hz. It is about 113db per EV specs and I need to tame it down to 104. I'm using an lpad now to match levels. As I understand the autoformer you double the multiplier of impedance for each 3db of increased attentuation. At -9db I should multiple the 8.6ohm driver impedance by 8 which gives 68.8ohm as the mid ohm figure and the crossover calulator shows i need a 4.6uf cap to feed the 3504 for a 6db slope at 500hz. Quote Link to comment Share on other sites More sharing options...
avguytx Posted October 6, 2016 Share Posted October 6, 2016 It's been quiet... How are they coming? Quote Link to comment Share on other sites More sharing options...
zobsky Posted October 6, 2016 Share Posted October 6, 2016 What are you using for a crossover and do you need to EQ the SM-120? Thanks Quote Link to comment Share on other sites More sharing options...
Tom Mobley Posted October 13, 2016 Share Posted October 13, 2016 did you see my old Belle build thread? the forum software has been through iterations since then, my links are no good. I used the heat lock stuff on a bunch of veneer. worked out good mostly. Quote Link to comment Share on other sites More sharing options...
avguytx Posted October 19, 2016 Share Posted October 19, 2016 Are ya done yet??? On building the bass bins, did you just glue and clamp the pieces together or use glue and screws (or nails, etc) to attach everything? I was just wondering if they were put together with glue/screws and then veneer over that. I need some bigger clamps to attempt the glue/clamp method. Quote Link to comment Share on other sites More sharing options...
zobsky Posted October 19, 2016 Share Posted October 19, 2016 2 hours ago, avguytx said: Are ya done yet??? On building the bass bins, did you just glue and clamp the pieces together or use glue and screws (or nails, etc) to attach everything? I was just wondering if they were put together with glue/screws and then veneer over that. I need some bigger clamps to attempt the glue/clamp method. Thats what harbor freight is for - cheap clamps My preferred method is glue, clamp, 18Ga brad nails Screws are overkill though I did use some pocket holes (just so I could disregard my own advice) Quote Link to comment Share on other sites More sharing options...
avguytx Posted October 19, 2016 Share Posted October 19, 2016 I thought about pocket hole screws using a Kreg jig and also brad nails for some areas. But since I'm working with Baltic Birch and not veneering anything, I was going to go the no nail or screw route in visible areas and maybe nails/screws in other obscure areas. Yep....time for a trip to Harbor Freight. They are about 40 minutes or so away...not too bad. Quote Link to comment Share on other sites More sharing options...
zobsky Posted October 19, 2016 Share Posted October 19, 2016 1 hour ago, avguytx said: I thought about pocket hole screws using a Kreg jig and also brad nails for some areas. But since I'm working with Baltic Birch and not veneering anything, I was going to go the no nail or screw route in visible areas and maybe nails/screws in other obscure areas. Yep....time for a trip to Harbor Freight. They are about 40 minutes or so away...not too bad. Depending on the grade of baltic birch you use, it may or may not look good with a plain oil or poly finish. I found that out the hard way after building mine. Regardless, birch doesn't take stain well or you may want to play with some scrap first before committing to the build. Lastly, if you are set on not veneering, make sure you set up your cut list so the top and bottom faces of the mid-high cabinet sandwich the sides, ... unlike the top and bottom of the bass cabs. The plys of the birch will look nicer (from a visual perspective). See pic for clarification. Also, pay attention to which direction the grain flows when marking out your cuts since you wont be covering up anything with veneer later on. Don't ask how / when I realized this 2 Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted October 27, 2016 Author Share Posted October 27, 2016 Been missing in action for a while due to work.. I used glue, clamps and 2.5" screws recessed to attach the 1.25" sides to the bottom and top of bass bin, and the back of the sides to the back - then filled, sanded and veneered using iron and Heatlock. I used 1 5/8" screws to attach the bottom and top to the sides. Veneer the back, then sides then top to overlap. Have the parts cut out for second bass bin and will work on this weekend. Have a possible buyer for the cabinets so I'm glad I haven't built the top mid/hf cabinet which I plan to mount on spacers on the bass bin. Still not sure what horn to use if potential buyer doesn't buy. Might try the 11 x 17" ebay horn which appears to be a good choice. I'll need adapter from 1.4" ND6X to 2" throat. I wet sanded the poly after several days of drying then used Minwax wax and 0000 steel wool and then buffed. It is very smooth. Quote Link to comment Share on other sites More sharing options...
avguytx Posted October 27, 2016 Share Posted October 27, 2016 Awww, man. Already have them sold huh? Well get a little listen time in first. Quote Link to comment Share on other sites More sharing options...
avguytx Posted October 31, 2016 Share Posted October 31, 2016 Another question... How is the back panel (with the ramps) attached to the 4 sides ? Clamp and glue only? Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted October 31, 2016 Author Share Posted October 31, 2016 AV - these aren't sold yet but I have an interested possible buyer that wants to come see them in person. I may do it differently than others but I attach the veneered doghouse/motor board to the back panel with ramps with liquid nails of the equivalent, clamp nail/screw, then attach that to the bottom using glue/clamp/screws, then glue, clamp,/screw the top to the doghouse and back, then attach the sides (veneered inside) to the bottom top and back using glue/clamps and 2.5" square drive screws ( due to the 1.25" thick sides). Recess and fill all screw holes. Then I sand smooth and veneered the back then sides then top. I'm using solid cherry wood on the 2" risers. I've attached pics. The second one is nearly built except for attaching one side, sanding, veneering, applying front edge trim, finishing and then rubbing finish. Hard stuff is done. 1 Quote Link to comment Share on other sites More sharing options...
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