Ever since I took my C-note kit from PE and slapped some PVC half rounds on it, I've been hooked on the sound of huge round overs and very minimal cabinet diffraction as far down as ~700hz. I think we have plenty of examples of how smaller round over overs (3/4" and under) can help some tweeters dispersion, but we need to go BIGGER. Deeper waveguides like ascilab that can hide the driver from baffle to a lower freq tend to sound a bit too narrow for my tastes, so I wanted to keep the tweeter waveguide small so it's lower region would still be quite wide.
Grimm has the big ole roundovers and I think the folks at Grimm are onto something with their LS1. To quote Amir in his LS1 review.
This is something I experienced as well with my little prototype. Honestly the smoothest sounding speaker I have heard were my ugly pvc c-notes (I did use active filtering so not really a c-note).
Not to ramble on too much but my theory on how diffraction manifests subjectively is a reduction in sound stage clarity. I find sound stage/imaging/what have you tend come from spatial cues in the music that have decay, not so much from percussive transients. I feel these longer decay sounds be it reverb tails, synth pads, droning guitars, etc... tend to resemble noise more than other aspects of music. When I play generated noise samples in REW through my speakers with diffraction issues, I find that you can sometimes hear a phaseyness from the edges interaction, I believe this phaseyness is imparted on the decayed signals in music, thus the degradation in stereo spatial effects. I constructed a large 3 way last year that looked like an ATC speaker, so hard baffle edges and offset tweeter and felt I could hear some localized sound to the edge furthest from the tweeter. Of course this could all be in my head and total nonsense but that's my theory on why I have pursued such a build as the one below. One problem I have had is how do I make this all look good? The Grimm LS1 and my protoype speaker sound amazing, but they don't really gel with me in the looks department. I think I settled on something I will be happy with.
Not quite done yet. My plan is to 3d print several attachable columns of round overs that near a 4" radius. I will join them together and apply a nice flat black finish to. I have yet to decide on how to attach them but I am leaning towards some magnets or dowels. Cabinet construction is MDF with some thing batlic birch ply for veneer. Cabinet fill is the fancy 1" denim insulation from PE.
The driver selection is the SB13 woofer for the mid, same as the Mechano23 but the 8ohm version for this tower speaker. I recently finished the mechano23 and found them to give me pretty much everything I want out of driver reproducing the mid range, and they're cheap so why not. Tweeter is the ND25FW because it's the best tweeter under $50 and I can't find any faults with it's sound, gives me exactly what I want in HF reproduction. Incredible performance for the money and you can achieve amazing dispersion results with the right cabinet. Woofer is a Peerless SLS 10" sub. Cheap, lots of cone surface area, does well in my boxes dimensions. Plan is to develop both active and passive filtering the speaker, life will determine which one I can afford to run as I do contract live sound work and gigs are kind of sporadic and good DSP ain't cheap.
Next step is to hook up and learn the 3d printer I was gifted and print the round overs. Filter development should go quick after that.
Some more shots.
This shot has the old woofer hole, I was originally going to go with a Dayton RS225 but I was convinced to go with the peerless 10" instead by a friend, a good decisions I feel.
Gotta drill holes into these and mount some thread inserts for them to screw into.
Grimm has the big ole roundovers and I think the folks at Grimm are onto something with their LS1. To quote Amir in his LS1 review.
This is something I experienced as well with my little prototype. Honestly the smoothest sounding speaker I have heard were my ugly pvc c-notes (I did use active filtering so not really a c-note).
Not to ramble on too much but my theory on how diffraction manifests subjectively is a reduction in sound stage clarity. I find sound stage/imaging/what have you tend come from spatial cues in the music that have decay, not so much from percussive transients. I feel these longer decay sounds be it reverb tails, synth pads, droning guitars, etc... tend to resemble noise more than other aspects of music. When I play generated noise samples in REW through my speakers with diffraction issues, I find that you can sometimes hear a phaseyness from the edges interaction, I believe this phaseyness is imparted on the decayed signals in music, thus the degradation in stereo spatial effects. I constructed a large 3 way last year that looked like an ATC speaker, so hard baffle edges and offset tweeter and felt I could hear some localized sound to the edge furthest from the tweeter. Of course this could all be in my head and total nonsense but that's my theory on why I have pursued such a build as the one below. One problem I have had is how do I make this all look good? The Grimm LS1 and my protoype speaker sound amazing, but they don't really gel with me in the looks department. I think I settled on something I will be happy with.
Not quite done yet. My plan is to 3d print several attachable columns of round overs that near a 4" radius. I will join them together and apply a nice flat black finish to. I have yet to decide on how to attach them but I am leaning towards some magnets or dowels. Cabinet construction is MDF with some thing batlic birch ply for veneer. Cabinet fill is the fancy 1" denim insulation from PE.
The driver selection is the SB13 woofer for the mid, same as the Mechano23 but the 8ohm version for this tower speaker. I recently finished the mechano23 and found them to give me pretty much everything I want out of driver reproducing the mid range, and they're cheap so why not. Tweeter is the ND25FW because it's the best tweeter under $50 and I can't find any faults with it's sound, gives me exactly what I want in HF reproduction. Incredible performance for the money and you can achieve amazing dispersion results with the right cabinet. Woofer is a Peerless SLS 10" sub. Cheap, lots of cone surface area, does well in my boxes dimensions. Plan is to develop both active and passive filtering the speaker, life will determine which one I can afford to run as I do contract live sound work and gigs are kind of sporadic and good DSP ain't cheap.
Next step is to hook up and learn the 3d printer I was gifted and print the round overs. Filter development should go quick after that.
Some more shots.
This shot has the old woofer hole, I was originally going to go with a Dayton RS225 but I was convinced to go with the peerless 10" instead by a friend, a good decisions I feel.
Gotta drill holes into these and mount some thread inserts for them to screw into.
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