Beveridge Model 5 - Restore

[Audio Fan]

Edit: I originally had the title of the thread as Model 3, but after determining they are Model 5, I asked the Admin to change it. Since starting this thread, it has turned into more of a Beveridge speaker history thread than just a Model 5 restore discussion (starting around page 7). All of the various models, the Model 2, 2SW, 3, 5 and 6 are discussed in the following pages as well as first person details about the companies Harold Beveridge owned over the years making the different models.

Thread update: I now have a Model 3 restore thread here: http://www.audiokarma.org/forums/showthread.php?p=5838939#post5838939

Back many months ago, I picked up some gear from a former (I think) Aker and while we were talking, he showed me a set of Beveridge speakers sitting idle in the corner of his garage. He didn't really seem ready to discuss parting with them, so I didn't press the conversation too much.

Well, fast forward to this month. I circled back with him and asked if he had ever done anything with them. He said no, he still did not have time and asked if I was interested. I said absolutely. Naturally, the first question was, do they still work? He agreed to hook them up and give them a try. Sadly, in his last move, several of the binding posts were snapped off, so it took a little time to get them hooked up. Upon getting them hooked up, it became apparent that there is an issue with them and that is where this thread begins.

The down firing woofer plays fine, but the stat only gets the most faint of sound coming through it, so that "seems" to indicate an issue with the crossover (I hope). Also, the woofer seems to have a lot more of the signal than it should, so I'm thinking the stat is just not getting much of a signal at all.

Frank, the previous owner and being a really nice guy, made it a deal I could not refuse. For the opportunity to get them up and running and having a speaker of this quality, the price was just way too good to turn down.

So here they are, just gotten them home and stood them up in the garage. They are physically in very good shape, a slight ding here and there, but nothing major that cannot be touched up easily. I actually thought they were a little larger. The footprint and height are really not much bigger than my Maggie MG-1's.

 

[audiomagnate]

It's probably not the crossover but the energizing circuit that's bad. The panels aren't getting any bias voltage. Is it both speakers that have the problem or just one? If it's both I'd be surprised if it's not a hookup or power problem. I'm sure you checked all the fuses. I've alway wanted to hear a non-dipole electrostat. I've heard the big originals, very nice. Beveridge was a two man operation back in the day, Beveridge and the 19 year old kid that built everything.

 

[eurasian]

I think what you have there is a set of Model 5s, not Model 3s. IIRC, the 3s had 2 3' electrostatic panels for a total height of a bit over 6' and woofers top and bottom, while the 5s used a single 3' panel and lens with a woofer in the base section only. The transducers themselves were of different design, with the 3s using the original style cast epoxy stators and the 5s using the "circuit board" type. You should be able to use a flashlight to peer through the center of the lens and see them.

Whatever you have, I hope you can get them going again as the Beveridges I have heard over the years were truly magical performers in many ways. If it hadn't been for transducer reliability and fan noise issues, I would have kept my late production pair of Original Model 2s.

 

[audiomagnate]

They're still around. It's run by the founder's son, who's keeping things going. It looks like you can get help restoring these straight from the source. http://www.bevaudio.com/ I don't see your speaker there however.

 

[audiomagnate]

I think what you have there is a set of Model 5s, not Model 3s. IIRC, the 3s had 2 3' electrostatic panels for a total height of a bit over 6' and woofers top and bottom, while the 5s used a single 3' panel and lens with a woofer in the base section only. The transducers themselves were of different design, with the 3s using the original style cast epoxy stators and the 5s using the "circuit board" type. You should be able to use a flashlight to peer through the center of the lens and see them.

Whatever you have, I hope you can get them going again as the Beveridges I have heard over the years were truly magical performers in many ways. If it hadn't been for transducer reliability and fan noise issues, I would have kept my late production pair of Original Model 2s.

They sound like 3s to me:"The Model 3 was my father's attempt at cutting the cost of production. The two-foot diameter cylindrical cabinets were intended to be much less expensive to build. It was also hoped that, by building three foot long transducers and lenses, we could seriously reduce the production costs. Eliminating a built-in amplifier also reduced costs and increased our customer base.

Unfortunately, it turned out that the costs did not actually go down. The increased transducer length meant that everything in the tooling had to be that much bigger. With the increased difficulty in handling, it actually took about twice as much labor to build a three-foot transducer as a two-foot one. The same was true of the lenses."

==============

You have a real slice of history there, treat them kindly and let us know how it goes.

 

[Audio Fan]

I think what you have there is a set of Model 5s, not Model 3s. IIRC, the 3s had 2 3' electrostatic panels for a total height of a bit over 6' and woofers top and bottom, while the 5s used a single 3' panel and lens with a woofer in the base section only. The transducers themselves were of different design, with the 3s using the original style cast epoxy stators and the 5s using the "circuit board" type. You should be able to use a flashlight to peer through the center of the lens and see them.

Whatever you have, I hope you can get them going again as the Beveridges I have heard over the years were truly magical performers in many ways. If it hadn't been for transducer reliability and fan noise issues, I would have kept my late production pair of Original Model 2s.

Yes indeed, it seems based on that description, these are the Model 5 series then as they are about 5' tall which is smaller than the Model 3's. There are absolutely no labels anywhere that can be found, so hard to really know what I have here. The first time I saw them, they were tucked in a corner next to an armoire with a box on top of them, so I could really only see the back of one. Today was the first time I actually saw them first hand and brought them home and the previous owner also thought they were the Model 3. OK, not sure if that is a good or bad thing yet.

There is a single woofer in the bottom and the chamber is about a foot and a half before the stat on the topside which does indeed seem to be about 3' in length.

 

[eurasian]

Here is a link to a thread about another pair of 5's undergoing restoration. There is a schematic in there which might help you with your set:http://www.audioasylum.com/forums/MUG/messages/16/168693.html

Best wishes and good luck with your Bevs

 

[Audio Fan]

Alright, at this point, not really sure where to go with the troubleshooting. I felt more confident they could be repaired if they were Model 3's, but given these are Model 5's and use a different type of stat, from what I have read since last night, they are prone to issues over time.

The current story is that they both blew fuses one evening. The previous owner then set them aside as he was not sure if it was the amp or the speakers. Following that, he moved, I think, and they just sat in his garage.

Since Beveridge speakers of any kind are so rare and little information is available, I thought I would go somewhat overboard on posting some pictures for everyone to see. If anyone has any guidance/input, please feel free to add to the conversation.

 

[Audio Fan]

Next group of pics.

 

[Audio Fan]

Crossover

 

[eurasian]

The circuit board is the voltage multiplier that keeps + and - charges on the stators, probably in the 3-5kV range, and there should be a few capacitors on the underside. The big transformer is the audio step-up, and might be capable of delivering enough amperage to hurt you if you aren't careful -- these are usually wound 50:1 and up, so they can be lethal if you are testing them with a high level music signal. Don't know what might be under the crossover board, but several of the varnished wires seem to disappear through it. The three bananas connect to the transducer which is, I believe, unique to Beveridge in that the diaphragm is aluminized mylar and carries the audio signal while the stators are constant charge. This is the opposite of how every other esl manufacturer that I am familiar with does it.

I can see why these were so expensive and could have been money losers for Beveridge -- no mass production here.

Good luck with them.

 

[elcoholic]

I talked to the son (David?) a couple of years ago. He was just moving into a retirement home as the manager. He fell on hard times and was locked out of his shop in Santa Barbara by the LL. Unable to pay the back rent, he lost everything. What a shame. He's a really nice guy and invited me to come by and shoot the shit. I think he'd be willing to help you anyway he could. Good luck. I really hope you get them healthy, they are truly special.

 

[Audio Fan]

The circuit board is the voltage multiplier that keeps + and - charges on the stators, probably in the 3-5kV range, and there should be a few capacitors on the underside. The big transformer is the audio step-up, and might be capable of delivering enough amperage to hurt you if you aren't careful -- these are usually wound 50:1 and up, so they can be lethal if you are testing them with a high level music signal. Don't know what might be under the crossover board, but several of the varnished wires seem to disappear through it. The three bananas connect to the transducer which is, I believe, unique to Beveridge in that the diaphragm is aluminized mylar and carries the audio signal while the stators are constant charge. This is the opposite of how every other esl manufacturer that I am familiar with does it.

I can see why these were so expensive and could have been money losers for Beveridge -- no mass production here.

Good luck with them.

Thanks so much for the overview, I am a complete novice, so any and all information is helpful. I am aware of the potential dangers here also, so I will be using extreme caution if I decide to start doing real testing.

I'm not in any big hurry, so I'll take out the crossover next and photograph it for further updates here.

 

[Audio Fan]

I talked to the son (David?) a couple of years ago. He was just moving into a retirement home as the manager. He fell on hard times and was locked out of his shop in Santa Barbara by the LL. Unable to pay the back rent, he lost everything. What a shame. He's a really nice guy and invited me to come by and shoot the shit. I think he'd be willing to help you anyway he could. Good luck. I really hope you get them healthy, they are truly special.

Actually, I have been talking with MeatInStereo who has a set of Model 3's. He has probably had the most recent communications with Rick (Harold's son), so he may be able to reach out to him for some advice (hopefully). I've also reached out to the other Model 5 owner on the Planar Asylum site, so maybe we can start pooling our resources a bit and see if there is a logical direction to consider.

 

[elcoholic]

It would be so cool to get them going again.

 

[Audio Fan]

I didn't have too much time this evening, but I did get a chance to take out the crossover for a closer view. Some pics.

Next, on to the stat for some measurements.

 

[saltwater]

Those are really interesting. I would put money on the stats not working correctly. Crossover looks good. Nothings charred, burnt, or buldging. I would also take some time and see if the stats are receiving any irregular voltages.

Keep us posted, those are neat speakers. Sorry Im of no help in knowing anything about them.

 

[Audio Fan]

Those are really interesting. I would put money on the stats not working correctly. Crossover looks good. Nothings charred, burnt, or buldging. I would also take some time and see if the stats are receiving any irregular voltages.

Keep us posted, those are neat speakers. Sorry Im of no help in knowing anything about them.

I agree with you that it is probably the stats, the history for the Model 5 shows issues over time. The only thing that gives me hope is that they started having issues at the same time, so that is a little suspect since the known issues happened slowly over a period of years.

As well, these are the early version of the Model 5, later versions had the crossover below the woofer (which was much easier to get to!). This set was manufactured in 1980 and Model 5's were made at least through 1987, so I'm also hoping that maybe the early ones were a little more robust.

Keep our collective fingers crossed! :yes:

 

[Audio Fan]

Next up, the stat and acoustic lens sections.

This was one of the very first Model 5's and from what I can see, the stat is not made from the circuit board material described by Rick and from a pic I have seen of another Model 5 made in 1987. It is quite robust. I'm hoping this means it may be repairable.

 

[audiomagnate]

You do not mess around. These things fell into the right hands, no matter what the outcome. True audiokarma.