Help with AR-2ax Speakers bought from Heathkit

[Tmc]

Hi,

Newbie here.  I just found this forum and have spent half the day reading and reminiscing.  In the 70’s, I purchased a pair of AR-2ax speakers (floor display) at a Heathkit Electronics Center in Houston.  I still have the sales receipt.  Unfortunately, the date reads as 10/14/7T, so I cannot tell if I bought them in ‘71 or ’75.  IIRC, Heathkit used to sell kits for the AR2 and AR3 speakers, but I am fairly sure the ones I purchased were not built from a kit.  That said, mine seem to differ in many ways from the AR-2ax speakers I have seen posted on this site.  The backs of mine are not plywood, but a fiberboard type material.  The serial number that is still partially readable looks as if it was typed on a strip and pasted in place and the paper itself is not as large and of a more complex design than most I have seen.  The speaker badges have raised lettering and plastic backings with a post that fits through a hole in the grill that is secured with a push washer allowing them to rotate.   The grills attach to the speakers with Velcro tabs instead of staples. 

In 1995, the foam surrounding the woofers was crumbling and the pot adjustments not working well.  I took the speakers to a local sound shop to be reconditioned and re-foamed/re-coned.  The shop mentioned part(s) needed to be replaced and said they might not be able to match the original bass sound of the speakers.  I remember being sorely disappointed and reluctantly giving my okay for the repairs.  I suspect they replaced or repaired the pots and replaced the tweeters, as the black tape that used to cover the wires leading from the tweeter fronts is missing and there are no connections made there.  As you can probably tell, I am not very speaker savvy.  At that time, I replaced the speaker grill cloth with linen from Hancock fabrics.  I wasn’t trying for an identical match, just wanted a material that looked nice and clean.  I see now there is fabric available from 123 Stitch that is close to the original.

A short time after the repair, I put the speakers in storage as I moved frequently and either did not have the space or the time to set up a stereo system.  Now that I am settled, I hooked them up to a Sony AV/500.  They sound okay, but lack the bass and depth that I remembered.  I’ve taken pictures and posted a link to them (below) in hopes that someone on the forum can give me an idea of what I actually have, i.e., the condition of the speakers and which part(s) are original and which are not.

http://thegoldenflower.net/AR-2ax_02.html

If feasible, I would like to restore the speakers inside and out, replace any substitute parts with genuine AR.  I don’t know much about electronics but am willing to learn.  My husband will help and I can see there is a lot of information on the forum.  I have bookmarked, downloaded and read the article on the AR3a restoration, which motivated me to give all this a try.  Any and all help, comments, and advice from you guys/gals on the forum will be sincerely appreciated.

Regards,

Tmc

 

[Aadams]

TMC

Your 2axs are a somewhat odd mix but nothing in the photos would suggest they are not genuine AR.  

Your original tweeter has been replaced with a back wired version that appears to be an AR replacement but not like the original.

The woofer foam replacements are not of the most favored type these days but they are good enough for decent bass and nothing in the images suggests why you would be missing "bass and depth".

The pots could be original. Externally they appear correct but, do they have any effect on the sound of the speaker when they are rotated?

Are you sure all of the drivers have output?

Are you sure there are no leaks around the woofer gasket?

Do you know if the original capacitors were replaced?

Something could have been wired incorrectly when the repairs were done

You may have to remove the woofers and look inside the boxes to resolve or even find the solution to your problem.  You will get plenty of good advice here but be ready to supply images if you are going to do this yourself.

Aadams

 

[lARrybody]

I agree with Aadams that your 2ax speakers appear to be all AR. The tweeters look like what you might find on some AR 11's or 12's. Still 3/4 in domes ,just from a later generation. The woofers look good, the surrounds look like the roll is a little narrow. Good news is that the more desired surrounds are available. I would get a empty paper towel tube and listen to the mid and high drivers while adjusting the potentometers. The potentometers are the week link in the AR2ax chain and corrode and drop out all the time. They can be replaced if not repairable with L-pads or better yet 15 ohm 25 watt rheostats. There is a lot of music reproduction left in your speakers. Oh, by the way welcome to CSP and I can assure you this is the right place with the best knowledgable people willing to help. 

[Aadams]

Tmc

Re: The bass.  Do you have the speakers connected identically to your Sony?  + and - or red and black should match.  Your woofers could be wired internally opposite also which would weaken the bass even if they are wired correctly externally.  

[Tmc]

Aadams,

Thank you for your quick response to my inquiry.  I was a poor student in the 70’s and saved for a long time to get my AR speakers.  In fact, I had them for months before I was able to purchase other components to get them up and running!  Having to replace original parts in ’95 broke my heart, but at the time I did not realize I had other options.  Wish I had known about this site then.  I am happy to hear that aside from what was replaced you believe my original purchase was genuine. The speakers do look different in many ways from most of those I see on this forum, so I was a bit worried.

As far as I know, the pots are original.  When I brought the speakers in for repair, the pots were intermittent, you could touch/wiggle the knobs and produce static and at certain stations on the knob turns, sounds would cut out – not generate.  I am guessing they were cleaned as currently they seem to be working okay and do enhance or decrease the speaker sound.  
I intend to remove the woofers and look inside the cabinets, however, I am hesitant to do it by myself, so need to wait for a sunny weekend and get my husband to supervise.  The most worry I have is removing the “rock wool” fiberglass type stuffing. But, I am curious to see what has been done inside.  I will definitely photograph each stage.  Tomorrow, I will take a closer look at the woofer gasket and play some more with the pots and check the speaker wire connections.  Thanks for the advice and reassurance.

Tmc

IARrybody,
Thank you for the welcome to the forums and your response to my questions.  Replacing the woofer surrounds may be a  good place for a beginner like me to start.  What, if I may ask, are the more desired ones?  I plan to look inside the cabinets and will definitely document each step with pictures.   I love the speakers and wish them to sound their best.  I just need a bit of guidance in getting to that point ;0)

Tmc

Aadams,

I am fairly sure the speaker wires are connected correctly, but I will double check.  Thanks for the reminder.

Tmc

[tysontom]

8 hours ago, Tmc said:

Hi,

Newbie here.  I just found this forum and have spent half the day reading and reminiscing.  In the 70’s, I purchased a pair of AR-2ax speakers (floor display) at a Heathkit Electronics Center in Houston.  I still have the sales receipt.  Unfortunately, the date reads as 10/14/7T, so I cannot tell if I bought them in ‘71 or ’75.  IIRC, Heathkit used to sell kits for the AR2 and AR3 speakers, but I am fairly sure the ones I purchased were not built from a kit.  That said, mine seem to differ in many ways from the AR-2ax speakers I have seen posted on this site.  The backs of mine are not plywood, but a fiberboard type material.  The serial number that is still partially readable looks as if it was typed on a strip and pasted in place and the paper itself is not as large and of a more complex design than most I have seen.  The speaker badges have raised lettering and plastic backings with a post that fits through a hole in the grill that is secured with a push washer allowing them to rotate.   The grills attach to the speakers with Velcro tabs instead of staples. 

 

In 1995, the foam surrounding the woofers was crumbling and the pot adjustments not working well.  I took the speakers to a local sound shop to be reconditioned and re-foamed/re-coned.  The shop mentioned part(s) needed to be replaced and said they might not be able to match the original bass sound of the speakers.  I remember being sorely disappointed and reluctantly giving my okay for the repairs.  I suspect they replaced or repaired the pots and replaced the tweeters, as the black tape that used to cover the wires leading from the tweeter fronts is missing and there are no connections made there.  As you can probably tell, I am not very speaker savvy.  At that time, I replaced the speaker grill cloth with linen from Hancock fabrics.  I wasn’t trying for an identical match, just wanted a material that looked nice and clean.  I see now there is fabric available from 123 Stitch that is close to the original.

 

A short time after the repair, I put the speakers in storage as I moved frequently and either did not have the space or the time to set up a stereo system.  Now that I am settled, I hooked them up to a Sony AV/500.  They sound okay, but lack the bass and depth that I remembered.  I’ve taken pictures and posted a link to them (below) in hopes that someone on the forum can give me an idea of what I actually have, i.e., the condition of the speakers and which part(s) are original and which are not.

http://thegoldenflower.net/AR-2ax_02.html

If feasible, I would like to restore the speakers inside and out, replace any substitute parts with genuine AR.  I don’t know much about electronics but am willing to learn.  My husband will help and I can see there is a lot of information on the forum.  I have bookmarked, downloaded and read the article on the AR3a restoration, which motivated me to give all this a try.  Any and all help, comments, and advice from you guys/gals on the forum will be sincerely appreciated.

 

Regards,

 

Tmc

 

 

 

TMC, your AR-2axs were made after 1973, likely in '74, so the invoice you have would be "1975."  If you look as the clerk's sloppy handwriting, you can see that it is a "5."  AR moved from Cambridge to Norwood, Massachusetts in 1973, and your speakers are definitely Norwood models.  The label on the back does show 10 American Drive, and this would be Norwood.  Anytime you see the blue label on the back, you also know it is a Norwood-built version.  Norwood versions also had Velcro-attached grills, and your's have that feature.  These also still have the "tweeter terminal strip" (adjacent to the incorrect tweeter), and these attachment points were present on a lot of the early Norwood AR speakers.  In this case, AR had moved to back-wired tweeters, but they probably had a lot of baffle boards (the front panel that holds the speakers) with the earlier front-wired terminal strips.  This strip would not have actually been used unless these had some left-over front-wired tweeters.  In any event, it has nothing to do with the quality of the speaker!

I am pretty sure that the tweeters are the later AR-12 (or possibly AR-11) tweeters; i.e., these tweeters were used in the 1976 AR-12 if they are the 8-ohm version, or they are the AR-11/AR-10Pi versions if they are 4 ohms.  In any event, they are not correct unless a crossover adjustment has been made for them.  You should first determine the impedance, and you will need to remove one or both of them and measure the dc resistance ("dcr").  The proper dcr measurement should be in the 6-ohm range; if they measure 2.5-3.0 ohms, they are the AR-11/10Pi versions.  All of these 3/4-inch tweeters will mount in the same cutout, so it is very easy to interchange tweeters.  It is likely that these black tweeters are significantly brighter in output than the original versions, and this isn't always better.  If you can attach a close-up picture of one of the tweeters, that would be helpful.

Anyway, you have a wonderful pair of speakers, and you should definitely rebuild them as close to original as possible.  Properly working, a pair of AR-2ax speakers is very accurate and natural-sounding, and except for the last 1/3-octave of bass, they are the equal of the bigger AR bookshelf speakers in smoothness and overall sound.  Because of the 3-1/2-inch midrange cone driver, the 2ax actually images slightly better than the AR-3a and AR-5, but lacks a little of the spaciousness of the latter!  Anyway, if you do stay with the retrofitted tweeters, contact Roy C. on this site for advice on the best way to correct the crossover for the tweeters.  For the best acoustical (or "spectral") balance, you might want to try to locate some original 8-ohm AR-2ax 3/4-inch dome tweeters.  You can find either an early set of AR-2ax (or AR-5 or AR-LST/2) front-wired tweeters or a pair of later-model back-wired tweeters, and you can make them work with your cabinet either way.  Quite frankly, the early front-wired tweeters were somewhat better built, but either type will work.  Roy C can also help you get these old tweeters re-wired with new voice coils and suspensions. 

We will all help you in any way possible to get these back to their original sound!

--Tom Tyson

 

[RoyC]

1 hour ago, tysontom said:

It is likely that these black tweeters are significantly brighter in output than the original versions, and this isn't always better.  If you can attach a close-up picture of one of the tweeters, that would be helpful.

--Tom Tyson

Agreed, Tom...The tweeters are certainly brighter, and are impacting midrange frequencies as well. I believe they are the replacement tweeter sold by AB Tech in the 90's, which was recently discussed in this thread:

Roy

[Richard_C]

I see you have a Sony AV500 amp - I do as well, but also use a much older Sony FA3ES to drive my music speakers.  You also say the bass lacks something.

The AV 500 should be fine, but If you haven't done so already, check your amp setup.  By default it is set up for a 5.1 scheme with a sub woofer. so it sends a fair chunk of bass to that output and cuts bass from the other speakers.  Most people have 5 small surround speakers, not 2 nice big ones like you.. Its not clever enough to know what you are using, so you have to tell it.

Using the amp setup menu,  tell it that there is no sub woofer, and that the other speakers are large.  Then using the remote select 2CH as the output mode.  By doing that it behaves as a conventional amp and sends all frequencies to the 2 speakers you are using.

You can  still pursue all of the speaker suggestions posted here.

(if you have already done all that, sorry for repeating it but worth a check before you start spending money on speaker components)

[Tmc]

On 1/17/2019 at 10:41 PM, tysontom said:

TMC, your AR-2axs were made after 1973, likely in '74, so the invoice you have would be "1975."  If you look as the clerk's sloppy handwriting, you can see that it is a "5."  AR moved from Cambridge to Norwood, Massachusetts in 1973, and your speakers are definitely Norwood models.  The label on the back does show 10 American Drive, and this would be Norwood.  Anytime you see the blue label on the back, you also know it is a Norwood-built version.  Norwood versions also had Velcro-attached grills, and your's have that feature.  These also still have the "tweeter terminal strip" (adjacent to the incorrect tweeter), and these attachment points were present on a lot of the early Norwood AR speakers.  In this case, AR had moved to back-wired tweeters, but they probably had a lot of baffle boards (the front panel that holds the speakers) with the earlier front-wired terminal strips.  This strip would not have actually been used unless these had some left-over front-wired tweeters.  In any event, it has nothing to do with the quality of the speaker!

 

 

[Tmc]

Tom Tyson,

Thank you for an extremely informative post.  It is great to learn the history behind the speakers and see my puzzle pieces fall into place.  I managed to dig in my files yesterday and found the receipt for the repairs made in ’95.  It does not look as if the sound shop did anything to the pots or capacitors, just replaced the tweeters, woofer surrounds and dust caps. The tweeters were ordered, so it seems likely they could be the ones sold by AB Tech as referenced by Roy C. below.  (Thank you, Roy).  I would prefer to find and replace them with an original early front wired set. So, I will keep a watchful eye on E-bay and the net. I am going to look inside the cabinets this weekend with DH’s (dear husband’s ) help and post pics of what we find.

Tmc

[Tmc]

8 hours ago, Richard_C said:

I see you have a Sony AV500 amp - I do as well, but also use a much older Sony FA3ES to drive my music speakers.  You also say the bass lacks something.

The AV 500 should be fine, but If you haven't done so already, check your amp setup.  By default it is set up for a 5.1 scheme with a sub woofer. so it sends a fair chunk of bass to that output and cuts bass from the other speakers.  Most people have 5 small surround speakers, not 2 nice big ones like you.. Its not clever enough to know what you are using, so you have to tell it.

Using the amp setup menu,  tell it that there is no sub woofer, and that the other speakers are large.  Then using the remote select 2CH as the output mode.  By doing that it behaves as a conventional amp and sends all frequencies to the 2 speakers you are using.

You can  still pursue all of the speaker suggestions posted here.

(if you have already done all that, sorry for repeating it but worth a check before you start spending money on speaker components)

 

[Tmc]

Richard_C,

I did not check the amp setup menu, had no idea there was one, lol.  I originally had the speakers connected to a low end Marantz receiver.  My uncle gave my husband the Sony AV500 and he in turn gave my Marantz to his cousin.  So, I am not familiar with the Sony at all and did not even realize it came with a remote.  I’ve downloaded a manual for it and will ask my husband tonight if he has the remote and follow your suggestions.  Thanks a million.  So many helpful suggestions from the folks on this forum, a great place! 

Tmc  
 

 

[Richard_C]

If you can't find a remote don't worry, you can do it all via the buttons and selector on the unit, it just takes a bit longer.

[Aadams]

7 hours ago, Richard_C said:

If you can't find a remote don't worry, you can do it all via the buttons and selector on the unit, it just takes a bit longer.

Agree.  All the old surround receivers that I have seen have a Direct Switch or 2 Channel button or Surround on/off.  In short, it could be a button depression that solves the "bass and depth" problem.

[tysontom]

12 hours ago, Tmc said:

Tom Tyson,

Thank you for an extremely informative post.  It is great to learn the history behind the speakers and see my puzzle pieces fall into place.  I managed to dig in my files yesterday and found the receipt for the repairs made in ’95.  It does not look as if the sound shop did anything to the pots or capacitors, just replaced the tweeters, woofer surrounds and dust caps. The tweeters were ordered, so it seems likely they could be the ones sold by AB Tech as referenced by Roy C. below.  (Thank you, Roy).  I would prefer to find and replace them with an original early front wired set. So, I will keep a watchful eye on E-bay and the net. I am going to look inside the cabinets this weekend with DH’s (dear husband’s ) help and post pics of what we find.

Tmc

 

Additional thoughts on Tmc's AR-2axs:

Tweeters:

·         Measure tweeters for dc resistance with voltmeter to determine if they are the correct impedance (i.e., ≈2-4-ohm dcr would be 4-ohm version for AR-11, 10Pi; ≈5-6ohm dcr would be correct 8-ohm impedance for AR-2, AR-5, AR-12).

·         If you intend to keep the black-fabric-dome tweeters, check with Roy C about any changes made to crossover or changes that need to be made to crossover to make tweeters compatible.  The tweeter level control will need to be somewhat lower with this tweeter compared with the original, as it is about 3 dB more efficient.  Take a close-up picture of the tweeters for us to study the detail of the dome; Roy is probably correct about this being an AB Tech replacement tweeter.  I have an old, but comprehensive AB Tech part-number list on file, and I can cross-reference the tweeter if you also can find the part number on the back of it.

·         To keep the original AR-2ax "tonal balance," try to locate two original-style AR-2ax (AR-5 and AR-LST/2) 8-ohm tweeters, either front-wired or back-wired.  If the crossover had been changed by the service company in the 90s to accommodate the new black-cloth dome tweeters, be sure to return to the original crossover values.

Midrange Drivers:

·         There do not appear to be any issues with these original 3½-inch midrange drivers, and you probably don't need to do anything to them.  These were great midrange drivers, and this is one reason why the AR-2ax has such good focused-imaging properties when compared with the AR-5 or AR-3a, etc.  Much voice and music intelligibility in the AR-2ax is due to these drivers.  They don't disperse the sound as well as the AR-5 or AR-3a 1½-inch dome, and thus the AR-2ax is definitely not as 3-dimensional as the other two, but in terms of clarity and image stability, the 2ax is great.

Woofers:

·         It is possible that these woofers were the last of the yoke-magnet versions, but these could have the larger ferrite-magnet assembly.  Sometime during the 1973-1975 time frame, AR updated the earlier AR-2ax woofer (and the 8-inch woofers as well) to the new magnet assembly  Either way, the voice coils, cone materials, acoustical parameters and so forth should be very close, and the bass performance should be nearly identical.

·         The woofers will have a free-air resonance of ≈26Hz, plus-or-minus, and the AR-2ax system should have a system resonance of ≈58 Hz, plus-or-minus.  It is possible that the "refoam" job done by your service company was botched, and that the surrounds are a bit too stiff.  Remove the woofers and gently push them in to check for compliance to see if they move freely, which they should.  If they feel stiff and resistant to movement, you may have an issue with compliance; however, that is very unlikely.  Normal AR-2ax bass response will be about 3 dB down at 48 Hz, which means that you should sense relatively strong bass output down into nearly any frequency where there is music.  Bass drum and double-bass sounds come through quite clearly with the AR-2ax system, and you should be able to slightly "feel" the bass on this low-frequency output—not as strongly as with the AR-3a, of course, but not too far from it. 

·         Proper bass performance is completely dependent on where the speakers are mounted in a listening room.  The AR-2ax speakers should be mounted, either vertically or horizontally, on a shelf or stand at least one foot above the floor, against a wall.  The speaker should not be located adjacent to a large opening into another room, such as a large archway.  One speaker can be mounted in a corner.  That is, the proper flatness and extension in bass will be determined by the speakers' placement in the room, particularly when mounted up off the floor but snugly against the wall (the front wall or facing wall into your room), and better yet with perhaps one AR-2ax mounted in a corner if the room simply doesn't support bass very well.  If you pull the speakers out from the wall into the room, bass response will definitely get weaker, leaner and suffer accordingly.  It is probably best to mount the speakers along the "short" wall rather than the "long" wall of a room, as this supports bass better as well.

·         Woofer polarity is also of paramount importance.  If one woofer in one speaker is wired out of phase with the speaker in the other cabinet for some reason (service technicians sometimes don't realize this mistake), the bass will have a disjointed, diffuse sound, and low frequencies won't be properly reproduced.  To quickly check polarity of the woofers in the speaker cabinet, you should enlist the help of your husband to do the following: solder a short length of wire to each end of a type-D flashlight battery.  Remove the grill panel from the speaker, and have one person observe and the woofer.  Then, take the stripped ends of the wires and touch the positive (+) terminal battery wire to the No. 2 terminal (this is the positive input terminal) on the back of the speaker.  Observing the woofer cone, it should move out away from the cabinet.  Then do the same thing to the other speaker, and it should also do the same thing.  This way you know that the speakers have the same woofer polarity.  It is also possible that something is miswired in the crossover or the woofer leads were reversed when the tech re-foamed the woofers, but check this first.  Also, be certain that the speaker wires from the amplifier are in the proper polarity, too, such as the positive amplifier terminal is the same on both speakers.  It makes no difference if the negative connects to the No. 1 or No. 3 terminal as long as both speakers are wired the same way; however, it's always best to try to keep the positive to the positive and the negative to the negative just for neatness and clarity.

·         Be certain that the woofer is sealed properly in the cabinet.  If gaskets are used and are in good shape, you are likely sealed well for the proper acoustic-suspension seal.  Air leaks can occur at the midrange and tweeter, too, so check everything for a good acoustical seal.  The box does not have to be air-tight; this is an "acoustical seal" for the frequencies in use, not a hermitic seal, so if you gently push in on the woofer cone, it should not immediately return to the center position.  It should slowly return to the center position within about a half-second or a second.  This effect is not as pronounced on this speaker as with the larger AR-3, AR-3a, etc., but you can tell if the woofer has a good seal.

·         The fiberglass material in the speaker is likely fiberglass, not rock wool, in your version of this speaker.  You will recognize the material once you open the speaker.  Rock wool was used back in the middle 60s due to a shortage of fiberglass, and it works equally well for the purpose, but it is harder to handle.  Be certain that you have the same amount of fiberglass in both speakers, and that it is distributed pretty much the same way in both speakers.  Hopefully, the service people didn't change any of this.

Speaker Grills:

·         The replacement grill material you use appears to be dense and somewhat thick, and it may not be acoustically transparent.  The original linen grill material was dense enough to block the appearance of the drivers behind the grill, but open enough to allow sound energy to emerge without too much degradation.  If you take your grill panel and hold it up to the light, such as window light or the sun, etc., you should see at least 50% light through the grill when compared with pure light.  If it looks like the grill is blocking more than this, you should probably consider an original grill material.  AR ran out of the original beige-linen grill that was used for all AR speakers in the Cambridge era from around 1965 until 1972, and then AR went to a thicker, white-linen material that was okay but not nearly as transparent as the original.

Crossovers and Level Controls:

·         It is possible that your crossover networks are still within spec.  There is no way to know for sure other than by disconnecting one lead of each capacitor and measuring the capacitance of each capacitor and determining if it is over 15% out of spec.  The chokes (coils) are rarely out of spec, of course, unless thermally damaged somehow, and you would know this immediately.  You could, of course, go in and change all of the capacitors to be sure, but that is overreacting.  I have found many old AR speakers that had crossovers still fairly close to spec.  Also listen to your speakers to see if you detect any distortion or anything unusual in the output of the drivers.  Again, Roy C is a great resource in helping you determine what you may need to know here.

·         Level controls are the primary source of headaches in these old AR speakers.  By the time your speakers were made, AR had adopted an improved version of the Aetna-Pollock level control that had been used for so many years, and the wiper-spring tension was significantly increased.  This control is characterized by the aluminum shaft end on the back side of the speaker, and I suspect that you have this version, and that is has not been removed and replaced.  Even the improved control did not completely stop the contact issue.  If the controls still work, even if scratchy, the best thing to do would be to get some contact-cleaner spray and try to get it on the wiper surface.  To some degree, you can let it run down the shaft from the outside, but getting inside is the better way to do this.  You can also turn the control back and forth repeatedly to "clean" the contact surface if you still have fairly good electrical contact.  As a last resort, you could remove the controls and manually burnish and polish the surfaces to improve the contact.  This usually always works as long as the controls haven't been badly corroded over time due to moisture, etc.

 --Tom Tyson

[lARrybody]

If your Sony is a STR-AV500 that would be a stereo 2 channel receiver. If it is a STR-DH500 it is a 5.1 channel receiver and would have the menu mentioned above. The STR-AV500 used the RMU80 remote which there are several listed currently on the auction site for under $20.00. That is if you can't find yours.

[Tmc]

Aadams
IARrybody
Tom Tyson
Roy C
Richard C

I believe my bass problem was polarity all along.  I took another look at my speaker wire connections. The wire on the left speaker was 16 gauge dual copper wire with a white stripe along one side.  I connected the white stripe to terminal 2 (+) on the speaker and to red (+) on the receiver.  The non-striped wire went to terminal 1 (-) on the speaker and black (-) on the receiver.

The speaker wire on the right speaker was not long enough, so I found some older 18 gauge wire.  In the dim lighting of the room, it appeared to be black (oxidized) copper wire on one side and silver on the other.  So, I connected the copper wire to 2(+) on the speaker and red (+) on the receiver and the silver wire to 1 (-) on the speaker and black (-) on the receiver.  However, under better lighting, the wire was that looked like oxidized copper was actually the silver and the silver was actually the copper.  So the connections were the same from the speaker to receiver but different (I think) for each speaker.

In any event, I bought new 16 gauge copper speaker wire with a red stripe and counted the red stripe as positive on both the speakers and receiver and the non-stripe as negative.  Then I re-positioned the speakers so they were against a short wall and placed them about a foot and a half above the floor.  The bass is no longer muted, the speakers sound much better.   The receiver I have is a Sony STR-AV/500.  It is a dual channel receiver with a button to turn surround sound on or off.  I checked and “Surround” was off.

I also unscrewed the tweeters from the cabinet and looked on the backs for part numbers. Unfortunately, there were no numbers to be found.  Posted pics of the tweeters:  

http://thegoldenflower.net/AR-2ax_02.html

When we get a weekend with better weather, I will take the speakers outside and un-solder the tweeter wires to check the impedance and also look at the back of the woofers and possibly remove the stuffing and look at the capacitors and potentiometers.  I am still set on replacing the tweeters with ones original to the AR-2ax, but no luck yet finding any.   

Speaking of wire connections, found these tips on the internet (2 separate sources) which only add to the confusion:

“If correctly connected, the copper-colored wire (compared to the silver-colored wire) or the wire with the white stripe (compared to the wire with no stripe) should be your positive wire. If your amp or speaker has color-coded connections, the positive should connect to the red connection.”

“Every speaker wire will have an indicator to tell them apart, such as color. In some high-end speaker wires, the insulation is clear, or see-through, enough to see the bare wires. When this is the case, usually the silver wire will be the positive polarity and the copper wire will be negative.”  ;o)

Thanks again to all for your help.

Tmc

 

[scottie munoz]

Do the midwest tweeter replacements use ferro fluid?  The different listings they have are just marketing for different models, correct?  The 4 ohm versions are all the same....or designed for the specific model it's listed with.  Example. The 10pi tweets at midwest are sold separate listing than 3a/9 tweetsThose are the universal replacement dome tweeter sold in the 90's by AB Tech, AR's "authorized" parts and repair shop, and was the tweeter used in the AR-3a Limited sold in the Asian market in the early 90's. It is very much like the AR-11 tweeter, as well as the current AR replacement tweeter sold by Midwest Speaker. In the 3a Limited it was used with  a 4uf series cap and a .16mh parallel coil.In sept/2021..are these still the bestfeplacemebtbtweet?  Better than modified hivi?   I desperately need A 58s set and 91 set.   Hence the ferrofluid question.  Anyone have a set I could make a "large" donation for you to help me out?

Roy's done some work for me.  I'm sure he could vouch.
Lastly, can a tweet, example, the dead 91 tweet I have with no dcr reading.  Can those sti be rebuilt.   Or no dcr measured means there toast for good?  
I've heard of a fella named Chris who repairs these.  I've got quite a few and I'm not cheap.  If anyone could turn me onto his handle, is appreciate it.  

Anyone repair 12" 3way mids and/or woofers as well?

Thanks for the help.  I don't want replacements.  I'm a purist and I'd like to get my originals working and good fit a while.  Thanks again.
 

Scottie

[Aadams]

52 minutes ago, scottie munoz said:

I don't want replacements.  I'm a purist and I'd like to get my originals working and good fit a while.  Thanks again.

What price purity? Performance vs Appearance.

Consensus is:

1. The Midwest .75 tweeter is a good replacement, no mods required, for all 12 inch 3 and 4 way from 10pi  through AR58s when used in pairs. The only purist replacement for the AR3a or AR5 is a rebuilt original. 

2. No one yet rebuilds the dome midranges, but Midwest has introduced an AR9 series compatible mid-range that will work in a 58s in pairs.

3. New replacement woofers and reconed woofers are to be avoided unless there is no other option.

If cost is not a barrier contact @Chris1this1about rebuilding your broken AR91 tweeters. 

Adams