Not sure about the exact size either but I've read something like 8 or 9 inches.
The S version ATC uses in all but one of their speakers has something like 8kg (17.5lb) of ferrite magnet.
Who talked about ignoring waveguide equiped tweeters ? I just reported the ATC drivers size in my post
I actually have a positive opinion on the use of waveguides :
- The standard tweeter flange size is 104mm. Instead of the useless flange you use a waveguide of the same size, or better an elliptical one in order to match the midrange driver horizontal directivity without increasing CTC distance.
- As you are probably aware, since most waveguides offer a sensitivity boost in the lower range of the tweeter, lower crossover points can be used, which compensate for the larger CTC distance.
- I don't consider ATC design to be optimal. For a similar driver arrangement, Neumann KH420 rotative midrange/tweeter large waveguide is better IMO. To me if there is unused space on a flat speaker baffle, it may as well be used as a waveguide.
- Being a recording/mixing technician, I personnaly don't care too much about narrow vertical directivity. Quite the contrary, it reduces desk reflections, and my head height is always the same anyway.
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This guy may know before he boxes them up for sale/delivery.
Pioneer TAD TL-1601A and ATC SM75-150S super
The Volt VM752 is very similar to the ATC SM-75-150. The Volt requires a 6 inch cutout hole on the baffle and is rear-mounted. The magnet is 8 inch diameter.
There are many competing attributes of a speaker design which must be compromised to create a complete system... Some attributes are more important than others. Vertical CTC distance is one of those attributes which tends to get compromised in favor of other more important attributes.
There are many competing attributes of a speaker design which must be compromised to create a complete system... Some attributes are more important than others. Vertical CTC distance is one of those attributes which tends to get compromised in favor of other more important attributes.
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900 euro plus -One of the reasons Yamaha never went with Be domes again was the total cost involved in manufacture and safety procedures.Any less than that and I would be very surprised
Yamaha could easily sell 10000 new Be domes for the old NS 1000 speakers - so the numbers must not be good. If these Biesma could be modded to work in these Yamaha they will sell boat loads
Saying that I want something like this - might mod my Kappa9 and go Berylium active
We should have a better understanding of the cost by mid summer. I sort of had settled for the Accuton C90-6-724 as my midrange and since me purchasing any drivers will happen late summer/early fall, Its going to be interesting to see where the 3" Be lands, performance and price considered.
Hi,
The question was more focused of the ctc with waveguide. I do not know if the ctc rule apply the same with WG not because their low end but their wild dispersion.
I often see WG tweeter with high cut offs 2k hz and a little more sometimes... if the ctc rule applies, I was aking myself whether they can be used or not.:confused.
Or as you say it s a simple trade off, some gave up vertical dirsctivity or accept nulls for a co trolled directivity ?
The question was more focused of the ctc with waveguide. I do not know if the ctc rule apply the same with WG not because their low end but their wild dispersion.
I often see WG tweeter with high cut offs 2k hz and a little more sometimes... if the ctc rule applies, I was aking myself whether they can be used or not.:confused.
Or as you say it s a simple trade off, some gave up vertical dirsctivity or accept nulls for a co trolled directivity ?
I am clearly not the expert here, but... The CTC should be treated as its own thing on top of voice coil alignment and waveguide size, things then become relatively clear.
1. CTC (vertical) should be the least amount of compromise such that there is an even on/off axis behavior and minimum phase issues or nulls in the responses.
2. CTC (horizontal front to back) is to align the acoustic center of each driver.
3. Waveguide opening should be close to the same size as the end of the mating drivers diaphragm. Conical or exponential wave propagation is to ones liking.
"All horns are waveguides but not all waveguides are horns"
1. CTC (vertical) should be the least amount of compromise such that there is an even on/off axis behavior and minimum phase issues or nulls in the responses.
2. CTC (horizontal front to back) is to align the acoustic center of each driver.
3. Waveguide opening should be close to the same size as the end of the mating drivers diaphragm. Conical or exponential wave propagation is to ones liking.
"All horns are waveguides but not all waveguides are horns"
Yes, for all intents and purposes the use of a waveguide doesn't change the general effects of CTC. The use of a waveguide on a regular dome tweeter usually allows you to cross lower as the tweeter doesn't have to work as hard to produce the same sound level, therefore you can afford to push the crossover frequency down a bit to compensate for the increased CTC.
The review of the 8-Ohm version PTT6.5W08-01B (new name is PTT6.5X08-NFA-01) of the popular long-stroke midwoofer PURIFI PTT6.5W04-01A
Purifi PTT6.5W08-01B (PTT6.5X08-NFA-01) | HiFiCompass
Purifi PTT6.5W08-01B (PTT6.5X08-NFA-01) | HiFiCompass
I rolled my own, and can verify with some crude measurements the ridiculously low distortion from this driver. But speaker design is 90% about crossover design, and Rick of Selah Audio knows his stuff here…
If the target is a speaker than can hit 100dB from 20Hz to 20Khz a 1/2 cut speaker, 15-at distortion levels previously unheard of, this will do it…
Selah Audio Purezza Bookshelf Speaker Review
If the target is a speaker than can hit 100dB from 20Hz to 20Khz a 1/2 cut speaker, 15-at distortion levels previously unheard of, this will do it…
Selah Audio Purezza Bookshelf Speaker Review
The measurements of the tiny "Revelator" ScanSpeak D2104/712000 tweeter:
ScanSpeak D2104/712000 "Revelator" | HiFiCompass
ScanSpeak D2104/712000 "Revelator" | HiFiCompass
HifiCompass, thank you for that one. I was surprised ith your 3/5 stars rating, but after seeing the measurements I understood. I wonder what is wrong with that driver as distortion measurement is not what I am used to from Scan Speak tweeters. For now it seems better to stay away from this one, especially for that money, and better to take D2004. Not only its distortion measurement is excellent, but it has very small flange and I value that a lot.
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I think, the tweeters that cost $385/pair have no rights to have such rugged frequency response and distortion profile. I'm disappointed, because waited they would continue nice performance of great SS tweeters D2904, D3004, D2004. If it had a ceramic, beryllium or dimond dome, it could be forgiven. But it has a regular soft dome and there are too many competitors at that price level.
The second tweeter from a matched pair had even worse distortion. I always publish results for a better sample.
The second tweeter from a matched pair had even worse distortion. I always publish results for a better sample.
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