Okay, these AR12 are awesome!

[DavidDru]

Shockingly good after a recap and new surrounds on mid and woofer.  New trim pads on tweeter and mid that I got from Glenn.  WOW! is all I can say.

I have them in my 12' x 12' room hooked up to my WOPL 400 (230/ch) SS amp and tube preamp and they absolutely jump out at you and image great.  Really good detail and the bass is all you need in this room at all levels.  Also tried them with the Dyncao ST70 and now with a The Fisher TA600 tube receiver and those do well with them also.  A bit more gain is required of course.

I used Dayton 1% poly's in the recap.  Will probably go back in and replace those darn AR binding posts.  Damn things drive me crazy!

Next up though is fabricating some new grilles.  Going to go with the raised beveled edge like Glenn did in his.  I may contact foamspeakergrilles to see what they would charge to make some up like I have for some big Altecs.

I am full in on looking for AR11's or 10pi now.

[lARrybody]

2 hours ago, DavidDru said:

Will probably go back in and replace those darn AR binding posts.  Damn things drive me crazy!

Hey David,   just make something like this and leave the binding post original.

Which version do you have? Mine are the early ones with the brass name plates. I too used Dayton capacitors with film and foil bypass capps.

[GD70]

3 hours ago, DavidDru said:

Shockingly good after a recap and new surrounds on mid and woofer.  New trim pads on tweeter and mid that I got from Glenn.  WOW! is all I can say.

I have them in my 12' x 12' room hooked up to my WOPL 400 (230/ch) SS amp and tube preamp and they absolutely jump out at you and image great.  Really good detail and the bass is all you need in this room at all levels.  Also tried them with the Dyncao ST70 and now with a The Fisher TA600 tube receiver and those do well with them also.  A bit more gain is required of course.

I used Dayton 1% poly's in the recap.  Will probably go back in and replace those darn AR binding posts.  Damn things drive me crazy!

Next up though is fabricating some new grilles.  Going to go with the raised beveled edge like Glenn did in his.  I may contact foamspeakergrilles to see what they would charge to make some up like I have for some big Altecs.

I am full in on looking for AR11's or 10pi now.

They will get better as the surrounds loosen up a bit. Good to hear you're liking them so much! I've thought the same thing regarding persuing the 11's and 10pi's, but I'm being really good and not getting any more speakers for now.

Great to see another one year wonder singing again!

Glenn

[DavidDru]

12 hours ago, lARrybody said:

Hey David,   just make something like this and leave the binding post original.

Which version do you have? Mine are the early ones with the brass name plates. I too used Dayton capacitors with film and foil bypass capps.

 

Great idea Larry.  In fact I did do just that last week on a connection to a pair of super tweeters I added to my Concert Grands.

Early ones for me too I think.  They are some sort of metal.  I didn't do the bypass caps.  Suppose I could have since I have those little caps here for that.

 

 

[DavidDru]

I think the surrounds are already there Glenn!  Thanks for the trim pieces for the tweeter and mid.  They look great.  Whatever the adhesive was on the originals is some tough gooey stuff.

Now to do the grille frames.

[lARrybody]

The jury is still out on the bypass caps. Some members swear by them, while others say that bypassing Metalized Polypropylene Caps has little or no effect.  Some say they take the harshness out of Electrolytic Caps. I just don't know. My 12's sounded good with the original electrolytes, which were not that far out of spec. I A-B them before the second speaker was recapped and the new caps did have more  midrange and treble presence and detail. Maybe a bit more crisp, but the originals sounded pretty darn good to me.

Some pictures of your 12's wood be cool. Enjoy them as everybody that has them only has good things to say. Currently working on a pair of nice original 48S speakers and I can't wait to compare them. 

[lakecat]

Another convert...;) I remember several years ago getting a pair and redoing them. When I played them....I about fell down with surprise. I was so impressed that I felt they were better then a pair of AR5's I had here....which probably had people wandering what medication I was on. But....they are slowly coming around as people get them. They are that good and the midrange is awesome.

 

[Aadams]

1 hour ago, lakecat said:

I was so impressed that I felt they were better then a pair of AR5's I had here

This makes sense. A properly working  AR12 with its 400hz crossover should sound very similar to an AR5 and better if the AR5  had a degraded tweeter.   Actually, except for bass extension,  it may have been the best sounding of the ADD series.  AR never had a lower crossover in any three way until the Connoisseur series.

[DavidR]

23 hours ago, lARrybody said:

The jury is still out on the bypass caps. Some members swear by them, while others say that bypassing Metalized Polypropylene Caps has little or no effect.  Some say they take the harshness out of Electrolytic Caps

I now believe in bypass caps after recapping my AR91s with Dayton; the 1% PMPC on the smaller values and the 5% MKP on the larger caps. I was unable to listen for very long before them getting 'under my skin' because of listener fatigue. I now use bypass caps on both electrolytics and film caps but usually only on the series caps.

The idea was promoted by George E. Short III, President of North Creek Music Systems. He worked for AR for a while. He designed and built speakers, made crossover improvements for many well known speakers and made very good film caps: Zen and Crescendo cap . I had read his white paper on the theory that he had posted on his website - wish I had downloaded it before he took it down upon his retirement. I wrote to him and requested he post it again but he never did.

The idea (in short) was to use a small cap, the bypass cap, in parallel to the base cap. The bypass should be up to 10% of the base cap value. The bypass should be a better quality and higher voltage rating. Like a metallized film cap on an electrolytic base cap and a film & foil with a metallized film base cap. He also had another system called Cascading (the Cresendo caps were used) where several bypass caps were used; each addition being smaller in capacitance value BUT higher in voltage rating. JBL used bypass caps in many of their high end speakers. They used very small value polySTYRENE with a polyPRO base cap.

The idea was that the bypass would add it's own characteristics to the base cap AND it would aid in a faster discharge of the base cap. I found that a good bypass would clean up the white noise (grain and glare) in the music. I concluded this with AB tests. I like the Vishay 1837 PP 0.01uF on electrolytics and AudioCap Theta (tweeter base cap) and Cornell Dublier 940C on larger base film caps. I'll be adding a CD940C 0.1uF to my 2500uF cap bundle in my 10Pi and cascading the tweeter in my 91s by adding an RTE polystyrene 5000pF to the current Clarity CSA + AudioCap Theta combo.

[JKent]

I remember my first crossover rebuild: AR-4x speakers, purchased new in 1970. John O'Hanlon guided me through it and recommended using North Creek Zen caps. I think their other line was Harmony. I was pretty ignorant at the time but remember reading descriptions of bypass caps and cascading and being thoroughly confused.

More recently I read the infamous "Humble Homemade Hifi" capacitor test. I'll admit I bought some Vishay 1837 caps for bypassing. Why not? Couldn't hurt--they're less than a buck apiece. Do I hear a difference? No. But YMMV.

As for using pricier caps like the Cornell Dublier ($3) or AudioCap Theta ($6), I'm very skeptical. But if you think they're worthwhile, have fun experimenting.

[DavidDru]

22 hours ago, lakecat said:

Another convert...;) I remember several years ago getting a pair and redoing them. When I played them....I about fell down with surprise. I was so impressed that I felt they were better then a pair of AR5's I had here....which probably had people wandering what medication I was on. But....they are slowly coming around as people get them. They are that good and the midrange is awesome.

 

Grab em if you come across them for sure!  Replacing the surround on the mid and the trim pads around the tweeters and mids make the restoration a bit more work, but well worth it.  I really like how the cabinets look with the thin edges too.  I will post photos as soon as I have the grilles done.

Time to find the 11 or 10pi, although these are probably all I really need in my room with the quality and power of my amplification.

[Theo Wood]

I just acquired a pair of AR12's and I am very impressed. The midrange need new surrounds but they still sound fantastic. 

[lakecat]

14 hours ago, Theo Wood said:

I just acquired a pair of AR12's and I am very impressed. The midrange need new surrounds but they still sound fantastic. 

Dug up from past....time sure flies! Still have these bad boys....but never recapped. It sounds fantastic so never felt the need.

[DavidDru]

Finally got around to doing the grilles on the 12's.  I've been off messing with other stuff including some ground up builds so since I have access to the CNC machine I went ahead and cut out new grille frames.  Had some 3/4" baltic birch that seemed a good way to go since it was going to be painted anyway.

 

[briodo]

The grills (and cabinets) look fantastic.  I did mine last year but did not retain the beveled edge.  After looking at these. I'm thinking they may get a redo.  

Very nice

[ar_pro]

Beautiful - I think it looks better than the original grille! Really nice job.

 

[ra.ra]

David, those look terrific - - that Baltic birch plywood is truly great material to work with, particularly with access to CNC fabrication.

This post is timely - - - just today, I had my first extended listening session with AR-12's. We had a regional swapfest meeting here in east-central MA today that included plenty of system demos, with attendees from as far away as New Jersey. GD70 brought his fully restored AR-12's accompanied by some serious electronics and I thought they were just superb. This model does not show up often, so I'm pleased to see people speaking up with appreciation for the AR-12.

Great restoration project. 

[lakecat]

Very nice David....and how nice to have access to da machine...:)

[DavidDru]

thanks guys.  glenn did his grilles which inspired me to maintain the bevel on mine.  It was difficult at best until I got access to just use the CNC.  Glenn I believe went with 1" wood pieces but I went with the 3/4" BB ply to give it a bit more strength with consideration to those narrow pieces over MDF.  With the velcro they end up nearly 1" out of course.

 

Since these were CNC cut, I suppose I could easily cue up more if anyone is in need of frames.  I can ship pretty inexpensively too.  Let me know.

 

Again, I miss 10" and 12" woofers.

[GD70]

On March 23, 2019 at 8:24 PM, ra.ra said:

David, those look terrific - - that Baltic birch plywood is truly great material to work with, particularly with access to CNC fabrication.

This post is timely - - - just today, I had my first extended listening session with AR-12's. We had a regional swapfest meeting here in east-central MA today that included plenty of system demos, with attendees from as far away as New Jersey. GD70 brought his fully restored AR-12's accompanied by some serious electronics and I thought they were just superb. This model does not show up often, so I'm pleased to see people speaking up with appreciation for the AR-12.

Great restoration project. 

Hi Robert,

I brought the 12's as a last minute decision, one because they are seldom heard, and two, easier to transport than the Angelica's, which I was originally going to bring. I also had a feeling you would be attending and wanted you to hear them. It was good to see you again.

Glenn

[GD70]

On March 24, 2019 at 12:01 PM, DavidDru said:

thanks guys.  glenn did his grilles which inspired me to maintain the bevel on mine.  It was difficult at best until I got access to just use the CNC.  Glenn I believe went with 1" wood pieces but I went with the 3/4" BB ply to give it a bit more strength with consideration to those narrow pieces over MDF.  With the velcro they end up nearly 1" out of course.

 

Since these were CNC cut, I suppose I could easily cue up more if anyone is in need of frames.  I can ship pretty inexpensively too.  Let me know.

 

Again, I miss 10" and 12" woofers.

Hey David!

Those came out great! 

The bypass cap discussion is interesting and something I had not seen before.I have no plans to go back into mine, but may fool around with the idea down the road.

Glenn

[Drew]

On 9/17/2018 at 9:35 PM, GD70 said:

They will get better as the surrounds loosen up a bit. Good to hear you're liking them so much! I've thought the same thing regarding persuing the 11's and 10pi's, but I'm being really good and not getting any more speakers for now.

Great to see another one year wonder singing again!

Glenn

I am new to this forum and have some AR12’s I purchased in the mid 70’s.  Please some advice on tuning them up and restoring them.

[DavidDru]

On 1/7/2020 at 5:17 AM, Drew said:

I am new to this forum and have some AR12’s I purchased in the mid 70’s.  Please some advice on tuning them up and restoring them.

Find Glenns thread on his and see above for now.  Otherwise typical AR restoration principles apply.

[Drew]

David, Will do. Thanks. Let’s say I’m not getting an Ohm reading on a midrange.  I’m guessing it’s the ferro fluid or the voice coil or both. How should I proceed ? Are voice coils and ferro fluid available ?
Drew

[RoyC]

On 1/13/2020 at 3:33 PM, Drew said:

David, Will do. Thanks. Let’s say I’m not getting an Ohm reading on a midrange.  I’m guessing it’s the ferro fluid or the voice coil or both. How should I proceed ? Are voice coils and ferro fluid available ?
Drew

I'm not aware of any rebuild parts for this mid.

Roy