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Beolover SyncDrive: DC Platter Motor Replacement for Beogram 4002 and 4004 (Type 551x and 552x)

Late Beogram 4002 and the 4004 (Types 551x and 552x), which have DC platter motors instead of the earlier synchronous AC motors usually suff...

Monday, May 27, 2024

Another Surprise Addition To The Workshop Beogram 4004

 Back in 2021 I restored my own personal Beogram 4004 turntable, dubbed the "Workshop Beogram 4004".  That same year I added the Beolover Remote Commander to it and have happily been playing a lot of records with it.

This year I have another surprise addition to my Beogram 4004...a Beolover SyncDrive Platter Motor.

Ever since reading the Beolover Blog announcing the Sync Drive I have been wanting to try it out.

As I mentioned, my Beogram 4004 was already restored and I use it regularly.
The DC platter motor had been restored by Beolover back in 2021 and works great.

However, I love the idea of a self calibrating platter motor that is even more accurate and was ready to try it out in person.

First, I remeasured the original DC platter motor using the Belovover RPM Tool v2.
I wanted to have current values to compare the original platter motor with the SyncDrive.

This screenshot shows the measurements from the Beolover RPM Tool v2 being recorded on a PC.

I ran the measurements for twenty hours.  Of course that is way longer than a platter motor would ever be run in normal use but it has been the length of time we usually collect RPM measurements on the Beolover Blog for comparison.

After saving off the measurement data for the original platter motor (at 33.33 RPM) I switched out the motor with the new Belover SyncDrive.

The changing of the motor is incredibly easy.

Here is the Beolover SyncDrive as received from Beolover.

Here is the connection point to the Beogram 4004 main board.

Here is the SyncDrive installed.

...and turned on by starting the platter turning and pressing one of the SyncDrive control buttons.

The SyncDrive came on showing me that my current settings have a 33.33 RPM value that is a little too fast.  Not surprising since I hadn't run a calibration with the SyncDrive yet.

Here is the Beogram 4004 platter speed measurement with the SyncDrive installed and after it calibrated itself for 33.33 RPM.

How great is that?  So easy.

My favorite features of the SyncDrive are its control buttons.
I love being able to run automatic, self calibration for 33.33 and 45 RPM.
I also really like locking out the original Beogram control panel speed adjustment controls.

Now for the measurement comparison.
Using the Beolover RPM Tool v2, I also measured the 33.33 RPM of the Beogram 4004 platter using SyncDrive.  Again, I ran the measurement for twenty hours.

Looking at the measurement results you can see that both platter motors produce a consistent and controlled platter speed for twenty straight hours.

That is what I expected.  After all, my original DC platter motor was restored by Beolover back in 2021 and should easily last another forty years.

However, you can also see how much tighter the RPM measurement is with the SyncDrive controlling the speed.

Also note that the mean for the original platter motor shows that it had drifted a bit slower than my original setting in 2021.  It measured a mean value of 33.24 RPM.  
The 33 RPM trimmer on the Beogram 4004 main board could be used to readjust that along with a good measurement tool like the Beolover RPM Tool v2.

With the SyncDrive motor that type of readjustment is no longer necessary.  You simply press the Auto Cal. button and two minutes later the platter speed is calibrated and locked in.

With either a Beolover restored DC platter motor or a Beolover SyncDrive, a Beogram 4002/4004 owner can get a beautifully functioning turntable.  I just prefer (and appreciate) the technical achievement and performance of the SyncDrive.

Now back to listening to records.

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