Linear Tracking Tonearms

[MylesBAstor]

High-end audio seems to be filled with those products that offer the promise of exceptional performance but are held back by some flaw or another. Those products that you know in your heart can be fixed if given a little TLC. Then you find out after spending ages with that component that no matter what you do that issue will never be resolved.

One such product is linear tracking (air and mechanical). I'm sure that many of us here at one time or another (or still do) in their audio journey mounted a linear tracking arm on the turntable. Yes, in theory linear tracking arms offer the ultimate in LP playback. But in reality, linear tracking arms are held back many issues not the least of which include:

Movement and ability to maintain tangency to the groove
Solidity and low octave reproduction
Susceptibility to warp wow with short arms
High horizontal mass
Air flow issues
Machining issues eg. the best air bearings might have a 1/10,000 of an inch tolerance and finding a material that isn't susceptible to temperature fluctuation is challenging
Freedom of movement
Inability to maintain azimuth across the record
Setup can be frustrating

Yet, some of the best sound I've ever heard is from air bearing arms such as the now sadly discontinued Air Tangent tonearm. The arm's resolution, sense of spaciousness and soundstage were something to behold. But at the same time, the arm wasn't the equal of a pivoted arm when it came to reproduction of the lowest octaves. The of course, there's the issue of convenience. After a while, who wants to hassle with air compressors, filters, tubing running everywhere in the room. Especially in smaller apartment quarters as opposed to someone with a house who could put the compressor in another room, garage or basement.

But honestly, I do miss listening to those arms and sometimes I ponder putting a linear tracking in addition to a pivoted arm on my turntable. Maybe one day.

[MylesBAstor]

Three products that put linear tracking arms on the map!

The Dennesen tonearm. Frank was a brilliant designer. Decades ago, he also made a speaker with an Estat tweeter that was interesting. Sadly, he disappeared and no one seems to know what became of him. Alan Sliski, one of the air bearing tonearm's co-designers and original patent holders (along with Jacob Rabinow) used to lurk around WBF forum and in one of those small world stories. One of the beauties of the arm was the ability to adjust for VTA back in those days.

"Yes Alan is one of the original patent holders of the air bearing tone arm. Alan and I happened to meet purely coincidentally through non-audio work about 15 years ago (he was developing a minaturized low energy X-ray machine for treating cancer for Photoelectron Corp in Boston and my group at NYMC was doing the biology). The story of how we met though is amusing though. I was sitting in the company's dining facilities and noticed all these exquisitely restored vintage audio components like a Scott tuner sitting in the room. Immediately my high end radar went off and I asked my host who that equipment belonged to? My host then proceeded to introduce me to Alan and we hit it off immediately. Interestingly we lost touch after I left academics and we rehooked up here courtesy of WBF."

Alan's an inveterate inventor and physicist and last we spoke, he still had a garage full of the parts to make the ABLT-1 tonearm. Just if anyone was curious.



The Rabco (and many modded versions), predecessor of the Goldmund arm



The Souther tonearm eventually purchased by Clearaudio. This arm sounded wonderful in its day, despite it's issues, on the VPI HW-19 of the day. Always had to slightly tilt the arm so the cartridge moved smoothly. Always had to also remember to move the cartridge to the rest position before tilting the arm up to remove the record. Othewise, the cartridge would just slam into the start position. Not recommended!



The Coloney (Lew Eckerdt and Bruce Thigpen). Later became the Mapleknoll and later morphed into the Eminent Technology arm. The ET might be the most widely used linear air bearing arm of its day. It didn't in its day cost an arm and a leg and the sound could be quite good.

[MylesBAstor]

Some of my other favorite linear tracking arms of the day.

My favorite of all time by Leif Haggemark. The Air Tangent cost a then unheard of--in the '90s-- $12,000 when it first came out ($15K with remote control VTA). Different wands were available for different cartridges.







Andy Payor's Rockport arm. Audiophiles still ask Andy to reconsider his decision to halt making turntables.









The Forsell. Nice arm but sometimes doubled as a water fountain until the water filter was incorporated.








Rockport again








Mapleknoll arm. Predecessor of ET arm.







John Bicht's Versa Dynamics table and arm. Note the shorter tonearm length here.







The Eminent Technology 2 brought the air bearing technology to the audio masses. It's performance could be improved with a few tweaks such as pumps, surge tanks, stiffness of counterweight arm, etc. What particularly ingenious thing about the ET2 was the eccentric cam height adjustment mechanism; ergo the stylus remained in the same position when raising or lowering the arm.







Finally, the King of Harry Pearson's hill for many years. The Goldmund Reference turntable arm and table. Yes it looks like a Rabco arm.

[MylesBAstor]

Linear tracking arms continue to be manufactured and sold today. A quick search of the internet reveals many real, weird and downright bizarre looking DIY type arms. Among the commercial arms on the market today:

Kuzma





Clearaudio






Walker Audio (direct descendant of the Mapleknoll table)







Bergmann Magne





And an intriguing arm from Consonance made in China

[MylesBAstor]

Opus 3 displayed a turntable a decade or two ago at CES but never knew they made a linear tracking arm. Or at least a prototype?

[MylesBAstor]

Then there was this prototype of a Goldmund arm. Have no idea if ever made it into production. Goldmund had reportedly started producing a new limited edition table but there's no mention of anything analog on their website.

[MylesBAstor]

Some of the more creative approaches.

[MylesBAstor]

Never saw this Rabco setup.

[MylesBAstor]

Was/is the London Decca Reference Air Bearing arm a real product?

[MylesBAstor]

[Audiocrack]

Thanks Myles for this nice overview with great pictures. Owning the Kuzma air line tonearm and having the Walker and Forsell tables (never had to deal with a Forsell fountain) with their own arms available I suppose you can call the lineair tracker my favourite tonearm.

Btw, did/do you like the Forsell turntable?

[Rob]

High-end audio seems to be filled with those products that offer the promise of exceptional performance but are held back by some flaw or another. Those products that you know in your heart can be fixed if given a little TLC. Then you find out after spending ages with that component that no matter what you do that issue will never be resolved.

One such product is linear tracking (air and mechanical). I'm sure that many of us here at one time or another (or still do) in their audio journey mounted a linear tracking arm on the turntable. Yes, in theory linear tracking arms offer the ultimate in LP playback. But in reality, linear tracking arms are held back many issues not the least of which include:

Movement and ability to maintain tangency to the groove
Solidity and low octave reproduction
Susceptibility to warp wow with short arms
High horizontal mass
Air flow issues
Machining issues eg. the best air bearings might have a 1/10,000 of an inch tolerance and finding a material that isn't susceptible to temperature fluctuation is challenging
Freedom of movement
Inability to maintain azimuth across the record
Setup can be frustrating

Yet, some of the best sound I've ever heard is from air bearing arms such as the now sadly discontinued Air Tangent tonearm. The arm's resolution, sense of spaciousness and soundstage were something to behold. But at the same time, the arm wasn't the equal of a pivoted arm when it came to reproduction of the lowest octaves. The of course, there's the issue of convenience. After a while, who wants to hassle with air compressors, filters, tubing running everywhere in the room. Especially in smaller apartment quarters as opposed to someone with a house who could put the compressor in another room, garage or basement.

But honestly, I do miss listening to those arms and sometimes I ponder putting a linear tracking in addition to a pivoted arm on my turntable. Maybe one day.

your intro kinda reads like a blanket condemnation of linear trackers and air bearings in particular. you know you want one, you know YOU NEED ONE your bullet points remind me of: "why I don't date hot women with big knockers." what could possibly be wrong with that? I could have written that list for every time I dumped one of these arms for a pivioted type. We can justify our decisions anyway we want at the end of the day the proof is in the pudding and Id say you need to revisit some of the best examples of the breed, and IMHO The Air tangent was not the final word but a harbinger of better designs to follow. And not all air bearings are created equal - far from it. The vast majority were porous type designs with relatively low tollerances as opposed to annular bearings (important) which are found in only two 'arms to ever hit the market, Versa and Rockport. IMO, most of the points you make have been overcome and the others are par for the course which shouldn't be a hurdle for anyone reading this forum.

This is another air bearing linear tracker by Simon Yorke:

[MylesBAstor]

I thought my last line is that I miss linear tracking arms. Yes I could see trying a Bergmann arm down the road.

But there's the convenience factor especially in an apt. and where to put a compressor? Granted newer compressors are quieter, they also seem to take up more room to damp the noise. No matter what in the old days, the compressors were noisy and always made their presence known in an apt.

[Rob]

Myles, I'm agreeing with you your closing remark ties it back to your point its the quasi historical view above that I'm referring to.

[MylesBAstor]

Got it.

[kcin]

I haven't had the experience with SOTA designs. I've used the Eminent Technology and the Mapleknoll - I think on the Apollo model -one of the last ones made before they folded. I've also used the Goldmund T3F.

Some one locally has a ClearAudio/Souther, Kuzma and one other that I don't recall- I have 2nd hand experience with those.

Linear trackers are a whole other commitment to the hobby as they require a real good knowledge of mechanics and technology. None of them have ever been "set and forget" , if that is even possible in analog.

I have pulled my hair out on most of the aforementioned in order to get them to work and keep them working. Some never ended up working as intended ( Goldmund) .

I share the passion and I totally get why we would have these in our system- and as crazy as I am for some of this stuff- even I have to step back and say a pivoted arm will be my compromise. Just way too much commitment based on the ones I have experienced for me now. I just don't have the time to deal with them based on my past experience.

I still get called over several times a year to a fellow 'phile's home to kickstart his Mapleknoll arm.

I am sure some of the best designs have made things simpler now.

[david k]

Great thread and a nice collection of images Myles! As entertaining as this thread is it's also a reminder why I don't mess with linear trackers anymore as a result my Goldmund Reference has been silent for the past 6 years since our move but this thread is really tempting me to jump in and deal with it !

david

[Joe Pittman]

Way back when, I had a Rabco then later a couple of versions of the B&O 4002 (I have a copy of B&O's white paper on the design which is very compelling). Then I switched to pivoted arms and never went back. I've been tempted to try linear trackers again, but like kcin, just don't have the time and for me, the necessary commitment. I salute those who use linear trackers on a daily basis. I really enjoyed listening to Mike Lavigne's Rockport when he had it and another friends Forcell (which sounded amazing at times).