Excellent work, thank you for the report! Yes, the LC bass boost circuit makes a big difference. +5 dB at 45Hz.
Hello Friends need help I have the SB 15OB350 not the eminence woofer also I dont know the corossover how to make. If I use the SB woofer what change in crossover is needed. I really want to make this happen. Also if I use the crossover that Perry published with my SB what issues will I have
regards
anand
regards
anand
I want also to make a kind of walnut dipôles.
Plan is to use a 15ob350 a tw29txnb-8 either in the SB acoustic waveguide or a "somasonus" and a 8nmb420 as midi.
@perrymarshall do you think a single 15ob350 is enaught in a 70sqm living room to have a -3db at 30 ?
Plan is to use a 15ob350 a tw29txnb-8 either in the SB acoustic waveguide or a "somasonus" and a 8nmb420 as midi.
@perrymarshall do you think a single 15ob350 is enaught in a 70sqm living room to have a -3db at 30 ?
I'm not aware of any, but this design could substitute the 15OB350 without much modification, and the substitution would be an improvement in Xmax:
https://psma-website-assets.s3.amazonaws.com/live_edge_beryllium_dipoles.pdf
https://psma-website-assets.s3.amazonaws.com/live_edge_beryllium_dipoles.pdf
Moved into a townhouse. Dealing with thin walls got me interested in some dynamic driver dipoles. Figure worth a try to minimize annoying the neighbors with bass and make for a different (and thus fun for me) project. Have you done any work with an analog (active or passive) crossover on the input side to the amps?
Also, any investigations in using a similar rear-firing tweeter as the front firing? Given the reflective purpose of the rear, would matching voicing matter that much or provide any improvement?
-tom
Also, any investigations in using a similar rear-firing tweeter as the front firing? Given the reflective purpose of the rear, would matching voicing matter that much or provide any improvement?
-tom
Have not explored analog active crossovers.
Almost all of my dipole designs have used coax drivers, so the closest I come is choosing a horn tweeter on the back that has a similar frequency response curve. The affordable PRV WG175Ph tweeter I use on many of my dipoles seems to match pretty well.
Almost all of my dipole designs have used coax drivers, so the closest I come is choosing a horn tweeter on the back that has a similar frequency response curve. The affordable PRV WG175Ph tweeter I use on many of my dipoles seems to match pretty well.
Why you don't think a midrange is needed. If i want to avoid cone brakeup and match directivity i'm not sure i can avoid it.
That said, i'm not familiar with OB and i can imagine that what's true for conventional speaker may be different for OB.
By the way, you have used a 8" coax midrange in the "live edge dipôle" instead if simple compression or tweeter.
My idea was to make a kind of a mix between the live-edge the walnut (and bitches brew woofers)
The 15OB350 and the SB 29 Waveguide tweeter will match pretty closely in directivity. Crossover at 1600.
The Live Edge Dipoles do use an 8" coax midrange: https://www.diyaudio.com/community/...ker-design-competition-updated-design.405104/
You can use the 15OB350 instead of the 18" Eminence in the Live Edge Dipole design and the two drivers should perform similarly.
The Live Edge Dipoles do use an 8" coax midrange: https://www.diyaudio.com/community/...ker-design-competition-updated-design.405104/
You can use the 15OB350 instead of the 18" Eminence in the Live Edge Dipole design and the two drivers should perform similarly.
@perrymarshall: Perry, here’s a thought experiment for you 😉. Suppose you were starting with a clean sheet of paper and your aim was to design an OB speaker that was better than the BB, and lets also say you were not too constrained by the cost of the drivers. What combination of drivers might you pick?
Regarding the woofers, Peter Lyngdorf has said that the new 10” Purifi woofer is the lowest distortion driver ever produced and having heard some speakers that incorporate them I am fully prepared to believe it. I’ve seen the view expressed that the Purifi drivers do indeed have exceptional performance relative to their size, but that the same level of performance could be achieved by choosing a bigger driver. I do however wonder about that; when developing their studio monitors these guys tried out various woofers to go with the Blies-ma tweeters and mid-range that they had already settled on. None of ones they tried could match the quality of sound of the Blies-ma drivers, that is until they tried the 8” Purifi woofer. https://www.presentdayproduction.com/
The sensitivity of the Purifi 10” is quite low and I don’t like the idea of throwing away the presumed sensitivity of the tweeter / mid-range. Mitch Barnett mitigated that problem by using a lower gain amp on the tweeter of his 2 way active system. That seems like an elegant solution to me.
One last thought re the Purifi 10” and its a prediction; when Steinway Lyngdorf eventually upgrade / replace the Model B, I will be very surprised indeed if the woofers they choose are not Purifi ones . . .
Anyway Perry, next time you have some time to kill perhaps you might idle your time away by thinking about my thought experiment ?
Regarding the woofers, Peter Lyngdorf has said that the new 10” Purifi woofer is the lowest distortion driver ever produced and having heard some speakers that incorporate them I am fully prepared to believe it. I’ve seen the view expressed that the Purifi drivers do indeed have exceptional performance relative to their size, but that the same level of performance could be achieved by choosing a bigger driver. I do however wonder about that; when developing their studio monitors these guys tried out various woofers to go with the Blies-ma tweeters and mid-range that they had already settled on. None of ones they tried could match the quality of sound of the Blies-ma drivers, that is until they tried the 8” Purifi woofer. https://www.presentdayproduction.com/
The sensitivity of the Purifi 10” is quite low and I don’t like the idea of throwing away the presumed sensitivity of the tweeter / mid-range. Mitch Barnett mitigated that problem by using a lower gain amp on the tweeter of his 2 way active system. That seems like an elegant solution to me.
One last thought re the Purifi 10” and its a prediction; when Steinway Lyngdorf eventually upgrade / replace the Model B, I will be very surprised indeed if the woofers they choose are not Purifi ones . . .
Anyway Perry, next time you have some time to kill perhaps you might idle your time away by thinking about my thought experiment ?
You bet. I’d use six or eight Purifi 10” woofers on each side and the combo would have mid-90s SPL. Match them to a Bliesma T34 fitted with a waveguide and you’d have one serious @@@-kicking system.
Yeah that makes sense. Even without a waveguide the T34 Be is usable down to 1300 hz and the Purifi 10” looks good up to 2000hz, so a reasonable window to play with. I bet even just 2 x 10” per side would work pretty well . . .
2 10” Purifi and a T34 + WG in a “Flanagangster” configuration would work very well.
...
The Flanagangsters
A Heretical Reflex+Open Baffle Hybrid
Constant Directivity, 96dB SPL, 300 Watts, 35Hz-20KHz
Crafted from Live Edge Wood
(re-posted from https://www.diyaudio.com/community/threads/ultimate-open-baffle-gallery.123512/post-7216744)
A Heretical Reflex+Open Baffle Hybrid
Constant Directivity, 96dB SPL, 300 Watts, 35Hz-20KHz
Crafted from Live Edge Wood
(re-posted from https://www.diyaudio.com/community/threads/ultimate-open-baffle-gallery.123512/post-7216744)
Interesting comparison here, not least because I already own a slightly smaller JC horn, the ES1200 . . . .
https://josephcrowe.com/blogs/news/bliesma-t34b-4-on-waveguide-no-2439
It's sure be fun to visit you at your place. Books, tea and loudspeakers. And a sub in a barrel cask!
I built a pair with the 150B30 and the Peerless by Tympany XT25-TG30-40 in a Wavecore waveguide.
I used Water Oak Slabs.
I also used xmachina to design the initial crossovers and finished up in Vituixcad.
I used Perry's bass boost circuit: the 680uF capacitor and 22 mH inductor.
The woofer is a bit more sensitive than the tweeter in the waveguide, so the 24 ohm resistor pads it down a bit.
They sound great. Very natural.
I used Water Oak Slabs.
I also used xmachina to design the initial crossovers and finished up in Vituixcad.
I used Perry's bass boost circuit: the 680uF capacitor and 22 mH inductor.
The woofer is a bit more sensitive than the tweeter in the waveguide, so the 24 ohm resistor pads it down a bit.
They sound great. Very natural.
Gorgeous!!! I love your implementation. I'd love to see measurements and anything else you think we'd find interesting.