Hello All,
I am the new owner of a pair of Radford 360s which are in a bit of a sad state.
For those of you not familiar with this model. It is an omnidirectional speaker made by Radford consisting of two 10inch drivers that fire to the side feeding into a transmission line cabinet exiting the front at the base of the cabinet. Above this are 4 4inch paper coned mid-bass drivers and 4 tweeters each mounted on each side of the speaker giving one 360 degrees of sound. These were sold in kit form, from what I understand, not too many made it to the States but in Canada and the rest of the World they were more common.
At present 5 of the 8 mid-bass drivers and tweeters are functional but even at that, these speakers are impressive. The bass goes low and the dynamics are punchy. What they lack in precision they make up for in musicality. 🙂 I'm hoping that restoring the functionality will help in the precision department.
What I would like to do is update the cabinets with more modern drivers. The original ones are not easy to find and I'm sure that in the 40+ years since they were made, improvements in speaker design have been made. Information on the net is scarce and am hoping that you can also help me find out more about these speakers as well.
Yes, I'm aware that I'll need to update the crossover as the original mid-bass drivers had a dip in them. I have a friend who is well versed in cross-overs who can help me with that.
First step, replace the mid-bass drivers and tweeters. I need 8 of them... and this is a cost *is* an object project so if we could try and keep it under 500$, it would be appreciated.
I was thinking maybe the Vifa TC9FD18.
Peerless by Tymphany TC9FD18-08 3-1/2" Full Range Paper Cone Woofer
I'm guessing that to try and keep in character with the speaker, a similar driver (paper coned) should be sourced Yes, it's 3.5 inch instead of 4 and full range, but available in 4 or 8 ohm and well thought of. But honestly, I really don't know. Hopefully those with more experience can speak up.
Second step, replace the 10inch drivers in order to try and tighten up the bass a bit (but this is down the road.)
I'm hoping that posting here I won't send anyone into a tizzy about mangling some great hierloom. (They're already mangled. 🙂 ) I'll keep all the original components and would be able to reverse my little experiement if need be.
I'd just like to see if I can take them a step further.
Thank you all for your input.
Andre
I am the new owner of a pair of Radford 360s which are in a bit of a sad state.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
For those of you not familiar with this model. It is an omnidirectional speaker made by Radford consisting of two 10inch drivers that fire to the side feeding into a transmission line cabinet exiting the front at the base of the cabinet. Above this are 4 4inch paper coned mid-bass drivers and 4 tweeters each mounted on each side of the speaker giving one 360 degrees of sound. These were sold in kit form, from what I understand, not too many made it to the States but in Canada and the rest of the World they were more common.
At present 5 of the 8 mid-bass drivers and tweeters are functional but even at that, these speakers are impressive. The bass goes low and the dynamics are punchy. What they lack in precision they make up for in musicality. 🙂 I'm hoping that restoring the functionality will help in the precision department.
What I would like to do is update the cabinets with more modern drivers. The original ones are not easy to find and I'm sure that in the 40+ years since they were made, improvements in speaker design have been made. Information on the net is scarce and am hoping that you can also help me find out more about these speakers as well.
Yes, I'm aware that I'll need to update the crossover as the original mid-bass drivers had a dip in them. I have a friend who is well versed in cross-overs who can help me with that.
First step, replace the mid-bass drivers and tweeters. I need 8 of them... and this is a cost *is* an object project so if we could try and keep it under 500$, it would be appreciated.
I was thinking maybe the Vifa TC9FD18.
Peerless by Tymphany TC9FD18-08 3-1/2" Full Range Paper Cone Woofer
I'm guessing that to try and keep in character with the speaker, a similar driver (paper coned) should be sourced Yes, it's 3.5 inch instead of 4 and full range, but available in 4 or 8 ohm and well thought of. But honestly, I really don't know. Hopefully those with more experience can speak up.
Second step, replace the 10inch drivers in order to try and tighten up the bass a bit (but this is down the road.)
I'm hoping that posting here I won't send anyone into a tizzy about mangling some great hierloom. (They're already mangled. 🙂 ) I'll keep all the original components and would be able to reverse my little experiement if need be.
I'd just like to see if I can take them a step further.
Thank you all for your input.
Andre
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Hi, your friend should be able to analyze all the system then.
First, check for impedance of each driver.
See if they are series/parallel connected. I'm thinking of the available drivers that are used for arrays and are 16 Ω, so for a parallel of four units you'll have nominal 4Ω.
The images doesn't show, and searching on the net I get only Sansui SF-1🙄
Thinking along the line...omnidirectional and pro drivers, the ones that are used in arrays:
both things that I don't like, but... Nowadays you can have some very powerful midrange units that probably weren't available at that time, same for the tweeters.
So you could turn the speaker into a forward-only emission type by closing three holes for the mid and use one tweeter...
Dynaudio 1000 W peak units come to mind
1000 W !? Naaaahhh
both things that I don't like, but... Nowadays you can have some very powerful midrange units that probably weren't available at that time, same for the tweeters.
So you could turn the speaker into a forward-only emission type by closing three holes for the mid and use one tweeter...
Dynaudio 1000 W peak units come to mind
1000 W !? Naaaahhh
I forgot the double woofers at the sides...well, that's nowadays considered to be good practice, right ?
🙄
I can't see the pictures, so I'm working blind here. But the first thing you do when replacing drivers is measure the cutouts in the woodwork to see if anything fits. You also measure the DC resistance of the drivers. And note what the cones are made of. Usually plastic polycones or paper.
Then if you get lucky, you might find something similar looking that works much the same way.
Try uploading your images as small jpegs to the forum, if you have the priveliges. It's the paperclip symbol that does this.
It's actually a bit odd if just a few of the drivers have failed, since they presumably work under the same conditions. You might just have a dry solder joint or failed old electrolytic NP capacitors. The visual inspection of the wiring always helpful! Corrosion creeps in too, so tighten everything.
Then if you get lucky, you might find something similar looking that works much the same way.
Try uploading your images as small jpegs to the forum, if you have the priveliges. It's the paperclip symbol that does this.
It's actually a bit odd if just a few of the drivers have failed, since they presumably work under the same conditions. You might just have a dry solder joint or failed old electrolytic NP capacitors. The visual inspection of the wiring always helpful! Corrosion creeps in too, so tighten everything.
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Sorry for the delay, I was on holiday. The images should be fixed now.
My friend who is handy with crossovers tested the speakers and tells me that they are out of spec. So... to start I'm looking for a 4inch paper coned midband driver that won't break the bank as I'll be replacing 8 of them.... Any suggestions?
My friend who is handy with crossovers tested the speakers and tells me that they are out of spec. So... to start I'm looking for a 4inch paper coned midband driver that won't break the bank as I'll be replacing 8 of them.... Any suggestions?
Please post the specs that your drivers are no longer matching. This will make it much easier to find similar, hopefully better, current drivers. But measure your driver holes yourself, worn tooling causes variations in physical dimensions. Don't worry about woofer placement, with 4x4" mids your low/mid xover should be low enough for the woofers to be operating in 4pi space(full omni).
Looks like fun! I know that I have enjoyed the Epicure 4-sided omnis that I have worked on.
Looks like fun! I know that I have enjoyed the Epicure 4-sided omnis that I have worked on.
The Woofers & midranges were made by Goodmans. the Tweeter by Peerless. I’d keep the woofers, you can probably tighten things up by cleaning up the damping. You will be sadly dissapointed if you use the TC9, it is kinda lifeless. The TG9 might be a better bet, i finally have a set to listen to so reserve judgement. My first thot was to replace the stuff on the top with a good FR on each side, but it will push your budget to get ones good enuff (ie 8 Mark Audio 6.2x or all out Mark Audio 7.3). Going this way would simplify the teaking of the XO. If you went active (beam) the XO issue would be greatly simplified and an amp directly connected to the bass drivers might go a long way to tighting things up.
The Radford S90 was the speaker that started me on a lifetime of exploring TLs. From hearing them in the little hifi store tucked into the walkways of the Westbrooke Mall in Calgary. That led to meeting the guy building the boxes for them. He ended up being one of my gurus, and may have more information on the 360 for you. If you’d like to contacy him email and i’ll see if he is open to cooresponding (likely).
dave
The Radford S90 was the speaker that started me on a lifetime of exploring TLs. From hearing them in the little hifi store tucked into the walkways of the Westbrooke Mall in Calgary. That led to meeting the guy building the boxes for them. He ended up being one of my gurus, and may have more information on the 360 for you. If you’d like to contacy him email and i’ll see if he is open to cooresponding (likely).
dave
Thanks for all the suggestions. The midranges are 4in (measured) 8ohm paper coned units. From what I understand, 2 are wired in series and 2 in parallel.
I think that for the moment I want to stay with a passive crossover as I'm keeping my mini-dsp for another project where I hope to marry a set of 10in Tannoy dual concentrics with a set of ripole subs I built.
I would gladly take you up on your offer on contacting your mentor Dave. The idea of the fullrangers instead of midband and tweeters is interesting as well. I had a bad experience with the Alpair 7.3 in a pair of Frugalhorns though and had a basket crack on me... Twice. 🙁 ( I'm guessing that my screw holes weren't perfectly aligned and that stressed the basket and caused it to crack. ) I'm guessing you prefer the Mark Audio drivers over the Fostex equivalents.
What about the 4 inch Dayton Audio? Dayton Audio RS100-8 4" Reference Full-Range Driver
This could be a possibility.
-andre-
I think that for the moment I want to stay with a passive crossover as I'm keeping my mini-dsp for another project where I hope to marry a set of 10in Tannoy dual concentrics with a set of ripole subs I built.
I would gladly take you up on your offer on contacting your mentor Dave. The idea of the fullrangers instead of midband and tweeters is interesting as well. I had a bad experience with the Alpair 7.3 in a pair of Frugalhorns though and had a basket crack on me... Twice. 🙁 ( I'm guessing that my screw holes weren't perfectly aligned and that stressed the basket and caused it to crack. ) I'm guessing you prefer the Mark Audio drivers over the Fostex equivalents.
What about the 4 inch Dayton Audio? Dayton Audio RS100-8 4" Reference Full-Range Driver
This could be a possibility.
-andre-
email sent to him.
It is true that it is possinble to crack the Alpair baskets if you tighten the screws too much. Properly installed they are still my favorite driver (A7.3eN)
The FF105wk would be the direct competirion and it is also pretty good. Doesn’t go as low, but is more efficient.
No experience. I have a bit of an aversion to PE’s housebrand having heard stories of how they treat there OEMs. The people who have used this driver do seem to like it.
dave
I should also mention the Mark Audio Pluvia 7. Th enew basket is much tougher and you can get away without a rebate. Cheaper too. It has much the same sonic signature as the A7.3 but is not capable of reproducing the same level of detail.
dave
dave
Despite being the above referenced 'guru' I don't know that I have much to add here. Although I built at least 100 pairs of the Studio 90 I think I might have done only 3-4 pairs of the 360s and don't know that I ever actually heard a pair.
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