AR2ax tweeters

[troppo]

Hello Folks;

Briefly, I've been told that the replacement drivers that are available out there do not come close to the "original" AR sound. I've got my 2ax's apart and this information is a little unnerving to me. Is there any truth there ? My original tweeters are shot and I could use some advice, (Outside of rebuilding the tweeters).

Troppo

[RoyC]

Hello Folks;

Briefly, I've been told that the replacement drivers that are available out there do not come close to the "original" AR sound. I've got my 2ax's apart and this information is a little unnerving to me. Is there any truth there ? My original tweeters are shot and I could use some advice, (Outside of rebuilding the tweeters).

Troppo

It depends on which replacement drivers you are referring to. Some are better than others. The original tweeters cannot be rebuilt. The only other alternative is to find a used original pair.

Roy

[dynaco_dan]

Hello Folks;

Briefly, I've been told that the replacement drivers that are available out there do not come close to the "original" AR sound. I've got my 2ax's apart and this information is a little unnerving to me. Is there any truth there ? My original tweeters are shot and I could use some advice, (Outside of rebuilding the tweeters).

Troppo

Hi there

Roy is quite correct.

I have read more than once though that someone has repaired a 3/4" dome tweeter.

The damage was a broken lead outside of the magnet, there have been some rare successful repairs.

A steady hand and eye would certainly be required for such an intricate repair, though.

If the damage is out of sight then your tweeter is gone for good.

This is not something I have read about with the 1 3/8" dome tweeter, yet.

A repair to bring these tweeters back to life is beyond the capability of most lay people.

There is the dropin replacements available newly manufacturered, but, sounding quite differently.

Used tweeters, on ebuy, can be a source, also other brands adapted to the holes and bolt pattern, but even more different than

the original tweeters.

With 3/4" tweeters, the AR-5 and AR-LST-2's, also used the same identical 8 ohm units.

Good luck.

[soundminded]

Hello Folks;

Briefly, I've been told that the replacement drivers that are available out there do not come close to the "original" AR sound. I've got my 2ax's apart and this information is a little unnerving to me. Is there any truth there ? My original tweeters are shot and I could use some advice, (Outside of rebuilding the tweeters).

Troppo

If you are talking about the same tweeters used in AR3a and AR5 IMO this is correct. It relates to the geometry of the dome. Unlike all available tweeters made today, the dome is a full 3/4" daimeter hemisphere, projects far forward of the faceplate and there is no groove around it to act as a horn. This provides the best dispersion at the highest frequencies that a single dome can create. The only better one I'm aware of is the one Allison used which is driven inward of the dome perimeter with some sort of elastic material flexing the perimeter laterally. That tweeter's dispersion is even better. Allison in both his own models and in LST used these wide dispersion tweeters in multiples angled to obtain even greater overall system HF dispersion. IMO his concept is correct, the current concept of focused narrow dispersion to improve what is called "imaging" does not produce results nearly as realistic to the sound of acoustic instruments.

The AR2ax tweeter's shortcoming performance wise is that it does not have adequate sensitivity to match the woofer and its response rolls off somewhat. This is easily overcome with equalization and is the reason Roy Allison was able to perform his LvR demos so successfully. I was unaware of just how good this tweeter really is until a few years ago when I acquired a pair of AR2axs I restored and their tweeters seem to work perfectly with no buzzing or other distortions.

There was someone on e-bay who claimed to be able to rebuild them but I haven't seen his ads in awhile or read any reports from people who used his services. He was down the Jersey shore and charged about $40 apiece for repair service.

IMO if you don't get the treble right, nothing else about a loudspeaker system matters if it is truly intended to be high fidelity. While energy in the treble is often only a small part of what we hear and our ear's sensitivity to it isn't nearly as great as sounds of slightly lower frequency, the degree to which its amount and nature affect our perception of sound is far out of proportion to how much of it there actually is.

[dynaco_dan]

If you are talking about the same tweeters used in AR3a and AR5 IMO this is correct. It relates to the geometry of the dome. Unlike all available tweeters made today, the dome is a full 3/4" daimeter hemisphere, projects far forward of the faceplate and there is no groove around it to act as a horn. This provides the best dispersion at the highest frequencies that a single dome can create. The only better one I'm aware of is the one Allison used which is driven inward of the dome perimeter with some sort of elastic material flexing the perimeter laterally. That tweeter's dispersion is even better. Allison in both his own models and in LST used these wide dispersion tweeters in multiples angled to obtain even greater overall system HF dispersion. IMO his concept is correct, the current concept of focused narrow dispersion to improve what is called "imaging" does not produce results nearly as realistic to the sound of acoustic instruments.

The AR2ax tweeter's shortcoming performance wise is that it does not have adequate sensitivity to match the woofer and its response rolls off somewhat. This is easily overcome with equalization and is the reason Roy Allison was able to perform his LvR demos so successfully. I was unaware of just how good this tweeter really is until a few years ago when I acquired a pair of AR2axs I restored and their tweeters seem to work perfectly with no buzzing or other distortions.

There was someone on e-bay who claimed to be able to rebuild them but I haven't seen his ads in awhile or read any reports from people who used his services. He was down the Jersey shore and charged about $40 apiece for repair service.

IMO if you don't get the treble right, nothing else about a loudspeaker system matters if it is truly intended to be high fidelity. While energy in the treble is often only a small part of what we hear and our ear's sensitivity to it isn't nearly as great as sounds of slightly lower frequency, the degree to which its amount and nature affect our perception of sound is far out of proportion to how much of it there actually is.

Hi there

I did not mention the AR-3A or AR-LST tweeters because, they are physically and sonically identical, they also

both have a 4 ohm tweeter.

The Allison would be my first choice also as an alternate to an OEM AR tweeter.

My only concern, because I lack the knowledge, is not the Allison a 6 ohm tweeter rather than 8 ohms?

An adaptor plate would be needed to fit the original hole pattern.

You are very much correct in that excellent recommendation, Soundminded.

Less readily available used, sadly, but still on ebuy on rare occasion.

I would also suggest the, 1 1/2" 8 ohm Seas tweeter, as used in the Dynaco A-10, A-25, A-35 and A-50 speaker system.

These are very readily available on ebuy, but the price has risen significantly in the past few years.

I caution you and others that some uninformed sellers sell the 4 or 8 ohm Seas version of tweeters without

noting which speaker they were actually removed from.

You would want the, 8 ohm or 8 - 4 ohm version, as printed on their label, not the 4 ohm, which would perhaps be

a few db louder that an 8 ohm if compared.

The 1" tweeter used in the, Dynaco A-25XL and A-40, are 3 db more efficient, and would be too efficient without a drop in output is used.

Perhaps the AR's pot could reduce the tweeters output enough to closely match the original, in output at least.

I'm sure some other members may comment about that.

The Seas tweeter was also used in other European brand speakers, such as B&O and others.

You would need to check impedance rating of the drivers to be sure it is 8 ohms.

The Allison is probably the closest 2nd party sonic match, efficiency, power handling and dispersion wise, all four.

Without you tell us which AR tweeter you have, 3/4" or 1 3/8" we can help you more.

At least with the correct tweeter size you will have other options.

I have read here many times that there is significant differences in the later AR branded 3/4" tweeters.

There has been several tweeter variations since the original 3/4" AR OEM tweeter was discontinued back in the 1970's.

I've guessed at the decade because I truly do not know which year it was discontinued.

For example the early AR-2AX's used 1 3/8" tweeters, which were recently revealed by, Roy F Allison, formerly of AR,

as to being the same tweeter as used in the earlier AR-3 (not AR-3A) speaker which was rated at 4 ohms.

All these many years later we find that information out, I believe that, including myself, most if

not all people assumed they were 4 ohms and AR-2AX tweeters were 8 ohms, when in fact there are the same tweeters.

Soundminded as a side note when you mentioned earlier and elsewhere about all the tweeters you have I was overwhelmed and wanted to

come back with a funny.

You have taken my breath away and I still can't dream up a funny response yet.

I would have loved to have had some for experimenting with over the years.

Perhaps making up some Microstatic tweeter arrays, Janszen 1-30 electrostatic tweeter arrays or similar to RTR-15 electrostatic tweeter style arrays.

Or just hang some from the branches of a Christmas tree. LOL

[soundminded]

Hi there

I did not mention the AR-3A or AR-LST tweeters because, they are physically and sonically identical, they also

both have a 4 ohm tweeter.

The Allison would be my first choice also as an alternate to an OEM AR tweeter.

My only concern, because I lack the knowledge, is not the Allison a 6 ohm tweeter rather than 8 ohms?

An adaptor plate would be needed to fit the original hole pattern.

You are very much correct in that excellent recommendation, Soundminded.

Less readily available used, sadly, but still on ebuy on rare occasion.

I would also suggest the, 1 1/2" 8 ohm Seas tweeter, as used in the Dynaco A-10, A-25, A-35 and A-50 speaker system.

These are very readily available on ebuy, but the price has risen significantly in the past few years.

I caution you and others that some uninformed sellers sell the 4 or 8 ohm Seas version of tweeters without

noting which speaker they were actually removed from.

You would want the, 8 ohm or 8 - 4 ohm version, as printed on their label, not the 4 ohm, which would perhaps be

a few db louder that an 8 ohm if compared.

The 1" tweeter used in the, Dynaco A-25XL and A-40, are 3 db more efficient, and would be too efficient without a drop in output is used.

Perhaps the AR's pot could reduce the tweeters output enough to closely match the original, in output at least.

I'm sure some other members may comment about that.

The Seas tweeter was also used in other European brand speakers, such as B&O and others.

You would need to check impedance rating of the drivers to be sure it is 8 ohms.

The Allison is probably the closest 2nd party sonic match, efficiency, power handling and dispersion wise, all four.

Without you tell us which AR tweeter you have, 3/4" or 1 3/8" we can help you more.

At least with the correct tweeter size you will have other options.

I have read here many times that there is significant differences in the later AR branded 3/4" tweeters.

There has been several tweeter variations since the original 3/4" AR OEM tweeter was discontinued back in the 1970's.

I've guessed at the decade because I truly do not know which year it was discontinued.

For example the early AR-2AX's used 1 3/8" tweeters, which were recently revealed by, Roy F Allison, formerly of AR,

as to being the same tweeter as used in the earlier AR-3 (not AR-3A) speaker which was rated at 4 ohms.

All these many years later we find that information out, I believe that, including myself, most if

not all people assumed they were 4 ohms and AR-2AX tweeters were 8 ohms, when in fact there are the same tweeters.

Soundminded as a side note when you mentioned earlier and elsewhere about all the tweeters you have I was overwhelmed and wanted to

come back with a funny.

You have taken my breath away and I still can't dream up a funny response yet.

I would have loved to have had some for experimenting with over the years.

Perhaps making up some Microstatic tweeter arrays, Janszen 1-30 electrostatic tweeter arrays or similar to RTR-15 electrostatic tweeter style arrays.

Or just hang some from the branches of a Christmas tree. LOL

Since the smaller the tweeter the better the dispersion, I'd try a 3/8" mylar (polypropylene) dome such as an Audax. The ones I bought are similar. I've paid as much as $8 and as little as 5 cents. You can cross them over at 6khz with a simple 3.3 ufd NPC and they are quite forgiving of a first order filter. They are also cheap. Sensitivity is very good, about 90db. I'd also try one of the Peerless India 1" domes without a face plate if Parts Express still has any. They were about $4. From the look of them in their sales flyers a few months ago, the dome projects out quite a bit. If you find any of these tweeters too bright, you can always put a 1 or 2 ufd cap across the voice coil to roll off their high end.

[dynaco_dan]

Since the smaller the tweeter the better the dispersion, I'd try a 3/8" mylar (polypropylene) dome such as an Audax. The ones I bought are similar. I've paid as much as $8 and as little as 5 cents. You can cross them over at 6khz with a simple 3.3 ufd NPC and they are quite forgiving of a first order filter. They are also cheap. Sensitivity is very good, about 90db. I'd also try one of the Peerless India 1" domes without a face plate if Parts Express still has any. They were about $4. From the look of them in their sales flyers a few months ago, the dome projects out quite a bit. If you find any of these tweeters too bright, you can always put a 1 or 2 ufd cap across the voice coil to roll off their high end.

Hi there

Thank you for the tweeter and capacitor tips, Soundminded.

Was the 5 cents with taxes? LOL

I once tried to make an AR-LST using Dynaco woofers and tweeters.

Didn't work out too well as I remember.

I also tried to make a pair of Microstatic style tweeter array with Dynaco tweeters.

Didn't work out as well as I remember.

Cabinet making was not one of my skills, not that I had many.

I should have based my LST's on A-50 components, dual woofers, and cabinet construction,rather that the A-25's cabinet size.

A single woofer's output was not strong enough with the 4 tweeters in one cabinet, as I remember.

The 4 tweeter only array enclosure had a pot, switch and dual caps.

I could switch in or out the same as A-25 or A-35 crossover points at will.

I see the crossover only board still near my bed after all these years.

The tweeter was the much stronger, as in power handling, of the two drivers, no doubt.

[deek]

While it's a more modern driver and probably wouldn't fit the hole, etc... I wonder how the tweeter from the AR17/18 would work? It's a dome/horn type as well and sounds quite nice in a 2-way system.

-Deek

[JKent]

Hi Troppo and welcome to the CSP

I'm away from home but had access to a computer and had to comment.

First--are you SURE the tweeters are shot and not just the pots and/or caps?

Second--It is true that new tweeters will not sound exactly like your original AR2ax tweets, but Roy worked out a very simple and inexpensive mod for the AR3a, using HiVi Q1R tweets and parallel inductors. See this thread and also search for HiVi Q1R in the AR section:

http://www.classicsp...h=1

I used the HiVi tweeters in my AR3a's and am very happy with the results. I believe they should also work in the 2ax, but maybe Roy will comment.

Good luck.

Kent

[soundminded]

Hi there

Thank you for the tweeter and capacitor tips, Soundminded.

Was the 5 cents with taxes? LOL

I once tried to make an AR-LST using Dynaco woofers and tweeters.

Didn't work out too well as I remember.

I also tried to make a pair of Microstatic style tweeter array with Dynaco tweeters.

Didn't work out as well as I remember.

Cabinet making was not one of my skills, not that I had many.

I should have based my LST's on A-50 components, dual woofers, and cabinet construction,rather that the A-25's cabinet size.

A single woofer's output was not strong enough with the 4 tweeters in one cabinet, as I remember.

The 4 tweeter only array enclosure had a pot, switch and dual caps.

I could switch in or out the same as A-25 or A-35 crossover points at will.

I see the crossover only board still near my bed after all these years.

The tweeter was the much stronger, as in power handling, of the two drivers, no doubt.

Parts Express offered a box of 200 for $10. I bought 2 boxes. No shipping cost, I don't think there was any tax either.

The design intent is clearly for the widest dispersion possible. The phase plug in front of the center of the dome improves dispersion. The versions I've seen range from 3/8 to 3/4 inch, some with 30 watts capacity. The 5 cent versins are small enough to experiment with very closely spaced arrays to reduce comb filtering which is said to be inaudible anyway.

Since the Woofer consumes most of the power and you shouldn't put a potentiometer or L-pad in series with it, if you are not going to multi-amp it, it should be the least efficient (sensitive) driver in the system. The other dirvers are padded down to suitable levels to match it. FR is easily controllable in a number of ways from active equalization to passive filter (crossover network) design. Usually the best results including by professional designers is obtained through trial and error. The calculations are just a starting point, most designs deviate from true Butterworth, Linkwitz-Riley or other textbook formulas. Often they deviate considerably.

[dynaco_dan]

Parts Express offered a box of 200 for $10. I bought 2 boxes. No shipping cost, I don't think there was any tax either.

The design intent is clearly for the widest dispersion possible. The phase plug in front of the center of the dome improves dispersion. The versions I've seen range from 3/8 to 3/4 inch, some with 30 watts capacity. The 5 cent versins are small enough to experiment with very closely spaced arrays to reduce comb filtering which is said to be inaudible anyway.

Since the Woofer consumes most of the power and you shouldn't put a potentiometer or L-pad in series with it, if you are not going to multi-amp it, it should be the least efficient (sensitive) driver in the system. The other dirvers are padded down to suitable levels to match it. FR is easily controllable in a number of ways from active equalization to passive filter (crossover network) design. Usually the best results including by professional designers is obtained through trial and error. The calculations are just a starting point, most designs deviate from true Butterworth, Linkwitz-Riley or other textbook formulas. Often they deviate considerably.

Hi there

I was laughing at your 5 cent tweeters this morning, Soundminded.

We can't even buy a jelly bean, red licorice, bubble gum or jaw breakers for 5 cents today.

You truly got yourself a real bargain.

[soundminded]

Hi there

I was laughing at your 5 cent tweeters this morning, Soundminded.

We can't even buy a jelly bean, red licorice, bubble gum or jaw breakers for 5 cents today.

You truly got yourself a real bargain.

If you think that's a bargain, consider that I only paid $500 for my pair of AR9s as store demos. AR replaced all of the drivers before I took delivery because the dust caps had been pushed in. I paid $0 for my pair of AR2axs and AR2as which were rescued from going to the trash. Also for a pair of KLH Model 6s, 3 Empire 9000s (without the marble tops), a pair of Electrovoice Wolverines, and a pair of 3 cu ft JBL 15 foot subwoofer enclosures. I think only one of the Wolverines had a driver.

I've gotten lots of deal. I bought about 50 drivers for $50 from a Radio Shack manager who ordered them for someone who never paid for them or collected them. Four of them are Tonegen ribbon tweeters. Two were 8" Fostex 8" drivers. I've gotten lots of other great deals too. Example, Pioneer SX950 Receiver in mint condition at a garage sale for $10. I'm always on the lookout for bargains.