For a guy like me who doesn’t need a driver to do much above 90db, and that’s actually with like 10db headroom, the bmr 2” is not the worst choice I could make in choosing a widebander. But there’s also the possibility of adding a small neo tweeter to play above 5khz right before the resonant modes start appearing. I wonder how the transient response of a 5/8ths soft dome would compare to a ribbon, planar, or amt. That’s saying that more than only a few people could tell the difference blindfolded from a tiny dome and a ribbon type transducer. That could also be an avenue for me to explore in getting everything into those premade black Dayton cabinets I like so much.
I’m quite good with fiberglass from my car audio interest and could easily fit the bmr 2” and tiny neo dome onto a 4.5” circle that fits the tweeter cutout and even point on axis if the response wasn’t already phenomenal from a tiny dome. But, the center to center spacing would still be far from a 1/4 wave at even a 2” c to c. This is fun.
I’m quite good with fiberglass from my car audio interest and could easily fit the bmr 2” and tiny neo dome onto a 4.5” circle that fits the tweeter cutout and even point on axis if the response wasn’t already phenomenal from a tiny dome. But, the center to center spacing would still be far from a 1/4 wave at even a 2” c to c. This is fun.
The Techtronics driver Erin measured does have decent low distortion, though. Around -50dB at 90dB 1m. I don't see a big jump where the resonant operation seems to start.
The jist of what @andy19191 and @planet10 are saying seems to be 'this is as good as they can get', right?
Perhaps line array is a very good build option for such drivers, sorting power handling and lowering distortion. Average of lobing might even be helped if each driver where rotated a little.
The jist of what @andy19191 and @planet10 are saying seems to be 'this is as good as they can get', right?
Perhaps line array is a very good build option for such drivers, sorting power handling and lowering distortion. Average of lobing might even be helped if each driver where rotated a little.
I’ve thought before about running 2x3 of the bmr 2” on the little Parts Express .04cf knockdowns I love so much. The high q of the 2” gets a little rowdy with 6 in .04cf but even with only three ~$25 they begin to become more realistic for more people spl wise, at least for a micro bookshelf like I’m going for here. 1/4 wavelength c to c is right at 7khz. I wonder how the polar world look, I don’t have any experience simulating arrays or clusters. A 3x6 cluster seems like it would reach darn close the limit of hearing with cabinet ear level and on axis.
There is a 1-3/4” bmr with a more pedestrian qts but I can’t find any measurements on it and those drivers seem like they can be all over the place performance wise. I enjoyed the 3.5” as a novelty when playing around with it in my .5cf cabinet with a 7” pr tuned in the very low 30’s. Volume limited to near field for sure at that tuning, but it was fun to listen to until I needed the cabinets for more official duties.
I haven’t played with the 3.5’s in at least two years but after seeing the measurements, I don’t have much urgency to make time to. I know very little about how the engineering goes to make those drivers work like they do but if the employment of the resonances lessened intermodulation, the 3.5” with it’s 5mm throw could be a decent competitor in the 3”-4” class. Unfortunately, it’s measurements are a dumpster fire…
https://hificompass.com/en/speakers/measurements/tectonic/tectonic-tebm65c20f-8
There is a 1-3/4” bmr with a more pedestrian qts but I can’t find any measurements on it and those drivers seem like they can be all over the place performance wise. I enjoyed the 3.5” as a novelty when playing around with it in my .5cf cabinet with a 7” pr tuned in the very low 30’s. Volume limited to near field for sure at that tuning, but it was fun to listen to until I needed the cabinets for more official duties.
I haven’t played with the 3.5’s in at least two years but after seeing the measurements, I don’t have much urgency to make time to. I know very little about how the engineering goes to make those drivers work like they do but if the employment of the resonances lessened intermodulation, the 3.5” with it’s 5mm throw could be a decent competitor in the 3”-4” class. Unfortunately, it’s measurements are a dumpster fire…
https://hificompass.com/en/speakers/measurements/tectonic/tectonic-tebm65c20f-8
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A 2" £1-10 driver is likely the commercial optimum. One can go large and more expensive to get some improvement but the use of resonances will always limit the achievable technical performance. About 20 years ago when there was more interest in bending wave speakers I attended an informal presentation of a large DIY/prototype in a medium sized lecture room. It sounded fine with percussion and one or two instruments (e.g. the inevitable Stimela) but the designer with a smile refused to play orchestral music.
Did you ever get an answer on this? Was wondering about using these drivers in a line array myself.. With a sub 2" C2C amd a combined 94db sensitivy with 48 in a line for under $800 seems like a pretty good deal no??
Well I just bought quads of old-stock 2" and 2.75" to try, at $2ea. Because the $30ea SB65 I had just tested is now out-of-stock in China. But back to the thread subject: how do these two drivers compare above 2khz?
SB65WBAC25-4 vs SB26STCN-C000-4
Aluminum annular-cone with soft dome-cap fullrange vs silk-dome tweeter, same maker, same price.
SB65WBAC25-4 vs SB26STCN-C000-4
Aluminum annular-cone with soft dome-cap fullrange vs silk-dome tweeter, same maker, same price.
I’m a beginner in diy speaker building. I’m heading down the ob route.
I’m beginning to think more and more that everyone’s hearing is different, and that what everyone calls good and better is different.
I’m a very average musician, gigged guitar and piano, who has played concert Steinway, Yamahas, and a few others. I’ve had a lovely baby grande in my living room for years. I get bored playing a bad piano in a few minutes. I can play a good piano for a while. With a top piano, I can play simple music for hours. All registers sound sublime. I have been at audio shows where there is a piano. And the feeling and sound of playing the bass specially, is so much better than any speaker. It’s not depth, or evenness of frequency, it’s the harmonic richness and alive soul and beauty of the sounds as they hit me. And no, there is no bass impact, it’s much more beautiful than that. For the highest piano register read the same.
I have owned AR9’s, stacked quad 57s, lowther compact 400’s with dx2’s in, linkwitz Orion’s and lx minis, fii f15’s open baffle, eclipse 510’s, I’ve sat in front of avantgarde trios for hours. I’ve sat in front of 100’s of other speakers at shows and in homes. Of all prices.
The ar9’s always sounded rubbish in my lounge.
The 4 speakers that stand out for me are the ar9’s in my girlfriend’s lounge, the quads, lowthers, and trios.
The most astinishin listening to music experiences I have ever had in hi fi were a Rolling Stones album through dl103, rb300, Lenco, tl12+, single quad,… ok computer into cd player then the same quad setup, ….the sound track to gladiator through the ar9’s, ….Sade through cd player quad306 croft pre gradient triangular shape small floorstanders, and top of the tree, a radio 3 live fm broadcast of two tenors in germany singing Mac the knife with a piano, through Sansui tu710 leak12+ my lowthers in exactly the right spot. Oh my god those men were in my lounge and magic happened!
I am coming to the conclusion that for me, and from the above, that the speed of a paper lowther and the way it can convey emotion is extraordinary. I sold the speakers because of occasional shout, and I wanted smaller. Silly me. The quads have the same speed (Martin Logan’s feel bloated when I heard them and no other electrostatic has matched the quads, though they are compromised in dynamics and frequency extremes, and their size.
I am realising that for me metal cones maybe are not fast enough. That crossovers remove some of the magic, that I need at least 5 listening rooms at home.
I dream of a speaker that can reproduce the treble and bass of a real top piano. Meanwhile, I think that everyone here is chasing their version of all I have said above. I’m amazed in my reading here how different everyone’s ways of getting there are. Just this thread! My magic is definitely other people’s poison on this thread.
I think planet Dave says it best here in terms of compromises, and I like mr Chang’s view on old full rangers and Chinese copycats doing maybe very good.
And here’s a funny thing, top guitarists sound like themselves no matter what guitar they play. I used to chase tone in my guitar pickups, when I should have been practicing. And one of my greatest musical experiences was listening to a virtuoso pianist make a crap out of tune piano sound like the best Steinway ever playing Chopin in a living room I was sitting in. Who says there’s no such thing as magic.
I’m beginning to think more and more that everyone’s hearing is different, and that what everyone calls good and better is different.
I’m a very average musician, gigged guitar and piano, who has played concert Steinway, Yamahas, and a few others. I’ve had a lovely baby grande in my living room for years. I get bored playing a bad piano in a few minutes. I can play a good piano for a while. With a top piano, I can play simple music for hours. All registers sound sublime. I have been at audio shows where there is a piano. And the feeling and sound of playing the bass specially, is so much better than any speaker. It’s not depth, or evenness of frequency, it’s the harmonic richness and alive soul and beauty of the sounds as they hit me. And no, there is no bass impact, it’s much more beautiful than that. For the highest piano register read the same.
I have owned AR9’s, stacked quad 57s, lowther compact 400’s with dx2’s in, linkwitz Orion’s and lx minis, fii f15’s open baffle, eclipse 510’s, I’ve sat in front of avantgarde trios for hours. I’ve sat in front of 100’s of other speakers at shows and in homes. Of all prices.
The ar9’s always sounded rubbish in my lounge.
The 4 speakers that stand out for me are the ar9’s in my girlfriend’s lounge, the quads, lowthers, and trios.
The most astinishin listening to music experiences I have ever had in hi fi were a Rolling Stones album through dl103, rb300, Lenco, tl12+, single quad,… ok computer into cd player then the same quad setup, ….the sound track to gladiator through the ar9’s, ….Sade through cd player quad306 croft pre gradient triangular shape small floorstanders, and top of the tree, a radio 3 live fm broadcast of two tenors in germany singing Mac the knife with a piano, through Sansui tu710 leak12+ my lowthers in exactly the right spot. Oh my god those men were in my lounge and magic happened!
I am coming to the conclusion that for me, and from the above, that the speed of a paper lowther and the way it can convey emotion is extraordinary. I sold the speakers because of occasional shout, and I wanted smaller. Silly me. The quads have the same speed (Martin Logan’s feel bloated when I heard them and no other electrostatic has matched the quads, though they are compromised in dynamics and frequency extremes, and their size.
I am realising that for me metal cones maybe are not fast enough. That crossovers remove some of the magic, that I need at least 5 listening rooms at home.
I dream of a speaker that can reproduce the treble and bass of a real top piano. Meanwhile, I think that everyone here is chasing their version of all I have said above. I’m amazed in my reading here how different everyone’s ways of getting there are. Just this thread! My magic is definitely other people’s poison on this thread.
I think planet Dave says it best here in terms of compromises, and I like mr Chang’s view on old full rangers and Chinese copycats doing maybe very good.
And here’s a funny thing, top guitarists sound like themselves no matter what guitar they play. I used to chase tone in my guitar pickups, when I should have been practicing. And one of my greatest musical experiences was listening to a virtuoso pianist make a crap out of tune piano sound like the best Steinway ever playing Chopin in a living room I was sitting in. Who says there’s no such thing as magic.
The best treble reproduction, to my ears, has always come from speakers with ribbon tweeters. Done right, I hear detail and delicacy in the highs that I don't hear from either full-rangers or dome tweeters.
A FR can't beat the high end tweeters in terms of resolution and (for most drivers) dynamics. However, there are drivers which are extremely capable, able to be xo'd very low and on top of that, are extremely cheap. The FRS 5 X reaches 30k (measurements of Klang+Ton, German DIY magazine), got a very good dispersion, good resolution and can be low xo'd. Downside: As mentioned, not very high max spl due to the small VC (14mm). I bought my last 6 ones for less than 10€ each but they are now still below 14€.
I remember reading Chick Corea saying an improperly setup piano, no matter the pedigree, can be a "real dog". I suppose he ought to have known about that. Consider yourself fortunate to have similar perceptions. To me, sounds are like flowers; many beautiful, all different.
~ 35 years ago I sold an audio oscillator to a fellow, who was telling me his speaker design won some contest, because it reproduced the sound of a piano better than all the rest. The only detail I recall is he said he used a first order crossover.
I spend most of my "music" time learning to play / sing, in a desperate attempt to uncover as much as I can of any latent talent / gift that I was just too lazy to pursue in my younger decades. I can actually perform (sort of) some stuff that in earlier years of my life I could only dream of doing. "it's never too late" or so they say; I certainly dont look the part, but that's not what seems to matter now.
I think it's good to have a few real acoustic instruments about the house, if only to compare reality against reproduced, from the vantage of ones own perceptions. Within the confines of whatever lounge you're in. If you have someone that can play them for you, even better.
I don't know why the forum didn't show me your quote/reply but anyway. I've used them from 500Hz in one case to 2,5k in another (replacement for a vintage cone tweeter). I plan to use them in one of my next projects from 1,5k up since I've got a bunch of woofers which are PERFECT up to 1,5k but drop fast after that. It will be a miniature version of the Visaton Zyklop.
:^)
Different genetic basis, where did you grow up, a noisy city or the quiet country, different levels of training & experience, taste, and to some extent budget.
And speakers in particular has a long ways to go. With modern technology the design of a loudspeaker is a collection of compromises.
dave
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That was alway the case but since modern speaker development, there are a lot less compromises to take on. I'm especially excited about the much increased possibilities uses of FR drivers!
But they usually do not go low enuff. The Decca London is special here, i heard them crossed at 1Khz to a paper 8”, an actual Decca prototype, i got to go at them and, at least at that time, nothing touiched them up top.
dave
Some struggle, certainly, but not all. Long ones like Apogee can go low - down to a few hundred Hz. The better short ones do fine too.
A Panasonic 6". I have a bunch of them laying around for ages, they aren't anything special but they behave perfectly up to 1,5k and then fade out without any resonances. Really easy to handle and they sound great. The downside is, they have a really ugly steel stamped basket, I have to come up with something to make them look decent. But both drivers look nice and the original design 'scaled down' would really fit to them.