Why spend all of that money on a driver only to phase shift it with EQ?………..not sure how else to express this misnomer that the listening crowd yields like a magic wand…….EQ is destructive……and digital EQ is FAR worse than analog.
A recession (or wg) for the dome mid will introduce other kind of diffraction problems above 3kHz (check Volt response) Making a stepped baffle to correct timing isn't easy either, or esthetic.... and would require several proto iterations.
Choose your poison, that's it.
Choose your poison, that's it.
Check the look... 🙂 My version of "pyramid head" with added bass bins....I'm thinking about this for a longer time and for this black friday I bought two little buggers SB12CAC and SB12MNRX to try to complement already existing 3 way protoype....
This is CAD model of rather large 4 way with two SB23NRX in 30+30 litres bass bins, and SB17CAC, SB12CAC and SB26CDC in 40 litres pyramid...
With very thick walls speaker dimensions would be 35 x 45 x 120 cm...or 70 cm height for bass department and 50 cm for upper drivers....
hifijim, you will have smaller pyramid with big bass units and you should somehow harmonize dimensions to have soft transition between middome and bass bins to keep diffraction low...
This is CAD model of rather large 4 way with two SB23NRX in 30+30 litres bass bins, and SB17CAC, SB12CAC and SB26CDC in 40 litres pyramid...
With very thick walls speaker dimensions would be 35 x 45 x 120 cm...or 70 cm height for bass department and 50 cm for upper drivers....
hifijim, you will have smaller pyramid with big bass units and you should somehow harmonize dimensions to have soft transition between middome and bass bins to keep diffraction low...
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………and in such my opinion and experience that dome mids are only suitable for near to midfield monitoring applications………..ATC uses steep filters to 3.5k but run the low end lower than most as there’s less issues to contend with
Now it's starting to look uneasy on the eyes. Something about the proportions. I'm no architect or interior designer, that part is clear. But I think it's something about the proportions.
Now we're starting to look like Revel Ultima Salon 2 baffle... which I think would be easier to 3D print or alu CNC, at least for the upper 3 drivers:
They really the ball out of the park with this design:
30 years ago. Quad amped. EQ'ed.
Now we're starting to look like Revel Ultima Salon 2 baffle... which I think would be easier to 3D print or alu CNC, at least for the upper 3 drivers:
They really the ball out of the park with this design:
30 years ago. Quad amped. EQ'ed.
Diffraction covers the entire frequency range and has different effects at different frequency ranges. The effect of the baffle and cabinet on how the speaker radiates sound is only ever insignificant in the nearfield. The entire sound balance of the speaker is impacted by this. The Bliesma metal dome mid's radiate quite differently from the ATC or Volt silk domes, this causes the drivers to be more sensitive to baffle and cabinet interaction.
The value is in seeing how the choices made determine what is possible. A deep waveguide or a cabinet with high diffraction loss creates a more strongly tilted soundpower and in room response. This may or may not be what is wanted and either can be made to sound good. It is not possible to undo the effect that increasing directivity from the speaker has. It comes back to what is the use case and design goal for the speaker.
A very nice, succinct statement of the importance of managing diffraction, both low frequency (baffle step and baffle gain), and high frequency (peak/valley ripples and secondary sound sources). Well said.
Yes, this is a very important point. Changing the crossover has limited impact on directivity, and EQ of course has none. In a DIY speaker project, when we reach the stage where we measure our driver responses in the finished cabinet and start designing the crossover, we are well past the point where we can significantly change the directivity of the speaker.
Diffraction, dispersion; tomayto, tomarto; potayto, potarto...
How the sounds, as they radiate into 3D space, are set in stone (veneered MDF?) once the cabinet is made...
How the sounds, as they radiate into 3D space, are set in stone (veneered MDF?) once the cabinet is made...
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As someone who has spent all that money (WO24, M74T, T25B) for their next (last?) build, I'd love elaboration on this. Both aspects (EQ destructive and digital EQ worse) please. Perhaps it warrants a separate thread to discuss?
Also, it's very clear to me, based on this thread alone, that I'm in over my head for my next build. I'm pleased with that because the learning is half the fun and I've got lots of time.
Nah, those negative eq comments are just boomer talk... 😁
Modern digital measurement possibilities and digital eq has revolutionized loudspeakers and roomintegration, at least for me. 😃
Modern digital measurement possibilities and digital eq has revolutionized loudspeakers and roomintegration, at least for me. 😃
I am about to make tests with a baffle covered with melamine foam and alternatively with wood/mdf. Final baffle will be covered with fabric for pleasing visual design.
Exchanging all baffle or parts with melamine/wood/other open cell foam material (several sheets?) will allow adapting of baffle influence, at least that's my idea ...
And everyone else too. This is why we have speakers the size of a hotbog or hamburger that sounds far better than they could do in the past, with real extension down to 50Hz and up to 16KHz, of various sizes to deliver with required SPL for the intended audience (desktop, kitchen, bedroom, study, outdoors)
Did we really put speakers on the floor 50 years ago?
If so, things have come a long way, for the better:
If you want to apply these technologies to bigger speakers (1/4 cu foot to 14 cu foot) they all benefit- and the benefits are still there. Whether the mass market to pay for it is another matter. But since you DIY for yourself- who cares? eg. frequency slope dependent limiters means you'll NEVER blow your surrounds or voice coils again, or integrated boost regulators that are quick to react such that they can boost the voltage li-po cells such that full power remains is available for every bass beat, but drops back down in between, which gives stupendous battery life.
Few people want a video tape player. Unless of course, you would like some nostalgia (or proud luddite, or have a bit of progresso-phobia).
But once you are shown a modern technology, it's like magic... sometimes to the point of alienating.
But anyone who has been talking about audio since the days of the BBS, will recognize it's amazing what we can learn/share now...
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I'm only on the 2nd page of this thread. However, I wanted to throw out my example of a split cabinet and trapezoidal baffle. The midrange/tweeter cabinet sits on the 2 cu ft woofer cabinet. I use 1/4" Sorbothane pads between the two cabinets. No other fasteners.
I'm running everything active with a miniDSP 4x10HD. Crossovers are at 400Hz and 3000 Hz. Here is the latest directivity measurement I made.
The drivers I used were a Vifa set I picked up in the mid-aughts (P21, P13 and D27TG). I work really slow. I recently purchased four SB29NRX75-8 10 woofers to upgrade, two for each bass box. They will be sealed and I'm shooting for about 50 Hz without any EQ since subwoofers will be part of the system.
I'm running everything active with a miniDSP 4x10HD. Crossovers are at 400Hz and 3000 Hz. Here is the latest directivity measurement I made.
The drivers I used were a Vifa set I picked up in the mid-aughts (P21, P13 and D27TG). I work really slow. I recently purchased four SB29NRX75-8 10 woofers to upgrade, two for each bass box. They will be sealed and I'm shooting for about 50 Hz without any EQ since subwoofers will be part of the system.
See you stepped in 💩 there…….i’m GenX with over 40 years of practical experience and…..well……as far as the ear/brain mechanism goes……..that’s a few million years of evolution there. Music is organic and analog in its origin……the farther away from that you go, the worse for it. But hey, all you millenials need to do is get high and have some Cheetos…..everything’s sounds groooooooooooooovy. 😏
I'm Gen X too; we're all different and that's OK.
But only the only "pure analog" signal path I've ever embraced is the SL1200mk2- and that was for the acetates, limited releases and obscure releases that never made it to CD. Oh, and a little vinyl noise and lower stereo separation is a nice thing on headphones IMHO. But even my childhood heroes now run Ableton Live on their laptops and share their tracks on Soundcloud, now longer tapes.
But to suggest digital is somehow destructive is to not fully appreciate sampling theorem, I believe.
From the people who brought us .FLAC :
But only the only "pure analog" signal path I've ever embraced is the SL1200mk2- and that was for the acetates, limited releases and obscure releases that never made it to CD. Oh, and a little vinyl noise and lower stereo separation is a nice thing on headphones IMHO. But even my childhood heroes now run Ableton Live on their laptops and share their tracks on Soundcloud, now longer tapes.
But to suggest digital is somehow destructive is to not fully appreciate sampling theorem, I believe.
From the people who brought us .FLAC :
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I was born in 1959, got interested in audio/speakers in 70s and made kit speakers and read magazines (remember those?). I started buying CDs in mid 90s but never abandoned vinyls. My diy hobby was revolutionized 10+ years ago after purchasing a mic+REW and minidsp 4x10HD! Now most of my speakers have multichannel dsp, classD amps and source is digital streaming!
I have never been more satisfied with home listening, but live acoustic concerts are the best I know. My kids have played various instruments at home too, piano, violin, sax, flute, guitar etc.
I have never been more satisfied with home listening, but live acoustic concerts are the best I know. My kids have played various instruments at home too, piano, violin, sax, flute, guitar etc.
I’m also GenX with over 40 years of practical experience and…..well……as far as the eye/brain mechanism goes……..that’s a few million years of evolution there. Video is organic and analog in its origin……the farther away from that you go, the worse for it.
This is why I am sticking with my CRT TV, these OLED 4k screens hurt my eye with that really bad harsh picture.
This is why I am sticking with my CRT TV, these OLED 4k screens hurt my eye with that really bad harsh picture.
Having 100% conviction for one solution and then using it everywhere denying any alternatives is just dumb. It's much more productive, and wise, to stay adaptive and understand when some solution works better than the other. Since speakers are bunch of compromises, locking to a particular solution wipes out about half of the design freedom and lowers propability for optimal outcome. It might appear something is better due to small sample size, so always keep optimistic view on things to maintain maximum flexibility and increase probability of optimal outcome.