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Dual 601 Belt-Drive Turntable Service

I’ve just had a classic Dual 601 belt-drive turntable in for a major service and it’s almost as good as new!

This particular Dual 601 needed recommissioning after an extended period of more than ten years in storage. The automatic tonearm functions were not working correctly and the deck needed a comprehensive grease and lube, plus proper tonearm setup.

So, for this Dual 601 service, I added synthetic oil to the dry main bearing assembly and carefully greased and lubed the key parts of the automated start and stop assembly, plus arm movement actuator. The automated tonearm movements were still not working though and this required further diagnosis.

This symptom is very common on the Dual 601, and other Dual turntables featuring an automatic arm return mechanism. I serviced another Dual 601 and discussed the problem here.

The problem turned out to be a small rubber part that had decayed and fallen off its original point of installation. Without this part, the tonearm can not be ‘gripped’ by the return mechanism and therefore won’t move. I fashioned a replacement part and now the arm works exactly as it should. I have since used this repair methodology in several other Dual turntable repairs.

The owner was very pleased with the result of this major overhaul of his Dual 601. What follows is a few images outlining some of the steps involved.

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German, elegant and well-made, these are complex decks. The automatic mechanisms need extensive service at this age and many different and quite specific types of lubricant.
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At first, it’s hard to figure out what is going on. Many points to lubricate here…
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Trouble typically occurs here, often causing the tonearm not to return properly, or at all. In this case, a small rubber nipple that causes the arm to return had dissolved into nothing over time. This is a frequent source of trouble with Dual turntables.
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This master control cam needs to be carefully checked, cleaned of old grease and lubricated. I use a special synthetic grease of similar viscosity.

 

Thanks for reading and don’t hesitate to get in touch if you’d like your Dual 601 serviced and repaired.

Liquid Mike

As a kid, I cherished my Tandy 200-in-1 electronics project lab, Dick Smith electronics kits, my Dad's hi-fi and my own first proper system. Later, I created Liquid Audio to help keep classic hi-fi gear alive and well. Our mission: to deliver TLC for classic Japanese, American and European hi-fi stereo equipment.

This Post Has 5 Comments

  1. Gary

    Hi mate , do you know we’re I can get a counter balance weight for a dual 521
    Regards Gary.

  2. Ben

    I’ve just purchased a Dual 601, lovely equipment but does have a loud hum, like an earthing problem .

    1. Liquid Mike

      Hi Ben, thanks for commenting, hum problems have many causes so tracing the source is important. Cartridge issues, wiring problems in either the arm, connectors or lead-out cable, bad ground connections, ground loops between pre and power amp and so on. As I always suggest, if you are local, you could visit with the deck and I can do some troubleshooting for you. If you are not local, it becomes harder for me to help from a distance, unfortunately.

  3. Rich O

    Mike, do you have any other pictures or descriptions of the auto-return repair? Could this worn part also cause the initial grab and drop of the tone arm to malfunction as well?

    1. Liquid Mike

      Hi Rich, only what you see in the article at this stage. There are many more photos, articles to be written and never enough time to put them together unfortunately!

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