Perhaps it depends on the relevance of the data. For example, the TB 3" referred to earlier is barely imported into Europe despite good THD measurements, good SPL if the spec is to be believed, good package size by ATC standards and good price compared to the ATC and the OPs proposed price. What is the cause of this lack of enthusiasm? What should be measured in order to see it?
As a brand TB are barely imported into Europe anyway. Yes, there are places you can get their drivers, but the range held is usually quite lack lustre compared to the huge range of drivers that the company make.
Most people aren't even interested in mid range drive units, let alone dome mids that tend to be harder to work with.
Regardless of whether or not you believe in its relevance the data is always important. Both linear and non linear distortion represent the devices unaided capability in being able to faithfully output what has been input. Maybe people don't believe in THD measurements, or are less concerned with absolute flatness of response. But if there were two similar drivers available at equal price points even the nay-sayer would opt to buy the driver with better objective performance.
Yes a tough crowd, but when one starts a thread titled
You're going to get a tough crowd as the ATC is almost legendary and for good reason. It will be interesting to see how this driver stacks up when the measurements start appearing.
Most people aren't even interested in mid range drive units, let alone dome mids that tend to be harder to work with.
Regardless of whether or not you believe in its relevance the data is always important. Both linear and non linear distortion represent the devices unaided capability in being able to faithfully output what has been input. Maybe people don't believe in THD measurements, or are less concerned with absolute flatness of response. But if there were two similar drivers available at equal price points even the nay-sayer would opt to buy the driver with better objective performance.
Yes a tough crowd, but when one starts a thread titled
You're going to get a tough crowd as the ATC is almost legendary and for good reason. It will be interesting to see how this driver stacks up when the measurements start appearing.
My 2 cents, this midrange dome should be: A. better, B. cheaper. C. different. D solve a problem the competing midrange domes have. To be succesfull. How about a dimple dome? These new wide suspension tweeters by SB, Wavecor, etc seem to be very good at lowering distortion and extend range.
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The dimple domes or ring radiator varients do not lower distortion over what traditional domes can manage.
Are the measurements of the ATC. Its frequency response is very easy to work with. The narrow dip between 3-4kHz isn't perfect so is one area that could be improved upon, but it is likely inaudible. The distortion performance is flawless, it is relatively sensitive and has enough xmax to back up a lower rather than higher xover if needed.
The only area where it falls down is price and the size of the flange, meaning you cannot get close C-C spacing. A neo motor could probably solve some of the size issue, but would be somewhat expensive, price is ridiculous even for what you get however. They clearly charge what they can.
The TB solves the price issue and improves upon the size problem. Its FR isn't quite as smooth, but is equally workable and its THD is also extremely low. It probably cannot be used down quite as low as the ATC if you were really interested in pushing it, but it'd easily support 500Hz-3kHz.
A close to ideal dome mid range would have the upper end distortion of the TB, the lower end distortion of the ATC, a reasonable amount of xmax, around 90dB sensitivity RE 8 ohms, a small neo motor with flange to get it as close to the tweeter as possible and a smooth frequency response without any dips or peaks within, or around, its passband (say 350Hz- 4kHz) that would be indicative of internal reflections.
If you can pull that off for <$100 a piece you'll be onto a winner. Even still, there wont be a tremendous amount of demand for such a driver, although it'd be nice to have.
Are the measurements of the ATC. Its frequency response is very easy to work with. The narrow dip between 3-4kHz isn't perfect so is one area that could be improved upon, but it is likely inaudible. The distortion performance is flawless, it is relatively sensitive and has enough xmax to back up a lower rather than higher xover if needed.
The only area where it falls down is price and the size of the flange, meaning you cannot get close C-C spacing. A neo motor could probably solve some of the size issue, but would be somewhat expensive, price is ridiculous even for what you get however. They clearly charge what they can.
The TB solves the price issue and improves upon the size problem. Its FR isn't quite as smooth, but is equally workable and its THD is also extremely low. It probably cannot be used down quite as low as the ATC if you were really interested in pushing it, but it'd easily support 500Hz-3kHz.
A close to ideal dome mid range would have the upper end distortion of the TB, the lower end distortion of the ATC, a reasonable amount of xmax, around 90dB sensitivity RE 8 ohms, a small neo motor with flange to get it as close to the tweeter as possible and a smooth frequency response without any dips or peaks within, or around, its passband (say 350Hz- 4kHz) that would be indicative of internal reflections.
If you can pull that off for <$100 a piece you'll be onto a winner. Even still, there wont be a tremendous amount of demand for such a driver, although it'd be nice to have.
I don't know about that given that Volt, the only realistic competition to the ATC dome at the moment, costs a fair bit more ATC might actually be charging what they have to.
@ 5th element. I think this is pretty amazing extension for 9.6 cm2 dome tweeter. That's what i ment with respect to bandwidth.
I cannot see why
Needs to cost £340
There's more magnet in a 10" XLS that you can get for £80 on ebay and again the XLS also has more metal work in it elsewhere vs the ATC. There is profit in it for the guy on ebay too.
Sure the XLS isn't crammed full of copper or similar or whatever, but there's no way you can convince me that an equivalent driver needs to cost that much.
I mean look at some of the AE TD series, some of those cost less than the ATC and pack far more 'stuff' into the driver.
I suppose it's a bit like the SB acoustics standard range of drivers. Cast frames, lots of copper in the motor, well ventilated, excelllent performance and an attractive cost.
As I said: I don't know.
I just would have thought that there must be a reason why the Volt dome costs £170 more than a 18" Volt Radial for example. Somehow I suspect labour cost to be a large part of the equation since, unlike SB and Peerless, Volt and ATC are made in Europe/UK.
I just would have thought that there must be a reason why the Volt dome costs £170 more than a 18" Volt Radial for example. Somehow I suspect labour cost to be a large part of the equation since, unlike SB and Peerless, Volt and ATC are made in Europe/UK.
dont forget to use a large rear chamber ....🙂
Pretty hard to believe, the distortion must be off the chart ......😱
You're talking about extending the range with respect to the upper end. I thought you were meaning the lower end, as this is where it's a challenge to keep the distortion low. Yes the ring domes do manage better upper end, on axis extension, but they have poorer off axis.
I like the dome center indent, I had experimented with this 2 decades ago , extends the top end, with excellent clarity ....
And it should prevent rocking of the voice coil on a larger dome if i understand the mechanics of these dimple domes correct.
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My opinion is that the rhythmsandy's chance of success with their driver-in-development will be basically zero, based on that nonsense. If I understood correctly what rhythmsandy was trying to say, then it seems as though he thinks a piano recording, played over a zero-distortion speaker, would end up sounding like 88 different tuning forks.
rhythmsandy, very interesting project, thank you for sharing the design process here!
You talk about microdynamics and suspension design. What mechanical resistance (T/S Rms) are you aiming for?
As for the frequency range, the ATC aims for the 350Hz-3.5kHz decade, whereas the TB is more like 500Hz-5kHz (being optimistic here).
I think an interesting frequency range to target would be the 200Hz-2kHz decade (or 250-2.5), as it would cover the lower fundamentals of human voices.
The large external diameter of your unit (because of the large suspension) will go against a high LP crossover frequency anyway, because of the c-c distance with the tweeter.
Nowadays tweeter tend to have a lower Fs, making 2kHz a workable solution, especially with steep active slopes. Waveguides can also help there...
So please, make it a low midrange driver, with a very low mechanical resistance.
Oh and a high enough xmax, and enough VC material to avoid too much "instantaneous" power compression given the lowish sensitivity. Those last two probably go against the underhung design tho...
End of the wishlist 😀
You talk about microdynamics and suspension design. What mechanical resistance (T/S Rms) are you aiming for?
As for the frequency range, the ATC aims for the 350Hz-3.5kHz decade, whereas the TB is more like 500Hz-5kHz (being optimistic here).
I think an interesting frequency range to target would be the 200Hz-2kHz decade (or 250-2.5), as it would cover the lower fundamentals of human voices.
The large external diameter of your unit (because of the large suspension) will go against a high LP crossover frequency anyway, because of the c-c distance with the tweeter.
Nowadays tweeter tend to have a lower Fs, making 2kHz a workable solution, especially with steep active slopes. Waveguides can also help there...
So please, make it a low midrange driver, with a very low mechanical resistance.
Oh and a high enough xmax, and enough VC material to avoid too much "instantaneous" power compression given the lowish sensitivity. Those last two probably go against the underhung design tho...
End of the wishlist 😀
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Not sure if I would trust a 3" dome to do justice to 200Hz. I get the feeling that ATC is pretty much at the limit of what can reasonably done with a dome that size.
If I wanted a mid to cover 200-2000Hz I'd be happier (until proven otherwise) with a 5" cone.
If I wanted a mid to cover 200-2000Hz I'd be happier (until proven otherwise) with a 5" cone.