Royd RR3 Replacement Drive Units
As I understand it, Revelation bass drivers are somewhat unique, either being modified (from what I don't know - does anyone have an idea?), or custom made. The tweeters, though, are Vifa units. Having dismantled one, I can't see it being modified in any way ( although Joe did modify other tweeters he used).
The original tweeter is this: Vifa D26NC - 15 - 06. It is a 6 ohm unit, and also has the following numbers on it: 27022002 (probably manufacturing date - 27 feb, 2002).
There is a very useful page here, explaining how to understand the Vifa codes. It seems that the '15' element of the code is a customer code, so the manufacturer 'customised' the tweeter for clients. The only thing that seems to change is the face-plate.
I have been in touch with the manufacturer (Vifa has been bought by Scanspeak), who directed me to their main distributor. There I was told there are no D26NC-15-06 left now.
Some research has revealed that this particular tweeter was replaced by another variant, the D26NC - 55 - 06.
This tweeter has slightly different specification, but appears to be an improved version of the Revelation tweeter, release a little later. Look at the two PDF data sheets, here:
- D26NC - 15 - 06. (Old)
- D26NC - 55 - 06. (New)
It seems every electrical and mechanical measurement is identical between the two tweeters. More interestingly, look at the freq plots. The later tweeter (DN26-55-06) has a slightly smoother response; the peak around 14 - 16khz is flatter.
It seems reasonable to conclude the newer Vifa is a better choice, and Royd may very well have fitted them had they been available (or cheaper?) at the time the Revelation series was designed.
Sadly, the Vifa D26-55-06 is also out of production now. After Vifa stopped making it in house, it was produced under license in China, as far as I can tell. It had the exact same specifications, and one assumes Vifa kept tight quality control over their design.
There are a number (78, as of today) of new, Chinese manufactured Vifa D26NC-55-06 available from Solen, in Canada. I bought a pair myself, and they arrived at reasonable cost (just under £50GBP).
I have compared them with the very last D26-15-06 from the factory (I bought that as well - sorry!), and they seem identical so far. I shall measure them again shortly, they have been running for several weeks now.
One last thing - a slight hitch: The circular heatsink of the Chinese made D26-55-06 is slightly larger that the square one of the in-house Vifa units. The inner hole, behind the faceplate rebate, on the RR3 cabinet is slightly too small to insert the D26-55-06. I enlarged mine carefully with a sharp Stanley knife, carving away the corners. Also, the faceplate is a little tight, but can be 'persuaded' to fit without surgery. All is now well, and I have brand new tweeters in my RR3.
Comments
I think the ones on my RR1's are smaller ones at only 19mm but might be an interesting experment to try a pair of these in them. There again Joe Acyroyd did know what he was doing and playing around with his design/specs could be ill advised.
But the mid/bass drivers in the RR1 is far as I know is the same 5in one in all 3 Revelations albeit the RR3's seem to have pointy end cones.
I am struggling to remember if they are the same across the range, I know I asked but it was a couple of years ago. Throughout the rest of the Royd ranges, each driver was unique even though they looked the same.
Sometime, when you're feeling brave, why not pop one of your tweeters out and read the label for us?
Also, the RR1 crosses over at 5khz, whereas the RR2 and RR3 cross at 4.5khz (and the RR2 appears to share the same tweeter as the RR3). Seems to be a slightly different beast.
Will pop out the tweeter one day when feeling a bit gung ho !
I haven't got far with the woofers; I have my old blown unit which I have dismantled completely. It is almost certainly a Scanspeak unit, but doesn't match anything they ever had on sale.
The basket can still be found on the 10cm full range drivers, and in fact the cone may be used on them also. It is a 10cm paper slice cone with a (very very rare) 19mm voice coil on an aluminium former.
There is also a double magnet assembly on the back, which can be removed from the basket.
It looks as if the driver was made to Royd's specs either at Scanspeak or Royd HQ, using Scanspeak parts. The unknown elements are:
I may yet send my ripped up driver to somewhere like Wembley loudspeaker repairs and see if they can reverse engineer the remaining parts of the puzzle. I can always supply a working unit for examination.
Anyone got any observations/helpful suggestions?
That's really useful info, thanks! Anything else you recall (or old contacts you could ask) would be received with genuine interest.
The basket initially looks to be Scan-Speak, as does the cone itself. Also, Scan-Speak have made a few drivers with 19 nor 20mm voice coils, so it currently seems a pretty good bet the drivers were made up from S-S parts. To that end, I have an email enquiry pending with the distributors to see if anyone recalls dealing with Royd, or recognises the driver.
However, a Dynaudio lead is a good one. I haven't yet been able to track down an appropriate candidate on google yet, but I will try x-checking with Totem drivers as well. Thanks for your input.
I have had a reply from the man at the Europe distributors, this is what was said:
More investigation needed, methinks.
Duke ( @JD ) - I have looked at the Totem Arro driver. There is quite a bit of controversy around that driver, it seems some early models were Dynaudio but later they used a cheaper remake. Nontheless, it is a different driver as far as I can see, a different basket for a stert (The S-S basket in the link above is undoubtedly the correct one for the RR3, whether the RR1 and 2 used different would be interesting to know), also bigger voice coil and different cone.
Would you by any chance be able to chase up any of what you remember with your old contacts please? It may be the best lead left for the time being.
In the mean time, I am thinking about sending one of my working drivers to someone who can measure every electrical and mechanical parameter for me, and see if a custom driver manufacturer can make something up. My guess is that this route would be prohibitively expensive, but I would like to see.
Does anyone have any suggestions at this point?
Just saw your message. There is a chance that replacing the ferrofluid in the tweeters would restore things. If you unclip the heatsink at the rear, you'll find the faceplate is integrated with all the 'front' of the tweeter. When you remove it, the voice coil will come out of the magnet with it. It all clips back together just fine.
I don't know if ferrofluid drying out causes the lack of output, but could be worth a try. I believe you just inject it in.
I am currently using one NOS replacement tweeter, and one of the later replacements (which should be technically better). I can detect no difference at all between them, so I can recommend the newer units from Solen. (I think it's the same tweeter as found in the ATC SCM35).
If you only need one though, I can drop in the other Solen replacement I bought, and send you the correct NOS unit. It's only been in a couple of months. However, you may just find that the other tweeter is down also, once a new one is installed...
Thanks
Steve
I'll PM you in a minute, it'll be easy to reply then.
If you are sure it's the same tweeter (I would be very surprised if it wasn't) then we're sorted. The NOS tweeter was £58 with shipping. Given it's now 'second hand' (sort of), you can have it for £30 delivered. I'll just need an address.
In so doing I thought I'd take a few photos of the insides of the speaker, just to give an idea of the construction of these speakers. They really are very heavy indeed for their small size.
Dismantled.
This shows the thickness of the cabs, thicker than the penny.
The steel plates inside the cabinets, and the port-tube.
As above, from a different angle.
Here we see the thickness of the metal plate, approximately 4mm.
The upper binding posts, with tweeter protection (such as it is). The internal links can be seen dropping toward the lower binding posts - I removed these and bought the red & black wires up to the upper binding posts.
Rear view of the uprated tweeter, notice how tightly it fits. You can see where the inner hole had to be re-shaped with a sharp chisel and a stanley knife. Also, part of the crossover, which is mounted to the top of the cabinet.
The rest of the crossover. Not much too it, but this still has more individual components than other Royds I have seen. Jo Ackroyd described this as a "modified first order crossover".
The small main driver that has been custom built and voiced, and cannot be replicated (so it seems at this time).
Rear view of the driver, showing the heavy canvass wrapping that is heavily glued on.
These are 'simple' speakers, but it seems they are anything but a simple design, from the custom built mid-bass driver to the unique crossover to the unusual cabinet construction. I wonder what Joe Ackroyd might have come up with given more time and resources? I should love to have heard a substantially bigger variation, but given what he says in his article here, perhaps Joe knew the magic was in the small drivers.
This is what he said in the little note he wrote, which came with all the Revelation speakers:
I have had a quick look at the SEAS site, and I guess several of the drivers have potential to form the basis of a re-worked RR3; they look like fine quality engineering, with exceptional characteristics for small drivers. Maybe they get a good deal of the way 'there' as standard units, without the remodelling Royd did.
I wonder if it isn't possible to send away a working driver to somewhere and get a complete suite of measurements done, and then have a custom unit built. Expensive, but it may be the only way.
Maybe so. I always suspected the Sorceror didn't lose much to the RR3, a head to head would be interesting.
I heard RR1s today, on the end of a Magnum 250 & Lakewest MDAC - it was close to perfection. Bravo, Joe (and Colin).
I've been trying to get some big old monitors to catch up with the Royds, I recently updated the X-over with fast caps and Clarity caps, but no dice...
Funny what you say about the immediacy of the Sapphires, that's precisely what Justin & I were discussing last week. No loss at all with the Revelations, and gains everywhere else so long as they have suitable amplification. I love them - and the RR1 for that matter.
They are power hungry, Neil, so I'm also not surprised they respond to BiAmping.
IMO they're worth the top end of that, but they are so unusual not many people know of them/want them. Of course, for a good price you need 2 or 3 people to want them at once.
£15 each, less than half the price of other retailers...
Do you remember the voltage / capacitance rating of those yellow electrolytic caps? I want to send mine in for a service, replace the tweeters, and replace the electrolytics like-for-like. Thanks.