Thanks for the clarification. I'll go 3/4" ply everywhere. Keeping the baffle width constant, will, of course result in a .25" "volume" reduction inside the wings. I assume that is OK.
Full disclosure: I have lots of 3/4" ply leftover from building new kitchen cabinets.
Full disclosure: I have lots of 3/4" ply leftover from building new kitchen cabinets.
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That does make the space from the back of the magnets to the wings a bit tighter but as long as there is some clearance you are good.
Nice to have surplus 3/4in ply.
I have always wanted to build a tapped horn subwoofer… 🙂
Nice to have surplus 3/4in ply.
I have always wanted to build a tapped horn subwoofer… 🙂
Wow!....just found this for the first time.....amazing design.....i'm building it for sure!!!!!!! thx for sharing
For what it's worth, these speakers are well worth all the effort. I bought the flat pack, I think mine were 3/4 inch.
Russellc
Thanks Russellc. I am not a woodworker but I can see that there are a lot of pieces to this speaker and having a CNC flatpack is well worth the time and materials saved for a perfect fit.
OTOH, those who have spare plywood lying around have a good argument to DIY.
I have been asked if I can sell the digital plans so folks can CNC locally. Sorry can’t do that.
OTOH, those who have spare plywood lying around have a good argument to DIY.
I have been asked if I can sell the digital plans so folks can CNC locally. Sorry can’t do that.
I have sworn off building anymore speakers but something keeps drawing me back to this thread .... 😀
Lucky for me I have a few sheets of Lowes birch ply in 3/4" to work with and the right tools on hand, drill press and hole saw or router and guides to do all the cutouts, table saw, etc...just to busy working on our remodel and have to finish up outside then build new cabinets first, a lot of them, more than most houses and this is an RV but everything is custom built ins, no other real options. I can probably talk my wife into letting me practice on the speakers first though😉
I will use up the ply I have on hand as switching to lower cost per sheet but better quality ply made in Vietnam, cool eh!!!
I will use up the ply I have on hand as switching to lower cost per sheet but better quality ply made in Vietnam, cool eh!!!
Just an inquiry…..has anyone used these woofer instead?
https://www.parts-express.com/6-1-2-Poly-Cone-Woofer-4-Ohm-299-609?quantity=1
Higher QTS, lower FS, more xmax and cheaper to boot. Not a money saving question but more about performance. I understand that these are labeled as ‘buyouts’ so to use them in a commercial kit design, it becomes close ended. BUT if I’m correct these are the PE B52 speaker woofers so not sure they’re going anywhere any time soon
Thoughts?
https://www.parts-express.com/6-1-2-Poly-Cone-Woofer-4-Ohm-299-609?quantity=1
Higher QTS, lower FS, more xmax and cheaper to boot. Not a money saving question but more about performance. I understand that these are labeled as ‘buyouts’ so to use them in a commercial kit design, it becomes close ended. BUT if I’m correct these are the PE B52 speaker woofers so not sure they’re going anywhere any time soon
Thoughts?
Mayhem,
I used those same buyout woofers in the original one I made out of cardboard 8 years ago. They work great - except that if you want to use my passive crossover for the XSD, they won’t work because they are 4ohms. But actually very similar on performance. I don’t think the 8ohm GRS are any less capable. If you plan to go with active DSP as a crossover then they can work well. How would you wire 8 of them to get a good impedance though. Maybe two in series across the duct for 8ohms x 4 sets wired in series parallel for nominal 8ohms.
I used those same buyout woofers in the original one I made out of cardboard 8 years ago. They work great - except that if you want to use my passive crossover for the XSD, they won’t work because they are 4ohms. But actually very similar on performance. I don’t think the 8ohm GRS are any less capable. If you plan to go with active DSP as a crossover then they can work well. How would you wire 8 of them to get a good impedance though. Maybe two in series across the duct for 8ohms x 4 sets wired in series parallel for nominal 8ohms.
for 8 i'd wire them like a guitar cab.....2 parallel groups of 4 drivers in series for a nominal 8 ohms. I don't want to do DSP on this though so maybe i'll keep it text book if you don't see any real advantage to using them over the GRS.
A question on the baffle tilt…..was this a primary power/polar response feature and was the angled baffle compared to a perpendicular approach?……my listening distance is around 11 ft and seated ear height would still remain on almost the same primary horizontal axis.
Tilt was mostly to give stability for the speaker so that it doesn't tip forward so easily. It does help give the tweeter some time delay to match the acoustic center of the mid range.
If you look at the measured phase, it is flat between the mid and tweeter, meaning they are time-aligned.
If you look at the measured phase, it is flat between the mid and tweeter, meaning they are time-aligned.
Thanks X.....the more i look at it, the more i like the look of the tilt.....leave well enough alone i think. LOL
Woofers are ordered. I'm going to do some enclosure changes though as i'm not a fan of the screws holding in the side panels nor a fan of baffle resonance potential when using ribbons or planars......the light diaphrams of these drivers can be drastically impacted with droning resonance during complex music passages. The SLOB bass module will be stand alone and the the front baffle and frame will be stand alone and slide away from the SLOB....this will facilitate access to the SLOB drivers and eliminate contact and remove any baffle resonance. The planar will have it's own insert baffle will rubber well couplers so reduced and isolated contact from the mid driver.
Woofers are ordered. I'm going to do some enclosure changes though as i'm not a fan of the screws holding in the side panels nor a fan of baffle resonance potential when using ribbons or planars......the light diaphrams of these drivers can be drastically impacted with droning resonance during complex music passages. The SLOB bass module will be stand alone and the the front baffle and frame will be stand alone and slide away from the SLOB....this will facilitate access to the SLOB drivers and eliminate contact and remove any baffle resonance. The planar will have it's own insert baffle will rubber well couplers so reduced and isolated contact from the mid driver.
My thinking is just the opposite. I want to glue the entire thing together...everywhere. To facilitate removal of the woofers, I propose drilling holes in the wings, just large enough for a long screwdriver to reach the front screws (the back ones appear easy to reach). See attached showing the woofer array overlaid inside the wings.
This results in holes in the wings (probably 1/4" each in diameter). I see two options at the moment:
1. Leave them open provided the sound waves don't care and the "air leakage" thru them won't matter.
2. Put plastic plugs in them.
This results in holes in the wings (probably 1/4" each in diameter). I see two options at the moment:
1. Leave them open provided the sound waves don't care and the "air leakage" thru them won't matter.
2. Put plastic plugs in them.
Attachments
Make sure it is air tight between the wings / baffle / woofer box. Leaks will destroy the bass extension and power. Maybe you are thinking of what Linkwitz did to separate Z baffle woofer from the top on LX521?
Note that the woofers are opposed drive - meaning they are force cancelling. The only vibration is possibly from the pressure generated by the air being pushed out through the wings. 3/4in panels mounted to square ledgers is very sturdy and I have not had issues with vibrations from the woofer affecting the tweeter or mid. Look at the harmonic distortion spectrum. It is very clean and circa -50dB through the range for 1W drive (2Vrms). That’s about 89dB SPL (same as middle of dance floor ina nightclub). You are welcome to make it now we you like but just telling you I am not noticing any problems from mechanical vibrations (except woofer baskets which need Noico).
Passive/Active combo for best results, budget, etc idea(s). I have drawn out numerous layouts and this one seems best in many ways as I prefer less than more signal manipulations.
Using 8" woofers so I have to design a passive for them or use active or DSP for xover.
I have the items on hand except Active Xover or DSP nor passive components, amps I have at least for now are not balanced.
WiiM Pro Plus, SPDIF out to Topping V70 Velvet DAC.
Line out xkit active 2-way crossover.
High out to amp 1 then out to 2-way passive to tweet/mids using XSD design.
Low out to amp 2 to woofers.
Balanced line out of Topping DAC, changed to single ended to Sub with DSP.
Option, barely more cost.
xkit 3-way active using low out to drop off woofer output to where subs take over but still have Sub with DSP.
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Other ideas include a 3 or 4 channel DSP before DAC(s) but I prefer to not have multiple analog to digital and back two or more times.
Or, A DSP with very good DAC, not sure I can afford anything that would be worth it, not sure the MiniDSP FLex 8 DAC would be up to par with the Topping either. If it is indeed an excellent option I could skip all passive and go all active as have several 3-6 channel amps to play with.
----------------
I know Viet recommends all passives for the XSD and considering it but I also know I am faced with a difficult space to work with being in an RV and will end up testing several diffent speaker topoligies to find the best which I hope are the XSD's, if so I could then build the mid/woofer passives.
Thanks, let me know your thoughts, ideas, recommendations, please. I hope to finally build mine this summer or maybe late spring, tired of waiting!
Rick
Using 8" woofers so I have to design a passive for them or use active or DSP for xover.
I have the items on hand except Active Xover or DSP nor passive components, amps I have at least for now are not balanced.
WiiM Pro Plus, SPDIF out to Topping V70 Velvet DAC.
Line out xkit active 2-way crossover.
High out to amp 1 then out to 2-way passive to tweet/mids using XSD design.
Low out to amp 2 to woofers.
Balanced line out of Topping DAC, changed to single ended to Sub with DSP.
Option, barely more cost.
xkit 3-way active using low out to drop off woofer output to where subs take over but still have Sub with DSP.
----------------
Other ideas include a 3 or 4 channel DSP before DAC(s) but I prefer to not have multiple analog to digital and back two or more times.
Or, A DSP with very good DAC, not sure I can afford anything that would be worth it, not sure the MiniDSP FLex 8 DAC would be up to par with the Topping either. If it is indeed an excellent option I could skip all passive and go all active as have several 3-6 channel amps to play with.
----------------
I know Viet recommends all passives for the XSD and considering it but I also know I am faced with a difficult space to work with being in an RV and will end up testing several diffent speaker topoligies to find the best which I hope are the XSD's, if so I could then build the mid/woofer passives.
Thanks, let me know your thoughts, ideas, recommendations, please. I hope to finally build mine this summer or maybe late spring, tired of waiting!
Rick