Jump to content
The Classic Speaker Pages Discussion Forums

RoyC

Members
  • Content Count

    2,303
  • Joined

  • Last visited

Community Reputation

0 Neutral

2 Followers

About RoyC

  • Rank
    Advanced Member

Contact Methods

  • Website URL
    http://
  • ICQ
    0

Profile Information

  • Gender
    Male
  • Location
    Latham, NY

Recent Profile Visitors

14,538 profile views
  1. RoyC

    Original AR 3a's???

    I agree, Tom...I overlooked the mdf edges of the sides, top, and bottom panels, which can be seen in the photos. (I'm still convinced the grilles are reproductions with original badges.) I also agree regarding the woofers. The surround looks very much like the replacement sold by "Simply Speakers" for quite some time, which had a wider outside lip. If so, it is also possible the woofers were treated with a Simply Speakers product called "Foam Guard". Roy
  2. RoyC

    Original AR 3a's???

    Hi guys, -The walnut clad plywood cabinets are not unusual for the serial numbers, though cabinets constructed from a combination of mdf and plywood were not far off. The cabinets appear to be in very nice condition. Kent, though the inner edges varied a bit, it is where the hot glue was applied to secure the original 3a grilles. With the exception of very late AR-3's, the earlier AR-3 type cabinet did not have this grille mounting arrangement, and may be what you are thinking of. Most AR-3a cabinets are like those in Steve's photos. -The grille frames and material have been replaced. The front surfaces of the original frames were painted black. These have wider edges and are not painted. -As mentioned above, the tweeters are not original. They appear to be old Peerless tweeters. They may work satisfactorily with a parallel coil (as with the HiVi tweeter), but experimentation would be required to determine suitability. -The trim rings on the tweeters and mids are not original. I'm guessing the tweeter ring was added to hold a smaller tweeter faceplate in place. From what can be seen, the mids appear typical of the cabinet serial numbers, with the surface leads running under the added trim rings. -As Kent pointed out, the black AR badge is not original to the 3a. Roy
  3. RoyC

    A pair of AR-3 fell into my lap this week

    Those serial numbers actually indicate earlier production specimens. Over 70, 000 were manufactured. Your JBL's are from a later era. AR-3's were not sold as pairs, and it is very unusual to find a pair with consecutive numbers. Mono amps were common in the early 60's, and "stereo" was in its infancy. A difference of 37 is really quite close for a pair of 3's, and indicate they were most likely purchased together. Roy
  4. RoyC

    Who for Vintage speaker repair ?

    "Roy" here...Welcome to CSP. Shipping your speakers can be a daunting task. If you are inclined to do the work yourself you will find a wealth of information and experience in this forum to guide you. If you prefer otherwise, and are able to ship them to NY, I'm sure I can be of assistance. Personal message sent. Roy
  5. RoyC

    AR3 Mid Range Differences?

    Are you sure your 3's were not repaired along the way? Your crossovers may provide a clue. http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_schematicss/thoughts_on_ar-3_schematics/ Roy
  6. RoyC

    AR3 Mid Range Differences?

    Welcome to CSP, Snow... The fiberglass pad showed up very early in the game, but the large magnet version of the AR-3 mid was used until the rounded magnet version was introduced around serial number 30,000. Only the earliest ones had no fiberglass pad. Most were equipped with the pad. Roy
  7. I do most of his repairs. Forum members can contact me directly through the forum. The 3a mid and tweeter have copper tinsel leads. When necessary, I usually extend them with 24ga or 26ga stranded, tinned wire, using ordinary electrical solder. AR-3 mids and tweeters have aluminum leads requiring special solder, and are more difficult to deal with. Roy
  8. RoyC

    Ar3 midrange

    I wouldn't hesitate to use the AR-11 mids, Ken. Roy
  9. RoyC

    Ar3 midrange

    That is easily your best bet. It is likely those overpriced AR-3 mids have the old caked material around the domes requiring work to remove it. There is no need to convert your 3's to 3a's. Simply use the last AR-3 crossover with the later mids. Roy
  10. RoyC

    Ar3 midrange

    arken, The AR-3 tweeter held up better than the first two versions of the AR-3 mid. It is also much more available, having been used in the popular AR-2ax (first version), so your tweeters shouldn't be a problem. On the other hand, finding decent non-3a type AR-3 mids anytime soon will be very difficult. You are likely in for a very long, and ultimately costly, wait. If I were you I would go with a pair of AR-3a or later mids and use AR's .4mh coil/30uf cap modified crossover as mentioned above. I have not done any careful listening comparisons with the earlier versions of the AR-3, but I have made this repair a number of times for other people and it sounds quite good...certainly much better than any AR-3 with a typically degraded/non-restored earlier mid. Bear in mind, use of the later AR dome mid simply converts your speakers to a later version of the 3. They would still be considered "AR-3". If by some miracle, you were to find a couple of worthy earlier mids down the line, it would not be difficult to convert your speakers back to original. I have a hunch, however, you would not find it necessary to do so. The LST is not without issues (four typically degraded tweeters in each cabinet). They often start at $2500+/- a pair, and shipping them is an absolute nightmare. The last two restored pairs sold by "Vintage AR" went for $4000/pr. It is probably best to stick with your AR-3 project for now. Roy
  11. RoyC

    Acoustic Research AR-5 rebuild service

    Pete, Earlier front-wired 3a mids measure below 3 ohms. Later back-wired mids through the AR-9 typically measure 3.2 to 3.5 ohms. (Your AR-11 mid seems to be a bit on the high side.). Two later back-wired AR-5 mids I recently measured were both 5.2 ohms. All the AR-5 mids I've measured in the past have been around 5 ohms, with earlier front-wired specimens, like the 3a mids, being on the lower end of the range. I estimated the series resistance on the high side primarily because the white dot/"normal" setting of the AR-5 mid pot is nearly 50% off maximum (around 6.5 ohms in series), so there is plenty of output to be had with the AR-5 mid. The prudent way to go would be to measure dcr and add enough series resistance to the intended low impedance mid to achieve 5 ohms. This would put it well within the desired spec. It should also be noted that the original "15 ohm" pots can vary by as much as .5 to 1 ohm one way or the other, and should be measured as well. Roy
  12. RoyC

    Acoustic Research AR-5 rebuild service

    Yes...and all of the LST-2 drivers are the same as the AR-5 drivers. Roy
  13. RoyC

    Acoustic Research AR-5 rebuild service

    Sure, a 2.5 ohm resistor in series with an AR-3a mid will bring it very close to an AR-5 mid. Roy
  14. RoyC

    Acoustic Research AR-5 rebuild service

    Yes, they are constructed very differently. The AR-3 mid is essentially a large version of the orange phenolic dome AR-3 tweeter (foam suspension blobs, aluminum voice coil wire, etc). The 3a and 5 mids have more modern construction with a cloth dome/rolled cloth suspension, among other differences. Roy
  15. RoyC

    Acoustic Research AR-5 rebuild service

    Hi guys, I've been repairing the AR-3 mid, not the AR-3a/5 style mid. Roy
×