[Mark-sf]

If it has never been repaired it is overdue to have its electrolytic capacitors replaced. Once this is done and the voltages confirmed your problems would likely be solved. This can be done by a competent technician even without B&O experience.

[Mark-sf]

This could be multiple issues including the servo belt, threaded rod alignment and cleaning/lubrication, loose or cracked pulley, etc. I would attack the mechanicals first before the electronics based upon an issue in only one direction.

[Mark-sf]

Have you performed a re-cap of the electrolytics on the board? The symptom points to it needing that.

[Mark-sf]

You can find the service manual based upon your 5500 Type at beomanuals.com or if you become a Silver member of this site. The procedure is documented there.

[Mark-sf]

I would not suspect the motor in this case based on your symptoms and what you have done to date. You can confirm if you have a 45rpm LP which should make the wow significantly worse if it’s a motor issue. I instead would check the adjustment of the tonearm optical shutter and ensure it is within the i.5 to 2.5 initial rotations and how it behaves toward the end of the record. Since the curve is tighter, if it is not correcting fast enough it can sound like a speed variation.

[Mark-sf]

“Fast” backwards,>>, is the same as Stop so I am still not sure what you are describing. How is the speed compared to moving forward between Play and Stop as well as < and >?

[Mark-sf]

I’m not sure I understand your symptoms. You say going to stop works fine but fast backwards doesn’t. Those functions use the same circuit except for how they are activated. Are you saying that the arm returns fine at the end of record but simply raises and doesn’t when you press Stop?

[Mark-sf]

Great to hear! Keep ’em spinning.

[Mark-sf]

Have you checked/cleaned R160/260 as they control playback output before the meters which I did not realize or had forgotten?

[Mark-sf]

The symptom that’s troubling is that you are observing the problem in both channels but still getting a signal. I would next try Martin‘a suggestion of recording on the 9000 and playing back on another machine. This would help identifying  the defective section.

[Mark-sf]

In your description of work performed you said nothing about the tape heads. Have you cleaned them, checked for wear, and adjusted them?

[Mark-sf]

That type of damage is typically caused by overheating which can be the result of any of the following or in combination:

1. clipping an amp into the speaker
2. if the series capacitor, C2 was too large or shorted
3. if the parallel resistor, R6 is open.

[Mark-sf]

Glitch wrote:

Are B&O and Sound-Smith the only sources of compatible cartridges? I suspect that other sources are unlikely, but wanted to ask to be sure. Thanks, Glitch

Actually, B&O has not been a source for years and are even using a Sound-Smith in the 95th Anniversary Limited Edition 4000c.

On the used market your best bet would be for a non-working table with the cartridge intack as that will likely be cheaper and you can even part out the table to pay for it.

[Mark-sf]

Unless you can find an MMC4 used your best bet is Sound-Smith SMMC4: https://sound-smith.com/cartridges/bo/smmc4 at $200.

[Mark-sf]

I would agree with Martin but initially focus on tracking force if the diamond is still intact based upon your transporting without locking the screws.

[Mark-sf]

Assuming you have tried it with multiple tapes, I would contact the seller as its obviously not in “superb condition”.

[Mark-sf]

Since you are able to play using the < key, the issue is in the << electronic switch. I have found TR12 to be bad though rarely its been TR11. Also I have found TR8 to be bad on the muting board; however, in that case it tries to start and shuts off immediately.

[Mark-sf]

Unfortunately,  there is no industry standard for 12” record weight. They can range from 80-200g. I have never had a problem finding a suspension height that will work with all without bottoming or scrapping. In the end it’s critical that the platter also remain level.

[Mark-sf]

The service manual provides clearance specifics so I would adjust to that with your 180g records.

[Mark-sf]

Check the rear of the tonearm’s clearance with the record edge.

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