ar 2ax tweeter replacement options

[jims]

I found this site while trying to find a replacement tweeter for my 1973 era 2ax's (s/n in the 201,000 and 204,000) and was surprised to see how many others have appreciated the AR brand. As with most of those posting here, I have found I need the whole menu of restoration-woofer refoaming, pots and a shot voice coil in a tweeter. I am having my repair tech do the work as this is beyond my abilities. The woofer work and replacing the pots with the L-pad seems to be a given, and would hope for some advice from the pros here on the tweeter. It seems the options are:

1. Find an original. My tech and I have not had any success here.

2. Acquire them from AB Tech, Vintage Ar, or Simply Sound (linked via a reference here to Layne). Are these the same tweeter, just from differenct vendors?

3. Use the HiVi from Parts Express.

The HiVi seems to have alot of positive responses from RoyC and JKent who seem to have done several of these. I am like most others here and want to preserve the original sound as much as possible and am curious what the forum members think about these choices. Also, my tech and I have the following "questions":

From what I can tell, there is nothing wrong as such with the AB or Vintage tweeters, mainly cost-$60 to 70 versus $23?

Is the HiVi pretty much a drop in replacement or does it require alot of modifications as compared to the others, as this may affect the cost difference in labor versus material? It appears the others are a drop in.

JKent gave a parts list for the HiVi in a 6/4/11 post under ar2ax smoked pots and tweeter dome. Is this everything for the tweeter and L-pads?

I see some discussion on modifying the crossover for the HiVi. Is this necessary for the AB or Vintage tweeter?

On an old post from 12/18/08 (tweeters nonfunctional) JKent is quoting RoyC re the HiVi and discussing crossover mods, and reversing polarity. Is this covered in the A3 restoration manual (I have printed for my tech) or is this useful to provide him as well.

As I told my tech, I like him alot as he has done wonders for my other vintage equipment yet if it comes down to paying more for parts or alot more for extensive labor to go the HiVi route, then it would be helpful to know.

Any education/feedback would be most welcome.

As a sidenote, I mentioned my AR turntable and he thought there is strong interest in these. It is a YP-701 from around 1977. I do not recall it being top of the line, although I usually purchased decent quality components. It is in great shape and in the original box.

Also, thanks to whomever is maintaining this great site.

[JKent]

Hi Jims (Jim S?) and welcome

Roy is the expert on this. I'm just a follower. But maybe I can answer a couple of questions based on what he's taught me.

Much of the work done by Roy has come since publication of the AR3a restoration manual (he was one of the authors) so it is not included there. To address some specifics:

1. The old AR tweeters are nearing the end of their lifespans, so even if you find some they may not last long. The foam suspensions tend to "pop".
2. The Vintage-AR speaker is the Hi-Vi with a .05mH inductor. It is not the same as the others you mentioned. The AB Tech tweeter needs modification and costs more. The Simply Speakers tweet is # 12000840 so seems to be the same as AB Tech. Layne is defunct.
3. The Hi-Vi (with an inductor) is a very good replacement. Virtually a drop-in.

The Hi-Vi is not a perfect match for the original, but it works well. Roy continues to experiment with tweeters and crossover mods (nothing major--a cap here, a resistor there). In fact I just made a slight mod to the Hi-Vi's in my 3a's today, based on a personal communication with him. I'll leave it to him to post any of his latest work when he chooses to do so. It's a "work in progress" and you can bet no one else is putting in the time and effort for this "niche market." btw--that tweeter from Vintage AR is 100% Roy's work. Vintage AR takes a $22 tweeter and a $3 inductor, sticks them together as Roy taught him, and sells it for what? $60? And I know Roy gets no cut from that. He's an avid and generous hobbyist who freely shares the fruits of his labors. Then Vintage AR turns a profit on it.

The only thing you need to do to the Hi-Vi tweeter is attach an inductor in parallel. Just glue it to the back of the tweet. You do need to reverse polarity due to the inductor. However, some stock 2ax's had the tweeter polarity reversed, in which case you would not reverse (does that make sense? Roy can probably determine if the leads should be reversed or not based on the dates 1973 era and s/n between 201,000 and 204,000. Or do it by ear to determine which sounds better). There has been some discussion of adding a resistor in series, but I "think" that is not really necessary. Roy can advise on that too.

The AB Tech tweet must be modified as described in the 3a manual. The Hi-Vi must be "modded" (inductor added). The Vintage-AR version comes with inductor but you pay for that.

My advice is to go with the Hi-Vi plus inductor.

Buy L-Pads from Parts Express along with the 25 ohm 10 watt resistors as described on pp 14-15 of the 3a manual. I believe the parts list I gave in this link is complete, but Roy may have suggestions to add or change something http://www.classicsp...h=1

One final note: The 2ax did not use the same tweeter as the 3a. Roy's work with the Hi-Vi tweeter has been mainly aimed at finding a replacement for the 3a. It is also a good replacement for the 2ax as I understand it, but the 2ax is different.

AFAIK, AR made the XA, XB and ES-1 TT but not the YP-701. That's a Yamaha.

Good luck and come back with more questions.

Kent

[michiganpat]

Hi Jims (Jim S?) and welcome

Roy is the expert on this. I'm just a follower. But maybe I can answer a couple of questions based on what he's taught me.

Much of the work done by Roy has come since publication of the AR3a restoration manual (he was one of the authors) so it is not included there. To address some specifics:

1. The old AR tweeters are nearing the end of their lifespans, so even if you find some they may not last long. The foam suspensions tend to "pop".
2. The Vintage-AR speaker is the Hi-Vi with a .05mH inductor. It is not the same as the others you mentioned. The AB Tech tweeter needs modification and costs more. The Simply Speakers tweet is # 12000840 so seems to be the same as AB Tech. Layne is defunct.
3. The Hi-Vi (with an inductor) is a very good replacement. Virtually a drop-in.

The Hi-Vi is not a perfect match for the original, but it works well. Roy continues to experiment with tweeters and crossover mods (nothing major--a cap here, a resistor there). In fact I just made a slight mod to the Hi-Vi's in my 3a's today, based on a personal communication with him. I'll leave it to him to post any of his latest work when he chooses to do so. It's a "work in progress" and you can bet no one else is putting in the time and effort for this "niche market." btw--that tweeter from Vintage AR is 100% Roy's work. Vintage AR takes a $22 tweeter and a $3 inductor, sticks them together as Roy taught him, and sells it for what? $60? And I know Roy gets no cut from that. He's an avid and generous hobbyist who freely shares the fruits of his labors. Then Vintage AR turns a profit on it.

The only thing you need to do to the Hi-Vi tweeter is attach an inductor in parallel. Just glue it to the back of the tweet. You do need to reverse polarity due to the inductor. However, some stock 2ax's had the tweeter polarity reversed, in which case you would not reverse (does that make sense? Roy can probably determine if the leads should be reversed or not based on the dates 1973 era and s/n between 201,000 and 204,000. Or do it by ear to determine which sounds better). There has been some discussion of adding a resistor in series, but I "think" that is not really necessary. Roy can advise on that too.

The AB Tech tweet must be modified as described in the 3a manual. The Hi-Vi must be "modded" (inductor added). The Vintage-AR version comes with inductor but you pay for that.

My advice is to go with the Hi-Vi plus inductor.

Buy L-Pads from Parts Express along with the 25 ohm 10 watt resistors as described on pp 14-15 of the 3a manual. I believe the parts list I gave in this link is complete, but Roy may have suggestions to add or change something http://www.classicsp...h=1

One final note: The 2ax did not use the same tweeter as the 3a. Roy's work with the Hi-Vi tweeter has been mainly aimed at finding a replacement for the 3a. It is also a good replacement for the 2ax as I understand it, but the 2ax is different.

AFAIK, AR made the XA, XB and ES-1 TT but not the YP-701. That's a Yamaha.

Good luck and come back with more questions.

Kent

you covered most of it Jkent. the AB tech replacement is a physical direct fit, but does not match the originals sonically in any way. hopefully RoyC chimes in, IIRC his recommendation for the 2ax was the hivi, but a slightly different inductance value (I want to say something like a .07mh) for the 2ax.

as an aside, maybe someone could contact MISCO http://www.miscospeakers.com/ and see how much it would be to reverse engineer and build reproductions of some of the different AR drivers (maybe a replacement 8", 10", truncated frame 12" and the 3/4" tweeter? they already make a reproduction of the boston acoustics A60 series 1 woofer sold by Midwest Speaker...

[RoyC]

1. Find an original. My tech and I have not had any success here.

2. Acquire them from AB Tech, Vintage Ar, or Simply Sound (linked via a reference here to Layne). Are these the same tweeter, just from differenct vendors?

3. Use the HiVi from Parts Express.

Hi Jim,

I think you and Kent and Pat have summed it up pretty well...

Just to clarify and repeat a few things:

-None of the replacement tweeters will match an original tweeter. It is best to replace in pairs, or find a used original to match another original.

-You are correct...AB Tech, Vintage AR, and Simply Speakers are selling the same replacement tweeter sourced from AB Tech, which wholesales it to the others. It can be made to work more or less acceptably with a .05 to .07mh parallel inductor, but it is very pricey relative to the sonic results. It fits the hole very nicely.

-The HiVi tweeter can be made to work fairly well with a .05mh parallel inductor (in ALL models). The HiVi is not a bad fit, but you would have to drill holes in the faceplate to use the AR screws, or use the existing HiVi faceplate holes with deep thread #6 or #8 screws (also available from Parts Express). I am now recommending the smaller .05mh inductor across the board along with reducing the crossover cap to 3uf, if the goal is to get as close as possible to the original tonal balance. The original recommendation was meant to leave the original crossover component values as is in anticipation of acquiring original tweeters in the future. This is becoming much less likely as time goes on, and the smaller coil and cap tweak seems to be preferred by those who have tried it.

-Reversing the polarity of the HiVI and AB Tech tweeters relative to the original tweeter was part of my initial recommendation, and technically correct when adding a parallel coil, but the differences are quite subtle. The degree that the added parallel inductor shifts the phase response of the tweeter has not been determined. It is something worth experimenting with if you are a tweaker.

-There are many folks happy with l-pads as is. OTOH, an added parallel 25 ohm resistors across the tweeter and mid will allow l-pads to attenuate them more like original AR pots (for the first half of the rotation). It also maintains the original crossover points accordingly.

-When using the replacement tweeters, straight l-pads may be preferable to some people who want a bit more output compared to the original tweeters. The replacement tweeters are different enough from the original tweeters to make the pot vs l-pad issue less critical to the tweeter circuit. This could be considered a matter of preference.

-Bear in mind NONE of the AR parts sellers are selling new AR pots. They are simply hawking ordinary $4-$5 l-pads marked up to stupid prices. The same l-pads can easily be purchased from sellers like Madisound, Parts Express, and Erse for much less.

-Madisound also sells the HiVi Q1R tweeter, as well as a nice selection of caps.

The main advantages to the replacement tweeters discussed above are ease of installation, and reasonably acceptable sound relative to the original. There are other forum members who have adapted modern tweeters to their satisfaction, but faceplate adapters or modifications are always part of the mix. Crossover modifications are ALWAYS required with any modern replacement tweeter *IF* the goal is to keep the speaker as close to original as possible.

If you still need some help deciding on a course of action send me a PM. I would be glad to be of assistance.

Roy

[JKent]

sorry--goofed

[jims]

I see I have attained the rank of newbie. I cannot thank those of you who replied enough. This will narrow my choices and help get this project moving forward as I have been without sound for some time now. I will show this to my tech and see if there are any additional questions in case I need to take Roy up on his generous offer. He has worked on AR's in the past so this will likely be clear to him.

I will report back on our results.

Also, JKent I must have been AR'd out at midnight when I tried to morph my turntable brand. You were very diplomatic in pointing this out!

[oldarnut]

The two tweeters from PE or Madisound are 6 ohms--halfway between the 4 and 8 ohm tweeters for 3a's/LST's and the 2ax/LST2's. Would you use these in LST2's or is there a suitable 8 ohm model? I need replacements for my four 3a's and one LST2. I've purchased used original AR tweeters and tried Vifa and others with poor results. I realize the AR models mentioned sounded "dead" when new, but when the tweeter output is so low you can't hear them at all unless your ear is directly over them, there is something wrong. My AR3's and Infinity Quantum tweeters output a lot higher level than any of the 3a or LST1 original tweeters I have.

[JKent]

Hey Nut

There is a thread going on now that addresses the LST-2 replacement issue and it seems that if there are no originals available, the Hi-Vi Q1R with a .05mH coil is a good replacement, just as it is for the 3a and the 2ax. I have them in my 3a's and they sound good. Roy advised me that one should make a crossover mod though: Either replace the 6uF tweeter cap with a 3uF, or put an additional 6uF in series with it. That can be done easily when you install the Hi-V- tweeter by splicing a 6uF cap into the black wire that comes from the Hi pot to the - terminal on the tweet. This only works on the 3a. I don't know how to do it on the LST-2.

when the tweeter output is so low you can't hear them at all unless your ear is directly over them, there is something wrong

Not necessarily. Try the toilet paper tube trick. Put a toilet paper or paper towel tube over the tweeter and listen through it. That blocks out a lot of the mid and woofer and lets you hear the highs coming from the tweeter. The 3a is really a "super-tweeter". The xo point is quite high (5000Hz) and there isn't "that" much music at that level. OTOH, the xo on the 3 is even higher (7500) so if they output "a lot higher" maybe there is something wrong with your 3a's.

Kent

oooops. I typed the above after midnight. Just corrected it. For the 3a, adding a 6uF cap in series will lower the capacitance to the desired 3uF.

[RoyC]

I realize the AR models mentioned sounded "dead" when new, but when the tweeter output is so low you can't hear them at all unless your ear is directly over them, there is something wrong.

oldarnut,

There really is nothing "wrong" in accordance with the original design, and re-designing the speakers to make them "right" to your ears is another topic altogether. Properly implemented replacement tweeters for these AR models will not sound much different than the original tweeters. The speakers you cite in comparison were *designed* to have tweeters reproduce frequencies lower than 5000hz, which is MUCH more audible when listening to just the tweeter.

Read the first part of this thread pertaining to this issue:

http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=6659

Another complicating factor when evaluating these tweeters by ear is the fact that older ears often do not hear well at the high frequencies they were designed to reproduce.

Roy