Jump to content

What to do with my AR93s speakers?


Guest MPPurcell

Recommended Posts

Guest MPPurcell

Very nice forum. I guess you can see that I am new here.

I acquired my AR93s's about 25 years ago, when I lived in Cambridge, MA. I've toted them back and forth across the country several times. Once I remember jamming these guys, plus my hi-fi electronics, my most choice records and precious few other earthly possessions I thought worth keeping into a little Nissan Sentra mini-wagon and driving from New Jersey to California. After the AR's and the vinyls, there wasn't much else you could get in there, but I knew what was important to me.

I guess the sound has been degrading over the past few years, less defined and fuzzier, particular in the low-mid and lows, but I was busy with other things and hadn't been paying so much attention. A few weeks ago I put on a Brahms Symphony for the first time in a long time. It sounded muffled, and then I heard a rattle and suddenly realized that one of them was "blown". I had gotten disconnected enough from my past by the progressive deterioration, and was tempted by the "new and better" that my first thought was, "Guess it's finally time for new speakers." But when I made the rounds of the Infinitys and Polks, and even Paradigms and others going into the thousands, I felt strangely dissatisfied with even the better models. The one thing I did find tempting, actually, is a pair of Magnepan flat panels I heard, with a subwoofer. A very different kind of sound, very clear and transparent. Well, I may be ready for that change, if it's not too great a shock to my system (though I can barely afford it).

At that point, ignorant of current attitudes of those knowledgable about speakers, I looked at my AR's and started thinking, "What am I going to do with these, though?" I started to figure they might be valuable to someone. I mean, look at these cabinets alone. For those who might not be familar with the 93s, it is not the most classic AR, but it may be one of the most beautiful speakers ever made. The cloth surround, sculpted edges and walnut top are rather elegant. These 3-ways have an 8" mid cone, and two more 8" cones that do woofer duty, one on each side. Maybe this is not the cleanest speaker ever made, but there is a warmth, expansiveness and ambiance that I have heard from very few towers, and within that context, they actually sound remarkably clear. --Or rather, mine used to sound that way. So I started thinking, I wonder if there is any way of fixing these things.... Maybe there is even a way of using these amazing cases, and even improving the sound, like some folks are doing with classic amps these days.... By such a route, I gradually found my way here.

As I see it, I have several options:

1) I could throw them in the trash. (Honest, when I started thinking about this, I had no idea if they have any value.)

2) I could look for a buyer who could turn them into something great again and try to raise some cash for the Magnepans.

3) I could try to get them repaired or even upgraded and keep them myself.

With option 2 or 3 above, I retain deeply the knowledge that these suckers weigh over 50 pds. each (without cartons), so properly packing and shipping them somewhere for sale or repair, and shipping them back could be risky and eat up a lot of funds just moving them.

So one question I have (after your thougths on the value of repairing these) is: do any of you know of someone with experience in the craft anywhere in Northern CA, preferably around Sacramento? Otherwise, anyone else out there willing to work with me from a distance? I am actually fairly handy, but I don't really have the time to do all the learning, figuring and leg-work this would require to figure out myself.

What advice do you have--what should I do?

Thanks,

Michael

Link to comment
Share on other sites

>Very nice forum. I guess you can see that I am new here.

>

>I acquired my AR93s's about 25 years ago, when I lived in

>Cambridge, MA. I've toted them back and forth across the

>country several times. Once I remember jamming these guys,

>plus my hi-fi electronics, my most choice records and precious

>few other earthly possessions I thought worth keeping into a

>little Nissan Sentra mini-wagon and driving from New Jersey to

>California. After the AR's and the vinyls, there wasn't much

>else you could get in there, but I knew what was important to

>me.

>

>I guess the sound has been degrading over the past few years,

>less defined and fuzzier, particular in the low-mid and lows,

>but I was busy with other things and hadn't been paying so

>much attention. A few weeks ago I put on a Brahms Symphony

>for the first time in a long time. It sounded muffled, and

>then I heard a rattle and suddenly realized that one of them

>was "blown". I had gotten disconnected enough from my past by

>the progressive deterioration, and was tempted by the "new and

>better" that my first thought was, "Guess it's finally time

>for new speakers." But when I made the rounds of the

>Infinitys and Polks, and even Paradigms and others going into

>the thousands, I felt strangely dissatisfied with even the

>better models. The one thing I did find tempting, actually,

>is a pair of Magnepan flat panels I heard, with a subwoofer.

>A very different kind of sound, very clear and transparent.

>Well, I may be ready for that change, if it's not too great a

>shock to my system (though I can barely afford it).

>

>At that point, ignorant of current attitudes of those

>knowledgable about speakers, I looked at my AR's and started

>thinking, "What am I going to do with these, though?" I

>started to figure they might be valuable to someone. I mean,

>look at these cabinets alone. For those who might not be

>familar with the 93s, it is not the most classic AR, but it

>may be one of the most beautiful speakers ever made. The

>cloth surround, sculpted edges and walnut top are rather

>elegant. These 3-ways have an 8" mid cone, and two more 8"

>cones that do woofer duty, one on each side. Maybe this is

>not the cleanest speaker ever made, but there is a warmth,

>expansiveness and ambiance that I have heard from very few

>towers, and within that context, they actually sound

>remarkably clear. --Or rather, mine used to sound that way.

>So I started thinking, I wonder if there is any way of fixing

>these things.... Maybe there is even a way of using these

>amazing cases, and even improving the sound, like some folks

>are doing with classic amps these days.... By such a route, I

>gradually found my way here.

>

>As I see it, I have several options:

>1) I could throw them in the trash. (Honest, when I started

>thinking about this, I had no idea if they have any value.)

>2) I could look for a buyer who could turn them into

>something great again and try to raise some cash for the

>Magnepans.

>3) I could try to get them repaired or even upgraded and keep

>them myself.

>

>With option 2 or 3 above, I retain deeply the knowledge that

>these suckers weigh over 50 pds. each (without cartons), so

>properly packing and shipping them somewhere for sale or

>repair, and shipping them back could be risky and eat up a lot

>of funds just moving them.

>

>So one question I have (after your thougths on the value of

>repairing these) is: do any of you know of someone with

>experience in the craft anywhere in Northern CA, preferably

>around Sacramento? Otherwise, anyone else out there willing

>to work with me from a distance? I am actually fairly handy,

>but I don't really have the time to do all the learning,

>figuring and leg-work this would require to figure out

>myself.

>

>What advice do you have--what should I do?

>

>Thanks,

>Michael

>

Hi Michael;

Welcome.

First off you will learn a lot from coming here, not necessarily tonight alone though.

Magnepans are electrostatic speakers and are clearer.

What you are describing, is the woofers, at least, suffering from foam rot.

The woofer cones are flapping in the breeze and buzzing and rattling around.

Do not use them at anywhere near loud as damage is being done.

The surrounds are a foam, which over time, disolves.

The good news is if the voice coils are not burnt, they can be re-foamed.

If you are willing to do the work, it will cost you about $5 - 10.00 each for the foam surrounds.

There is a lot of discussions here regarding re-foaming and also several sources for buying and maybe a few for doing that service as well.

Help will be forthcoming as members see your topic.

Good luck and please keep us up to date with your progress.

Link to comment
Share on other sites

This is a good place to come to regarding restoration of old loudspeaker system, especially AR. There will be a lot of good advice and sources of help. Restoring the drivers will be something which requires some skill and you may want to get professional help with this. The results will depend on the degree of skill applied to the job. You may also want to look at the electrolytic capacitors in the crossover network. We've had some discussions here and there are different theories about whether or not it is valuable or even wise to "upgrade" to polypropylene capacitors but there are widespread reports that the old electrolytic caps can change value over time altering the audible performance and even risking damage especially to tweeters.

Magnepan speakers are "magnetoplanar" not electrostatic and do not work on the same principle. What they have in common is that they make sound by vibrating membranes having a large aggregate area over a relatively small distance rather than small area cones or diaphrams over a relatively larger distance. Many are bipolar radiating both front and back. As such, they have entirely different radiating characteristics and as expected sound different from "box" speakers. The conventional wisdom regarding their clarity of sound is that they supposedly have very low harmonic distortion but personally, I feel it's the radiating pattern itself which accounts for most of this (I am in the clear minority on that one.) You can approximate this by building array type dynamic speakers but there doesn't seem much current interest in that at the moment. Another common theory is that their lack of a "box" enclosure eliminates many box resonances which their advocates find annoying. It is possible that the array configuration excites room resonances differently than box speakers which is an alternate theory about their lack of annoying resonances. They have special installation requirements including the need to be placed 3 or more feet from the wall behind them and often have a low WAF (wife acceptance factor.) They have limitations on both low and high frequency reproduction and are therefore often teamed with subwoofers and ribbon tweeters usually in a linear array. The also have limitations in dynamic range (maximum loudness) and therefore the larger units are preferable. They are not suitable for music requiring very loud playback such as rock music. I don't think they are particularly efficient and require relatively powerful amplifiers which is not the problem it once was unless you are a fan of SET (low power single ended vacuum tube triode) amplifiers. They are not a good match for those.

Link to comment
Share on other sites

Michael,

It’s great that you were able to find your way here.

My comments are going to be very general as I have no experience, at all, with AR-93s.

All six 8" drivers either need to be re-foamed or will soon need to be. Having someone else do it will likely cost in the neighborhood of $35 per driver. So we’re talking $200+ to have it done. You can do it yourself for closer to $60-80 and a few evenings’ effort.

I am not sure what values of capacitor are used in the AR-93's crossover.

My experience with five pairs of speakers is that the capacitors need to be changed. You will get an improvement in sound replacing the old capacitors with even cheap non-polar electrolytic new capacitors. You are likely to experience an epiphany of sorts, “Good grief! How was I ever listening to these like they were?” This is an easy, cheap, repair.

What’s cheap? Since I don’t know what values you need, I’ll tell you that they will almost certainly be less than $45 per speaker, maybe half that.

There are people here who have restored many, many more than I have. Hopefully they will jump-in with their experiences.

It is impossible, or at least supremely unfair, to compare the way your speakers sound right now to anything you might decide to purchase as replacements. You really have to do at least the minimum repairs to know what they sound like.

If you like(d) the sound of the ARs, I have to stretch my imagination almost to the breaking point to think that you would be happy in the long term replacing them with any planar speaker.

Bret

Link to comment
Share on other sites

Guest MPPurcell

Dynaco, Soundminded and Bret,

Thanks for your help.

I do suspect that after 25 years, the foam has deteriorated on the woofers. I tried to peer through the grill cloth with a flashlight and could not see any obvious damage--I suppose that's good. Right now, I am only getting actual rattling on specific very low tones, otherwise the lower sounds are simply distorted and muddier than I would like. I have never played these speakers extremely loudly, but when I discovered this, I moved the balance over to the other speaker--so one side now plays at much less volume, and I am being careful about keeping them at lower levels. I checked the rattle carefully. What is interesting is that it seems to be coming from both side-firing 8" woofers on one speaker only, and not from the 8" that acts as midrange. Because of this, I am actually wondering if there is a problem in the crossover.

How do we know that the voice coils are not burnt? What would it sound like if they were?

I think I may be able to do the re-foaming of the 8"s myself, given some good guidance and a couple of caveats. First, I cannot figure out (Step 1) how to remove the grill cloth without damaging it. It is tightly wrapped all the way around and stitched straight down the middle of the back. In one article I found a link to a page about refurbishing an AR94. There I noticed in a photo that the cloth had been released at the top and pulled down to the bottom (like someone having dropped their pants) to expose the cones. However, I can't figure out how to detach it at the top without cutting, ripping or otherwise damaging the cloth, nor how to reattach it again. (Does the top cap of the speaker, the part with the nice walnut veneer, somehow pop off first? Just figuring out how to get into these to get started is something of a puzzle.) I also have seen a lot of references here to replacing the foam, but I have not seen specifically where to get the right foam. In general, I have read a lot of posts and seen many helpful tips, but I have not yet been able to find the specific instructions, sources of parts (other than Parts Express, which seems like electronics--I am not sure if they would have what I need) or names/locations of professional repair people or experienced AR hobbist that could help. Can you give me some specific URL's or even search terms, or ways to find these contacts?

Dynaco, I like the idea of fusing my speakers for the future, in the process of getting these repairs made.

Soundminded, I did some research on the Magnepans. I can agree with most of what you say, including the WAF problem. My wife has never objected seriously to the AR93s's, except a little to their size, because they look so good. Initially, talking about flat panels did meet some resistance. But Magenpan now has some smaller panels that you can mount on a wall by one edge. When not playing them, you can simply fold them back against the wall, so they are rather unobtrusive--they look like decor. When playing, you fold them out again from the wall at 30-45 degrees, and they produce sound that is partly reflected obliquely off the wall (since they radiate from both sides). It is indeed a clear sound, but lows are inadequate without a subwoofer. A ribbon tweeter is built in, so these are not deficient in highs. Regarding your comments on arrays: Long ago (long before center channels came in) I created a setup with four separate front speakers--two smaller R & L 2-way mid/tweeter ones about 5 feet apart and bigger 3-way main speakers about 9-10 feet apart--so, a lot of drivers altogether, and spread out. Typically, the inner left and right speakers are kept at lower volume. If well done, this can give an incredibly smooth and wide dispersion of sound, particularly for symphonic music, without any weird tricks like simulated sounds coming from behind you.

Bret, my view is that if I am going to go through the trouble of opening these up, I might as well do everything that could be needed for at least 20 more years. Capacitors for sure--that may be a big part of my problem with the low notes. I also like your thinking about repairing them first, then seeing if I would rather sell them for a different kind of sound.

I have been wondering (once I figure out how to get through the grill cloths) if I could just remove all the speakers and crossover parts (taking photos along the way) and send them to someone experienced to examine them and replace what is needed. I could receive them back and reinstall the whole rig, if that seems feasible. I think such an arrangement might better fit my available time right now. Possibly I could do the refoaming first, then send it all to someone to check my work and do the electronics and silver-braided wiring properly.

Hey, I seem to remember it is possible to post photos on this site? I might take a couple and try to put them up here.

Thanks all,

Michael

Link to comment
Share on other sites

Michael,

Attached are a couple of photos of the bottom of an AR-94 that may be of assistance in getting into your 93's.

The cloth is stapled in place under the plastic base, which is held in place by four screws. I don't know how the top of the cabinet is attached (possibly screws inside the cabinet?), but it would only have to be removed to replace the cloth.

Roy

post-101150-1134256509.jpg

post-3-1134256509.jpg

Link to comment
Share on other sites

Guest MPPurcell

>The cloth is stapled in place under the plastic base, which is

>held in place by four screws.

Eureka! They're hidden in the feet in the base? That helps unravel the mystery.

To help protect our wood floor against scratching, and give a little isolation to the speaker, we glued felt pads to the plastic feet many years ago. Therefore, when I turned the speaker over, I could not see the screws. I will look on Monday, and see if I can get off the base and lift up the cloth like a skirt (rather than dropping it like pants--sorry for all the voyeuristic metaphors!)

With luck, soon I will have a better look at these drivers and have a better idea of how much work this project is going to be.

Thanks for the tip.

Michael

Link to comment
Share on other sites

>What advice do you have--what should I do?

As others have suggested, the least-expensive way to get back into business would be to re-foam the bad surrounds on your AR-93s. The “fuzziness” you describe almost certainly is due to deteriorated surrounds on both the midrange driver and the two woofers. The crossover and individual drivers may be at fault, but I could start with the surrounds and see where that leads you. There are some philosophical differences, however, that might be even more important to consider.

Magnepans are fine speakers, but there is a huge difference between the design-philosophy of Magnepans planar speakers and the AR-93s, and it raises some fundamental issues: (1) the Magnepans are highly directional speakers, and even though they do radiate off the rear of the enclosure creating a quasi-figure-eight radiation pattern, speaker placement is critical to the proper sound. Placement, toed-in well away from room boundaries and out into the room, is simply de rigueur. Exceptions to this placement result in greatly impaired performance, so the room in which they are placed now becomes -- by default and regardless of whether or not you chose it to be – a dedicated “sound room.” (2) These speakers also require that you sit in a designated position – a “sweet spot” – in line with the speaker axis, a certain distance from the speaker, in order to get a reasonable sound presentation. If you move out of this area the “image” is lost and the speakers take on a very two-dimensional sound. As you move *back* into the room’s reverberant sound field the Magnepan’s sound becomes less focused and duller due to rapidly diminishing acoustic power radiated into the room. Therefore, you must sit in a specific seat each time you wish to listen to them. The question then arises, why not just put on a pair of Sennheiser SD600 headsets? At least you could move around a bit. (3) Magnepans are relatively inefficient – they require fairly hefty amplifier power, but they do not tolerate high amplifier… an oxymoron of sorts. So care is required to prevent distortion in the panels. Or in other words, you cannot crank up the volume too much without fear of distortion and/or damage to the panels. (4) Magnepans have roll-off in the low and high frequencies, and therefore usually require at least a subwoofer to reinforce bass frequencies below 50-60 Hz. Bass drums sound like kettle drums on a panel speaker, so a subwoofer is necessary to restore the deep-bass below 50 Hz. Subwoofers can work extremely well, but matching the output of one to the other requires a subwoofer with a built-in amp with variable high-pass crossover, phase control and output level. This means a fairly substantial subwoofer, and these don’t come cheaply.

On the other hand, you could just get your AR-93s refurbished by re-foaming the surrounds on the midrange driver and woofers. The 93s have excellent low bass due to the two side-mounted 8-inch woofers, and these units are almost the equal of the AR speakers with 12-inch woofer. Side-mounted woofers eliminates for the most part the boundary-interference effect (the “Allison Effect”), so the mid-bass is very uniform and accurate. Repairing the cones would restore the missing clarity, and you would be back in business. The bass response would be much superior to the Magnepans (before subwoofer), and the high frequencies are so well dispersed that the speakers give a good illusion of space. They don’t have to be toed-in; no “cat-bird” seat is required; no special listening room would be required.

If you must have a Magnepan-like imaging, which can actually "grow old" after awhile, you could invest in a good pair of headphones and save yourself a lot of money and possibly “misery” with other family members. When you are not listening to the headphones, turn on the refurbished AR-93s and enjoy listening to that natural “AR sound.”

--Tom Tyson

Link to comment
Share on other sites

The more experienced I've become as a listener, the less importance I place on "imagaing." I'm not even sure there is agreement on what this word means as it relates to sound reproduction. I've come to see it as a catchall phrase which has become a mantra for audiophiles and advertisers alike since every one of them can use this buzzword to mean almost anything they want it to mean. If it means the localization of sound slightly further to the left or the right, closer or farther away, I cannot imagine what importance this could have that is of any significance. I have always found the stereophonic effect adequate within the two channel context recognizing its inherent severe limitations in that once you move away from a favored listening position, human hearing easily detects an apparant shift in the direction of the source. This is due to the fact that the psychoacoustic phenomenon depends on the brain creating phantom sources which trick it into concluding sound is coming from a direction which is not that of the speakers because of a differences or similarities in the loudness and time of arrival of similar sounds at each ear. These create the illusion of directionalities. In small rooms, moving slightly to the left or right changes that relationship radically enough to alter the perception. OTOH, if imagaing means reproducing the acoustics of a live venue in the home, that is well beyond the current state of the art and the greater the difference between the size of the live venue and the size of the home listening room, the more preposterous the attempt using current methods and the more obvious the failure is to those who frequently hear live music in rooms specifically designed for musical performances.

For me, I am satisfied if the majority of recordings I listen to have reasonably close timbral accuracy of most instruments most of the time throughout their frequency and dynamic range and can be heard clearly and distinctly from one another when playing ensemble. This too seems well beyond the capability of most home sound systems despite the possibility that it is within the realm of the current state of the art. If this was AR's goal at least for a time, they were IMO on the right track and proved it to themselves and their market by comparing their speakers to live music. Most other manufacturers seem entirely indifferent to this goal depending for commercial success on designs which are initially ear catching to the inexperienced listener or those who don't know or care what timbral accuracy means and on lauditory reviews in hobbyist magazines. If the price of "imagaing" whatever that means is timbral accuracy, it's a trade I for one would not usually choose to make.

Link to comment
Share on other sites

You should try to restore them.

This is what I did with my AR98LS seakers:

http://www.kujucev.com/ar98ls/ar98.htm

After restoration they sound like a totally different pair of speakers.

Before that, they sounded harsh, with weak bass.

Top quality polypropylene caps and new wiring made a huge difference!

They needed around 100 hours of playing music for "run-in".

Their sound is still changing for the better.

Good luck,

Aleksandar

Link to comment
Share on other sites

Guest MPPurcell

Thanks to Tom for the advice and further illumination on planars versus AR speakers, and to Kuja for your inspiring page on your success with rebuilding.

For those who have not seen the AR93s speaker, I am attaching a photo of one of mine. After taking this photo, I noticed something I had not seen through the grill cloth before--it looks like a dislodged piece of foam by the tweeter. (The other speaker was the one I examined more closely.)

The second photo is the second of the pair--the one that was rattling--turned upside down, with the grill cloth pulled up (down, in this position). When I removed the cloth, I was quite shocked to see how bad the damage to the foam is on all three 8"er's--it is amazing that they played as well as they did. (Some of what you see may be the coup de grace from jostling the cones by turning the speaker upside down and pulling down the cloth. I could not see this damage when I looked through the cloth with a flashlight!)

Okay, guys, you've got me hooked. Thumbs down to planars--I've got see what these AR's will do if I refurbish them. The first order of business is to replace the surrounds. I've got six 8" speakers to do. By the time I am done, I should know how to do it well. Can someone advise me of the best way to get replacement surrounds quickly so I can start working on this? Also, I will search the site to find references about how to do it, but if anyone can send me the URL to a page that details the process, step by step, I would sure appreciate it. My email address is also listed with my user info.

I will keep you posted how it goes.

Many thanks,

Michael

http://www.classicspeakerpages.net/dc/user_files/757.jpg

http://www.classicspeakerpages.net/dc/user_files/758.jpg

post-101593-1134430249.jpg

post-3-1134430249.jpg

post-3-1134430250.jpg

Link to comment
Share on other sites

Michael,

A good source of surround kits for AR speakers, and one I have used for several years is:

Speaker Works Northwest

2642 Almaden Street

Eugene, OR 97405

www.speakerworks.net

(541) 687-0200

You should measure your existing 8-inch drivers for the inside-diameter of the foam surround/cone junction and the outside diameter of the surround. Give them a call and they can lead you through that process. You will probably want the "angled" inner-flange-type surround, and they will know what you are talking about. The 12-inch AR woofer surround kits I have used are $24.00, but I suspect that the 8-inch kits are less; besides, they will reduce the total price when you order more than one. These kits use the preferred water-based glue, and do *not* require -- not do they recommend -- the use of shims in the voice coil. Remember, you will need to replace the surrounds for all six drivers in your pair of AR-93s. Speaker Works Northwest has an excellent set of instructions, as well, so you won't have any trouble if you are patient and follow the instructions carefully.

--Tom Tyson

Link to comment
Share on other sites

Michael,

I have to 2nd Tom on Speaker Works Northwest. I have dealt with them a number of times and they are very helpful and prompt in their shipments.

http://www.speakerworks.net

They also have a video clip that you can download showing the process of replacing your surrounds. Check it out.

http://www.speakerworks.net/repair_video.html

Good luck and keep us informed.

James

ps - just getting ready to refoam a pair of 10" AR-2AX woofers with surrounds from them.

Link to comment
Share on other sites

If you are looking to save money you can get the 8" surround from MAT Electronics--800-811-5177--they sell it for .99 and if you buy 10 or more .90. Make sure you get the glue from them also. They have a min order of $25 so you will have to order some other items. They also have a web site.I have used their surrounds for a bunch of AR speakers. They don't have the surround for the AR 12" woofer.

Link to comment
Share on other sites

Guest MPPurcell

I posted a reply to Tom earlier today, but somehow that post never made it onto the forum. Here's pretty much what I said:

Thanks, Tom (and now James and Supercooper), for the suggestions. I phoned Speakerworks and talked with someone about getting foam for the drivers. I also spoke with Bill of Millersound in PA about sending the speakers to him. He came so highly recommended by so many posters, I just had to talk to him. I was duly impressed, and am now leaning towards letting Millersound do the job for me, instead of doing it myself. His prices are very reasonable. The only hesitancy is the weight and packaging of sending 6 woofers across the country, but I think I am resolving that one.

When I pulled the grill cloth off of the second speaker, I found this tweeter was slightly dimpled. I may try wetting it a little and sucking it back out with a straw, as I have seen recommended.

Thanks to all who have helped. It may be a couple of weeks now before I can tell you the result of the refoaming.

Michael

Link to comment
Share on other sites

>He came so highly recommended by so many posters, I just had to talk to him. I was duly impressed, and am now leaning towards letting Millersound do the job for me<

I don't really want to sound like a commercial, but I suspect you would be very happy with his work.

Bret

Link to comment
Share on other sites

One big advantage to Millersound is that along with high quality work, Bill is easy to reach and very communicative. This is not true of many of the alternatives out there. I found it informative and reassuring to speak with someone with as much experience as he has.

The outcome is never in doubt as he tests/measures the drivers for proper performance before returning them.

End of commercial:-).

Roy

Link to comment
Share on other sites

Guest MPPurcell

I have sent all 6 of my woofers and mid-range 8" drivers off to Millersound. Speaking to him was very reassuring, and the comments here on the forum and by individuals also made me feel I was most likely to end up with the most reliable and sound (sorry, no pun intended!) finished drivers. Not only that, his pricing is very reasonable.

Now: Tweeter issue.

Meanwhile, one speaker has a tweeter that has a small dimple of about 1/4" or slightly larger in the center. After reading on the forum a bit about this, I tried sucking it out with a straw, but without wetting the dome at all. (In other words, I have only tried the most minimally invasive procedure so far--hey, my woofers are out of the picture for the next 10 days to 2 weeks, so there is no big rush. I am going slow on this.) I think I got pretty good suction with the straw, but the dome did not budge. I am wondering about some alternative methods, and what other advice you have for me on this.

So far, I have come up with three alternatives:

1) I could do nothing--maybe that little dimple is not affecting the dispersion of highs anyway, and doing nothing is the best way of not making anything worse.

2) I could get the dome wet for a little while, and then try sucking it out. (I wasn't sure if the point of wetting it was to give greater suction because of making a better seal, or because it temporarily would soften the dome and make it pliable to move more easily. I didn't seem to have much trouble with suction and a good seal, and I tried with several different sized straws.)

3) I could use a small needle, poke a tiny hole near the edge of the dent, and push the needle through enough to move it sideways and lift the center of the dome up. In this (somewhat scary but possibly effective) scenario, I would then withdraw the needle and perhaps touch the hole with a tiny bit of wood-glue to close and seal it again.

I would like to hear reactions to these ideas, and/or what sequence to try them, or any other notions about what to do about the dimple.

Thanks,

Michael

Link to comment
Share on other sites

>I would like to hear reactions to these ideas, and/or what sequence to try them, or any other notions about what to do about the dimple.<

Can you post a photo of the driver?

The place and extent of the dimple may vary the suggestions you get.

Bret

Link to comment
Share on other sites

Guest MPPurcell

Here are a couple of close-ups of the tweeter with the dimple. I hope this works, I am still trying to understand how the attachment system works here.

Michael

post-101593-1135031373.jpg

post-3-1135031373.jpg

Link to comment
Share on other sites

>Here are a couple of close-ups of the tweeter with the

>dimple. I hope this works, I am still trying to understand

>how the attachment system works here.

>

>Michael

>

>

Hi Michael;

Nice photos, Michael.

The dimple is not too serious in appearance, in my opinion.

If it is functioning ok, I would suggest just ignoring it, unless you can buy a replacement tweeter.

Even the slightest force may deform it and cause it to rub.

There has been several suggestions made regarding removing dimples.

One was wetting it and sucking with a straw.

Like I say if it works, just leave well enough alone.

Good luck with your decision.

Link to comment
Share on other sites

  • 2 weeks later...
Guest MPPurcell

My 8" drivers (six of them) are now on their way back from Millersound, so I should be able to install them next weekend. One thing I have gathered from following this site and interacting with so many fine AR audiophiles while getting help with my AR93s repair is that this appears to be not a very well-known AR speaker. It may have had a limited production run (around 1982), but I now suspect it may be a much better speaker than most people realize, or even I realized! I got so used to them that it was only when I went out shopping for speakers that I started to realize what I have.

A few days ago I took out some batting to see what the crossover looked like. I unexpectedly discovered that the midrange is mounted in its own separate cylindrical acoustic box (which has its own bat of insulation inside) It even feels like the hole through which go the wires to the mid-range is sealed with glue--they are not loose or mobile through the hole. I am wondering how common this was in AR speakers. The mid-range definitely appears to have its own separate small acoustic suspension box. I am attaching a photo of the enclosure inside the enclosure.

Michael

post-101593-1136196059.jpg

Link to comment
Share on other sites

Guest AR-MST-PICCO

The cylindrical acoustic box is common in AR 3 and 4 ways system. For example AR98LS, 9LS, etc. I owned AR 98LS and keep this speaker for my personal collection. When I was young, I listened the AR93s from my cousin house. His font end is Sony Esprit series Pre amp + power amp. There is no CD player at that time. I can't forget the bass and punch from AR. I like AR speaker system. My font end is conrad johnson (PV-2a + MV-75a-1).

Link to comment
Share on other sites

Guest westarch

Michael,

I've got a pair of AR 94's (don't have the double side-throw woofer config on the 93) and I appreciate your post and the replies that have followed. I'm trying to figure out if it's better to refoam or replace the drivers on my speakers. Got a separate post for that one under Mods, Tweaks & Upgrades. I'll be following your progress with the repaired drivers...

What did you decide to do with the dimpled tweeter? One of mine is in worse shape than yours, but I have to say I never noticed it sounding bad. Tried the straw trick but didn't get enough suction to fix it. Is the general consensus to leave good enough alone?

Good luck and thanks for your help!

-Doug

Link to comment
Share on other sites

Guest MPPurcell

>When I was young, I

>listened the AR93s from my cousin house. His font end is Sony

>Esprit series Pre amp + power amp. There is no CD player at

>that time. I can't forget the bass and punch from AR.

This is the first reference I have heard of anyone else owning an AR93s speaker system, or a memory of listening to one. Was this in the Boston area? I am trying to figure out how far ranging sales were for this model, and how it was considered when it came out.

Michael

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...