I have four of the 15nlw9500 and I will indeed use them for HiFi but in a three way configuration. It is a very nicely built driver but I am not sure whether it is wise to use them above 500 Hz for high-quality reproduction.
The 15NLW9300 looks like the bigger brother of the 12nlw9300 and it could be crossed higher than the 15nlw9500 but LF exension-wise there is no big advantage over the 12nlw9300. I think this is the one that is used in the Unison MAX 2.
15" drivers that can do both - go low and reach into the mids nicely (i.e. usable for a high quality two-way) - are very rare.
Regards
Charles
The 15NLW9300 looks like the bigger brother of the 12nlw9300 and it could be crossed higher than the 15nlw9500 but LF exension-wise there is no big advantage over the 12nlw9300. I think this is the one that is used in the Unison MAX 2.
15" drivers that can do both - go low and reach into the mids nicely (i.e. usable for a high quality two-way) - are very rare.
Regards
Charles
Dear all!
Some members of this forum several times mentioned the Radian 745Neo compression driver in this thread. I searched for impedance curves of this driver in common CD horn or comparable.
The datasheet from the vendor shows a really impressive frequency response up to 20 kHz but not with the used horn combination and no impedance curve at all. Furthermore, no values for DCR of the 8 or 16 Ohms versions.
If someone could provide these informations it would be great!
Is Beryllium really that much better than Aluminium as many say? Expensive...
Thanks in advance!
Bernd!
Some members of this forum several times mentioned the Radian 745Neo compression driver in this thread. I searched for impedance curves of this driver in common CD horn or comparable.
The datasheet from the vendor shows a really impressive frequency response up to 20 kHz but not with the used horn combination and no impedance curve at all. Furthermore, no values for DCR of the 8 or 16 Ohms versions.
If someone could provide these informations it would be great!
Is Beryllium really that much better than Aluminium as many say? Expensive...
Thanks in advance!
Bernd!
FYI, the impedance curve is irrelevant if the driver is padded down significantly using an L-Pad or - better - a shunted autoformer in the passive crossover.
And Be is better than Al or Ti, but the differences are subtle (law of diminishing returns...)
Marco
Somewhere, maybe this thread, there were measurements of the resonances of Ti, Al, and Beryllium. Aluminum looked so close that I can't think the cost of Beryllium is worth it. But I have nor heard them.
Did see the new Radian drivers at a show. They keep getting smaller and smaller.
Did see the new Radian drivers at a show. They keep getting smaller and smaller.
Pano:
Gary Dahl is bringing his system to the 2017 PNW DIY Audio show this Summer for those that would like to hear it in person. He's done some major work on it and I've been told that it's sounding better than ever (I've not heard this latest version myself).
Best Regards,
TerryO
Hello Marco!
I think a little bit different about impedance behaviour. At least the range of the self resonance should be provided. Where is the problem for any vendor to provide RDC of the voicecoil and minimum impedance? Not really much effort.
Radian is providing a frequency response in the datasheet but not with which horn this was measured. Look at the datasheet of JBL 2447H driver. Nearly everything one needs to know about a driver.
I think a little bit different about impedance behaviour. At least the range of the self resonance should be provided. Where is the problem for any vendor to provide RDC of the voicecoil and minimum impedance? Not really much effort.
Radian is providing a frequency response in the datasheet but not with which horn this was measured. Look at the datasheet of JBL 2447H driver. Nearly everything one needs to know about a driver.
The response of a passive network is heavily influenced by the compression drivers impedance. This impedance can be very complex and is highly dependent on the horn that it is mounted to. This makes generalizations about the effect very difficult. It's best to use actual in-situ measured impedances.
Hi Pano,
I think JBL 4" Ti-SL (dusted) diaphragms are the best compromise solution concerning the characteristics and the price.
Regards
Ivica
Radian 745Neo impedance curve is in the spec sheet:
745Neo Compression Driver - Radian Audio
However I would agree with everyone else telling you that it's highly dependent on the horn.
745Neo Compression Driver - Radian Audio
However I would agree with everyone else telling you that it's highly dependent on the horn.
Many thanks for the link!
A week or so ago thie datasheet was not there. Maybe it happened because of my request to Radian with no response up to yet. Look at the filename behind the link ;-)
745NeoPB-data sheet-final 070817.pdf
A week or so ago thie datasheet was not there. Maybe it happened because of my request to Radian with no response up to yet. Look at the filename behind the link ;-)
745NeoPB-data sheet-final 070817.pdf
Sure it is. BUT, once you've multiplied that impedance by a factor of ~100 with an autoformer (to obtain -20dB of attenuation) and placed, say, an 8 Ohm shunt resistor across it, then it will behave as an almost ideal resistor (of approx. 7.9 - 8 Ohms). This is what I meant.
BTW: does anyone from the German people posting here know wether there is a source for the 745 in Germany.
I checked with Thomann who have some Radians in their portfolio but they told me that they can´t supply the 745´s.
Thanks and Regards
Claus
I checked with Thomann who have some Radians in their portfolio but they told me that they can´t supply the 745´s.
Thanks and Regards
Claus
Behringer electric sell the Be-equipped version (475PB Be):
Radian 1" 475PB Beryllium
I dealt with them in the past (had them install Truextent Be diaphragms in my JBL 2450J drivers), and can vouch for their professionalism.
Marco
Hello Claus!
So far as I know Behringer is no official distributor for Radian, They have only a few models for which thay mount their Be diaphragms.
Does anybody know who is the offcial distributor for europe or in special for germany - if exist. The Radian site is not very informative with respect to this.
Thanks!
So far as I know Behringer is no official distributor for Radian, They have only a few models for which thay mount their Be diaphragms.
Does anybody know who is the offcial distributor for europe or in special for germany - if exist. The Radian site is not very informative with respect to this.
Thanks!
From the Radian website:
Thomann GMBH
Hans-Thomann-Straße 1
Burgebrach,
96138
Germany
Website: Welcome - Thomann International
Email: mailto:international@thomann.de
Phone
+49-9546-9223-55
Please keep in mind that the data sheet provided by Radian for the 745NeoPB is for the aluminum-diaphragm version. As far as I know, Radian has not published data sheets or response curves for any of their Beryllium-equipped drivers.
The frequency response of the 745NeoBe isn't as flat as the aluminum version. In my experience, the use of beryllium diaphragms makes frequency shaping a requirement. The advantage one gains is the reduction of breakup in the audible range of treble frequencies. According to Materion, it has better self-damping than aluminum, and its stiffness moves the breakup to a higher frequency range.
The 745PB (ferrite magnet) that I started with had relatively flat frequency response, but the upper octaves didn't ever sound right with strings, same problem that I had experienced with Altec and GPA units. The 745NeoBe was the first compression driver that I ever heard produce the sound of strings convincingly. A further benefit was that with frequency shaping, I didn't find it necessary to use a tweeter.
In my most recent experiments, I have been enjoying the sound with Yamaha JA6681B drivers. These don't require frequency shaping, but it has been necessary to put the RAAL ribbons back to work. Although their diaphragms are aluminum, the Yammies don't seem to have the same sonic issues I am used to hearing with aluminum...but time will tell.
The frequency response of the 745NeoBe isn't as flat as the aluminum version. In my experience, the use of beryllium diaphragms makes frequency shaping a requirement. The advantage one gains is the reduction of breakup in the audible range of treble frequencies. According to Materion, it has better self-damping than aluminum, and its stiffness moves the breakup to a higher frequency range.
The 745PB (ferrite magnet) that I started with had relatively flat frequency response, but the upper octaves didn't ever sound right with strings, same problem that I had experienced with Altec and GPA units. The 745NeoBe was the first compression driver that I ever heard produce the sound of strings convincingly. A further benefit was that with frequency shaping, I didn't find it necessary to use a tweeter.
In my most recent experiments, I have been enjoying the sound with Yamaha JA6681B drivers. These don't require frequency shaping, but it has been necessary to put the RAAL ribbons back to work. Although their diaphragms are aluminum, the Yammies don't seem to have the same sonic issues I am used to hearing with aluminum...but time will tell.
Just a reminder to those in the Pacific Northwest, on the last Saturday in August, Gary will be playing is speakers and gear at the PNWAS/ Sound DIY Club DIY Audio get-together on Mercer Island, Washington. Best of all it's free to get in and parking is as well.
Best Regards,
TerryO
Best Regards,
TerryO
Gary will be demo-ing not just the speakers, but the Amity push-pull 300B amplifier with a first-of-its-kind Tribute interstage transformer optimized for 6SN7 drivers. (The 6SN7 is difficult to design for because of relatively high output impedance, compared to a 5687, 6900, 7119, or ECC199.)
Speakers with large-format beryllium diaphragms (or the famed Yamaha JA6681B drivers), alnico-magnet Altec/GPA 416's, and 425 Hz LeCleac'h horns aren't that common at the hifi shows, so I'd advise anyone who's curious about the concept to show up and give a listen.
Maybe not as dramatic as the solar eclipse on the 21st of August, but I think you'll all have a good time at the PNWAS get-together! Have fun, guys!
Speakers with large-format beryllium diaphragms (or the famed Yamaha JA6681B drivers), alnico-magnet Altec/GPA 416's, and 425 Hz LeCleac'h horns aren't that common at the hifi shows, so I'd advise anyone who's curious about the concept to show up and give a listen.
Maybe not as dramatic as the solar eclipse on the 21st of August, but I think you'll all have a good time at the PNWAS get-together! Have fun, guys!
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