Here's some interesting info about Alnico magnets and when they need to be recharged.
I agree with myhrrhleine about the sonics of the surround & spider assemblies. This is an aspect of driver design, particularly pro equipment, that isn't always clearly described, except for extreme high-power, long-excursion considerations.
I agree with myhrrhleine about the sonics of the surround & spider assemblies. This is an aspect of driver design, particularly pro equipment, that isn't always clearly described, except for extreme high-power, long-excursion considerations.
Hello Lynn
May I ask what is your opinion of the beryllium diaphragm version of this particular Radian driver? It has not been out for long, and before puling the trigger on a pair, I would like to hear from someone who has listened to them.
B.t.w. I think this is a great thread, and already have the AH425 Azurahorn.
Pierre
I bet this new Radian 745NEO comes with other changes than just BePB makingit difficult to see what the Be has done. Clearly, while technically better the perfrormance may be beyond the quality of the other parts and even then not really enough to justify the cost. A new BMW will cost typically £30K to £40K. A state of the art Super HiFi speaker will cost the same, but the BMW has far more parts with very highly evolved engineering. It cannot be made by a DIY er period. The best HiFi speakers used at low and normal listening levels can be made for a few hundred pounds. I have been making and designing sound systems for decades. A few cheap SEAS dirvers will do everything I want.
I would like to make new speakers as a hobby but I cannot really better what I have made. I have some old Quad ELS57. Great speaker but lack of dynamics. Still not bettered at 85dB in many ways. Direct drivers remain the best way to a good overall sound. The Radian 745NEOBePB does not get a look in. Nor does the RAAL ribbon.
I do not know of anybody that makes their own hifi period. Excellent small complete systems can be bought at the local store. Excellent sound systems come with cars like BMW etc.
We need to keep DIY alive.
I would like to make new speakers as a hobby but I cannot really better what I have made. I have some old Quad ELS57. Great speaker but lack of dynamics. Still not bettered at 85dB in many ways. Direct drivers remain the best way to a good overall sound. The Radian 745NEOBePB does not get a look in. Nor does the RAAL ribbon.
I do not know of anybody that makes their own hifi period. Excellent small complete systems can be bought at the local store. Excellent sound systems come with cars like BMW etc.
We need to keep DIY alive.
For clarity, my question is not about whether the Be is good value or not. This is a personal assessment and what is good value to one may not be to someone else. We all end up facing diminishing returns as we attempt to design hifi systems that push the enveloped in one way or another.
To go back to the question, what I expect from the new 3 inch Be diaphragm is lower distortion, and resonances that occur at higher frequencies. The regular mylar-aluminum Radian diaphragm is already pretty darn good it seems. So I wonder how the new Be one sounds in the midrange, and the high frequencies. In practice, does it lessen the need for a tweeter? Does it provide more clarity in the midrange and is it noticeable? And since the suspension must be different, how is the tonality of this midrange at the lower end, compared to the mylar-aluminum version?
I did not intend with my previous post to put Mr Olson on the spot. This new 3 inch Be diaphragm driver offers an alternative to DIYers that we did not have before. As far as I know there is nothing else quite like it. Hence the curiosity. So if anyone who has tried this driver would be willing to share their experience, I think there are a few of us who are impatient to read more (anything) about it
.
Cheers - Pierre
To go back to the question, what I expect from the new 3 inch Be diaphragm is lower distortion, and resonances that occur at higher frequencies. The regular mylar-aluminum Radian diaphragm is already pretty darn good it seems. So I wonder how the new Be one sounds in the midrange, and the high frequencies. In practice, does it lessen the need for a tweeter? Does it provide more clarity in the midrange and is it noticeable? And since the suspension must be different, how is the tonality of this midrange at the lower end, compared to the mylar-aluminum version?
I did not intend with my previous post to put Mr Olson on the spot. This new 3 inch Be diaphragm driver offers an alternative to DIYers that we did not have before. As far as I know there is nothing else quite like it. Hence the curiosity. So if anyone who has tried this driver would be willing to share their experience, I think there are a few of us who are impatient to read more (anything) about it
.Cheers - Pierre
All Radian compression drivers are now available from US Speaker with Be diaphragms. The diaphragms are the only difference between the standard and Be models. Materion published an interesting tech brief comparing the standard and Be diaphragms in a 950PB-16 driver.
For me, the difference in the waterfall plots says it all.
For me, the difference in the waterfall plots says it all.
The AH425 Azurahorn and the new Radian 745NEOBePB cannot represent a successor to the Ariel because it represents a totally dfferent sector of HiFi.
Having said that, of course there is no problem letting the threads stream through a different sector. The shear power and price of the above horn set up is far away from Ariel. That is why I raised the considerably high cost of the Radian Azura horn set up suited to a hall or very large room.
Even my 2 x 20 triode amp would be running at the bottom of the class A range with 115dB sensitivity.
Having said that, of course there is no problem letting the threads stream through a different sector. The shear power and price of the above horn set up is far away from Ariel. That is why I raised the considerably high cost of the Radian Azura horn set up suited to a hall or very large room.
Even my 2 x 20 triode amp would be running at the bottom of the class A range with 115dB sensitivity.
The waterfall plot is very revealing especially when taking the impulse test into account. Very good result for a large driver suitable for professional and large domestic systems.
I would look at 1" throated variants. These will be the ones to check out as the domes may well be stiffer with even better waterfall.
I would look at 1" throated variants. These will be the ones to check out as the domes may well be stiffer with even better waterfall.
It's obvious to the eye - but to the ear? Up that high? I'm curious.
Indeed.... CSD plots don't tell much about what we hear, especially when it comes to compression drivers and horns. The FR plots tell the story of what the ear will hear. With no difference up until 10 kHz, it is doubtful what the Be diaphragm is adding. Also, if you look at the smoothed plot, the Be diaphragm has the same chaotic behavior, even though the CSD appears to be clean. Much ado about nothing?
You use a 1.4" throat, right? I think the most promising driver for 1.4" is the Beyma CP755Nd/Al. Check out the measurements:
http://profesional.beyma.com/ingles/pdf/CP755NdAL.pdf
But again, its pretty expensive (about $700 each, last I checked).
http://profesional.beyma.com/ingles/pdf/CP755NdAL.pdf
But again, its pretty expensive (about $700 each, last I checked).
in 350 hz tractrix horn three Be drivers tested over a year or so listening the TAD 2001, 4001, 4002 drivers I liked the 4002 neo motor 1.5 exit (2" extension removed) best then the 1" 2001 alnico then the 2" alnico 4001. In a much bigger longer horn the 4001 ruled. Be to me always sounds hyped and fake in a fantastic way and alnico motors really don't sound better until you are subjected to the hype
Not to step on any toes, but the new speaker is a successor to the Ariel because I say it is. I've lived with my Ariels for 20 years, was there at the creation, and know it better than anyone. A long time ago, I hoped the European driver industry would gradually make drivers flatter, with better impulse response, and more efficient, if only by a few dB.
It didn't happen. Compared to the 5.5" Vifa, the responses of newer drivers got rougher, the impulse response worse, and efficiency did not go up ... in some cases, it went down. The only vendor that kept the same line of development as the original Vifa and Scan-Speak drivers was Skaaning. I was tempted to develop a Mark II Ariel based on the Skaaning drivers, but after avoiding horns for so long, it was time to learn something about them. Bjorn Kolbrek and Martin Seddon were my mentors, and the AH425 resulted from that collaboration.
I've heard the first prototypes based on the AH425, the GPA 288 and Radian 745Neo (Aluminum) drivers, and the GPA 416-Alnico. Despite the dissimilar technology, the prototypes sound surprisingly close to Ariels ... like a very big Ariel with another 10 dB of headroom. Depth is somewhat greater, width is about the same, and resolution is much higher. They are even less suited for 200W Class AB transistor amps than the Ariels.
The Ariels were designed to mimic the sound of stacked Quad ESL57's. They measure similarly, and I've had many Quad owners over the years tell me the Ariels sound remarkably close to ESL57's ... but with 5 to 10 dB more headroom and better imaging.
It might seem a little weird to imagine a loudspeaker that has sonic aspects of stacked Quad ESL57's, the Ariels, and a very smooth Altec, but that's what the new speaker sounds like.
The prototypes do not sound like Avante-Gardes, Acapellas, Cessaro, the JBL DD66000 Everest, or Volti speakers. The bass region has similarities to the Oswald's Mill speakers, since the bass drivers are similar (and might be the same). If the AE drivers I heard at the RMAF were representative (they were used in about 5 or 6 systems being exhibited), the GPA Alnico's sound pretty different, in a way that's hard to describe.
As for aluminum versus beryllium diaphragms, I'll choose the material that has the fastest decay time, provided that the subjective aspects are acceptable. The AH425 has very low coloration, so what you hear the sound is the sound of the diaphragm (and phase plug). Unless there is something very wrong with Materion's version of beryllium, that'll be my choice.
The Materion beryllium is rolled from metal sheets that are compressed on rollers, instead of being vapor-deposited like the TAD diaphragms. As a result, the crystal structure is very different, and the Materion beryllium is not brittle; in fact, you can punch through the sheet with a ballpoint pen, and it doesn't fracture.
At the RMAF, I picked up 3" diaphragms intended for the 745Neo, and the Beryllium seemed to be half the weight of aluminum. It's a very light metal, much lighter than aluminum, and has better self-damping. The Be tuning forks are much quieter than the aluminum or titanium tuning forks, and damps much more quickly. It really does behave differently, so I expect different sonics as well. Hard to imagine that lighter weight, improved self-damping, and freedom from metal fatigue would be sonic demerits, but the proof is in the listening.
Berylliosis isn't fun
I'm sure that Lynn knows but for anyone who doesn't, beryllium has some potentially serious health impacts if inhaled - just like our lead solder one needs to know what not to do. Or our cadmium passivation.
Otherwise it's got some wonderful properties. Can I say "yes" yet?
I'm sure that Lynn knows but for anyone who doesn't, beryllium has some potentially serious health impacts if inhaled - just like our lead solder one needs to know what not to do. Or our cadmium passivation.
Otherwise it's got some wonderful properties. Can I say "yes" yet?
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I already posted this, but here is a comparison between the Be and JBL ribbed Ti :
That is a net 3dB sensitivity gain in midband, and a very smooth extension in the top end, without using spurious resonances from the surrounds.
3rd distortion is also a lot lower, but I cannot guaranty it does not come from the driver itself (the frequency response *is*identical between the two drivers when the same diaphragm is used though).
Now to the ear, the gain is notable even in the <10kHz range (made the test with a low pass).
That is a net 3dB sensitivity gain in midband, and a very smooth extension in the top end, without using spurious resonances from the surrounds.
3rd distortion is also a lot lower, but I cannot guaranty it does not come from the driver itself (the frequency response *is*identical between the two drivers when the same diaphragm is used though).
Now to the ear, the gain is notable even in the <10kHz range (made the test with a low pass).
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