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3a tweeters


HarryM

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I picked up a pair of 3a's that don't have the original tweeters so I am on the look out for some.My question is if the dome is pushed in are they repairable.

I really would like to get these back to what they should be but I have managed to improve the sound with the tweeters that are in them.At least I can listen to them now with out my ears splitting.LOL.Thanks Roy for your post about changing the 6uf cap to a 2uf cap for the HiVi tweeters or was it the ABTech tweeters,I can't remember that part.I tried that with these and it help alot.

I did find it interesting that the mid range driver produces most of the sound.At least on mine,I hope thats normal or I have a lot more work to do.

Thanks for anything anybody can tell me.Harry.

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vintage ar has brand new ones for sale, try them

Nobody is selling brand new original AR tweeters. Larry is selling HiVi and AB Tech replacement tweeters.

Harry....The pushed in tweeter can be used as is. Some people have managed to pull dents out of the domes by wetting them, and the use of suction of a vacuum cleaner. The midrange driver does produce much more sound. This is normal.

There are a couple of approaches to take with the HiVi and ABT tweeters. The preferable way to start is not a 2uf replacement cap, but to simply add a .05mh parallel inductor to either of these tweeters. Larry/Vintage AR does sell the HiVi tweeters already set up with the inductor. The parts to do it yourself are also readily available from Parts Express and Madisound..

Roy

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Here is a photo of the Hi-Vi tweeter mod, with the inductor mounted to the back of the tweet. I added a 6uF cap in series with the xo's 6uF, making the tweeter cap 3uF, which raises the crossover point. The tweeter in the 3a is more of a "super tweeter" but the Hi-Vi tweeter reproduces more of the upper mid/lower high frequencies than the original tweeter. On Roy's advice, I added the additional 6uF after the fact so I just pulled the tweet and added the cap. The blue thing is a Vishay-Roederstein "bypass": highly regarded by some but IMHO it does nothing.

You could do as Roy suggested and just add the Hi-Vi plus inductor. If you want to experiment down the road, add the 2nd 6uF cap as I did, by simply pulling the tweet.

Kent

post-101828-0-21865500-1345648040_thumb.

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Thanks for all the info everybody.Since I still need to contact Larry at Vintage AR about Roy's goop fo my 4x woofers,I'll order a pair of HiVi's with inducters as well and keep looking for originals.Anybody need a pair of made in Norway tweeters that can split your eardrums.LOL

Thanks,Harry

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  • 4 months later...

I thought I would update this thread.

I never did order the HiVi's but I picked up a pair of donor 3a's that had original tweeters and mids. The woofers are not original. I just finished installing the tweeters into my first pair and even though they are only hooked up to a tape deck and an older 30 watt per channel technics stereo they sound very good. They are not an in your face speaker. A nice laid back sound, strong but relaxing,comfortable even. How's that for technical terms.

Harry.

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  • 3 weeks later...

I picked up a pair of 3a's that don't have the original tweeters so I am on the look out for some.

Thanks for anything anybody can tell me.Harry.

Does anyone know a decent AR3a/AR11/AR10pi replacement tweeter (besides the one from AB Tech) ? I have received a very bad pair of AR10pi cabinets without speaker units. Is it possible to use the AR2AX tweeters as replacement in the AR10pi's?

Thanks in advance

Kim

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Hi Kim

The AR-2AX, AR-5 and AR-LST/2 used a 3/4" 8 ohm tweeter, not 4 ohm.

If 8 ohm is used in a 4 ohm system, it will work, but the tweeter sound level will be at a very much reduced output level, measureable and audible.

Visually an easy mistake to do with them having identical physical characteristics.

Audibly a failure.

The reverse substitution may work, subbing a 8 ohm with a 4 ohm driver, but the higher output level will need taming, perhaps.

My thought for today.

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Hi Kim

The AR-2AX, AR-5 and AR-LST/2 used a 3/4" 8 ohm tweeter, not 4 ohm.

If 8 ohm is used in a 4 ohm system, it will work, but the tweeter sound level will be at a very much reduced output level, measureable and audible.

Hi Dan,

I did'nt know the AR-2AX used a 8 Ohm tweeter. As you know it's difficult to find original tweeters for the AR10pi. The AR11 tweeters looks like the AR10pi's, but still ...they are also hard to find in fair condition.

I have a burned original tweeter, and I have tried to measure the coil size and wire thickness...it's not an easy job to replace the coil and the three "glue dot's"....which type of flexible glue was used? I might be able to find the right wire-thickness and wound the coil on a captan....but don't know anything about AR's tolerance and clearance between the coil and pole-piece?

Rgds. Kim

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Anybody need a pair of made in Norway tweeters that can split your eardrums.LOL

Harry,

Those would be SEAS tweeters and although not right for the 3a they are probably excellent. Maybe you can determine the model #.

Does anyone know a decent AR3a/AR11/AR10pi replacement tweeter (besides the one from AB Tech) ?

Kim,

RoyC's HiVi tweeter mod for the AR-3a is well documented here. They are inexpensive on this side of the pond (I think they are Swan in Europe). Just add an inductor and you're good to go.

Kent

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The approach to the AR-10pi and AR-11 is different than the early models (3a, 2ax, 5, etc). The tweeters were different, as well as the crossovers. As Kent mentioned above the HiVi Q1R works fairly well in the 3a (as well as all of the early models) with a crossover modification.

The best replacement for later models such as the AR-11 and 10pi is probably the AB Tech tweeter as sold by Vintage AR. He is adding some damping material under the dome to modify its response. You can also try the HiVi X1, which will fit the hole, and is inexpensive. http://www.parts-express.com/pe/showdetl.cfm?partnumber=297-418.

The X1 is a sleeper in the scheme of things considering the cost, but the faceplate does not look like anything AR.

No parallel coils are needed, as there are .1mh parallel coils already in the crossovers of the AR-10pi/11, but a 25% to 50% reduction of the 10uf tweeter cap value will bring you closer to the original sound with the replacement tweeters mentioned above.

No tweeter will sound exactly the same as the original, and there are no "drop in" replacements.

Roy

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Harry,

Those would be SEAS tweeters and although not right for the 3a they are probably excellent. Maybe you can determine the model #.

Kent

The #'s are 25TF, H456, 60HM, 1S/90. Now that I have correct tweeters in my 3a's these tweeters will sit until I happen to find a use for them. I am glad that I managed to get correct tweeters for my 3a's because they sound very good.

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They are "SEAS VINTAGE PRESTIGE TWEETERS". It's an older model. 25 is the voice coil size.

Here's the spec sheet

http://www.seas.no/images/stories/vintage/pdfdataheet/h0456_25tf.pdf

btw--Roy's link to the HiVi tweeter doesn't work Try this: http://www.parts-express.com/pe/showdetl.cfm?partnumber=297-418

and here are Swan dealers in Europe: http://www.swanspeaker.com/dealers/dealers.aspx#5

Kent

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Kent

The #'s are 25TF, H456, 60HM, 1S/90. Now that I have correct tweeters in my 3a's these tweeters will sit until I happen to find a use for them. I am glad that I managed to get correct tweeters for my 3a's because they sound very good.

Hi there

As we can read, the voice coil is a rated nominal 6 ohms, not the more common 4 or 8 ohms of old.

If used in an older AR-3A system the tweeter output will be slightly down in output level compared with the original tweeter, which we likely can tolerate.

If used with the older AR-2AX/AR-5 etc the tweeter output will be slightly higher than the original tweeter, which we can also adjust.

The output capabilities, transparency, dispersion, power handling capabilities and frequency response may be different but I do not think anyone here can hear the differences, at least NOT ME.

.It does give a decent option at least.

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Thanks for fixing the link, Kent...

The Seas tweeter is an excellent tweeter, but would need a crossover adjustment of the type discussed above to have any chance of being acceptable inan old AR speaker. The replacement tweeters discussed above would not sound right without these adjustments as well.

Vern, given the differences in modern construction, and the use of ferro fluid, etc, the "rated" impedance of potential replacement tweeters is not as relevant as you may think. The HiVi Q1R is a "6 ohm" tweeter and works well in the 3a. Crossover modifications and level controls are what make them acceptable...as long as they have enough sensitivity. Rated impedance is not the primary parameter to take into consideration. I agree, however, that the early 8 ohm AR 3/4" dome tweeter would make a very poor replacement for it's 4 ohm counterpart in the 3a....

Roy

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The approach to the AR-10pi and AR-11 is different than the early models (3a, 2ax, 5, etc). The tweeters were different, as well as the crossovers. As Kent mentioned above the HiVi Q1R works fairly well in the 3a (as well as all of the early models) with a crossover modification.

The best replacement for later models such as the AR-11 and 10pi is probably the AB Tech tweeter as sold by Vintage AR. He is adding some damping material under the dome to modify its response. You can also try the HiVi X1, which will fit the hole, and is inexpensive.

The X1 is a sleeper in the scheme of things considering the cost, but the faceplate does not look like anything AR.

No parallel coils are needed, as there are .1mh parallel coils already in the crossovers of the AR-10pi/11, but a 25% to 50% reduction of the 10uf tweeter cap value will bring you closer to the original sound with the replacement tweeters mentioned above.

No tweeter will sound exactly the same as the original, and there are no "drop in" replacements.

Roy

Hi Roy,

Your statement : " ...and there are no "drop in" replacements." .....was what I had in mind. I have searched for a tweeter with a diameter of 120 mm or approx. 4"12/16. The frontplate size was one problem. The issue for all of us (besides that I like the original AR look), is the sonic sound of the tweeter.

The mentioned HiVi Q1R with the (almost) flat frontplate seems to be a fair replacement in A3's, as far as the reviewers recommend the tweeter.

I have erlier bought the replacement midrange dome from AB Tech, and the magnet "engine" are quite smaller for that unit than the original AR midrange. The smaller magnet engine provides a somewhat lower output. I have never seen the replacement tweeter from AB Tech, and I wonder whether the output is similar to the AR10pi and AR11 tweters?

Who is "Vintage AR" and "he" ? Do you have a link?

The original AR3a tweeters had a kind of light brown foam damping material under the dome , but I have never taken a AR11 tweeter apart , and consequently, I do not know whether the AR11 tweeter also has the same damping foam below the textile membrane.

The HiVi X1 has a kind of "horn-like" shape around the fabric dome which increases the output. The fundamental idea with the tweeters from AR3a and foreward was the flat frontplate and only the 3/4 inch dome lifted above the groundplane. According to measurements this placement of the dome results in a very good dispersion of high frequencies. I have therefore searched for a tweeter with these characteristics.

One possibillity are the Dynaudio D28/2 with ferrofluid or Esotec because they sound much like the original ...but again small face plate :

the three w's and gattiweb.com/dynaudio.htm

From Audax: the three w's and madisoundspeakerstore.com/audax-soft-dome-tweeters/audax-tw025a2-1-textile-dome-tweeter-4-ohm-by-aac/

I need to work and find a better solution.

Rgds. Kim

Ps. why is it not allowed to show link's at this forum??

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Vintage AR is a reliable (but sometimes expensive) supplier of AR parts. Links are permitted. Here's one to Vintage AR:

http://stores.ebay.com/VINTAGE-AR-PARTS-AND-SERVICE

btw--I bought a pair of theAudax TW025A2 1" Textile Dome Tweeter, 4 ohm that you mentioned because they were recommended as possible replacements for Allison{ Four tweeters. So the lineage is there, but I have no idea if they would work in the 3a. Faceplate is too small for one thing.

Kent

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Hi Kim,

I've been working on this issue for a very long time. You will not find a drop-in modern replacement. The AB Tech tweeter, with some modifications, will be as close as you are likely to get. The AR-3a era tweeters were very unique, and no modern tweeter can match it without some kind of modification work. Btw, dispersion is another matter, and much harder to match. I have, however, not found it to be a significant issue.

The material under the dome of the 3a type tweeter is the same type of foam used for the suspension, which is mostly turning to dust these days.

The AR-11 dome has a wooden plug under it. I did some experimenting, and discovered a similar wooden plug (and some felt) diminished the harshness of the AB Tech tweeter, and shared this info with Vintage AR...who is now performing this modification. The 3/4" ABT tweeter fits the hole very well, and has a comparable magnet to the original AR tweeter. It also has more output than the 3a and the AR-11/10pi tweeter. Even with the modification to the ABT tweeter, crossover changes are still needed to bring it sonically closer to the original tweeter (if the goal is to get as close as possible). It works fairly well in the AR-11, but a cap value reduction will make it better. In the AR-3a, a .05mh parallel coil is absolutely required.

Roy

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Hi Kim,

The AB Tech tweeter, with some modifications, will be as close as you are likely to get. Btw, dispersion is another matter, and much harder to match. I have, however, not found it to be a significant issue.

The material under the dome of the 3a type tweeter is the same type of foam used for the suspension, which is mostly turning to dust these days.

The AR-11 dome has a wooden plug under it. I did some experimenting, and discovered a similar wooden plug (and some felt) diminished the harshness of the AB Tech tweeter, and shared this info with Vintage AR...who is now performing this modification. The 3/4" ABT tweeter fits the hole very well, and has a comparable magnet to the original AR tweeter. It also has more output than the 3a and the AR-11/10pi tweeter. Even with the modification to the ABT tweeter, crossover changes are still needed to bring it sonically closer to the original tweeter (if the goal is to get as close as possible). It works fairly well in the AR-11, but a cap value reduction will make it better. In the AR-3a, a .05mh parallel coil is absolutely required.

Roy

Hi Roy,

I understand that you have been working with this tweeter issue for a long time. The AB Tech tweeter seems to be a good replacement and close to the visual look of AR10pi/11.

I agree with you that the foam material under the A3 dome has crumbled into dust, which bring me to ask:

How did you manage to place a wooden plug under the 3/4" AB Tech dome? Is it possible to disassemble the frontplate and remove the dome and voicecoil on the AB Tech dome?

You were not really satisfied with the sonic sound of the AB Tech tweeter....you wrote : "to diminish the harshness of the AB Tech tweeter sound". Others have tried with magnetic oil to reduce frequence spikes like Epicure's inverted dome ...which sounds good.....but we can't implement that dome in a AR speaker, no we can't :-) :-)

The experimental listening tests that AR made back then could have been the foam or the wooden plug under the dome as a solution to reduce some high frequence spikes? We don't know that for sure...what we all know are the fact that most dome tweeters has some harshness if the crossover frequence cut off or even the dome design is wrong or not optimized.

As mentioned by Kent the Audax TW025A2 1" Textile Dome Tweeter, 4 ohm has a good reputation and is inexpensive....I could try the sound in my AR11. If the Audax tweeter works well in AR11, then why not try it in AR10pi.

Roy , regarding sound....do you have the opinion from others who has listened the AB Tech modified 3/4" tweeter in AR10pi or AR11?

Best rgds.

Kim

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Hi Kim

Right now there are two original AR-11/10Pi tweeters for sale on German ebay, not cheap but apparently in working condition.

BRgds Klaus

Hi Klaus,

Thanks for the link. I have checked the Tweeters at ebay.de with green checkered surface layer.

Is that standard surface for AR11 tweeters?

Best rgds

Kim

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Hi Roy,

I understand that you have been working with this tweeter issue for a long time. The AB Tech tweeter seems to be a good replacement and close to the visual look of AR10pi/11.

I agree with you that the foam material under the A3 dome has crumbled into dust, which bring me to ask:

How did you manage to place a wooden plug under the 3/4" AB Tech dome? Is it possible to disassemble the frontplate and remove the dome and voicecoil on the AB Tech dome?

You were not really satisfied with the sonic sound of the AB Tech tweeter....you wrote : "to diminish the harshness of the AB Tech tweeter sound". Others have tried with magnetic oil to reduce frequence spikes like Epicure's inverted dome ...which sounds good.....but we can't implement that dome in a AR speaker, no we can't :-) :-)

The experimental listening tests that AR made back then could have been the foam or the wooden plug under the dome as a solution to reduce some high frequence spikes? We don't know that for sure...what we all know are the fact that most dome tweeters has some harshness if the crossover frequence cut off or even the dome design is wrong or not optimized.

As mentioned by Kent the Audax TW025A2 1" Textile Dome Tweeter, 4 ohm has a good reputation and is inexpensive....I could try the sound in my AR11. If the Audax tweeter works well in AR11, then why not try it in AR10pi.

Roy , regarding sound....do you have the opinion from others who has listened the AB Tech modified 3/4" tweeter in AR10pi or AR11?

Best rgds.

Kim

Kim,

The general opinion, including my own, until now has been that the ABT tweeter is too costly, and somewhat harsh sounding. AR, and most modern tweeters, usually have something under the dome for damping, so I decided to modify the ABT tweeter after realizing the dome/voice coil assembly is easily removed...and finding nothing under the dome. The added material improves it to the degree that I now believe it is a viable option, especially since it fits the cabinet so well...but it is still costly. The best replacement for the 10pi remains the original AR 3/4" tweeter of the AR-11/10pi era.

The answer to your original question (Does anyone know a decent AR3a/AR11/AR10pi replacement tweeter) will always be that there can never be a single "universal" AR replacement tweeter for the AR-11/10pi AND AR-3a without crossover modifications. They are different designs with different tweeters. When AR began using the AR-11 tweeter as a 3a replacement, it was supplied with a series cap glued to the back of it to compensate for the difference. The good news is that your missing AR-10pi/AR-11 type tweeter is less "unique" than the AR-3a and 2ax type of tweeter, and modern options have a better chance of working out as replacements.

Roy

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  • 3 weeks later...

Hi Roy (since this pertains to the penultimate sentence in your last post here),

You mention the AR sub of the AR-11 tweeter in 3as and the factory's fitting of a series cap - do you recall/know the value and what, if any, other modifications were made? I ask because I found a couple of NOS replacement 11 tweeters and wish to fit them to one pair of my AR-3as.

Thanks, John

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