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Dear Lew,
I posted a query in the midst of the Silvaweld thread, and it may have gotten buried.
i was asking about your Klyne, preamp, which you seem to have swapped out of your
second system. Do you have a further take on it yet? Did you try it with a low or medium
output moving coil cartridge? Finally, I'd be interested in hearing more about the Beveridges.
Thanks.
Follow Ups:
I'm a former Beveridge model 3 owner and now I own Martin Logan CLXs and I have a pair of older Monolith 2s.The Beveridge are really a unique speaker and there are some renown critics that still think they are the best sounding speaker ever made to this day..On some accounts,they may be correct.The model 3s at least,had one of the most brilliant executions I have ever witnessed.They were very accurate,they were a music system,not a speaker system that came at you.The music would fill the room and it would follow you everywhere and do it with great resolve.They had an acoustical lens which was much like a horn in a sense.The electrostatic panels were inside a compressed cabinet when all was said and done,and they would radiate out the front thru the acoustical lens at 180 degrees out of each speaker facing each other.
The woofers inside the cabinet that crossover at 200cps were gawd awful..It didn't matter tho as I was biamping into a stacked pair of Magnepan Tympani bass panels thru an ARC EC21 crossover.
Now,with all this illustrious chatter about how wonderful they are,you might ask,why did I sell them? The truth is,the panels just did not like the Michigan climate..I was tearing them down every two weeks and corona doping the panels..
I have also heard the 2SW2s and liked them very much but didn't find any.I would love to have another pair of Beveridge speakers but I have run out of room.I thought I should add,the element behind the design of the Beveridge was not to build speakers,but rather it was to build the perfect music system where you heard the music and forgot it was coming out of a pair of loudspeakers..I think Harold Beveridge was able to that better than anyone to this day AFAIC.
Honest amplification is better than 2nd order distortion anytime.
Edits: 03/01/14
Mike, Perhaps your Model 3s had the experimental panels that HB built for awhile on printed circuit boards (or something like that). Rick Beveridge talks about that on the current Bev website (if it's still up and running). HB was searching for a less tedious method of manufacture, and he started to experiment with the advent of the Model 3 speaker. But those panels were a complete disaster, according to RB, led to customer dissatisfaction with the Model 3. There's more to the story, but I forget the further details. HB abandoned the method for the reason you cite; the panels were very unreliable. In any case, my 2SWs seem to be running with their 6 original panels (3 per side vs 2 per side in the Model 3s) doing fine.
Apparently HB was not focused on the quality of his woofers. The outboard woofers originally supplied with the 2SW are also said to be crap. I've never seen or heard a pair, and I don't even know what they looked like. Anyway, I am "pleased as punch" with my TL woofers.
My 3's have the same panels as the model 2(SW)..I am essentially in the same climate as you with long dry winters and incredibly humid summers (when it even gets warm!).
I have talked the previous owner on this and he's never had a problem with the Beveridges in the 25 yrs he's had them & he's not experienced arcing of any sort. I've owned electrostatics of various manaufacture for 30 years and the only arcing I have experienced has been my own doing ,unfortunately.
I wonder if you had the more robust carbon cast stators or the FR4 (circuit board material) stators?- never the less interesting commentary.
Thanks
I think it's true that the experiment with the circuit board panels was short-lived. Shorter-lived than that of the Model 3. Hence there are certainly Model 3s with the standard panels. I was just struck by Mike's negative experience, and that is an explanation that came to mind.
The panels can't really arc in the sense that conventional ESL panels arc, because of their unusual modus operandi. There is no bias voltage on the diaphragm, in the conventional sense of that term. I think that contributes to the long life in no small way.
Lew
OMG,they did have about one inch of a circuit board coming out the bottom of the lower panel and knowing my luck,that probably was the experimental model.
I did make out well because the guy I got them from,wanted them back so he traded me a pair of Acoustat servo amps and a pair of Acoustat 4a.I only paid 1300 for the Bevs but not only that,I got all brand new panels free from Hafler,after he bought Acoustat.
Honest amplification is better than excessive 2nd order distortion anytime.
While there is no dc bias voltage on the metallized diaphragm the stators do have a dc bias voltage applied. We need a dc bias voltage somewhere to make the speakers work. The Beveridge uses a high resistance stator plate with dc bias voltage applied. AC signal as well on the stator plates.Arcing is always a possibility with any stat. Some designs are less prone to this problem than others.
Edits: 03/04/14
I know how they work. Perhaps I used the wrong term when I said no "bias voltage". What I meant was to refer to the unique way in which the Bev panels do work, where the diaphragm is conductive and there is no static charge on it. Thanks for correcting my semantics.
I thought it would nice for others that may not have as complete an understanding of the Beveridge. It is unique amongst stats.
In that connection, I have wondered how the Model 3s work off of a conventional amplifier but using the unconventional Bev ESL panels. Do they have a power supply built in, to bias the stators, or some equivalent?
Good question. While I have seen and heard the Model 3 I have never taken apart the Model 3 just the Model 2. The patent, etc., discuss the Model 2.
There must be some sort of bias power supply to energize the plates. Since both the plates and diaphragm are driven actively I am assuming two separate step-up transformers.
Rick restored my Model 3's. They had original transducers. Now, with new mylar.
Vbr,
Sam
Sam
Was it real expensive to have your panels restored? I would love another pair of model 3s. Another point I was wanted to mention is,you didn't really have any placement issues with the model 3s either.It is probably the most brilliantly designed speaker to this day on many accounts.
Honest amplification is better than excessive 2nd order distortion anytime.
Hi Michael,
I had the loudspeakers renovated. Rick did the panels and outer skin with a friend of his in Chicago(?) sorting the electronics. The Beveridge loudspeakers, I have the Model II and Model III, image so well in any number of places, as you have alluded.
Here's a link to the Model III's:
http://cgim.audiogon.com/i/vs/i/f/1258338370.jpg
Vbr,
Sam
Interesting comments on the grid stop resistors. On the Futterman amp I have ferrite beads have been installed on the connections to the tube sockets to deal with such potential oscillations. Something to perhaps experiment with.
I don't have the Beveridge Model 2s ( wish I did) and I don't have a Klyne full function preamp but I do have the Beveridge Model 3's and owned a Klyne 7 series phono pre for many years. In addition to that, I own the Aesthetix Io Signature with 2 power supplies and stepped volume controls from Benz, Lyra and Platinum series Koetsu cartridges.
The Klyne was run through the line function of the Io ( it has one line input) shined in naturalness and cleanliness for a solid state Phono. I could of lived with it forever. The Io's sense of density and dynamics was too much to give up on. The Io is holographic and big.. the Klyne was almost polite in comparison. The best solid state Phono I have heard.. yet. I have not played alot in the SS arena.
I still find the Io competitive with most of the big stuff that I have heard. The Janus quite frankly while, very good ,I felt, did not measure up.
The Model 3's characteristic that still make me excited are of course the presentation of the image ......and the dynamics , not loudness , but the movement from soft to loud and how well and striking that can be.
I am relatively new to the Bev's but have owned Acoustats, all types of Quads (still do)... I have never had Soundlabs but have had a brief opportunity to listen in show conditions. They are impressive speakers.
AJ
Good idea. Bill Thalmann actually did that already on my Bev amps. There are four resistors that link the solid state input stage to the tube output stage. Two 1K resistors go respectively to the grids of two of the 4 output tubes (grid-stoppers). The other two are 7.5M and go to the cathodes, I think, of the bottom tubes in the totem pole arrangement. Bill put ferrite beads on the afferent leads (where the resistor leads solder to the input board and before the body of the resistors) of all 4 resistors, early on, in our attempt to quell oscillation. It definitely helped. Then I installed a shield made with TI Shield (Texas Instruments), between the input/driver board and the output stage board, in each amplifier. I really think that what may have happened with the one amp that is giving trouble is that I installed four new output tubes in that amp, which probably brings up the transconductance and enhances the tendency to oscillate. So, something more is now needed. Like I said, the other amp, still on its original tubes, does not oscillate and sounds excellent. The other thing I did that probably does not help was to bypass a 10uF electrolytic that is used as a coupling cap with a 0.1 uF teflon film cap. Possibly the electrolytic was deliberately chosen to limit bandwidth and reduce the tendency to oscillate, until I "tweaked" the circuit and thereby created problems of wide bandwidth. But as a true audiophool, I could not tolerate an electrolytic coupling cap.
I know the characteristics of new tubes can cause issue in circuits where old ones existed.
I doubt the 10uf cap was chosen deliberately as a bandwidth limiting etc part. You could try a Solen 10uf in that position it has to be way better than the electrolytic.
If you want to try one, I have a couple that I can send you for the experitment.
This kind of spurious oscillation requires a good scope and injection of signal with lots of time to try grid stoppers, ferite beads and different values for bandwidth.. etc.
Time and frustration like chasing hum and radio frequency noise.
AJ
Thank you for the kind offer, but I've got a surfeit of suitable 10uF film caps I could use. For now, I might try a bipolar lytic in place of the polar one, was going to do that anyway. Don't want to introduce another variable by going to film. I don't know enough about this problem to argue one way or the other, but some knowledgeable guy on TubeDIY did think that the electrolytic was at least in part chosen for its limited bandwidth. Even if that is correct, I've got the 0.1uF teflon bypassing the lytic, so bandwidth is restored, for better or worse.
The maddening thing about trying to cure this problem in Bevs is that you can only model it based on behavior when the amp is connected to the speaker. When the amp is on the bench, disconnected from the speaker, Bill found it to be even more prone to oscillate, if anything. So you have to try a strategy with the whole assembly, using real music input. Then take it apart again to try something else. But keep in mind, I am having the problem ONLY when I play SACDs and ONLY on one channel.
I was liking the Klyne very much, in the Beveridge system, but then I came into possession of an Aesthetix Janus, via the estate of a close friend. Because the Janus has balanced inputs (and outputs) that could accommodate the balanced outputs of the Ayre cdp, and because of natural curiosity, I inserted it into the system in place of the Klyne. I must say also that since then I have found the remote control of the Janus to be rather addictive.So, at this point, I have heard the vintage Quicksilver full-function preamp, the updated Klyne 6LX/P, and the Janus, all driving the Beveridge speakers and using the same sources. First of all, the Beveridges easily reveal differences among the 3 preamps. So far, I have only used one MM cartridge for analog, the Grace Ruby. My take is that the Klyne phono section may be superior to that of the Janus in most ways, especially in terms of very clean low bass. The only respect in which the Klyne falls down a bit is in terms of the sense of depth and "imaging"; with the Klyne, sometimes images seemed to hang on the speakers, instead of creating a holographic sensation in between the two Bev speakers. Both the Janus and the Klyne linestages outshine the Quicksilver linestage, IMO, but that may be because I rolled capacitors in the Q that have not had a chance to break in. The Q phono stage, with my few tweaks, is also possibly preferable to that of the Janus. All of which leads me to believe that the Janus may need new tubes in phono. The Janus linestage is superb, regardless. My sense of dissatisfaction with the Janus phono led me to try my Silvaweld MM phono stage into the Janus high level section. This combo is dynamite, what I am listening to now. I must say I did a good job messing with the Silvaweld as much as I did. I intend to go back to the Klyne at some point to dial in my thoughts better. I never dreamed I would be "inheriting" a Janus preamp when I earlier purchased the Klyne. Under the circumstances, I would much rather have my friend back.
As to the Beveridge 2SWs: They are very finicky; you have to keep at them to get the most out of them. Partly this is because of their age and partly it is the built-in complexity. That said, I love them. I know that does not tell you much. The totality of the system that I "love" includes my home-made TL woofer cabinets that house a pair of KEF B139 woofers. I built those more than 30 years ago. Driving the KEFs is a used Threshold amplifier, below 100Hz via a Dahlquist DQLP1 crossover. I cannot hear any discontinuity at the crossover point. Nor can anyone else. I guess the 845PXs give a bigger more spectacular sound but tonal balance is perhaps better with the Bevs, possibly also inner detail is more evident but maybe not. Bevs seem a tiny bit more extended in the treble. The Bevs also benefit from being in my basement. I am finding that concrete flooring is a real good basis for vinyl. Too bad the Sound Labs would never fit through the stairway to my basement.
Edits: 02/25/14
Thanks very much for your articulate and revealing post. I've always been intrigued by
the Beveridge speakers, having seen them once in a store long ago that was too high-end
for me to dare to ask for a demonstration. I had heard that they are complex and finicky.
Keep us posted, especially if you try a moving coil cartridge with your setup.
Main issue with Bev speakers is oscillation of the direct-drive amplifiers. They seem to be very prone to do that. You can have them dialed in with used tubes. Then if you replace the tubes with new ones, that naturally will have a higher transconductance, there are more problems with oscillation. Between Bill Thalmann and me, we recently came to the realization that the 1K grid-stop resistors used on the power tubes are actually not "correctly" installed for optimal prevention of oscillation; the leads are too long on the side of the resistor nearest to the grid. I am next going to replace the 1K grid-stops with 2.2K Rikens that I have here, and I will take that opportunity to mount them right "on" the grid pins of the tube socket, close as possible. I have hopes that this will help for the one amplifier (with new tubes) that is thrown into oscillation when fed from an SACD source. (I also learned from Bill that SACD players put out quite a lot of very very high frequency spurious noise.) The other amplifier, still with its old original tubes, has no issues with SACD.
Beyond that stuff, other Bev owners tell me that they have had issues with blown power transformers (probably due to old leaky electrolytics or blown rectifiers) and with getting the ESL panels rebuilt. I bought some extra alu-coated mylar from RM Labs, just in case that is ever needed. It's cheap insurance.
On the other hand, considering the age of any Beveridge speaker, they are remarkably long-lived. One could only wish that the Sound Lab speakers would be as durable, actually.
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