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Aadams

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Posts posted by Aadams

  1. 39 minutes ago, ReliaBill Engineer said:

    ’ve been listening to these a lot over the last several days. I’m not wanting for treble at all. These don’t need an “augmenting” super tweeter. I’ve read that many times from owners of both the 3/3a and 2ax owners. Long discussions about which tweeter and which crossover point to use. It isn’t needed on these. These have ample treble output that is clear as a bell.

    Good job getting them to match. 

  2. 51 minutes ago, Jab said:

    So, the implication would be if they were replaced, it was with AR replacements...

    I do not have 8 inch ARs from that period but all the replacements I have seen say " Service Replacement" on a very similar the sticker.  I thought yours might be service replacements when I first saw your photo. Yours are probably original, but bearing a service mark from the company that refoamed them.  Assuming all your voice coils are good, you will spend several hundred Euros to have better speakers than if you merely refoamed those originals.   Otherwise they are marketable as is in Italy, which had a large AR following.

  3. 17 hours ago, giovanni56 said:

    That it is triamping would be confirmed by the six rear connection terminals but I don't understand why only four are used.

    It looks like they might have been bridged for Bi amping.  That is a guess.  The good news is they are not Cello nor are they AR original and therefore have no provenance of value.  They  are worth the price of their working parts but could become a very good deal if they can be easily restored to proper working state with existing circuitry .  I would bridge all three terminals for use with an equalizer and a single MODERN power amp.

    Edit: I reread the first post and see they are not currently for sale. 

  4. 17 hours ago, giovanni56 said:

    I can't send decent photos because the site only accepts photos of ridiculous size 10kb, why is this happening,??? back in the day this problem didn't exist, you could send heavier photos, now you can't sin.

    If you are trying to post directly from a phone you could have a problem. It always works when you resize on a computer.  At least for me.

  5. 11 hours ago, genek said:

    Do we know which of these curves Harman was producing speakers to conform to in the 80s and 90s?

    No. The information in the chart was first presented in 2015, as far as I know.

    To my eye, it appears that the AR curves are closest to Toole's "Trained Listeners Only."

    Yes. You are correct

    All of the listener curves are considered valid and acceptable.

    The chart is saying the only way to satisfy the preferences of most home listeners is to design high quality loudspeakers that can produce steady state "sound power" throughout a home listening space as represented by the heavy dashed line.  I added the red lines to highlight range of effect due to reflectivity in normal listening spaces.

    image.png.e5e6173512775dbb312dff84ce8883a3.png

    The heavy dashed line is not an on axis line. It is the Harman version of this

    image.png.80ba6158f8a07a92e5c2ab34faa70127.png

    The paper is freely available at the link above.  In addition to target curves for loudspeaker design, there are Harman target curves for Cinema and Studio spaces. All of which are aimed at satisfying the tastes of listeners in those spaces;

    Akin to Roy Allison creating speakers to meet the expectations of a listener whose ear is attuned to the acoustics of Boston Symphony Hall.

     

  6. 3 hours ago, genek said:

    wonder how the "Harman Curve" compares to the old Harman standard, which, IIRC, was whatever the majority of listeners in Floyd Toole's 1980s blind listening tests said they liked best.

    Turns out there is a graph that answers your question from Lansing Heritage

    image.png.b82d101128541ac75821cb7ae7a43ebd.png

    The bold dashed line is close to the published target of Revel and some JBL

    Compare to these below

    image.thumb.png.21ff0e3f93f751c720a093b140f0025e.png

  7. On 4/14/2018 at 6:21 PM, genek said:

    Everything I've seen in this discussion leads me to conclude that it would cost a lot more to buy new speakers and try to get classic AR sound out of them than it would to buy classic ARs and restore them, even if you had to pay someone to do the work for you. 

    Update:

    The above is still true but Harman International now, in 2023, explicitly states that speaker brands Revel, JBL Synthesis and JBL Professional  are intentionally designed and built to achieve in room performance that conforms to the "Harman Curve" for loudspeakers, which looks and reads an awful lot like the AR philosophy for loudspeakers from Roy Allison days.

    Entry pricing for 2 way six inch is about $600 each.  JBL L100 Synthesis, @ $5k/pair,  which looks like an L100 Century is in this group. 

  8. 54 minutes ago, ThomasL said:

    But if we assume that there is an adapter would it influence the sound? Do the two different woofers sound alike? 

    It is possible that both speakers contain their original drivers. The factory would have installed an adapter for the 4 hole woofer.    Inside the box, AR would have accounted for the different woofers by changing the crossovers and the speakers would sound perceptibly identical when new.    The problem for me is the 6 hole woofer is wrong. It could be the original frame with a new cone and voice coil or it could be the wrong part altogether.  So.......................Assuming the speakers have not been modified internally and the only alterations are what we can see in photos:

    If you are critical listener they will not sound identical in their current form.   If you are a casual listener they may sound good enough.

    You haven't mentioned the price.  To me, in their current state, they are worth the combined value of their seperate, working, genuine AR parts on ebay.  Maximum.

     

     

  9. 4 hours ago, ThomasL said:

    Any of you have an opinion on this? 

    It looks to me like both cabinets were cut for the earlier and larger diameter 6 hole frame woofer.  One woofer is a 6 hole and the other woofer with the flat dust cover is the later 2ax woofer with 4 holes.  Both woofers may be AR but I can't recall ever seeing an early 6 hole 10 inch woofer with a smooth paper cone. 

    The 4 hole frame is too small for the woofer opening and would need an adapter to correctly seal the cabinet.  I can't see an adapter ring in these photos

    The only way to really know is to extract the 6 hole woofer and look at the magnet for date and model info.  I would consider this pair as compromised and be looking for matching woofers which could be difficult in Denmark.  They are not worthless but they are not at an ideal starting place for restoration if you want a matching stereo pair.

    Others may have more to say.

    Good luck.

    Otherwise the speakers look good in the photos.

     

     

  10. 1 hour ago, RoyC said:

    The notches were model specific and were there to place the arrow of the pot shaft in a specific position relative to the white dot.

    So the board ,3a 2ax etc, received specific notches for the pots somewhere after it was cut and printed  but before it was populated and wired.  Is that correct?

  11. Did you skip the step where you compare the 2nd, untouched, tweeter to the restored tweeter?  I can't find your analysis of that comparison. 

    Apparently pots had enough unit to unit variation in performance that they had to be measured and preset before being installed in a specific position to make it simple for the user to set up a stereo pair. Most of us found out about the notches after the fact.  If you are going to keep appearance and parts as original, installing the pots as original is very simple compared to your tweeter work, which practically none of us can do.

    I still think original is always preferred but in the case of pots, unless they were spotless, would replace the original pots with LPads and resistors or modern pots.  The pot tab notches become superflous.  If you keep the speakers you will revisit those pots.

    The AR2ax incorporates the super tweeter in a way that makes the unmeasured performance of your repair easier to accommodate if it is extending too far into the midrange.  The tweeter was originally designed for the AR3 which had very specific performance requirements to blend with the dome mid at 7500hz.  If its natural rollof is not correct it would be noticeable in an AR3 application.

    All that matters is your tweeters sound like a matched pair.

    All Classic ARs sound very similar,  If you want your speakers to sound like an AR, this is the target for an AR2ax  EDIT  with the controls set to full increase.  They will sound unbearable in a normal room to most listeners.  I think you are within range.

    image.png.2a569510cfe32dd419f8d86beb108d4f.png

     

     

     

     

  12. 3 hours ago, RickB said:

    Any thoughts on this issue?

    I installed 3 sets of Dayton Lpads several years ago.  I noticed the behavior to which you refer and thought it was the "full on" feature.  Rebuilt tweeters don't need that level of signal but it might help those that have not been rebuilt.

  13. 16 hours ago, ReliaBill Engineer said:

    As long as I can get balance by adjusting the pots, I’m satisfied. The fact that I can get balance within the adjustment range of both pots, tells me I’m where I need to be with the tweeter output. And getting balance with both, AND the woofer, is a wonderful sound! Currently I’m at 80% on the tweeter, 60% on the mid-tweet.

    Your result is probably close enough because your pot settings are in the range of the most common settings for AR Classic 3 way or 2.5 systems.  The appearance is also correct.  I can count on two fingers the number of other people who are known to do this specific mechanical repair. 

    The most important goal is for you to create a matched pair.  It would be a bonus to be able to match the performance curve of the original spec for the AR3 which was aimed at linear power response rather than high on axis output.

    According to history on this site, reject rate for the four blob tweeters was high with a large percentage being sent back for rebuild.

     

     

     

  14. I think you have plenty of monitors.  I, for one, am waiting for the second tweeter results.  One question:  Considering this is a stereo pair, if you rebuild the second tweeter in a different fashion how do you insure they will have near identical performance? 

    Also, if you omit the 4 dots on the second tweeter does it count as mod or restoration? Assuming it works correctly.

    The CSP community has never been much of one for watching videos of AR speakers playing on computer speakers.

  15. The domed tweeters were added to prop up the power response of the mid/tweeter 2 series.  The domed tweeters were never intended to be on-axis spl demons. The graphs below may help.  The tweeter is the later 3/4 inch but the effect is very similar with the 1 inch tweeter.  The graph shows he mid tweeter of the 2ax responding above 10k on axis. AR6 on the right hand side.

    image.thumb.png.e53f6e41ac5d816216aac22de21f56ab.png

     

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