Hi all. Looking for recommendations on who can restore a pair of AR3 speakers. I live in Tucson AZ and I'm not really a DIYer, but thought I could get some useful advice. Tweeters, mid-range and woofers all work, and in spite of their age the foam on the woofers have no visible cracks and still seem pliable (one woofer was replaced about 25 years ago). Some pitches seem to jump out almost as if they were triggering a sympathetic vibration somewhere, especially in the octave just below middle c. I'm sure the speakers are far out of spec after all these years because the sound is muddy and in general not what it used to be.
RVILS
RVILS
That takes us into the bass region so its worth examining the bass speakers closely.
Could it be as simple as their mounting screws needing tightening up? Probably not!
Does the 'sympathetic vibration' occur equally on both speakers?
Years ago, decades actually; there was a series of articles on this exact subject in "Speaker Builder" magazine back when it was still known by that name. I think the guy's last name was Yeago. I remember this simply because I worked with a guy with that same last name. He saw the cover one time and commented he couldn't believe they had the same last names.
If it were me; personally, I wouldn't bother with the original drivers or crossover. Why not totally upgrade entirely??? Technology has come a long way since the 60's and 70's. There are literally dozens of drivers available that will fit the existing box, cut outs, etc. and WAY out perform the originals. My 2 cents worth. If you are SERIOUS about restoration (like a vintage or classic car for instance); see if you can get the complete "Speaker Builder" papers on the rebuilding of the AR3A)...
Best of luck either way!
Yep; understand. There ARE some woofers (that will FIT that box) out there with fs BELOW 20 Hz; I have had some myself. If the goal is to be perfectly, 100% restored; more power to you. If you can confirm FOR SURE that all drivers are in good working order; there may be hope.
One of my buddies had a pair of AR's; not sure of the model number. They were 10 inch 2-way. The foam surrounds were totally dry rotted. We just put in some basic, $25 Pioneer 10 inch woofers and he said that they totally blew away the originals. So; make of that what you will.
That takes us into the bass region so its worth examining the bass speakers closely.
Could it be as simple as their mounting screws needing tightening up? Probably not!
Does the 'sympathetic vibration' occur equally on both speakers?
Yes, so it's not literally sympathetic vibration. Seems more like unevenness across the sonic spectrum.
If it were me; personally, I wouldn't bother with the original drivers or crossover. Why not totally upgrade entirely??? Technology has come a long way since the 60's and 70's. There are literally dozens of drivers available that will fit the existing box, cut outs, etc. and WAY out perform the originals. My 2 cents worth. If you are SERIOUS about restoration (like a vintage or classic car for instance); see if you can get the complete "Speaker Builder" papers on the rebuilding of the AR3A)...
Best of luck either way![/QUOTE]
Thank you for your"2 cents worth." This is exactly the kind of input I'm looking for as I decide which way to go.
Best of luck either way![/QUOTE]
Thank you for your"2 cents worth." This is exactly the kind of input I'm looking for as I decide which way to go.
The 12" woofer had a free air resonance between 15 and 19Hz which did not go above 46Hz when mounted in the air suspension enclosure.
Substitute 'normal' woofers and you don't have an AR-3![/QUOTE]
Thank you, I did not know that. I'm not committed to 100% AR-3 purity, I just want great sounding speakers, and if these can be returned to the quality they once had (or better) for a reasonable $, great, even if not "pure." Or it may make more sense to just shop around for new speakers. That's the decision I'll be making with help from the forum.
Substitute 'normal' woofers and you don't have an AR-3![/QUOTE]
Thank you, I did not know that. I'm not committed to 100% AR-3 purity, I just want great sounding speakers, and if these can be returned to the quality they once had (or better) for a reasonable $, great, even if not "pure." Or it may make more sense to just shop around for new speakers. That's the decision I'll be making with help from the forum.
I make of that that the perished foam surrounds on the originals were leaky and the air suspension was no longer working!
To back up oldspkrguy's suggestion, here's a promising replacement 12" air suspension woofer. Quite pricey though!
https://www.madisoundspeakerstore.com/approx-12-subwoofers/sb-acoustics-sb34swpl-76-4-12-subwoofer
It has a free air resonance of 18Hz and a Qts of 0.33.
https://www.madisoundspeakerstore.com/approx-12-subwoofers/sb-acoustics-sb34swpl-76-4-12-subwoofer
It has a free air resonance of 18Hz and a Qts of 0.33.
Acoustic Research AR-3 Speakers | Sound & Vision
Just found this. Do you have the AR3 or the AR3a? According to this; the woofer was the same but the mid and tweeter were improved with the 3a. There are sometimes used AR drivers and parts for sale online; ebay and others.
Replacement Advent and Acoustic Research Speakers and Parts
These people say they have genuine AR3a woofers!
Acoustic Research AR-3a Specifications:
Drive Units: 305 mm (12 in) acoustic suspension woofer, 38 mm (1 1/2 in) midrange hemispherical dome, 199 mm (3/4 in) high-frequency hemispherical dome.
Crossover: 575 Hz, 5000 Hz
Impedance: 4 ohms nominal
Controls: Midrange and high-frequency driver level controls
Amplifier: Up to 100 watts per channel
Size: 356 x 636 x 289 mm deep ( 14 x 25 x 11 3/8 in)
Weight: 24 kg (53 lb)
Woofer resonance: Free air 18 Hz, in enclosure 42 Hz
Volume of enclosure: 48.2 litres (1.7 cu ft)
Found these above specs for the 3a
Just found this. Do you have the AR3 or the AR3a? According to this; the woofer was the same but the mid and tweeter were improved with the 3a. There are sometimes used AR drivers and parts for sale online; ebay and others.
Replacement Advent and Acoustic Research Speakers and Parts
These people say they have genuine AR3a woofers!
Acoustic Research AR-3a Specifications:
Drive Units: 305 mm (12 in) acoustic suspension woofer, 38 mm (1 1/2 in) midrange hemispherical dome, 199 mm (3/4 in) high-frequency hemispherical dome.
Crossover: 575 Hz, 5000 Hz
Impedance: 4 ohms nominal
Controls: Midrange and high-frequency driver level controls
Amplifier: Up to 100 watts per channel
Size: 356 x 636 x 289 mm deep ( 14 x 25 x 11 3/8 in)
Weight: 24 kg (53 lb)
Woofer resonance: Free air 18 Hz, in enclosure 42 Hz
Volume of enclosure: 48.2 litres (1.7 cu ft)
Found these above specs for the 3a
I make of that that the perished foam surrounds on the originals were leaky and the air suspension was no longer working!
Yep, obviously. My point was that a cheap woofer that was 20 years newer fit right in and out performed the original. I'm sure the TSP's were not the same but he was totally satisfied.
Lots of options; depends on far from 100% original one would be willing to go!
Something as simple as updating the old capacitors in the crossover circuit could bring the sound back to life.
The versions of the AR-3 crossover circuit shown in the attachment contain 6uF and 24uF non-polar (NP) capacitors.
However, here's something simple to try first:
The level controls may be making intermittent contact, especially when vibrated by the music. Try turning them through their full range several times to see if that cleans them up.
If this makes a difference, but only temporarily, replacement of the level controls would be on the cards
Attachments
You need to search on the Classic Speaker Pages. There are a number of people there who know what they are talking about. I would look for Tom Tyson. He is the official AR historian.
The level controls on the speakers are the most common problem. They get corroded and then become intermittent.
The next most common problem is that the ferrofluid in the midrange and tweeter has dried up and this adds massive frictional damping to them which gives each a Q of around 0.1.
The caps might be bad, but I really doubt it.
It will not be easy finding drivers that drop fit into the cabinets to work within the system. The high crossover frequencies and very low impedance, make the system a bit difficult to modify.
There is a company called AB Tech Services, which used to be run by Alex Barsotti, who is an ex AR employee. The link for the company is below.
Distributor for all Acoustic Research (AR), Advent, Hoverboard, Smartwatch, Search Engine, Furniture and Jensen Parts
They are the official place for AR replacement drivers and parts.
The level controls on the speakers are the most common problem. They get corroded and then become intermittent.
The next most common problem is that the ferrofluid in the midrange and tweeter has dried up and this adds massive frictional damping to them which gives each a Q of around 0.1.
The caps might be bad, but I really doubt it.
It will not be easy finding drivers that drop fit into the cabinets to work within the system. The high crossover frequencies and very low impedance, make the system a bit difficult to modify.
There is a company called AB Tech Services, which used to be run by Alex Barsotti, who is an ex AR employee. The link for the company is below.
Distributor for all Acoustic Research (AR), Advent, Hoverboard, Smartwatch, Search Engine, Furniture and Jensen Parts
They are the official place for AR replacement drivers and parts.
Everyone is making good points here. I wasn't aware they used ferro fluid back in those days. You can buy ferro fluid but the next question is can you SAFELY (i e non-destructive!!!) disassemble the mid. and tweeter drivers to the point where you could replace this?
Try spraying the level controls with CAIG De-Oxit; then rotate several times; repeat if needed. One of my other buddies also said he had some AR's; he said the level controls were wire wound pots and NOT actual L-pads (not sure if that is true or not).
Many people sell re-foam surround kits; see the links I posted earlier.
Electrolytics do dry out; especially in power supply and amplifier circuits; etc. It would be a simple thing to temporarily cut one lead of each capacitor then use clip leads to connect newer caps in their place. In my case of an old amplifier; when the electrolytics were old enough; every now and then I would hear funny clicking, scratching, "wooshing" sounds. Obviously, cross over caps are used in a passive circuit so maybe this is not a good comparison. Many people sell inexpensive cross over capacitors; maybe you could try the Audyn "Q4" for starters; Parts Express and Meniscus both stock these. They are inexpensive and come in a very wide range of capacitance values. They sound good too for the money.
Again, see if you can get the complete re-build of the AR3a from Speaker Builder magazine. His write up went into at least 3, maybe 4 or more issues so it was quite extensive.
I would also call the vendor I posted the link to earlier that say they have "original AR3a" woofers. Quiz them; ask a lot of questions (don't just take their word for it; who? makes them and where?; can they send you verifiable, 3rd party test and evaluation results?, etc...).
If you are thinking of a new woofer; look over the specs of Scan Speak and SB Acoustics for starters; many of their woofers share the same design Engineers and most of them have a VERY low fs. Many of them can do really deep bass in smaller, closed boxes. The TSP's may not exactly match but they would still work OK. The design and build of these brands is world class for sure.
And, on the SB Acoustics website; under the heading "coming soon"; they have a new dome midrange. This is in the Satori line; their premium line of drivers. I have no clue at the moment (without digging much deeper) about the physical size, TSP's, etc. I do have a few Satori mid-bass; again, true world class drivers at a reasonable price.
My latest project, in fact, is using a SB 29...woofer. It is shown as 10 inch but really closer to 11 inch. I am getting an f3 about 37Hz in a closed box of 1.2 ft^3 (33 liters)!!! (I should add; this is without ANY EQ or bass boost; honest, deep bass). The SB sub-woofers CAN and ARE used as woofers; not limited to just the lowest octaves; many people have reported very good results even though they are called "sub-woofers". I have an SB23... sub, about 9 inch; it can be used all the way up to 800 Hz no worries! It is in a small closed box; with a plate amp and EQ, it goes as low as 14 Hz flat, in room!!!
So, just more 2 cents worth..."oldspkrguy" is for old speaker guy (obviously). I heard my first AR3a's before I had my drivers permit; I am now in my mid 60's (do the math ha ha ha)...
Cheers and best of luck!
Try spraying the level controls with CAIG De-Oxit; then rotate several times; repeat if needed. One of my other buddies also said he had some AR's; he said the level controls were wire wound pots and NOT actual L-pads (not sure if that is true or not).
Many people sell re-foam surround kits; see the links I posted earlier.
Electrolytics do dry out; especially in power supply and amplifier circuits; etc. It would be a simple thing to temporarily cut one lead of each capacitor then use clip leads to connect newer caps in their place. In my case of an old amplifier; when the electrolytics were old enough; every now and then I would hear funny clicking, scratching, "wooshing" sounds. Obviously, cross over caps are used in a passive circuit so maybe this is not a good comparison. Many people sell inexpensive cross over capacitors; maybe you could try the Audyn "Q4" for starters; Parts Express and Meniscus both stock these. They are inexpensive and come in a very wide range of capacitance values. They sound good too for the money.
Again, see if you can get the complete re-build of the AR3a from Speaker Builder magazine. His write up went into at least 3, maybe 4 or more issues so it was quite extensive.
I would also call the vendor I posted the link to earlier that say they have "original AR3a" woofers. Quiz them; ask a lot of questions (don't just take their word for it; who? makes them and where?; can they send you verifiable, 3rd party test and evaluation results?, etc...).
If you are thinking of a new woofer; look over the specs of Scan Speak and SB Acoustics for starters; many of their woofers share the same design Engineers and most of them have a VERY low fs. Many of them can do really deep bass in smaller, closed boxes. The TSP's may not exactly match but they would still work OK. The design and build of these brands is world class for sure.
And, on the SB Acoustics website; under the heading "coming soon"; they have a new dome midrange. This is in the Satori line; their premium line of drivers. I have no clue at the moment (without digging much deeper) about the physical size, TSP's, etc. I do have a few Satori mid-bass; again, true world class drivers at a reasonable price.
My latest project, in fact, is using a SB 29...woofer. It is shown as 10 inch but really closer to 11 inch. I am getting an f3 about 37Hz in a closed box of 1.2 ft^3 (33 liters)!!! (I should add; this is without ANY EQ or bass boost; honest, deep bass). The SB sub-woofers CAN and ARE used as woofers; not limited to just the lowest octaves; many people have reported very good results even though they are called "sub-woofers". I have an SB23... sub, about 9 inch; it can be used all the way up to 800 Hz no worries! It is in a small closed box; with a plate amp and EQ, it goes as low as 14 Hz flat, in room!!!
So, just more 2 cents worth..."oldspkrguy" is for old speaker guy (obviously). I heard my first AR3a's before I had my drivers permit; I am now in my mid 60's (do the math ha ha ha)...
Cheers and best of luck!
Ferrofluid is a fairly modern innovation. It was first introduced to tweeters in the early 1990s, so will not be found in the AR-3.
Vintage speakers from the likes of Wharfedale and AR used simple potentiometer controls. Although Wharfedale used a constant impedance volume control (the 'Truqual') in their radio extension speakers, the modern form of L-Pad control was yet to be realised.
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