I have SB29RDC, TW29RN-B and SB26ADC. I have compared them at 1780Hz 12dB/oct LR.
All of them are good, however....
It's not a good comparison at all.
-SB29 is not suited at all in such a large waveguide because top-end directivity matching is a no-go. Boost of the waveguide doesn't reach as far to the top-end as with a smaller tweeter.
-SB29 is a soft dome, so it will 'dampen' some of the detail. To be more precize: it's not a dome at all. It doesn't move as a piston.
-SB26ADC has lot's more power handling (so less power compression).
Regarding detail: TW29 wins of the SB29 especially in the bottom region,as seen in harmonic distortion plots. Around 4-5kHz, it also sounds more detailed.
Then, SB26 sounds more detailed than TW29. It has comparable 3rd harmonic distortion as to TW29, but 2nd harmonic is around 20dB less. That's a lot.
SB26ADC is the winner all day long. The only subjective thing I liked more on the SB29/TW29 is the slight raise in top-end on those. When I copied this behaviour using DSP over to SB26, it gained the pro's of both worlds and cons of none.
After having played a while with SB26ADC, I somewhat regret buying TW29. Still, compared to other manufacterers, TW29 is cheap. That makes SB26ADC stupid cheap, and the best buy I have ever done. Won't need another tweeter ever again.
I play loud sometimes, that's why I've been waiting for the SB waveguides for the SB26ADC for a long time now. However, I've never ran them into distorting anything close to what SB29 or TW29 do (they get nasty when played loud). I am seriously rethinking the idea of even needing waveguides for the tweeters at all (even dispersion characteristics are close enough to what I wanted).
Sorry for the long post, hope you will find it useful.
All of them are good, however....
It's not a good comparison at all.
-SB29 is not suited at all in such a large waveguide because top-end directivity matching is a no-go. Boost of the waveguide doesn't reach as far to the top-end as with a smaller tweeter.
-SB29 is a soft dome, so it will 'dampen' some of the detail. To be more precize: it's not a dome at all. It doesn't move as a piston.
-SB26ADC has lot's more power handling (so less power compression).
Regarding detail: TW29 wins of the SB29 especially in the bottom region,as seen in harmonic distortion plots. Around 4-5kHz, it also sounds more detailed.
Then, SB26 sounds more detailed than TW29. It has comparable 3rd harmonic distortion as to TW29, but 2nd harmonic is around 20dB less. That's a lot.
SB26ADC is the winner all day long. The only subjective thing I liked more on the SB29/TW29 is the slight raise in top-end on those. When I copied this behaviour using DSP over to SB26, it gained the pro's of both worlds and cons of none.
After having played a while with SB26ADC, I somewhat regret buying TW29. Still, compared to other manufacterers, TW29 is cheap. That makes SB26ADC stupid cheap, and the best buy I have ever done. Won't need another tweeter ever again.
I play loud sometimes, that's why I've been waiting for the SB waveguides for the SB26ADC for a long time now. However, I've never ran them into distorting anything close to what SB29 or TW29 do (they get nasty when played loud). I am seriously rethinking the idea of even needing waveguides for the tweeters at all (even dispersion characteristics are close enough to what I wanted).
Sorry for the long post, hope you will find it useful.
Thanks Robbin,
I was suspicious of this too. And good news is, the ceramic version (which really looks like a deep oxidized aluminium) is already available through two shops in Europe - its resonance is almost unnoticable and is higher - looks like 34Khz. Looks like identical otherwise so will be ordering a pair today
I was suspicious of this too. And good news is, the ceramic version (which really looks like a deep oxidized aluminium) is already available through two shops in Europe - its resonance is almost unnoticable and is higher - looks like 34Khz. Looks like identical otherwise so will be ordering a pair today
Do what you Will. I was interested but the information you have posted is only a statement.all, too long posting here
That was interesting. I've never heard a ring-radiator, but most people now think it is a better idea than a soft dome. Controls the central breakup better.
But maybe the best game in town is still metal domes.
Nobody here reads these sort of links, but I was greatly influenced by Robin Marshall's interview at Stereophile on tweeters. I don't think ring radiators were around then. At the time, he actually liked cone tweeters, but designed around mylar and metal, usually from SEAS.
Robin Marshall: A Modicum of Genius | Stereophile.com
Interestingly he thought ceramic domes might be even better than metal, but the technology was lacking then.
Does anyone have any observations on using Zobels to control the very top end, or whether 2nd and 4th order tweeter filters work better than third order because they control the Fs resonance better?
Anyhoo, metal is clearly still a contender. Harbeth use it, and they aren't in the boom and tizz category.
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Problem with soft domes is at higher frequencies the dome would go in all directions. This isn`t a problem for hard domes hence the use of aluminium and magnesium. However, they have a breakup node which induces sharp spikes in harmonic distortion in the audible range and can be excited even if outside the audible range (by harmonics). So, none are indeed better - both have issues. It also depends on how the dome is driven - if the coil is smaller than its diameter or if its driven by the dome boundary.
What is interesting is how the oxidizing of the ADC pushed the resonance higher and decreased its magnitude as the mms remains the same. Al2O3 should have some internal damping or I miss something.
What is interesting is how the oxidizing of the ADC pushed the resonance higher and decreased its magnitude as the mms remains the same. Al2O3 should have some internal damping or I miss something.
Most domes are driven at their surround contact. The soft dome center would move opposite or not in the same direction as the outer ring where it is driven at higher frequencies. This creates variations in the radiating area and cancellations when the center of the dome moves opposite to the boundary. Not a problem for rigid pistons but they introduce another as described in my previous post. Ring radiators avoid this problem but they distort more in the lower spectrum and have to be used higher or ideally, in waveguides/horns. Besides this, I have yet to hear a ring radiator that has high frequency output (they do on measurements and paper but just sound like they don`t have it, the so called dark sound). When you compare their 10Khz+ performance to a live event or a good dome, they (rr) just don`t do well there and need extra support. from a supertweeter in my opinion.
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In both tweeters break-up is visible in the same place on the impedance.
SB26ADC-C000-4 :: SB Acoustics
SB Acoustics :: SB26CDC-C000-4
Attachments
not a problem also for anular domes that are better then rigid domes because because don't have a "dome"
however metal domes has a lot of ringing/resonant boundary in waterfall analysis
p.s.
thare are domes beter then rigid and viceversa
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