I've got 2 pair of 4x's

[HarryM]

I went for a drive saturday to pick up what I was told was a pair of AR 4's and when I got there I found out they were 4x's.Then I went another 186 miles,or 300 km for my fellow canadians,to pick up what I knew were 4x's.I got them home and opened them up to find both pairs are from 1968.The one pair sn 179936 and 179917 tweeters are both stamped Aug 9 1968 and the woofers are stamped 8w 2748 137 6805.The other pair sn 175849 and 173213,I could only make out the date on the tweeter in 173213 as June 19 1968 and no numbers ledgable on the woofers on this pair but they are not the same woofers as the first pair but are quite close just different cones and baskets.LOL.I have not had a listen to them yet because the woofer surrounds need coating and I'm going to recap them.All 4 cross overs are the same with a #4 coil and 20uf caps.

My plan in the near future is to a,b,c,d them with a pair of klh 38's and a pair of adc 303b's.Both the 303b's and the 38's are 10" 2 ways so the 4x's have there work cut out for them.All speakers will be recaped and sealed.I will also a,b,c,d them against my AR 25's and 28s's to see how the old compares to the newer small AR 2 ways.The cab size is pretty close to the same so it should be a fair fight.

[ra.ra]

Sounds like a nice road trip and a great project. I have attached a pic of my two pairs of 4x's (pre-restoration) and you can see that my woofers also have two distinctive cone types - one pair smooth and the other ribbed. Too bad your first pair were not AR-4's as advertised - I've recently come upon a great pair of 4's and it is fun to compare them with the 4x speakers - - - see second pic for comparison of drivers.

I find it difficult to describe qualities of aural sensations, but at the moment, I am tending to feel that the 4's produce a more full spectrum throughout the midrange frequencies, but the 4x's have a bit more pronounced high end.

Caps and surrounds are great places to focus restoration efforts, but as you probably already know, do pay equal attention to diagnosis and restorative maintenance on the tweeter control pots, too, or your efforts may not achieve the full desired results. As a thought, it may be of interest to install two different brand of caps - - - I went this route (Erse and Solen), but have not yet been able to make side-by-side comparison of 4x's (one pair remains incomplete).

[JKent]

Some 4x's used the 4 woofers. Earlier woofers were ribbed and had 4 bolts, later ones were smooth and had 8 bolts. Profiles, depth of basket, magnet all changed over time, too. Attached are some photos of 4x woofers.

btw--Roy turned me on to a cool mod. Replace the drivers and xo with those from an Avid 101. The Avid woofs have rubber surrounds, the xo has a film cap and everything just drops right in with no cabinet mods. The Avids sound great but had crappy woodgrain vinyl cabinets. I have not done a side-by-side listening test.

For more on that "mod" (really a transplant, see post #13 here: http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=6659

Kent

[HarryM]

Thanks for the responses.

ra ra it was a nice road trip,I got to see a friend I've seen maybe 5 times in the last 18 years or so while I was out there.

One pair of woofers looks to be the same as your pair on the right but the other pair don't match your pair on the left.The pots are going to need attention as well.I think one pair will get Lpads but I may beable to save the pots in the other pair.

Since I didn't get ar 4's this time I will still be looking for them.I had wanted to a,b 4 and 4x's just because lots of people here write very highly about both of them and I was feeling left out.LOL.I will say I have always prefered 10" woofers but with all the talk about these I just wanted to hear them for myself.

JKent I do have one pair with 4 bolts and one pair with 8 bolts,I was a little surprised that they had different woofers being less then 3 months apart.

I guess I will have to look for some avid 101's to try this mod.LOL.Then when I find a pair of ar 4's I'll a,b,c all 3.If I really like the mod I'll do both pairs because I would like to have both pairs match for a 4 speaker set up when I just want to listen to music with out shaking the house.I will save the original woofer though.

[ra.ra]

On one pair of my 4x woofs, the basket frames have four holes; on the second pair, the basket frames have eight holes - - - but I've never seen an AR 8" woofer that was actually secured to the baffle board with eight (8) separate machine screws. In my close-up pic of the comparative drivers, you can see the eight hole basket on the 4x speaker (right), but it has only four screw and T-nuts at the 45 degree positions. What you see at the 12-3-6-9 o'clock positions is the rope caulk sealant oozing thru the remaining basket holes. I'm not exactly sure where these particular basket frames were ever used in speakers with eight fasteners, but I do know that other manufacturers' products (EPI-100, e.g.) did use 8" woofers with eight screws or bolts, filling all the frame holes.

As many have stated here, there were many iterations of the 8" woofer used in the AR-4x, but I find the side view pic provided by JKent to be extremely interesting - - - look at the difference in the sizes of the magnets!

[HarryM]

Yes my 8 hole woofers also only have 4 bolts.I also found the side view picture interesting,they look completly different and yet based on what I've read on this site they sound about the same.It most be all about the voice coil.