Hi ScottG,
my posted/uploaded Radian 1" 3-slit Bob Smith phase plug measurement was made with gated steady state sine on a LinearX LMS analyser. So no impulse response there I'm afraid. When I hopefully get my HP35665A back up and running (please - I pray), I will of course with great delight make new measures incl. waterfall and other FFT based ones.
This driver is truly remarkable - it even impressed Radians owner when he was here in connection with the London Plasa show and had a listen to it...
Kind regards
a1greatdane
my posted/uploaded Radian 1" 3-slit Bob Smith phase plug measurement was made with gated steady state sine on a LinearX LMS analyser. So no impulse response there I'm afraid. When I hopefully get my HP35665A back up and running (please - I pray), I will of course with great delight make new measures incl. waterfall and other FFT based ones.
This driver is truly remarkable - it even impressed Radians owner when he was here in connection with the London Plasa show and had a listen to it...
Kind regards
a1greatdane
If you wanna give my min phase contour a try, I'd definitely like to support your giant project with a calculation for the driver you use...
http://www.diyaudio.com/forums/multi-way/103872-geddes-waveguides-67.html#post1930266
Michael
Member
Joined 2003
I already have another flare (actually two) I want to try as soon as I recover from this project.
Sure can't hurt to take a look at a third. The drivers are the Eighteen Sound ND1460As. 1.4" exit with a 10 degree overall exit angle (5 degrees per side). Can't tell you anything about the internal dimensions of the drivers because I didn't take them apart.
Paul
Sure can't hurt to take a look at a third. The drivers are the Eighteen Sound ND1460As. 1.4" exit with a 10 degree overall exit angle (5 degrees per side). Can't tell you anything about the internal dimensions of the drivers because I didn't take them apart.
Paul
Member
Joined 2003
Hi Paul W,
many tnx. and no need - I'm happy to supply...
The easiest option is to modify a Radian standard product. You just have to send me the phase plug bit, I do the modification work, U pay me something for the effort and I ship it back 2 U (and then hopefully 'Bob could B Ur uncle'? English appraisal phrase I believe...).
Just let me know...
Cheers
Sven R. Olsen
Creator
CSW-Chilli Sound Works
Manor House
London N4
UK-England
many tnx. and no need - I'm happy to supply...
The easiest option is to modify a Radian standard product. You just have to send me the phase plug bit, I do the modification work, U pay me something for the effort and I ship it back 2 U (and then hopefully 'Bob could B Ur uncle'? English appraisal phrase I believe...).
Just let me know...
Cheers
Sven R. Olsen
Creator
CSW-Chilli Sound Works
Manor House
London N4
UK-England
That's what I like to hear!
How about in relation to the other driver's you have used (..and yeah, I know - not exactly an "apples to apples" comparison.) For instance I once posited that the subjective sense of *depth* should be improved with this driver.. has this been your experience when compared to other compression drivers?
Member
Joined 2003
Scott,
Those are tough questions since the systems are all so different it makes direct comparison somewhat futile.
The other compression driver I am most familiar with is the BMS 4552ND which sounded "crunchy" in comparison to the 1460A...but in fairness to the BMS, it is a much smaller driver, I was trying to push it lower in frequency than it was comfortable, WGs were only 1/3 the size, mounted on relatively small baffles instead of full IB, less than half the cost, etc, etc. Truly an apples-hamburger comparison.
Soundstage depth is something I associate more with system implementation than individual drivers. We've got good depth, but is it because of the 1460...dunno.
Happy with the 1460s though...can't think of another driver I'd rather have in this system.
Paul
Those are tough questions since the systems are all so different it makes direct comparison somewhat futile.
The other compression driver I am most familiar with is the BMS 4552ND which sounded "crunchy" in comparison to the 1460A...but in fairness to the BMS, it is a much smaller driver, I was trying to push it lower in frequency than it was comfortable, WGs were only 1/3 the size, mounted on relatively small baffles instead of full IB, less than half the cost, etc, etc. Truly an apples-hamburger comparison.
Soundstage depth is something I associate more with system implementation than individual drivers. We've got good depth, but is it because of the 1460...dunno.
Happy with the 1460s though...can't think of another driver I'd rather have in this system.
Paul
Dear Paul W,
glad to hear Ur happy with the 18sound driver (it's allway nice to find something U can acept and live with - oder?).
I take it's the version with aluminium diaphragm?
Have You by any chance tried the Radian 835? (not that I shall pretend to be their rep in any sense..), I have just used it in some 'stuff' after having tried and tested most other to me available drivers, but this was for Sound Reinforcement purposes mind U... And it was also b4 the 1460A.
Which I in all fairness can't recall having had the pleasure to concious listening 2 - mayb again in something from Noise Control, but quite sure that was nice titanium crunching away diaphragms - not sure...
a1gd
glad to hear Ur happy with the 18sound driver (it's allway nice to find something U can acept and live with - oder?).
I take it's the version with aluminium diaphragm?
Have You by any chance tried the Radian 835? (not that I shall pretend to be their rep in any sense..), I have just used it in some 'stuff' after having tried and tested most other to me available drivers, but this was for Sound Reinforcement purposes mind U... And it was also b4 the 1460A.
Which I in all fairness can't recall having had the pleasure to concious listening 2 - mayb again in something from Noise Control, but quite sure that was nice titanium crunching away diaphragms - not sure...
a1gd
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Member
Joined 2003
Yes, the 1460A is the one with the aluminum diaphragm.
I haven't had the opportunity to hear the Radian. One of the things that caused me to pick the 1460A is the copper in the motor which I don't think the Radian has. The copper enables a very flat impedance curve for good HF extension and low distortion. Notice how flat the HF impedance is in this graph.
(This graph is a little hard to read since I forgot to change pen colors for the two plots, but this is the 1460A with and without the WG. Without the WG, the impedance peaks just above 500 and 2k. With the WG, the peaks are lower Q and lower in frequency.)
I haven't had the opportunity to hear the Radian. One of the things that caused me to pick the 1460A is the copper in the motor which I don't think the Radian has. The copper enables a very flat impedance curve for good HF extension and low distortion. Notice how flat the HF impedance is in this graph.
(This graph is a little hard to read since I forgot to change pen colors for the two plots, but this is the 1460A with and without the WG. Without the WG, the impedance peaks just above 500 and 2k. With the WG, the peaks are lower Q and lower in frequency.)
Hi Paul W,
I have in the meantime been on the 18sound website an found just that. The impedance curve here looks remarkable as well. The Radian 835 does employ some copper in the gap, but I don't think impedance response as good as your uploaded one.
Commonalities for both is aluminium dome diaphragm and voice coil size close to 3".
According to R. Smith the chosen size should only provide even frequency response incorporating a 3 slit design to about 16kHz. If You want that to extend beyond 20kHz, then the diaphragm size has to decrease to below 2.5" or You have to employ 4 slits (the devil or the deep blue sea, anyone?).
Therefore possibly an attempt with a 2.4" one in the form of the ND1424? But here the diaphragm is made in titanium and the phase plug implementation might not be conceptually the same...
Cheers
a1greatdane
I have in the meantime been on the 18sound website an found just that. The impedance curve here looks remarkable as well. The Radian 835 does employ some copper in the gap, but I don't think impedance response as good as your uploaded one.
Commonalities for both is aluminium dome diaphragm and voice coil size close to 3".
According to R. Smith the chosen size should only provide even frequency response incorporating a 3 slit design to about 16kHz. If You want that to extend beyond 20kHz, then the diaphragm size has to decrease to below 2.5" or You have to employ 4 slits (the devil or the deep blue sea, anyone?).
Therefore possibly an attempt with a 2.4" one in the form of the ND1424? But here the diaphragm is made in titanium and the phase plug implementation might not be conceptually the same...
Cheers
a1greatdane
You find the software under
AxiDriver
Its free to use - if you do not need to save your projects (which becomes tiring pretty quick) - or you pay a more than moderate fee for non-commercial use.
When I "discovered" this software by coincidence R&D Team just dropped price for us DIYers considerably
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-119.html#post1876853
Michael
AxiDriver software
Hi Michael,
many thanks for link.
I have already got AkaBak from those chaps (that will be Joerg Panzer, who I happen 2 know, & Co...), so that certainly further confidence builds about the quality of the program.
Joerg is a very clever chap with his element manoeuvres.
Best regards
Sven aka a1greatdane
Hi Michael,
many thanks for link.
I have already got AkaBak from those chaps (that will be Joerg Panzer, who I happen 2 know, & Co...), so that certainly further confidence builds about the quality of the program.
Joerg is a very clever chap with his element manoeuvres.
Best regards
Sven aka a1greatdane
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Member
Joined 2003
Hi Sven,
(Do you prefer GD or Sven?)
I wasn't aware Radian used copper in their motors...didn't see it when I looked at Radian driver info. That is good news. Extension from 16k-20k is good, but does not help me since my ears cannot hear above 14k. On the other hand, if I can get it, why not?
Here is the speaker with ribbon CSD measurement you were asking about in Earl's thread. Unfortunately, Geocities hosting site has closed, so website for this speaker is down...but I will recreate it at some point.
Paul
(Do you prefer GD or Sven?)
I wasn't aware Radian used copper in their motors...didn't see it when I looked at Radian driver info. That is good news. Extension from 16k-20k is good, but does not help me since my ears cannot hear above 14k. On the other hand, if I can get it, why not?
Here is the speaker with ribbon CSD measurement you were asking about in Earl's thread. Unfortunately, Geocities hosting site has closed, so website for this speaker is down...but I will recreate it at some point.
Paul
Hi Paul,
good to hear from U and no worries U can address me almost any way U like (U know - dear child - many names...).
I have seen that very nice looking box previously when reading through the thread(s). There's definately a very competent joiner at large there somewhere... Good to hear there might be a curve potentially coming at some point. There is definitely something going for Large ribbons and small for that matter, but in my main field of Sound Reinforcement work, they do tend to fall in the inadequate bracket, if nothing else, then maybe be course they might actually be to clean for that purpose and therefore present a cultural difference the sound engineers, only with great difficulty can get used to.
A bit more of a 'hands on' explanation, I suppose, as supposed to the more theoretical based one given by Dr. Geddes.
I mean U have as well for this rather large latest system of your creation, chosen to use a compression driver for probably some of the same reasons?
I myself (said the dog) use a couple of very special 1"s incorporating some Radian parts, in my rather large lounge system, be course I could and since I could not within the given economics employ capable enough ribbons or magneto static devices. So I suppose We R a bit in the same boat?
Re. Radian and copper: To my knowledge they only employ copper on their most expensive offerings like the 1" 475. I shall not say for definite, if it's even in the 835. What I do know about that driver, I think all ready posted. I also know it's not in the model down from there; 635? They got their nomenclature a bit mixed, if You really ask Yours truely. I just happened to have had the pleasure of doing a bit of consultancy for them over the past 10 years. And yes U can ask what about, but unfortunately due to non-disclosure agreements: 'I could not possibly comment'.
About hearing range: I do not claim to be able to hear 20k either, but I have found it matter's in as much as it expresses something about a drivers transient performance IE. rise time if U like and I can most definitely tell the difference there...
Very best regards
'Dr' O aka a1olsen aka Sven R. Olsen aka a1greatdane
good to hear from U and no worries U can address me almost any way U like (U know - dear child - many names...).
I have seen that very nice looking box previously when reading through the thread(s). There's definately a very competent joiner at large there somewhere... Good to hear there might be a curve potentially coming at some point. There is definitely something going for Large ribbons and small for that matter, but in my main field of Sound Reinforcement work, they do tend to fall in the inadequate bracket, if nothing else, then maybe be course they might actually be to clean for that purpose and therefore present a cultural difference the sound engineers, only with great difficulty can get used to.
A bit more of a 'hands on' explanation, I suppose, as supposed to the more theoretical based one given by Dr. Geddes.
I mean U have as well for this rather large latest system of your creation, chosen to use a compression driver for probably some of the same reasons?
I myself (said the dog) use a couple of very special 1"s incorporating some Radian parts, in my rather large lounge system, be course I could and since I could not within the given economics employ capable enough ribbons or magneto static devices. So I suppose We R a bit in the same boat?
Re. Radian and copper: To my knowledge they only employ copper on their most expensive offerings like the 1" 475. I shall not say for definite, if it's even in the 835. What I do know about that driver, I think all ready posted. I also know it's not in the model down from there; 635? They got their nomenclature a bit mixed, if You really ask Yours truely. I just happened to have had the pleasure of doing a bit of consultancy for them over the past 10 years. And yes U can ask what about, but unfortunately due to non-disclosure agreements: 'I could not possibly comment'.
About hearing range: I do not claim to be able to hear 20k either, but I have found it matter's in as much as it expresses something about a drivers transient performance IE. rise time if U like and I can most definitely tell the difference there...
Very best regards
'Dr' O aka a1olsen aka Sven R. Olsen aka a1greatdane
Member
Joined 2003
Hi Sven,
I agree, true metal ribbon is too fragile for pro application. With the LF support/directivity of a large waveguide, I believe it is possible to achieve the SPL capability I needed for my project. However, I was deterred by the possibility of subwoofers on the same baffle modulating very light ribbons with almost no suspension. (One day I will connect one of compression drivers as a microphone to see the effect of subwoofers on CD.)
It must be quite enjoyable working as a consultant for Radian. I think you could help them a lot by suggesting they do a good job of describing their products (like copper and less smoothing of their graphs). Have you any measurements of their 950 with, I think, 4 or 5 slot phase plug?
Paul
I agree, true metal ribbon is too fragile for pro application. With the LF support/directivity of a large waveguide, I believe it is possible to achieve the SPL capability I needed for my project. However, I was deterred by the possibility of subwoofers on the same baffle modulating very light ribbons with almost no suspension. (One day I will connect one of compression drivers as a microphone to see the effect of subwoofers on CD.)
It must be quite enjoyable working as a consultant for Radian. I think you could help them a lot by suggesting they do a good job of describing their products (like copper and less smoothing of their graphs
). Have you any measurements of their 950 with, I think, 4 or 5 slot phase plug?Paul
Hi Paul,
it has been quite 'enjoyable' enough with going to Ur suggested 'extreme(s)'...
I'm supposedly only an electro mechanical engineer and what does such ones know about Marketing I ask U???
Never mind, - I need to make new 950 measures as well, I'm afraid. The plug is a 5 slit Bob Smith correct one - the only one to my knowledge! (besides the later B&C 1000 unlicensed copy with ill sounding titanium). the TAD4001 & -2 is a 5 slit design, but not Bob Smith correct. The 4003 is a hole with 4 slits (going backwards here - mamma mia!) and Smith actually proved with his very elegant Maths in 1953, that there's no signal coming of the top/centre of the dome or any need for back draft ventilation or other esoteric and otherwise far fetched Irrelevances...
One of the added nice features of Bob Smith plugs are that they allow you quite a lot more magnetic steel near the Voice coil gap and thereby potentially facilitates more flux in the gap...
I do appreciate Dr Geddes claim about the linearity issues, but Smith works for me honestly.
Good point Re. unsupported very light ribbons next to heavy Subs drivers...
'Dr' O
it has been quite 'enjoyable' enough with going to Ur suggested 'extreme(s)'...
I'm supposedly only an electro mechanical engineer and what does such ones know about Marketing I ask U???
Never mind, - I need to make new 950 measures as well, I'm afraid. The plug is a 5 slit Bob Smith correct one - the only one to my knowledge! (besides the later B&C 1000 unlicensed copy with ill sounding titanium). the TAD4001 & -2 is a 5 slit design, but not Bob Smith correct. The 4003 is a hole with 4 slits (going backwards here - mamma mia!) and Smith actually proved with his very elegant Maths in 1953, that there's no signal coming of the top/centre of the dome or any need for back draft ventilation or other esoteric and otherwise far fetched Irrelevances...
One of the added nice features of Bob Smith plugs are that they allow you quite a lot more magnetic steel near the Voice coil gap and thereby potentially facilitates more flux in the gap...
I do appreciate Dr Geddes claim about the linearity issues, but Smith works for me honestly.
Good point Re. unsupported very light ribbons next to heavy Subs drivers...
'Dr' O
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Ohhh - sounds interesting - could you please elaborate some further for the noob?
Thanks
Michael
Without asking you to violate any non-disclosure agreement with Radian, are the 1.4" format drivers (636PB/745PB/835PB) Bob Smith correct, or not? And how many slits do they use - 4 or 5?
Moving away from Radian, what are your feelings on the Altec Tangerine radial phase plug - an improvement on circumferential, or a step backward?
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