C-60 Sovereign restoration

[yggdrasil]

All the drivers fit right back in.

[yggdrasil]

In daylight.

[yggdrasil]

This is what's left of the biggest wound in the veneer.

[yggdrasil]

First I did 2 coats of lacquer.


Then I added the specks. Used a toothbrush.

Then I added a little color to the lacquer, thinned it a lot and added 14 coats...

Finished up with 2 coats of lacquer to give them a little glow.

I have played them a little now, and the first impressions are great.

But, will have to do something with the crossovers, probably build new ones.

[yggdrasil]

These babies have been playing a few days now. I'll try to make a short summary.


Bass response is fast, with a good punch. Not quite as low as my much larger DIY's, but still very good.

Midrange is very dynamic, quite hard, with the ability to scare the shit out of the listener.

The high frequencies feel cramped.

What now?
My thoughts with these speakers was to keep them original, or at least very close to original.

Rebuilding the crossovers with new, high quality components will do something with both the midrange and high frequencies.

Do you have any recommendations/thoughts?

[Ken Pachkowsky]

Ya did one heck of a good job on those. Congratulations

Its obvious you spent many hours on it.

Ken

[yggdrasil]

You've got what, LX5 and N7000?

Point being, I'd want to be able to restore everything to original at a later date.

Thanks for your input Zilch.

Yes, it is both LX5 and N7000.

And yes, I want to be able to restore everything to original.

In this step I am going to look at the crossovers. I have some ideas. At this stage it is more questions than answers, and a hell of a lot more complicated than the work intensive cabinet restoration.

• Build new crossovers and put the old ones aside.
• Rearrange them to avoid two crossovers in series.
• Maybe change crossover frequenzies.
• Maybe upgrade to newer design/other slopes.

I will be listening to them a lot since they have been placed in the living room, hooked up to the TV and everything...

[Zilch]

Consider using full active crossovers with them. That way you can adjust everything until you get them sounding the way you like.

The 375 is acting as a direct radiator at the lower frequencies on that short horn....

[yggdrasil]

Not a bad idea. Then I would be have to collect some more gear!

Used an Accuphase vintage electronic crossover ten years ago. Changed to passive with a very good result. Sold the Accuphase afterwards.

[yggdrasil]

As I had the test equipment hooked up it was time to see if there was hard evidence to my ears scepticism....


I have set the LX-5 to lowest positon. The woofers has no chance of keeping up with the 375's.

In the first graph the N7000 have been set to minimum, i.e. only LE15 and 375 in this picture. Sampling rate is 48KHz.

Notice the top at 7KHz and the shift at 3KHz.

In the second graph I have set the sampling rate to 22KHz in order to emphasize the mid and lower frequenzies. I allways felt they are a bit thin.



It seems there has to be done some serious work on new crossovers.

[Caledon Ken]

I realize this thread has been quiet for years but as my topic fits I thought I would post here rather than starting new thread.

I have a couple of Sovereign C60 S8R's, serial # 10892 and 10893. ( I tried to find that database someone was starting so I could add them and the components.) I live outside of Toronto Canada. I have some of the original instructions that came in an envelope on the speakers. They used to be attached to a very large Macintosh system which unfortunately is long gone.

Suffice to say they have been in the family for years and need some obvious work on the cases, especially the tops and bases. Not sure but was thinking of removing and replacing veneer.

In reading these forums it sounds like they also have to be reconed. They work at a basic level and they are used regularly. Twenty ones years ago I replaced one of the LX5's. Had to turn in the original as part of the fix.

I have some basic questions I was hoping to have answered to help me decide on a path forward... restore or leave alone.

1) For those that have restored the cases, about how many hours of labor did it take? Did you strip veneer or just rework?
2) Assuming a I get the pair of LE15A's reconed about how much should this cost?
3) Would I also need to get the PR15's done?
4) Are here any known pitfalls I should watch for in getting the above reconed? (Everyone you call is an expert and given these are forty plus years old most experts weren't even born.)

I'm reasonable good with my hands and electronics although I would be considered a rookie from what I read on these forums. Lot of very dedicated people.

Any advise, help or comments would be greatly appreciated.

[HCSGuy]

First, post some pictures and LH members can give you input on the veneer.

I will give my input on the LE15's, as I have already travelled that road. I assume yours have the yellow "Lansalloy" surrounds, that harden over time. If yours have hardened but not cracked, you can try carefully softening them up with brake fluid - do a search on this forum for more info. If they have cracked, but the spider is flat and they are otherwise intact, you can replace the surround with a new foam one, which I'd recommend you have professionally done for your first one, as your drivers are valuable. If they have not been subject to moisture and the spider is flat, you shouldn't have to recone them just due to age. If you choose to have them reconed, make sure you specify (get it in writing) that a factory JBL kit is to be used, and also that it specify the impedance - yours are probably 16ohm, so make sure the 16ohm kit gets installed or your crossover point will change. A recone is probably $300 these days, and you may have to wait a while for a kit, if they are still being produced (I had to wait 6mos, but this was about 8yrs ago). Again, if you post pictures, you will get valuable feedback.

The PR15's should not need any work - your vintage should have the folded fabric surround that holds up fine.

Hope this helps...

[Caledon Ken]

Thanks for the info.

The PR15's do have a sticky black fabric cloth where the yellow "Lansalloy" would be on the LE15A's. Apart from some cat hair from long ago and some real spider webs they look fine. Should be a pain to clean but doable.

The LE15A in what I will call the left hand cabinet, the 075 on the left, is showing minor cracks. The rest of the speaker looks good. I opened the case, by removing the PR15, and the spider looked okay but I did not remove. The LE15A on the right hand cabinet unfortunately is showing more age and there is a large crack around six inches long at the very edge. It shows bigger hair line cracks.

If I go with recone is that a "Lansalloy" replacement and replacement of the spider or just the "Lansalloy" for $300? Thanks for the advice on the JBL specific parts. If I proceed I will heed this advice.

I guess the bigger question is what do I do if JBL parts are not available? Is there another quality replacement?

I've taken your advise and I have included photo's of the enclosure tops. Everyone will notice these cabinets are dark brown. They have been in my possession for twenty five years and I did not refinish them and I can say with almost 100% certainty that my brother in-law did not refinish them. He just wasn't the type. I want to make them a dark reddish wood grain to match some other units I have.

[HCSGuy]

I assume you mean cracks in the Lansalloy surround, and not tears in the actual cone. If the Lansalloy is cracked, it is not repairable and needs to be removed and replaced with new aftermarket foam, which my tech charges me $50 per driver to do. $300 is my estimate to replace the cone assembly (Cone, surround, and voicecoil) - if you have a really good tech who can recharge the magnet at the same time, you'll basically have a new woofer. Le-15A's don't degauss from use, but maybe overtime the magnet has lost some strength - I'm not sure I'd worry about it unless your tech has the facilities to do something about it. When they replace the foam, have them check the spider for sag.

[Caledon Ken]

Thanks.

You sound as though you have really good tech. I will have to see if I can find one.

One last question... lets say it does have to be reconed and JBL parts are not available. Is there any other vendors you would feel comfortable with using.

Thanks again for all the information. I didn't even know you could get a magnet re-charged.