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“ AR-LST, after Forty Six Years of Use”


frankmarsi

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4-27-18

Reaching out to members who know about this speaker.
I’m planning on replacing all of the capacitors in my LST speakers as I feel they’re long over due.
I’ve read about an AR change of one capacitor value here:  http://www.classicspeakerpages.net/IP.Board/index.php?/topic/4198-roy-allison-ar-3a-ar-lst-mark-levinson-cello-amati-speakers/&page=2


According to the post from a very dearly missed member “Minh Luong” (I wonder where he is these days?), apparently AR had cited a change of one of the ‘caps’ that was decided later on when the speaker was already in the field.

At the same time, I also plan on changing all of the original tweeters and substituting them with used but operating AR-9 tweeters as in the last couple of years I have purchased 20 of the AR-9 tweeters used. This work will require 16 tweeters. I could replace the front two only as some folks recommend however, as long as I’m at it I may as well install all four per cabinet.
In addition, I would need to know what type of ‘cap’ I should use, whether polarized or not, the brand name, build type, etc.

The reason that has moved me to finally do this procedure is that I noticed a slight ‘thump’ sound every once in a while emanating from one woofer, the other three woofers are not making this noise. At first I suspected it may have been one of the double amplifiers I’m using but, as time has passed I’m feeling it may actually be a  X-over capacitor that’s to blame. I’ve learned in the past, that when a large amplifier ‘cap’ goes, it’ll go in a furious display of abrupt and horrific noises.

SInce I’ve used these four LSTs steadily since 1989 with a slight non-use period between 1994 to 1998 when they sat idle, it may be high time. Though, since 1998 to the present they have been used regularly and enjoyed practically everyday.
While I’m at it, the chance to replace the ‘caps’ in my third set of LST’s might as well be done at the same time.
Any advise, methods and prior experience would be greatly appreciated.

FM

Further reading:

http://www.audiocircle.com/index.php?topic=137644.0

https://www.vinylengine.com/turntable_forum/viewtopic.php?f=85&t=42191&start=30

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/3853-bypass-caps-on-ar-lst/


P.S. for the inquisitive, I have no intentions of tri-amping, or removing the transformer.
Also, both amplifiers were completely rebuilt by an industry premier rebuilder in 2009.

 

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Do not use polarized capacitors.  Audio crossovers require NPE (non-polarized electrolytic) capacitors.  Replace like-for-like, as far as actual capacitance is concerned.  Voltage can be the same or higher. 

If using NPE (which is what I believe was used originally), I like Bennic NPE's, available at Madisound.  I've also used the Mundorf brand of NPE's.  They're called E-Cap's.  There's 2 types of E-Caps, Plain and Raw.  Plain has a loss factor of 0.05%, while Raw has a 0.08% loss factor.  The Mundorf E-Cap's are available at Sonic Craft and Parts Connexion.

Of course, polypropylene capacitors can also be used.  But, they're trickier to use, and in deciding which brand to use?  Also, cheap or boutique?  Plus, should you take the difference in ESR between NPE's and poly caps into account?  And if so, should you add a series resistor to compensate for said difference?  Lot's to consider.  Though, if you want to keep the original sonic signature, it's best to stick with NPE's.  If you want to 'improve' the sonic signature, that's when you need to decide between NPE or poly?

Good luck.  It sounds like an interesting project!  And pictures please, once updated!

Oh yea, Erse Audio makes their own NPE, mylar, and polypropylene capacitors.  You can order those directly from their factory.

 

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My 9's have tweeters from some AR 91's. I was under the impression that they are one in the same, part # 200029-1. By using the AR9 tweeters in the LST they would most likely have more output and power handling ability, but wouldn't there have to be some modification of the crossover?  What about having the original tweeters rebuilt by Chris-1. That could be a viable option.

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Thanks Stimpy, I’ll have to consider all of your suggestions and will definitely capture each step in fotos.

DavidR, good question.

I don’t have the info in front of me this moment but, I believe their X-over point is the same as the 3a is for the drivers.  In terms of their resonance, I don’t know that spec.

Larrybody, the replacement tweeters have the same S/N of # 200029-1.  Having my originals rebuilt is likely out of the question as I have made the expenditure for the AR-9 tweeters already. And if like you said, the newer tweeters will handle more power which I trust they will then, I'd rather take that route of course.

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I have some experience with several brands of polypropylene capacitors, in that I've tried several brands, when recapping various AR speakers.  Specifically, I used Dayton 5% poly caps, on my AR-1MS speakers.  On my AR58S speakers, I used ClarityCap CSA's on the tweeters, and ESA's on the dome mids.  Bennic NPE's on the shunts.  Finally, on my AR90's, I used a combination of Mundorf EVO Oil and Mundorf Supreme capacitors for the series values.  Axon True Caps were used for the shunts.

As to sound quality, after the recap's, the Dayton's were very balanced.  Very even in response.  Good sound stage depth too.  But, they were just a little sibilant too.  An "Esss" emphasis on some music.

The ClarityCaps were warm and musical sounding.  Smooth.  Easy to listen to.  A sound stage wider than deeper.  Unfortunately for me, a bit closed in and muted.  Especially in the upper mids.  There was a suck out on voices, that made vocals hard to hear.  The Clarity's seemed less efficient as well.  The preamp volume needed to be increased, to match the volume of the stock speakers.

Now for me, the best for last.  The Mundorf recap was awesome.  Clean, clear, and detailed.  Less haze and distortion.  A proverbial "clearer window" on the music.  As a test, to prove what I was hearing with the Mundorf's, I compared a recapped 90 to a stock speaker.  No contest.  The recap was night-and-day better.  I even hooked up a single UMR dome, to a recapped crossover, and it produced better mids and highs, than the whole stock speaker.  And the stock speaker had both the mid dome and tweeter playing!  My son commented that the new caps were cleaner, and that the old crossover sounded distorted, and had a static type of distortion.  After hearing the Mundorf's, I now want to recap the 58S speakers again, with Mundorf's.

 

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This sounds like a terrific project, Frank - please take many photos along the way!

To the best of my knowledge, the tweeter is identical in the AR-9/90/91, but one difference in the AR-9 tweeter is that it doesn't have the dispersion characteristics of the AR-LST/3a model - it tends to be more directional in nature. I also think that Larry is correct that this tweeter will have more output than the original LST tweeter.

Stimpy's suggestion of Mundorf caps sounds like a winner, especially with a superb speaker like the AR-LST.

 

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ar_pro, I’m banking on the fact that the LST has those three faces of radiation so the limited radiation of each AR-9 tweeter may be compensated for in that regard?

The Mundorf caps don’t seem to be overly expensive and that brings me to the next question; if a more costly capacitors would make a difference in what I ultimately hear?

Next, I’ll have to find out the actual values of the necessary caps.

I’ll probably use silicone to keep the caps stable or seek out the clips I’ve seen in use, perhaps a combination of both. I don’t recall the gauge of the enclosure’s X-over wiring if it was 16 or 18 gauge.

What is eating at me is the fact that I’ll have to be without any music once the X-over ‘resto’ begins. Granted, I have the actual AR-9 set-up in the other room but, the LST’s are the closest speakers to me and since I’m in the process of auditioning a couple of tonearms lately through them, this is a set-back.

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If this was just an LST re-cap project, I would suggest to find and review a thread originated by KlausDK, which went through some fairly rigorous analysis and at least one revision before settling on his preferred outcome. His knowledge of AR speakers is huge, and his writing and his handiwork are excellent.

This may be off-base, but I suspect this may become more of a "mod" project with the proposed change of tweeter components, which might require a bit more expertise to be able to pull off this revision. This assumption is simply based on a quick look at specs and schematics, so please challenge or correct any misstatements made here. From looking at product data sheets, it appears that the LST efficiency is measured at 89 dB while the AR-9 is 87 dB. In the tweeter circuit, the LST has only a 6uF cap, but the tweeter in the AR-9 has both a 6uF and a 4uF cap as well as a 0.105 coil. And lastly, the LST crosses over at 5000Hz while the AR-9 crosses at 7000Hz , so you'll want to be certain that somehow you've got this 5K to 7K range covered if the newer tweeters are replacing the originals.

On the LST schematic I have, the 150uF woofer cap is the same as in the AR-3a, but it also shows a 40uF cap for the midrange instead of the 50uF found in the 3a, so you should double and triple-check all of this before placing any parts order. Get the screwdriver out, remove a woofer, and take a look under the hood. Also, this schematic shows a large 5000uF combo cap which appears to be associated with the transformer (?) - - not sure if this one ever requires replacement.

Others will offer thoughts on this idea of replacing the original tweeters with newer fluid tweeters. 

Edit: just to clarify, the OP's proposal is to replace the original tweeters from a three-way system (LST) with non-original tweeters meant for a four-way speaker system (AR-9), and it's uncertain if there is any way possible for these replacement tweeters to reach down to 5KHz to meet the upper end of the LST midrange drivers. 

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23 minutes ago, ra.ra said:

 And lastly, the LST crosses over at 5000Hz while the AR-9 crosses at 7000Hz , so you'll want to be certain that somehow you've got this 5K to 7K range covered if the newer tweeters are replacing the originals.

This is an excellent point.

The 3-way AR-91 crossover is at 7500 Hz.

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3 hours ago, Stimpy said:

The ClarityCaps were warm and musical sounding.  Smooth.  Easy to listen to.  A sound stage wider than deeper.  Unfortunately for me, a bit closed in and muted.  Especially in the upper mids.  There was a suck out on voices, that made vocals hard to hear.  The Clarity's seemed less efficient as well.  The preamp volume needed to be increased, to match the volume of the stock speakers.

Something is wrong here. I have the same caps in my AR91 and I do not experience this at all.

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10 hours ago, Stimpy said:

As to sound quality, after the recap's, the Dayton's were very balanced.  Very even in response.  Good sound stage depth too.  But, they were just a little sibilant too.  An "Esss" emphasis on some music.

I was planning on using some Dayton 1% precision caps in my 9's.  I have read that the inclusion of some .01 film and foil bypass caps may take care of this sibilance problem. Did you use any type of bypass cap in those 58S's?  Also looking for some 58S cabinets to put these AR 91 parts in. 

T1fTjpjl.jpg 

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10 hours ago, frankmarsi said:

I’d like the AR-LST speakers to sound exactly as they do now, no added warmth, no nothing except if those AR-9 tweeters add a touch more of the highs which I believe they will that would be fine as long as it’s not exaggerated and unnatural.

 

This sounds like a fun project.  You seem to have some specific goals in mind.  This is great since it is hard to plan a route or get directions if you don't know your final destination.

Having two pairs of speakers puts you in a unique position to fully evaluate the effects of the modifications.  Do you have the ability to do A/B testing?  If not, you may want to establish a methodology before you start.  I suggest that you A/B the speakers before you make any modifications to establish a baseline.  You are in great shape if the speakers start out sounding the same.  You could then make one modification at a time and then evaluate the change (or no change) in the sound.  You have lots of options on how to proceed.  You could modify the speakers in pairs or one at a time.  You could evaluate each change cumulatively against the baseline or evaluate the changes in a leapfrog fashion.  Having a plan in place on how to proceed should increase your odds of meeting your goals.  I'm mentioning this since you seem to be pretty happy with your starting point.  I'd hate to hear that you strayed too far away from it and couldn't get back.

Do you have capacitance/ESR meter?  If not, you might want to purchase one so you can better understand the changes that you are making.  For example, if you like the way a particular crossover sounds with aged or "well broken-in caps" you may want to try replacements with the actual aged values versus the original values.  You might want to do something like this if you wanted to retain the overall voicing, but improve the imaging by having the left/right pairs better matched (assuming that the caps left/right aged to different values).

I wish you the best of luck with this project and am looking forward to reading about the progress.

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9 hours ago, DavidR said:

Something is wrong here. I have the same caps in my AR91 and I do not experience this at all.

I can't explain why I heard what I did, through my AR58S speakers, and you didn't, with your AR91's?  It is what it is, I suppose?  But, what I described was very pronounced and obvious to me.  Too many years working in audio, and in audio mastering, for me to ignore what I was hearing, I suppose?  I eventually added a Dayton Film & Foil 0.1uF bypass cap, to the ESA cap.  That helped improve it's upper midrange response.  It wasn't 100% successful, but it helped.

One difference that I can think of, between our recaps, I used Bennic NPE's as shunts, except where Madisound didn't stock a 8.0uF Bennic NPE.  So, I used 8.0uF Carli MET mylar cap.  Did that do something weird?  It shouldn't have, but I do plan on experimenting to find out. 

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1 hour ago, larrybody said:

I was planning on using some Dayton 1% precision caps in my 9's.  I have read that the inclusion of some .01 film and foil bypass caps may take care of this sibilance problem. Did you use any type of bypass cap in those 58S's?  Also looking for some 58S cabinets to put these AR 91 parts in. 

T1fTjpjl.jpg 

That's a nice problem to have!  I'd like to have a spare set of AR91 drivers lying around.  Good luck with the project. 

As to my AR-1MS and AR58S recaps, I did add in bypass capacitors to both sets of speakers.  I always use the Dayton Film & Foil bypass caps.  With the AR-1MS, they smoothed out the sibilance, and on the 58S issues, they smoothed out the upper mids as well.  So,I pretty much add in bypass caps to all of my recaps, now.

As to your AR9 recap, using the Dayton 1% polypropylene caps, they should be fine.  The 1% caps received a much better review at the Humble Home Made HiFi site.  But, I do need to state, I've never tried the Dayton 1% caps.  I don't want to mislead you.  The 5% caps that I tried, with bypass caps were fine.  No reason to think the 1% caps would be worse.

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4-28-18  10:37 A.M.

 

Glitch, ar_pro,  larrybody,  ra.ra., DavidR, and Stimpy, great advice from one and all!

With this wealth of information, I may have to sit back and reconsider my typical thrust towards instant gratification and make a plan as it is seeming to demand.

I hadn’t thought it would be this involved as the main thing I was thinking about was as follows, original capacitor values, wiring gauge, how the newly installed tweeters would sound (somewhat fearful they may be over-powering to what I’m used to all these years), and the actual moving around of these unwieldy, awkward and cumbersome manipulation in just placing them in a correct position to work on. Then, an important consideration is the hundreds of records which haven't found a shelf or home yet, they're in the way as they sit.

I’d probably work on them right in the room in which they presently sit and that’s the living room.

It’ll mean moving some furniture, a heavy marble table, stacked records, stacks of various parts in boxes, and clean-up.

I mention clean-up because I’ll also have to do some slight cutting of each cabinet in order to mount the replacement tweeters as they have rear connectors and I’ll have to either run wires through the cabinets by drilling a small hole for the front connectors or drill a tiny hole through the tweeters to facilitate the wires coming out to meet the front connectors. And this is for four main-system speakers. I must devise a plan of how to not let any saw-dust from making these cuts not remain in the cabinets and finding their way obstructing the woofer surround.

I’m thinking about the other two spare LST’s that have original tweeters but, as long as I’m setting-up a ‘shop’ atmosphere in my living room perhaps, I should work on them at the same time and replace their tweeters with AB-tech ones or the Hi—Vi tweeters I have on hand.

I’ll be using the 16 AR-9 tweeters in the main speakers as I feel they should be ‘All-AR’.

Come to think of it, it may be better to wait on redoing the spares in order to evaluate the results on the main cabinets as per Glitch’s advice.

I may have put myself in a situation that’s not compared to actually sitting and enjoying music, it’ll be like I’m in the original Mass. AR construction shop when these speakers were actually first built.  And although I jest, the more I ponder this somewhat of an upheaval to my casual life, I think this might be a job for ‘Super-Man’?

But, getting back to the task at hand; I‘ll have to construct, adopt or find a suitable small table or working area to place these monoliths upon for the actual work, use a vacuum cleaner, I’ll use my ‘Dremel” tool to cut a ‘V’ to clear the connector tabs on the tweeters so they’ll sit correctly in the original holes because these are some of the early model LST’s and have a completely round hole and therefore will not allow the newer tweeters to simply ‘drop-in’.

I’ll have to do two speakers at a time because they are ‘stacked’ and in terms of putting them back as they presently sit, it’ll make sense to do one stereo side at a time.

Then, I think that since my enjoyment in using these speakers is so important to me in keeping music in my life, I better do some soul searching and a tightening of the mental-belt to prepare myself for the task at hand. I must also consider my stupidly unpredictable ‘bad-back’ cause if I throw the old back out, I’m finished for what could be days and with no music, I’d be rather out of my comfort-zone and irritable.

If there are any other suggestions or tried and true methods, I’d like to read of them in these pages. In the mean time, I’m going to see if there is any more mental discipline left in the ole cranial cavity by doing some necessary yard-work. Being retired, I felt I’d be on easy-street but, the dull moments never seem to remain because there’s always something at hand to do and it’s always something I rather not be doing.

P.S. @ Stimpy, I already bought the 'caps' for the AR-9 when I purchased these speakers a couple of years ago in preparation, I just never got to it. It was $89. for both sides. Those monoliths will be last on the list of 'to-dos'.

FM

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1 hour ago, Stimpy said:

I can't explain why I heard what I did, through my AR58S speakers, and you didn't, with your AR91's?  It is what it is, I suppose?  But, what I described was very pronounced and obvious to me.  Too many years working in audio, and in audio mastering, for me to ignore what I was hearing, I suppose?  I eventually added a Dayton Film & Foil 0.1uF bypass cap, to the ESA cap.  That helped improve it's upper midrange response.  It wasn't 100% successful, but it helped.

One difference that I can think of, between our recaps, I used Bennic NPE's as shunts, except where Madisound didn't stock a 8.0uF Bennic NPE.  So, I used 8.0uF Carli MET mylar cap.  Did that do something weird?  It shouldn't have, but I do plan on experimenting to find out. 

I don't doubt what you hear (or aren't). I will add that my mid no longer 'stands out' but blends very nicely with the other drivers - very cohesive now.

It was the pre amp volume thing that has me wondering. I don't believe it is the shunt caps. It might be defective, in some way, 25uF ESA caps. Cold or cracked solder joints. If you want to send them to me for testing let me know.

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Just a thought, but how about keeping one pair of LST's in their present condition, while working on the other set? Simultaneously restoring four of these speakers, especially under less-than-perfect conditions is asking a lot.

And if I could make one suggestion, it would be to find as dedicated a work space as possible - basement, garage, spare room, etc. - some place that will allow both room to work, store your tools & parts, and provide a stable platform for these heavy speakers. 

 

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13 hours ago, larrybody said:

My 9's have tweeters from some AR 91's. I was under the impression that they are one in the same, part # 200029-1.

This is correct, Larry, and is explicitly stated in Tim Holl's paper on the 9 series. Aside from the woofer size, only the midrange drivers in these models displayed differences, and that only concerned the amount of ferrofluid. 

13 hours ago, Stimpy said:

The Clarity's seemed less efficient as well. 

I don't even know what this means - - how does one gauge a capacitor's efficiency? If you are referring to comparable levels of sound output from similar drivers in two separate cabinets, I would think this has more to do with varying aged qualities of the 40 year-old drivers, unless the caps being compared had significantly different resistive properties. Anyway, while some of you wish to debate the merits of Dayton and Mundorf and Carli and Solen and Clarity or cap tolerance or whether to bypass or not (all healthy discourse, I suppose, but a bit superfluous here), I think there is a far more fundamental issue to be addressed here. This has been summarized in DavidR's first (now edited) post in this thread, which is exactly the point I tried to raise: Will this AR-9 tweeter work for this application

Our man Frank - - owner of a mountain of LST's and a bunker full of spare parts - - has asked for some frank advice before embarking on a coveted Frankenspeaker project. This premise is not a restoration project - - with the proposed tweeter replacement, it becomes a 'mod' and deserves close analysis and scrutiny before Frank turns his living room upside down and starts carving up his beloved (deservedly so :wub:) speakers to install 16 tweeters that just might not be suitable replacements, not to mention any possible crossover modifications required. Has this proposed installation ever been documented before? 

14 hours ago, frankmarsi said:

I’d like the AR-LST speakers to sound exactly as they do now...

I confess I am unfamiliar with the lab-based performance potential or possibilities of the 200029 tweeter, but in the five models where I believe it was used (AR-9, 90, 91, 92 and 58s), it was never designed to reach below 7000 or 7500 Hz, while all literature shows the AR-3a or LST midrange to extend only up to 5000 Hz. Unless I am missing something obvious, it seems to me this tweeter adaptation may create a very important and appreciable hole in your musical range, which would be fully unacceptable towards achieving the stated goal.

In the AR-3a restoration manual, the comment is made explicitly that the AR-9 tweeter (A.25 and A.26) was not designed for the 3a, and I believe this statement would extend to the LST as well. But could it work? I dunno, but where are the electronic geniuses and experienced speaker designers when you really need them? Even if this substitute tweeter can be made to work adequately, I doubt the results would provide an original LST sonic signature. 

AR-3a tweeter text.jpg

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Hi ar_pro, to listen to these speakers is heaven but, to move them about in any way is hell.

To bring these down the basement would actually be like slowly walking to hell because there’s no real good place for hand holding them not to mention the necessary twisting and turning once you do have them in your hands to negotiate doorways, etc. One does risk the chance of putting fingers where they shouldn’t be. And though, I’ve moved several in mine and their life time I’ve experienced smashed knuckles before with the accompaniment of undue pain just to spare the edges and finish of these small monsters was the price to pay.

Yes, you give good advice here but the reality is these are excellent speakers to listen to and enjoy but, they suck when it comes to moving them about. I had to place them in the trunk and back seat of my vintage Rivieras a number of times years ago but, these days I won’t take those chances because of the risk of personal injury.

But, I mustn’t find every excuse in the book, I’ve got to be strong mentally and physically to do this and I must do this as I have too many other aspects to enjoy in my systems like: a couple of mint vintage high-end tonearms. My huge record collection which has literally engulfed my world of stereo.

If you have any further suggestions, please keep me posted. I need all the help I can get.

Remember these may be my speakers but, you have debt to the world of AR speakers and this site.

Don’t you? (just kidding)

At ninety pounds each and with so few methods of carrying them, such unreasonable requirements are built-in with them. And yes, I will accomplish this feat as I owe it to myself and the world of listening that I enjoy so highly but, they can be like the 500 pound gorilla in the room. And there’s four of them staring at me constantly.

But, and there seem to be many of them, if I take my time, do one calculated operation at a time, I will succeed!

And in the end when the dust settles and the smoke clears, I’ll be one happy vintage loving, turntable spinning fool. When they are done, I’ll be rewarded with even more excellence of their performance. It’ll be a let down if when completed it turns out that a ‘cap’ in one of the channels in one of the driving amps is at fault. That would be an easier chore to handle by merely packing it and shipping it off to the original restorer for repair. This is the life’s work when using old vintage equipment and even though I persist in my enjoyment of such old equipment, the cost of newer more recent stuff is nonsense to me. And the further issue is; I truly have no desire to play with new stuff because first off, why would you, it’s new and second and the most important fact is that I’m completely enamored with the sound of these speakers and amps. Compounded by my love for vinyl and all things that relate to it.

O.K. so I’m a ‘throw-back’ but, that’s where I choose to be.

FM

P.S. ra.ra, I haven’t given what you speak of a thought but, now I’m curious that you may be absolutely correct.

Oh Shit! I better go do some yard work and think it all over.

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Does anyone know the crossover frequency of the AR-1MS?  It uses a 4" woofer crossed to a 0.75" fabric dome tweeter.  While I know it isn't an AR9 tweeter, knowing what frequency is used in the 1MS, might help determine how low a 0.75" dome can respond.

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5 hours ago, ra.ra said:

I don't even know what this means - - how does one gauge a capacitor's efficiency? If you are referring to comparable levels of sound output from similar drivers in two separate cabinets, I would think this has more to do with varying aged qualities of the 40 year-old drivers, unless the caps being compared had significantly different resistive properties. Anyway, while some of you wish to debate the merits of Dayton and Mundorf and Carli and Solen and Clarity or cap tolerance or whether to bypass or not (all healthy discourse, I suppose, but a bit superfluous here), I think there is a far more fundamental issue to be addressed here. This has been summarized in DavidR's first (now edited) post in this thread, which is exactly the point I tried to raise: Will this AR-9 tweeter work for this application

I'm not sure why either?  The original Unicon capacitors sounded fine, and I listened to the 58S's in the stock configuration for weeks, prior to the recap.  But, I knew they were old capacitors, and I didn't want to leave them as is.  So, after the recap, the speakers didn't seem as efficient.  I had to turn my Yamaha AVR to a higher read out, to match levels to what I heard before.  Maybe it was the upper mid suck out, I was hearing, making me feel the speakers seem different, not as loud as before.   The upper mids were very muted and dark.  The added volume could have been compensating for that issue?

Back to Frank.  You have the AR9 tweeters, try them.  If the impedance matches the original LST tweeters, it shouldn't hurt anything.  At worse, they'll be too bright.  But, they may surprise you, and sound much better.  Where's the harm?

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4-28-19 8:09 P.M.

O.K. one and all, it’s been a very good showing of members. I sincerely appreciate it!

Just finished mowing (picking up of scratchy balls that fall from ‘sweet-gum’ trees, a beautiful tree, straight and tall but, what a dirty bugger with those damn pointed balls) and in doing so I was apparently asking my 1978 Craftsman 16 horse-power tractor to be stronger than I thought it was, the belt that drives the dual mower blades came off, no doubt due to the scratchy balls that I hate so much and many twigs.Now with the grass growing at an accelerated pace, I’m in trouble.

I called my local repair man and of course, it’s the season and he’s-

too booked-up for three weeks which means I’m in trouble with the growth of grass and weeds that will probably be three times as hard to cut if and when I might get the mower fixed.

I have two metal drive on ramps and may attempt the repair myself but, I don't think the ramps will give me enough room to work, But, what about my ‘music is the drug’ situation?

I appreciate the show of hands on-board willing to give advice with my current dilemma, but I have one big question for all of you and anyone who’s watching in the wings, and that is: has anyone considered the symptoms of the problem before we all jump over-board?

Symptoms are, a low level hollow sounding intermittent ‘thump’ at moderately loud but, not excessively high volume levels.

When listening at ‘girly’ or low levels, there’s no noise of the thump but, when I do my usual realistic ‘manly’ sound level listening, I have the thump from ‘Thumpsville’ and it sucks because I’m still not completely certain if it’s a speaker ‘cap’ or a problem in only one channel in one of the amps. Like I said earlier, the amps were rebuilt to a more than expert status, by the great “Ed Blackwood” in 2009.

My thoughts are; it sounds like a capacitor or a car’s engine slightly mis-firing. Do capacitors display that sort of behavior at their age of 46 in a speaker? I have never heard such a thing myself but, at this point I rule out nothing.

Another pressing question is: will these AR-9 tweeters (if and when installed), have the ability to sustain my ‘realistic’ levels of output? If not, I’ve had no probs since 1974 with the “Micro-Statics’ handling my usual high-power input and they’ve sustained me thus far.

So you see, it’s not easy being me. With so many questions, such devotion to my ‘system’, coupled to any additional life’s problems and you’d understand. Not that I feel any of you don’t understand but, gee, one thing after another is not conducive to a happy and peaceful retirement for me. I realize many have a more difficult time at living life, but gees. Is it asking too much to want to listen to music?

I suggest that we haul the wagons into a circle, put on our ‘thinking-caps’ on, (no pun intended) and pool our vast knowledge, experience and resources together and figure out this problem cause it might happen to you, let’s hope not though. Yes, I may be asking a lot from all and any of you but, surely, someone has the answer.

FM

P.S. Wait! Look up into the sky! It's a bird, it's a plane, it's................................?

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