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Dual 601 Belt-Drive Turntable Repair & Review

The classic Dual 601 turntable isn’t as well-known as contemporaries from Thorens and Rega, but it is a great turntable.

Features

The Dual 601 is a lovely belt-drive deck and offers quite a bit that other contemporaries don’t in terms of deck automation, vernier speed adjustment and noise isolation.

I should note that these decks are reasonably maintenance heavy, so they may not be the best choice for someone who wants to play records and just forget about getting their turntable serviced.

Specifications

Courtesy the Vinyl Engine

Drive: 8-pole Dual synchronous motor with precision flat belt to platter base

Starting time: approx 2 seconds to 33 1/3rpm

Platter: 305mm, 1.3kg, non-magnetic

Speeds: 33 1/3 and 45rpm

Pitch control variation: one semitone (6%)

Speed control: illuminated stroboscope

Wow and flutter: < 0.08%

Rumble: >63dB weighted

Tonearm: torsion-resistant tubular aluminium in self-adjusting pivot bearing

Dimensions: 420 x 148 x 365mm

Weight: 7.6kg

Common Problems

The Dual 601 has a very common problem, whereby the tonearm doesn’t return properly at the end of a record. Automatic decks such as the 601 typically have complex mechanisms to return the tonearm to its resting point and wear and degradation of these mechanisms is to blame for the strange behaviour.

In this case and with Dual decks, a small rubber ‘button’ wears out and perishes, falling off the small lever it is originally attached to. This, in turn, causes the arm to not be grabbed by the return mechanism and therefore not return to its rest point. This problem is resolvable, once you know what to look for and how to repair it. I have a few pics here of the deck in various stages of disassembly.

I’ve described a similar issue and repair of another Dual 601 here.

Once inside, there are numerous lubrication points and adjustments to be made. It is very important to use the correct lubricant at each lubrication point and not to skimp on this time-consuming step. The factory service manual actually specifies five or six different lubricants and I have modern equivalents for these here in the workshop.

This Dual 601 needed the very typical deep clean and service including spindle bearing maintenance, fresh synthetic oil, greasing and oiling of various other points and a few small adjustments before receiving an exterior clean and calibration of the tonearm and cartridge alignment.

Results

Once this work was complete, this Dual 601 ran and played records absolutely beautifully. A few images describing some of these steps follow.

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So here she is, sub-platter removed, showing the layout of the deck. You can see the central spindle bearing, speed change mechanism near the speed change lever and the tone-arm arrangement.
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The first job is to remove the turntable mechanism from the chassis.
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Some detail on the tone-arm stylus pressure adjustment. Note that this design utilizes a spring to provide the down-force, as opposed to a counterweight in other decks. Here the counterweight is set to achieve a zero-balance, with the spring doing the rest.
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Speed change mechanism detail…
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Here we see the underside of the deck, with main orange cam which controls the deck function. The motor is situated at the bottom-right, arm return mechanism is at the top-left.
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The control cam in more detail. this needs to be cleaned and carefully greased.
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And this is the dreaded arm-return mechanism. this causes problems on basically all of these decks, but it is easily remedied.
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After reassembly, we are playing a test record and checking for auto-return functionality.
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And here she is, all serviced, repaired and good to go!

Dual 601 Belt-Drive Turntable

$500 - $1200 AUD
7.7

Build/finish

8.0/10

Features

9.0/10

Sound quality

7.5/10

Scalability

7.0/10

Bang-per-buck

7.0/10

Pros

  • Solid metal and wood build
  • Servicability
  • Heavy flywheel and platter
  • Good sound quality

Cons

  • Quirky design aspects, including headshell
  • Low-mass arm limits cartridge options
  • Maintenance needed reasonably frequently

14 thoughts on “Dual 601 Belt-Drive Turntable Repair & Review”

    1. Hi John, the 601, like many other Duals, uses three screws which hold the deck to the chassis. These must be loosened and moved out the slot they sit in to release the deck. Be very careful, it’s very easy to make one of these much worse if you don’t know what you are doing. These Dual decks are mechanically complex, you need several types and grades of lubricants and there are many points to lubricate and/or adjust.

    1. Hi, the first thing I suggest you do is search for a manual, that way you’ll be able to get your head around the sometimes slightly unusual Dual control layout on these older decks. Speed switching on Duals is on the left. Also, have your deck thoroughly serviced if it hasn’t been done in a few years, these mechanical decks absolutely thrive on regular maintenance and were designed to receive it.

    1. Hi Duncan, there’s no VTA adjustment via tonearm settings, but some adjustment can be made via the mat, careful choice of cartridge and headshell spacers. Setup and mechanical state of service are critical with these machines. They are good decks but more maintenance intensive than many others and the Dual headshell/cartridge mounting system is prone to causing trouble, so be very careful with that part of the machine.

  1. John, I recently acquired a brand new 601 in a sealed box for 40 years or so. Everything works but the auto start and auto return. I assume the lube dried out after decades of sitting in a box. Follow your guidelines noted above?
    Thanks,
    Bob

    1. Hi Bob, it’s Mike and very nice acquisition there. The deck will need a complete service to resolve the lubricant issues and shouldn’t be used until that happens. The article is a great starting point but it’s not a tutorial and there’s a ton of detail I couldn’t include. You’ll need various lubricants, solvents etc and in most cases this would be a job for a specialist familiar with these machines but if you feel like having a go, be careful and best of luck!

    1. Hi Bob and no problem! I suggest referencing the service manual for this and other technical information. From memory it’s well written and contains the necessary diagrams, recommended lubricants, tools, adjustments and so on. This saves me a ton of time re-writing, summarising etc!

  2. Thanks for the help with the arm return! I was a little frustrated that you weren’t a bit more specific on the photo but I ran my mechanism manually a few times while watching all the things that happened and figured it out. I stuck a short piece of tubing over the whole standoff that the rubber dimmaphlochy was mounted on. It works perfectly now. Best of all, I didn’t break anything else. Cheers and many thanks!

  3. Hello Mike, my first rebuild on an old Dual 601 and I have repaired, lubed and calibrated everything that wasn’t working. Except for the tonearm return issue. I used the service manual and obtained comparable lubes but could you point out where this rubber cam-end is located please. If you could reference the part number from the service manual, I would be extremely grateful.
    Bill

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