Here are some more pictures which I hope will inform you more about the contruction. The first two pictures are of the top cover of the driver comparment. This sits over the large driver. From what I can tell below driver there is a chamber formed by the white 'acoustic material. The tweeter mounts on the three posts shown in the last picture and there is a brass dome in the centre of the triangle formed by the three posts. My next post will detail the tweeter.
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Here are some pictures of the tweeter.The tweeter is 65mm diameter and 30mm deep. I intend to replace it with one of a similar size. Perhaps one of these: https://wilmslowaudio.co.uk/monacor-ideal-treble-units-for-repairs/monacor-dt-25n-diameter66mm
Any thoughts?
Any thoughts?
https://www.visaton.de/en/products/drivers/cone-tweeters/tw-70-8-ohm looks like it may also fit and is a cone tweeter like the original.
Post 43 :
This is a Lorenz tweeter LPH 65 (you did not care to rotate the picture or say it is mm reading,
not inches). I wrote WIGO before, these companies had a cooperation or similar products.
Have a look at Ebay 125876605885
This is a Lorenz tweeter LPH 65 (you did not care to rotate the picture or say it is mm reading,
not inches). I wrote WIGO before, these companies had a cooperation or similar products.
Have a look at Ebay 125876605885
Yes, as far as I can tell these are the same as the ones in the Sugden. Nicely identified. So definately a Lorenz LPH 65. What were these rated at?
So the tweeter sits proud of the baffle board and fires into a a brass diffuser dome.
Replace with a 'cone' tweeter, not a 'dome' tweeter (I have already given three possible candidates in post #35).
Well spotted!
Good afternoon,
I've been working on restoring the Sugdens so thought I'd give you all an update. I stripped the driver housings down and found that underneath the grille there had been fabric, see pics. I removed all the remnants and will repaint the ply housings after filling the screw holes and holes where the stand offs were for the tweeters. As you can see one of the units has had the driver taken in and out a few times. I'm still unsure which of the two 8" drivers are original, but my guess is the Richard Allen Super 8. It has a date stamp of 1969 whereas the other driver is a different - still Richrd Allen, but date stamped 1974. One question I have is about the crossover cap: Given the OG ones are dated 1948 they still read OK when I test them, but never the less I will replace them. For 'authenticity' I was thinking of gutting the 1948 condensers and inserting the nes Monocor caps I have. What do you think to this idea? I've never opened an old condenser is it safe to do so?
I've been working on restoring the Sugdens so thought I'd give you all an update. I stripped the driver housings down and found that underneath the grille there had been fabric, see pics. I removed all the remnants and will repaint the ply housings after filling the screw holes and holes where the stand offs were for the tweeters. As you can see one of the units has had the driver taken in and out a few times. I'm still unsure which of the two 8" drivers are original, but my guess is the Richard Allen Super 8. It has a date stamp of 1969 whereas the other driver is a different - still Richrd Allen, but date stamped 1974. One question I have is about the crossover cap: Given the OG ones are dated 1948 they still read OK when I test them, but never the less I will replace them. For 'authenticity' I was thinking of gutting the 1948 condensers and inserting the nes Monocor caps I have. What do you think to this idea? I've never opened an old condenser is it safe to do so?
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Apologies, I got the dates wrong in the above post. Here are some pics of the drivers from the Sugden's Interestingly the Golden 8 has two date stamps whereas the other speaker only one. There's 8 years between these two drivers and the later one appears to have undergone some value engineering/refinement.
As a side, I have the chance of a Richard Allan class A amp, what's the going proce for these today? It's in quite nice condition, but requires recapping etc.
As a side, I have the chance of a Richard Allan class A amp, what's the going proce for these today? It's in quite nice condition, but requires recapping etc.
The Golden 8 would appear to be the original as the Craftsman Major loudspeaker last appeared in Sugden's price list in 1967 (see post #6).
Your new 2.2 uF cap would suit a nominally 8 ohm cone tweeter. Please tell us, have you chosen a suitable replacement yet?
There's oil inside this type of capacitor that could potentially be hazardous, so best wear protective gloves and glasses to be on the safe side.
However, why bother to stuff these caps for "authenticity" reasons when the tweeters will not be authentic originals?
The price is highly dependent on condition and what someone is willing to pay for it. I can't see any at auction at present, but the price is possibly on a par with a Leak Stereo 30/70.
Unless I were an electronics expert, I would only consider purchasing one descriibed as having been restored and in perfect working condition.
P.S. I believe J.E. Sugden will still service the Richard Allan A21: https://www.sugdenaudio.com/service-repair-centre
P.P.S. Have you tested the mid/bass drivers to see if they are actually working?
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Hi,
I agree re 'authenticity' I'll bin the idea of opening the old caps up. I have chosen the replacment value based on your suggestion 2.2uF.
I have not tested the drivers yet. They look in good condition. I'll test them tomorrow and report back.
As for the Richard Alan amp, I know enough I think to be able to work on it. The reserve was £400 but it didn't make that. What with premium it would have worked out around £520
I agree re 'authenticity' I'll bin the idea of opening the old caps up. I have chosen the replacment value based on your suggestion 2.2uF.
I have not tested the drivers yet. They look in good condition. I'll test them tomorrow and report back.
As for the Richard Alan amp, I know enough I think to be able to work on it. The reserve was £400 but it didn't make that. What with premium it would have worked out around £520
Sorry, I was asking which replacement tweeter you had chosen.
I believe you measured the mid/bass drivers with your ohmmeter. I would expect a resistance reading of 10 to 12 ohm.
That being the case, you should now play music through them to make sure there are no nasty noises caused, e.g., by rubbing voice coils.
I don't know what's in yours in particular but this is worth noting - https://en.wikipedia.org/wiki/Polychlorinated_biphenyl
I read that capacitors containing PCBs were installed in various types of equipment, including telephones, from the late 1930s to the 1970s:
https://telephonecollecting.org/articles/PCBs Sept 15.pdf
Nasty stuff. Just as well Dr Smith has binned the idea of opening the old capacitors up!
https://telephonecollecting.org/articles/PCBs Sept 15.pdf
Nasty stuff. Just as well Dr Smith has binned the idea of opening the old capacitors up!
Good afternoon,
Update: these are the tweeters I purchased as replacements for the Sugden tweeters (lorenze). I intend to use a 2.2uF cap as the crossover.
The other picture is of the driver housings which I've resprayed. I'm just waiting for the standoffs for the tweeters to arrive then I'll assemble the speakers. I tested both 8inch drivers and a quick full spectrum sweeo appeared to sound fine. So fingers crossed the drivers are fine.
p.s. I didn't end up buying the Richard Allen A21...although I'm still tempted : )
Update: these are the tweeters I purchased as replacements for the Sugden tweeters (lorenze). I intend to use a 2.2uF cap as the crossover.
The other picture is of the driver housings which I've resprayed. I'm just waiting for the standoffs for the tweeters to arrive then I'll assemble the speakers. I tested both 8inch drivers and a quick full spectrum sweeo appeared to sound fine. So fingers crossed the drivers are fine.
p.s. I didn't end up buying the Richard Allen A21...although I'm still tempted : )
Using a series 2.2 uF with an 8 ohm tweeter means the treble output will start to roll off slowly (at the rate of 6 dB/octave) below 9,000 Hz.
However, the treble level will be well down at the cone tweeter's resonance frequency of 1,500 Hz, so the tweeter should be reasonably safe from overload in this low power vintage system.
I hope that the tweeter's mean sound pressure level of 90 dB/W/m will be loud enough to provide a reasonable match for that of the Richard Allan drivers.
P.S. Nice restoration work on the "driver housings" or baffles.
