Been a minute since I posted here. I have enjoyed my previous project for years. That project was some modified Polk T50s using a Dayton DAS 175-8 and morel MDT29. I fell in Love with the things I heard from that Morel tweeter, but in some respects the DAS175 has left me wanting for a more full sound. Or maybe it was just the overall path I took. I really should have gone 3 way instead of 2. So now I am going for Really 3 way. You see I came across some enclosures I had to have. Like Vintage solid wood. I think it is Walnut. I am including pictures and would like to hear what path you would take for a 3 way. But 1 st let me tell you the path I am heading into. I am leaning towards a Woofer & MidRange in the vintage enclosure and topping that with an articulating Tweeter enclosure on the top. And I will be at some point upgrading to a better subwoofer system. I want to make the sub system to stand these vintage boxes on for a some tall towers> These vintage boxes are currently 16.875 W x 23.750H x 18D internally. I have looked for weeks now trying to choose a proper midrange to work with the Morel MDT29 and the SB34NRX75-6. I also looked at the 10" SB woofer but this particular 12 can work well in a sealed box. Since I will use a subwoofer system I like the idea of faster transient response from a sealed woofer & sealed midrange. I would make the Tweeter box adjustable for depth and cant and also include the Xovr within that enclosure to the back. So an easy to get to crossover I could play with. Your thoughts and ideas? Would you be more apt to build something like the Gema? ???
SB34NRX75-6 + Undecided MidRange + Morel MDT29 ( or one with slightly higher SPL)
SB34NRX75-6 + Undecided MidRange + Morel MDT29 ( or one with slightly higher SPL)
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![20241117_173348[1].jpg](/community/data/attachments/1292/1292579-bcd66861214e69944f8317f6eba8c745.jpg?hash=LIAhW0d4Yt)
![20241118_110204[1].jpg](/community/data/attachments/1292/1292580-581e1c2c6078c3a4ec878700dd9c5908.jpg?hash=82Bl1mznOu)
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The temptation to port these given that there is that whole bottom section is alive too. A proper port shape could look real tasty on these. I got these for 100 bucks. Does anyone know the year or have any info?
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That is 4.17 cu ft. SB34NRX75-6 Vas is 260 L which is 9.17 cu ft. Qts .4 Fs 19 hz
I think your bass response will be wimpy. You should look for a driver with a lower Vas. Or build a bigger box. An eminence Deltapro-12a Vas 2.89 cu ft, Qts .35 Fs 51, suggested vented boxes are 1.2 - 3.0 cu ft. The small sealed cab has volume 1 cu ft F3 of 120 hz and watt limit of 300. Low cut filter >18 db/octave 150 hz required to not exceed Xmax. Deltapro-12a suggested large vented box is limited to 150 w, 24 db/octave low cut filter of 50 hz required. Vb is 3.0 cu ft and F3 is 60 hz. Single port diameter is 4.0" and length is 3.0". The cabinet specs are a link off the driver datasheet at eminence.com .
The ports, I would hide them behind the grill. You can use 2 ports instead of 1 if you match the area.
I too am nervous about bulding a box. No electric carpenter tools but a sabre saw, and only a door for a worktable. I've had 4 drivers for 18 months and no wood cut yet. I hate buying gadgets from the country that got me drafted.
passive 3 way crossovers have a lot of $20 components. Active requires running 2 or 3 amps all the time. There are tweeters that will take down to 1000 or 1200 hz pretty easily. I'm listening now to some RX22 CDs very pleasant, but for the new "uglyson" I bought N314T-8. The SP2(2004) has too much pawn shop value, visible through the windows and predessor SP2-XT were stolen.
I think your bass response will be wimpy. You should look for a driver with a lower Vas. Or build a bigger box. An eminence Deltapro-12a Vas 2.89 cu ft, Qts .35 Fs 51, suggested vented boxes are 1.2 - 3.0 cu ft. The small sealed cab has volume 1 cu ft F3 of 120 hz and watt limit of 300. Low cut filter >18 db/octave 150 hz required to not exceed Xmax. Deltapro-12a suggested large vented box is limited to 150 w, 24 db/octave low cut filter of 50 hz required. Vb is 3.0 cu ft and F3 is 60 hz. Single port diameter is 4.0" and length is 3.0". The cabinet specs are a link off the driver datasheet at eminence.com .
The ports, I would hide them behind the grill. You can use 2 ports instead of 1 if you match the area.
I too am nervous about bulding a box. No electric carpenter tools but a sabre saw, and only a door for a worktable. I've had 4 drivers for 18 months and no wood cut yet. I hate buying gadgets from the country that got me drafted.
passive 3 way crossovers have a lot of $20 components. Active requires running 2 or 3 amps all the time. There are tweeters that will take down to 1000 or 1200 hz pretty easily. I'm listening now to some RX22 CDs very pleasant, but for the new "uglyson" I bought N314T-8. The SP2(2004) has too much pawn shop value, visible through the windows and predessor SP2-XT were stolen.
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There are many things not very clear, so let's start
First the box, as wood is no good for box making for a woofer enclosure.
You should make it sound dead and sound proof. Then there's the grill and the frame, that makes it good only for the woofer, as the wavelengths in that range are longer than the objects they encounter.
Talking about Eminence drivers and the heavy duty drivers, probably not what OP wants but historically a box like that could accommodate a 12" coaxial... with a ready crossover available.
Other than that, I suggest to copy a project ready available, or go the hard way.
First the box, as wood is no good for box making for a woofer enclosure.
You should make it sound dead and sound proof. Then there's the grill and the frame, that makes it good only for the woofer, as the wavelengths in that range are longer than the objects they encounter.
Talking about Eminence drivers and the heavy duty drivers, probably not what OP wants but historically a box like that could accommodate a 12" coaxial... with a ready crossover available.
Other than that, I suggest to copy a project ready available, or go the hard way.
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Very nice wood. A shame not to use it.
If I had those I would be thinking about cutting some chipboard or MDF panels as a secondary layer and putting up with the lower internal volume you would get.
Personally I would use that vintage box for the bass and put a secondary enclosure on top, and being a vintage box I'd go for a vintage sound and a really old fashioned driver.
Unfortunately the boxes are not going to be wide enough to use a Mach3 woofer
https://www.parts-express.com/GRS-R...KGbJHMFZla6JqmcZZBO_VvW5kMgN9FLP4KHWtAN79q7dP
But perhaps somebody could advise on a similar woofer in 12 inch?
If I had those I would be thinking about cutting some chipboard or MDF panels as a secondary layer and putting up with the lower internal volume you would get.
Personally I would use that vintage box for the bass and put a secondary enclosure on top, and being a vintage box I'd go for a vintage sound and a really old fashioned driver.
Unfortunately the boxes are not going to be wide enough to use a Mach3 woofer
https://www.parts-express.com/GRS-R...KGbJHMFZla6JqmcZZBO_VvW5kMgN9FLP4KHWtAN79q7dP
But perhaps somebody could advise on a similar woofer in 12 inch?
Thank you for the response.
I do not intend to use the grills at all.
I do intend to add a layer of 3/8 plywood or mdf to the internal surface and make piece to glue in all the corners ( using kreg pocket screws).I should have been more clear about some of those intentions but did not want to write to much in the 1st post. This will be a journey. I also will have an mdf box to isolate the mid & tweeter or mid only if I go the path of seperate tweeter box. I also can make a box for the mid tweeter and use all the space in the vintage enclosure for woofer. I do understand that the enclosure needs additional material inside for a proper strong box and that that also reduces my volume to work with. So at this phase I am deciding the path more than the actual drivers but also taking a look at driver possibilities. I really am leaning towards a tower of multiple boxes. I can build my own boxes. I will even raise the humidity to 65% for several days before using the pocket screws just to ward off damage to the original wood. I am looking at the Gema from Madisound and many other designs and look forward to the crossover design challenge.
Thank you for the response.
We are very much on the same page. I am thinking of this constantly now and given that this will replace my main towers the idea of Vintage box woofer only and build box for mid(s) tweeter is winning. This is in my main theater room and will become my main speakers so not going to go the path of Vintage sound. I am shooting for reference path to listen to all genres and movies. I do have a high power twin 15" subwoofer system. So the Woofers need only play clean to 45ish to be crossed by sub at 60hz. Maybe I need to give up on the 12 and move to a 10 woofer. My internal volume after reinforcement and 1.25 thick baffle and rear panel is about 3.2 cuft..
Gema is one of the 3 Way kits they sell. Pretty much a 3 way in a very similar style box. Lead sheets LMAO nope
Got front and rear baffle inner panels done. these will be glued to an exterior panel making the front and rear 1.25 thick. The rendering is for the SB 12" Woofer and the Morel Hybrid Tweeter Mid. Still undecided but getting stuff done.
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Leaning towards this:
https://www.madisoundspeakerstore.com/approx-12-woofers/sb-acoustics-sb34nrx75-6-12-woofer/
https://www.madisoundspeakerstore.c...5-8-6.5-woven-carbon-fiber-cone-woofer-8-ohm/
https://www.madisoundspeakerstore.c...lassic-advanced-tweeter-1-textile-dome-8-ohm/
That 12 is supposed to be good for a sealed cabinet or ported and in the range of my cabinet volume.
I would build a seperate box for the tweeter or tweeter & mid. The tweeter alone in a box was what I was shooting for originally. The mid needs very little volume. There is another version of the mid on sale which require 2 but give me more range wattage wise. I could do TMMW or MTMW. What are your thoughts?
https://www.madisoundspeakerstore.com/approx-12-woofers/sb-acoustics-sb34nrx75-6-12-woofer/
https://www.madisoundspeakerstore.c...5-8-6.5-woven-carbon-fiber-cone-woofer-8-ohm/
https://www.madisoundspeakerstore.c...lassic-advanced-tweeter-1-textile-dome-8-ohm/
That 12 is supposed to be good for a sealed cabinet or ported and in the range of my cabinet volume.
I would build a seperate box for the tweeter or tweeter & mid. The tweeter alone in a box was what I was shooting for originally. The mid needs very little volume. There is another version of the mid on sale which require 2 but give me more range wattage wise. I could do TMMW or MTMW. What are your thoughts?
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I'm still not sure what you're doing. Do you intend to attach the plywood, or MDF, to the sides and bottom? I'm puzzled by 'the piece to glue in all the corners' with pocket screws. Can you sketch something which shows this?
Sure. I intend to use a layer added internally of 1/2 in plywood to sides and bottom. The top will be mdf 3/4 that fits into top space flush with what is there now & use edge glued hardwood glued to that mdf panel. Similar treatment for front & rear baffles. I will use a central horizontal plywood brace &a vent pipe that can easily be closed. The single 12 in the vintage enclosure puts it happy w displacement sealed or vented. I will just have to take pictures of the pieces getting pocket screws, and I took note below of not using those. Because of the way these are built I think some strategically placed screws are needed.
I think you're courting a problem with the idea of adding a layer of plywood to the interior IF you're planning on glueing/screwing the plywood to the solid wood. Plywood is (relatively) inert, solid wood isn't. If you made an interior box to fit inside, but not attached to, that lovely looking cabinet, you'd be okay. Alternatively, accept you'll have a 'leaky' box (Bagby's woofer/passive crossover design spreadsheet allows for that setting), or use a woofer for a closed system and add an aperiodic vent which would work in conjunction with the leaks. You might also rethink the MDF top and use solid wood as again MDF is (relatively) inert while those large sides and bottom are going to move with humidity. And a finish only slows down the abortion/lose, but won't eliminate it.