Joel Posted November 27, 2011 Report Share Posted November 27, 2011 I was in a thrift store today with my wife, and found a pair of AR4x's for $59.00. I briefly hooked them up, and they don't sound too good. I'm sure there isn't any sound coming from the tweeters. I found this thread on AK: http://www.audiokarma.org/forums/showthread.php?t=306818About the speakers. They have serial numbers fx346696 and fx346322. The surrounds are made of cloth. When I push them in, they pop back out. The thread above mentions using gasket goop to seal them.The cabinets are in ok shape, I'll probably leave them alone for now.I am going to give a shot at restoring them. Any advice would be welcome.-Joel Link to comment Share on other sites More sharing options...
JKent Posted November 27, 2011 Report Share Posted November 27, 2011 Hey JoelThat AK thread is very good. A few comments: My 1st speakers were AR4x, purchased in 1969. I still have them and use them daily.The cloth surrounds may indeed be porous. You could use the gasket cement, very sparingly, thinned with toluol. There is a lot of discussion about that here. A better product, if still available, is some stuff RoyC whipped up in his lab. Try sending a PM.The tweeter problem is probably just the pots. That AK thread addresses cleaning the pots, or you can just replace them with inexpensive L-pads (about $5 from Parts Express).One important thing was left out of the AK thread: Replace the capacitors. You can leave the old wax cap in place and just cut the wires, then install a new 20uF film cap. Dayton, Solen, Erse and Carli are all good choices. Erse Pex is the cheapest at $4.14 ea. Daytons, Erse PulseX and Carlis are about $6. Solens about $7.65, or try Clarity PX for 15.50 ea. Wouldn't go any more exotic than that. My choice would be any of the Erse caps.For your cabs, the Howard RAF works surprisingly well. Use fine steel wool. Afterward you can apply Watco Danish Oil and/or the Howard Feed n Wax.Good luck.Kent Link to comment Share on other sites More sharing options...
kirk57 Posted November 28, 2011 Report Share Posted November 28, 2011 I've just done all this (new caps,new wires, clean pots, new grille cloth, refinish cabinets, redope surrounds with RoyC's goop) to my AR-4x's.I found that bypassing the pots entirely helped a lot. Link to comment Share on other sites More sharing options...
Joel Posted November 28, 2011 Author Report Share Posted November 28, 2011 I spent the day working on the AR-4X's. It was an interesting project, and I think it went well. The pot was a lot better in one of the speakers, but after cleaning they both work. The better pot is smooth all the way through its range, but the other is spotty. I'm thinking I should replace that one with a L-Pad- should I just replace them both? What are the specs I should look for in ordering them?I want to recap them, and it looks like an easy project.I doped the surrounds- this made a big difference.Are these 4 ohm or 8 ohm speakers? The label on the back says to connect a 0 ohm and 8 ohm amplifier to terminals 1 and 2.Thanks.-Joel Link to comment Share on other sites More sharing options...
JKent Posted November 28, 2011 Report Share Posted November 28, 2011 Hey Joel. You're on your way! This could become an obsession (just a warning).Here are the L-pads. If you go that route replace both. L-pads and pots are not exactly the same. Besides, even cleaned pots will eventually corrode again.http://www.parts-exp...tnumber=260-248If you get the pots from PE, may as well use these caps:http://www.parts-exp...tNumber=027-436or these, but they are not worth the extra $$ IMHOhttp://www.parts-exp...tnumber=027-582Your speakers are 8 ohm.Good luck. Ask questions here if you get stuck.Oh--here's something you need to know: The terminals on the pot are marked B, 1,2. The L-pad terminals are 1,2,3. When you replace the pots, B = L-pad terminal 2. 1 = L-pad terminal 3. 2 = L-pad terminal 1.Below is a photo from RoyC showing the pot & L-pad. Don't bother with the resistor on the L-pad--that's for use with mids in 3-way systems. The only caveat is you probably should not crank the the L-pad up to absolute maximum. If you like a relatively high tweeter output turn the L-pad control all the way clockwise, then back off a bit.Kent Link to comment Share on other sites More sharing options...
Joel Posted November 28, 2011 Author Report Share Posted November 28, 2011 Kent,Thanks. I was wondering about the watts rating on the L-pad, but the 15W is ok? I had read about the resistor, so its good to know I don't need it.Could there be any damage if the L-pad is turned to max?-Joel Link to comment Share on other sites More sharing options...
JKent Posted November 29, 2011 Report Share Posted November 29, 2011 Old tweeters, without ferrofluid, do not like to be stressed. So you should be cautious about cranking up the tweeters regardless. Having said that, here is a note I received from Roy:The only real concern when using l-pads is that the "maximum" setting removes the series and parallel resistance, consequently directing more power to the drivers, so care must be taken if the user's preferred setting happens to be maximum/fully increased. I have not found this to be a problem in actual use. I have spoken to Larry Lagace (Ebay's "Vintage AR") about this at length. He and AB Tech have sold literally hundreds of l-pads to AR users, and have had no reports of problems resulting from their use.Of course YMMV Kent Link to comment Share on other sites More sharing options...
JKent Posted November 29, 2011 Report Share Posted November 29, 2011 OOPS. I misrepresented what Roy told me. The resistor IS appropriate for the 4x. I was basing my comment on the fact that Roy uses the resistor on the mid, but not the tweet, in the 3a. However, the 4x is a different animal. OTOH, when I put L-pads and new caps in my 4x's about 5 years ago, I did not use resistors. I don't think it's a big deal. If you already ordered your caps just go ahead with the cap replacement and if you find the tweeter is sounding harsh, add the resistor later. If you have not placed the order yet, you could order a couple of 10w 25 ohm resistors like these:http://www.parts-express.com/pe/pshowdetl.cfm?Partnumber=004-25Sorry if I led you wrong.What did you use to dope the surrounds?Kent Link to comment Share on other sites More sharing options...
Joel Posted November 29, 2011 Author Report Share Posted November 29, 2011 Kent,I ordered the L-pads, and threw in the resistors just in case- so I'm good. Where exactly do the resistors go? I used the permatex stuff for the surrounds.They sound ok, but my main speakers are AR90's, and nothing else I listen too comes close to those. It makes it very hard to judge the quality of other speakers. I'm not sure what I am going to do with the AR4x's. My wife would like them for her sewing room, but they are a little too big. How big of an amp do I need for them?-Joel Link to comment Share on other sites More sharing options...
JKent Posted November 29, 2011 Report Share Posted November 29, 2011 Hi JoelI think the easiest is to put a resistor across the L-pad terminals in shown in the photo above. Right. The 4x will never compete with the 90s. They'd make nice rear surround speakers though. Or put them in the sewing room.My 1st stereo consisted of AR4x speakers driven by a dynaco ST-35. That's 17wpc. Worked fine for me.Kent Link to comment Share on other sites More sharing options...
dualref Posted December 2, 2011 Report Share Posted December 2, 2011 My very first stereo system was a Pioneer SX-434 and a set of AR-4x speakers back in 1972. Even though the SX-434 was pretty low powered the AR's sounded great. Better than most other speakers of that era. When you are done with them, you will really enjoy them. Link to comment Share on other sites More sharing options...
Joel Posted December 3, 2011 Author Report Share Posted December 3, 2011 I change the pots to L-pads, and changed the caps today. They really do sound good for such a small speaker. Now I have to figure out what I am going to do with them.Thanks for all the help.-Joel Link to comment Share on other sites More sharing options...
Whitecaps18 Posted December 8, 2011 Report Share Posted December 8, 2011 L-pads ensures correct crossover frequency independent of setting where "pots" are a variable resistor. The AR4x is a favorite of mine, I use a product called "White Loudspeaker Surround Dampener" to re-seal the fabric surround from ProSound in Braintree, Mass. What is great about this product it dries clear but does not stiffen or change the characteristics of the fabric surround which is critical. Use of other sealants will potentialy have detrimental effects on the woofers resonant frequency Link to comment Share on other sites More sharing options...
JKent Posted December 8, 2011 Report Share Posted December 8, 2011 The issue of sealing fabric surrounds has been discussed extensively here. The white dampener is sold by M_Sound and others for use as adhesive for new foam surrounds, a treatment for paper cones, and as mentioned a sealant for cloth surrounds. Some members here and on AK have experimented with Permatex for sealing cloth surrounds. Some of us here have used RoyC's home-brew formula on cloth surrounds with excellent results. It is more like the original toluene/butyl rubber product used by AR and KLH, and recommended in the KLH Service Bulletin in the Library section here.My advice: Any product used to seal cloth surrounds must have the ability to remain flexible forever and must be applied very sparingly. I highly recommend Roy's goo.Kent Link to comment Share on other sites More sharing options...
dualref Posted December 13, 2011 Report Share Posted December 13, 2011 Where do we find the recipe for Roy's goo? Link to comment Share on other sites More sharing options...
JKent Posted December 13, 2011 Report Share Posted December 13, 2011 Where do we find the recipe for Roy's goo?Send him a PM. You can only get the finished product--not the formula AFAIKKent Link to comment Share on other sites More sharing options...
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