Author: David Hoehl - TNT USA
Published: March, 2018
In the few days since Part II of this series appeared, I've had some extensive correspondence with two Lenco turntable enthusiasts, Jon Sadler in New Zealand and Tuomas Hakuri in Finland. Jon and Tuomas very kindly sent a rich trove of information about Lenco tables and links to sites where more is available to the curious and the enthusiast alike. Ordinarily, such an exchange would appear in the Readers' Feedback section of letters received in the TNT mailbox, but after a brief consultation our editor and I decided this one would best be adapted into a supplementary article, both to give the content more permanence and to present it in a more organized fashion than as a string of letters. For the most part, I'll try to stay close to quoting what Jon and Tuomas sent me, merely applying the odd adjustment for continuity as necessary.
Tonearms. Tuomas, whose hobby is rebuilding turntables, offered some detailed information about those troublesome Lenco tonearms. As you may recall, I wrote of how the ones I'd encountered tracked very poorly. Given that my experience with Lenco tables mostly predated the Internet, I had no way of knowing "as found" Lenco arms would need any more attention than, say, the arm on your average garage sale Dual. While admitting "the beauty of a Lenco is in its drive system, not so much in the tonearms," Tuomas explains how Lenco arms can easily be put right. He writes:
The main problem with these arms (L70 and L75), also the main difference compared to many other arms, is that both L70 and L75 type have parts that either deteriorate or freeze over time. So these arms, especially the L75, often need to be serviced before the turntable can be used. In both arms' cases the problem is usually easily solved and with the correct fix likely won't appear again.
The L70 arm has a tracking force adjuster with a threaded bar. That bar tends to oxidize and to get stuck preventing correct VTF adjustment. Also, the upper pivot bearing cavities are filled with grease that becomes hard and dirty over time. This is probably not a problem any more than in any other arm with greased bearings, though. Also, in some cases the bearing racks have been damaged for one reason or another. The arm is heavy-ish and clumsy-ish, being a 60 year old design, but it's really rather well designed and not as heavy as it looks. People have used upper-medium compliant cartridges with ~1,5 grams of VTF with the arm, apparently with some success. Maybe not recommended, but this anyway shows that the arms is rather capable.
L75 arm on the other hand has a rather interesting plastic/rubber knife-edge bearing design that has its own problems. The most apparent problem is that the original material – some kind of plastic – is usually totally deteriorated at this point. V block material was later changed to rubber, those are still often in good shape. Luckily the V blocks are removable and relatively easy to replace. Moreover, there are a wide variety of aftermarket V blocks available. Materials range from original type rubber to hard plastic and brass. The latter types probably have unlimited lifetime. Some early L75 arms do not have V blocks but V cuts in the arm pillar wall. Those ones don't deteriorate like the earlier V blocks, but if there's damage it's also more difficult to fix.
The L75 arm also has decoupled counterweight which tends to sag a bit. This is not a real problem if the sagging is not exessive.
Both L70 and L75 arms have similar type of arm pillar ball bearings that can be adjusted to very tight tolerances and are rather good. Even if the spring balanced arm and the knife-edge bearing arm might not be the best tonearm designs there are, they are not really bad either if they are just serviced and set correctly.
Lenco produced also one state-of-the-art tonearm that was installed to the L77 turntable or sold separately with model name P77. L77 was produced only for a short time and was essentially an L70 with the P77 arm. Both are rare and expensive. The P77 arm can be had for ~500-1000 euros and installed to any idler Lenco, although some minor top plate modifying is required. The P77 is heavier arm than the L75 arm, though, so that needs to be taken into consideration.
There are even aftermarket armtubes for the L75 arm, with sandwiched aluminium – carbon fibre tube design and a selection of headshell types. With those tubes, using the original bearing type, the arm can perform exeptionally well even with high-compliance cartridges. Even the stock arm should handle upper-medium and lower-high compliance cartridges just fine.
Especially to the point for this series of articles, Tuomas adds, "The L70 tonearm is considered very good for 78 rpm records. Apparently that arm is also very resistant to record warps etc. because of the spring balancing. This is only hearsay though."
I also noted Lenco arms take nonstandard headshells which may be hard to find and which I mistakenly described as being made of steel. Again, Tuomas elaborates: "The headshells, by the way, are not steel but aluminium. L75 arm is often thought to be a heavy mass arm but it's more like medium-mass arm."
Drive system. Tuomas also elaborated on rumble in the Lenco drive design and how to correct it.
The whole drive system is very quiet yet powerful when serviced, but servicing it requires some understanding of how it's supposed to work, maybe more than in most other idler tables.
Rumbling of a Lenco is usually a problem of an unserviced table, and in most cases it's not so difficult to get rid of it. One exception though: the plastic wheels of L70 and other early tables rumble no matter what. Better aftermarket replacements are available for not a huge price. The later aluminium wheels with rubber tires are very good when serviced, and usually replacing them is unnecessary. If you buy a new wheel for your Lenco, mind that the wheel axle diameters vary.
I have had several types of Lencos in my personal use, including a GL59 (early L70) and a few L75s. At the moment I use an L78, which is essentially an L75 with autostop function. None of my tables had any rumble issues except the GL59 that had original plastic idler wheel. The rumble level with that one was also low enough not to be a real nuisance. When using my current L78 (with original metal-rubber wheel) I can hear very quiet rumbling if I listen with headphones and there's a completely silent passage on the record. The rumbling gets buried immediately when any sound appears. I can't hear it through speakers at all, with any volume.
I've never been terribly concerned with how long a turntable takes to come up to speed, but I gather it's an issue for at least those accustomed to the nearly instantaneous starts of direct drive models. In discussing the Lenco mechanism, Tuomas touched briefly on the subject: "Speedup time to 33 rpm has been around 1 or 2 seconds with most of my tables with metal wheels, to 78 rpm maybe two or three seconds more."
Tuomas and Jon both offered links to helpful resources regarding Lenco (and even some other) turntables. Specifically:
Lencoheaven.net is the playground and support area for all things Lenco, including Mono reproduction and 78 play.
Main Site: www.lencoheaven.net
Mono (named after the moderator, sadly deceased)
If you are yourself a DIY type, there's a section called "Lenco Guides" on the Lenco Heaven forum main page. That section contains about all the information one needs when servicing and setting up pretty much any idler driven Lenco.
For example, this one is for taking apart the L70 arm
Usually it's enough to get the VTF adjuster to move (no dissembling needed), using some penetrating oil, for example, but in the example arm's case the vertical bearing racks are broken and further work is needed.
And this is for the L75 arm V blocks
Tuomas offers these final thoughts about Lenco in its stock form:
Lencos are often subject to massive updating, including heavy plinth, maybe new tonearm, new bearing, new top plate (PTP) etc... Those all are real updates, but it doesn't mean that a stock Lenco would be a bad turntable... people just love to tinker with them because it's relatively easy and often rewarding in one way or another (including psychological). So, to say - like many people like to say - that you can't get a decent TT out of a Lenco without massive/expensive work is not true in my opinion. It's maybe not high-end, but definitely not a bad turntable either, given that it's serviced properly.
This child of the 1960s never ceases to marvel at how much smaller the world has become since his youth, which, come to think of it, conincided with much of Lenco's heyday. Back then, in the days of paper letters mailed in envelopes and premium charges for even domestic long distance calls, the thought three audio enthusiasts in Finland, New Zealand, and the United States could engage in a rapid exchange about a Swiss turntable written up in an Italian magazine--well, it was the stuff of science fiction. Jon and Tuomas have my thanks for taking the time and having the passion to educate us about Lenco turntables; I think both my understanding and my opinion of these classics--which, to be fair, already made my "A list" for playing 78s--are much improved as a result. If I still stand by my own preference for the Strathclyde STD 305D, nonetheless I'll let my two correspondents have the last word(s).
Tuomas: "I fix turntables as a hobby, and in my opinion Lencos are by far the most delightful ones to play with. This is because of the overall build quality, straightforwardness of design, and results that can be gotten with just basic servicing."
Jon: "It's my belief they are amongst the very best players in the world (I would say that; I've built 8 turntables with them)."
Fast forward to Part III
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