Andre_Db66

Wow! They did put effort and R&D in these because they sound good. How on earth did they get so despised when still a nice product to the ears. Yes, true they are undoubtedly not studio material, but neither is Tannoy for that matter... and other speakers produced by AR are hyped and yet i would compare that also to commercial lines of Tannoy like P series for example. It doesnt make these bad speakers either necessarily. Just because they are not dual concentric. Not trying to compare apples and pears here, but embarresment i think is an overkill statement when they produce excellent companions with lets say a Quad 2 set of 15 watt mono amps. Or even something with only 4.5watts output i built myself using the 832a tube. Andre

Is there anyone on this forum who can provide some serious background on this model or perhaps this line of speakers? Yes they are quite the contrary to AR philosophy with a 15 inch bass reflex loaded design. They are however remarkable speakers that can easily be matched with a low power tube amp and sound amazing. The bass is very deep and the mid/highs are restrained according to earlier models. Only info/rumours i can find is that they were produced for the US army which i find far fetched....? Compared to any vintage speaker standard they are butt ugly and my wife compares them to a paper shredder machine. She is very tolerant, none of that WAF crap or divorce attitude and i must add that with all my speaker adventures the only models she claims are beautiful are my recent LST and also Beovox K series from the late 60s. The rest of my grand collection and past ventures she doesnt care for... Any experiences anyone? Any data anyone? Any comments anyone? Cheers Andre

What i know from experience with rcf and jbl is you at least use a tone generator to verify the position of the coil. Shims i have no experience with and would not know the approach. Leaving out the resonance dampening obviously changes the charachteristics. Is a touch up with regard to dried out glue and resonance cushion even possible or best to to leave it as if it aint broke dont fix it philosophy? Perhaps gently remove the 3 points one by one, whilst adding a ring of new glue, leaving the dampening intact, also the postion of the coil and dome...

I measured the wire used in AR coils and it is 1.25mm thick. I have 1.15mm insulated wire from which i manufactured the coils for the late 3a tweeters @ .16mH using a Peaktech LCR tool. It shows it is around .18R. The small coil with much thinner wire and slightly smaller air core is a coil i unwound until .16mH measuring .5R. This is how i came to my Q about how much the wire gauge is specifically dictating the typical AR sound, or whether it doesnt matter in this case? The first coil with 1.15mm has been applied and thestacked set sound beyond belief. I have/had quite some different speakers but this is amazing! Dre

R.I.P. ra.ra...

The newest tweeters are made of fabric textile and the Frankenstein are the earlier paper cone tweeters with inside connectors. They are all finished as of this morning and stacked upon original stands. I am about to pick up a set of alnico ar6(i hope) and my focus shall shift to the LST2. I have all the parts needed now. This afternoon i will hook up the ar3a to 2 yamahas, pc2602 and m2 to have the closest sound signature from the amps, driven by a philios preamp. I have heard the ar3a and LST togerher and that was amazing. However, the designated amp here for the LST is the 845 push pull mono blocs. I shall have a look around as far as the polyfill is concerned. Cheers

My bad... they are actually 160uH, so yes .16mF. Get confused always with the pico nano micro mili etc The gauge was actually my concern. The little coil adjacent is equally .16mH, could that also be used instead? I read about the gauge being responsible for characteristic AR sound... does it count for all drivers? I used 1.15mm now, closest i could find. I have refoamed the woofers. Today i make the final touch and will be stacking 2 pairs ar3a with only difference between them being the tweeters and rubber vs foam surround. Have tested individually and sound is great. Regarding the tweeters old style with 3 points of glue. I came across a youtube how to instruction film. That bloke removed the resonance damping and glued all around the gap. Would that be the way to go in order to revitalize dried out glue tweeters? I have 5 working tweeters in this state... Cheers

Q about the coils used... I am completely new to the tools and values here. What resistance should a 1.6mH coil have? Is it the wire thickness that dictates the outcome? I have 2 very different coils and both 1.6mH value both in size and resistance value, obviously gauge also. I measure 0.18R and 0.54R Any suggestions?

I have created the .16 coils. There is something unclear to me. In the improved schematic i see a series coil of 0.16mH value and parallel 0.1 coil. The first seems to be the one i have to add but its position is the same as in the ar3a schematic. The parallel seems the additional coil. I have not measured the original coils so forgive me if i seem stubborn but shouldnt i be adding .1 coil parallel? Obviously i cannot find an unlimited schematic anywhere... hence my confusion. What should be the value and postion of my additional coil? I have created the 2.6mH coil but in the improved scheme i see it working together with #4 which means there is only addition of mid freq by the woofer but no subtraction on the mid side. You mentioned this coil should preferably be reduced in value. Can i not compare these schematics to each other? Does anyone have the unlimited schematic so i can compare it to what i am building?

So what would be the height to position the cone? Is there way of determining what the correct height is?

"whenever possible). This method is especially advantageous for AR woofers with cones lower than the basket rim, as it allows you to manipulate the height of the cone during the gluing process." Roy Could you please explain what you mean with this? I have ordered a set with dustcaps and shims. It is the largest refoam job i am attempting so thought it would be a smart move to do it with shims. Until now i used clothes pegs. I am intrigued by your comment. I know from experience that horizontally storage of woofers ruins the spider but until now experienced nothing of that with vertically mountes vintage speakers. Also i wonder why i cannot find rubber surrounds anymore? I have 2 sets mounted on 4 12 inch woofers. One set being in very good shape since 2003 which pretty old by now. The other is of unkown age Cheers

Ok got it... The wait is for the right tools and parts now...

I still have to open up the improved speakers. I am curious to see what i will find. Driver types xo glue.... Too busy at the moment. Day after tomorrow i hooe to have the coils for the HiVi tweets...

Within the xo in series i have read that it does matter which way you implement the coil. Being the leadin on the outside of the coil or rather from the center outward. Parallel i can imagine different rule applies. But lacking foundation in education with the matter i have only fora and people like yourself to learn from. I wasnt aware it didnt matter and only popped the q to be sure it isnt installed wrong. I only vaguely remember stuff like cork screw rule... and was thinking with regard to what i read and induction being applied wrong it would render my coil useless... Im pretty much an intuitive kinda guy so pick up things taught along the way. Thank you for all your kind help. The first speaker is now playing with older style tweeter, no coil and basically resembles the frankenstein sonically at the moment. Tonegem mid and woofer in both and same era tweeter and xo. I have ordered an LCR multimeter so i can mesasure the coil for the newer tweeter. Also handy for the caps. Cheers

Thank you Roy... The filter of speaker #1 has been restored. I am making the coils .16 but have a question. Undocumented territory and my knowledge leave me in the dark how to hook uo the .16 coil. Correct would be from inside to out but what is in this case plus and minus. Plus being inside of the coil, is this simply how it is placed in the scheme? So according with schematic...

Roy, you are right, 35v is much too low as the Quad 303 almost already exceeds this. I shall buy this immediately. Let alone 260 watt yamaha 😁 About the resistors, there are 20 pieces in parallel with tweter and 20 with mid so yes that would make a 12,5R for each unit. Thank you for the effect explanation. As the limited drivers are used, i am aware there was an xo change to accomodate the Lpads, but can i simply place the pots? I happened to have some 1mm ,39 coils which i could unwind to ,16. I gather the cap is necessary, the coil could possibly be avoided with an original pot. The mid could be used as is with the original pot and adjust to taste, right? Unwinding 2,88 is possible or adding 1,0 to a number 7 and unwinding the 1,0 i think is best so to keep AR parts original, no? I presume unwinding will make the woofer louder? By all means, i am no expert and just an audio nutcase enthusiast of 57 years of age so any advice or help is greatly appreciated... Cheers

Woofer swap with rubber surround Tonegem and made the tweeter black again.

Thank you for your elaborate answer. I am just curious what the 20 * 300R parallel with the tweeter is for. (Similar addition for the mid speaker) I have not seen any AR so far with this nor any schematic. As for the sound, i find them very open and a bit harsh sounding. Like the pots are fully open. I tend to prefer the middle setting with most speakers ie LST. 3A Impr has a similar voicing signature as this ar3a and i cannot alter but a/b switch them, but not necessarily the AR6. Those are more balanced when the pot is opened up. Ar6 Sounds a bit muffled with the pot in the middle. The Frankenstein have the tweeter pot opened up but mid toned down and sound very closed in dirext comparison to my newly acquired 3a. So putting back the pots i will certainly do as i do not care for biwire and especially not for biamping. Bin there done that... Today i tried a Yamaha PC2602 on the 3a and pretty loud and they seem to push the ar3 effortlessly not breaking a sweat. No clipping. The Yamaha M2 i pushed into clipping to my surprise the other day. PC2602 is 2 * 400@4R btw. If it becomes too much it has a fan as backup. Actually next test will be the 2602 on the LST as that speaker is even harder to drive. Not sure yet which eventually will be used for the ar3a. Plenty of choice so takes time to match them perfectly, amp and speakers. Cheers

Discovered an addition in the xo which i hadnt noticed. There are 20 resistors placed parallel to the tweeter and also to the mid. Due to glue i am having trouble lifting the tweeter but the mid is a gold magnet version very much same as the woofer, so indeed Tonegem. Effectively if i am right about the color code it is the equivalent of 12.5R. How much does that attenuate? Or is there none? The mid and high seem full throttle. Yet a/b comparison with LST in position 3 is very little difference. Perhaps a little more sharp edged...

A quick look inside reveals the gold basket tonegem woofer. Ar3a xo with 1 deviation. Instead of 150uF 133uF has been applied. They are in fact ar3a speakers, the serial numbers are correct and the official import handler of Holland at the time provided all the upgrade drivers. So without looking i think it is correct to assume the drivers are all Tonegem. The bi-amp schematics found elsewhere in the forum has been used here. The bridge outside really divides the xo in 2 parts and it is safe to connect any 2 amps with the bridges removed. Cherry on the cake is that i have obtained the original 4 pots with the sale. As the pots are out the speakers simply blast out full on the mid/tweeters unattenuated. A bid had been made of 600 but as i was very early in negotiating i was lucky to take this find home for 400 including the pots. Someone say that the drivers alone were worth 400? 😁 Anyway, i am going to put in the Tonegem woofer with rubber surrounds and listen. I will revert the biamping with the two original pots later . Placing them on my original stands which i received yesterday by mail for 125. They will never depart my home again. The Frankensteins i am not yet certain about, but apart from the badge i do know now they come very close to each other in terms of drivers and xo. I am only wondering if i should add the remainder caps to obtain the value of 150uF or is the advice with these to woofers to leave as is...? The other are hooked up to new 150uF btw. If the latter then it means the 150uF of the Frankenstein should be altered too in case i decise to stack them at one point. Cheers

Why o why....? 😪 AR went down the same road of less quality and faster production techniques, cutting samecorners as i have seen in my days with Sansui. Vinyl vineer, glue, materials etc... How sad.

I have been able to get my hands on a set of original ar3a stands. I want to make some oak stands for the lst/ lst2 combo. Here is a preview what that will look like... I will follow the contours of the lst2 with solid oak, so it has to be cut twice at 45⁰ angle and glued together. Ofcourse the back will remain open as i dont want a resonating box underneath them.

Friend of mine has original unhassled ar11, i have the improved unhassled and sunday possibly the limited, if your deduction is correct, Roy. Maybe it will give more credibility to which schematic is more likely to be correct. I have still not yet found the time to open my improved. Cheers

Am i correct in saying that either the tweeter or mid is out of phase in the AR11 and AR3a improved? I always get lost in reading xo schematics... I am also correct in quoting someone in another forum that a dutch man was very much involved in the development of the 3a improved version and that it was never sold in the USA?

This is a set of AR6 i bought in Germany and i refoamed them myself. The case was empty and i added fiber glass. Thanks to RoyC i now know that i have to open them up and can add or subtract weight as he was kind enough to inform me of the needed volume/weight for this model. Also an Audyn 10uF cap was added. The set plays on a refurbished and modified Quad 303 and 33. The boards have been emptied and/or replaced by me and only the best modern equivalents low tolerance parts are used like metal film resistors, transistors, mkp caps etc... The mod is one that takes out the 4 ohm restriction which was inserted into the amp originally to not fry the Quad 57 electrostatic speakers as they had no overload protection and the impedance drop could ask too much current from the amp at 4 ohm frying the treble panels. It now delivers all the current it can give at 4 ohm and some may know 303 stands for 30 volts @ 3A. This was with 8 ohm btw, so for 4 ohm it will now give much more punch. All discrete stages... This combo sounds excellent! Very different to non-discrete hifi or tubes. Mellow i would call it.