d8b Forum

Dear All,

I have experienced 2 instances of a loud thump pulsating every second on every input with the monitors bass woofers moving so hard that you can actually see them.

1) I know about the rail-cap problem but if a rail-cap is broken wouldn't the d8b experience this problem every time you switch it on? Today i switched it on and used the desk without any problem.

2) Is the rail-cap problem located on the brain board ONLY?

Thanks

Carlo

I had that once, turned out to be a ribbon connector in the d8b.

I see. I believe that if a rail cap is dead i should experience the symptom every time i boot the desk. Well i will re-seat the ribbon cables and see how it goes.

Dear All,

I have replaced my desk exhibiting the occasional pulsating thump loud noise with my second d8b. Well, it happened on my other desk too. So now i'm certain that the problem is coming from the CPU/PSU unit. Could it be a power problem? What could have gone wrong in the PSU? There is a line PSU pcb with 2 large capacitors. What do you suggest? Are these pcb's interchangeable with something newer? Or shall i change the capacitors and see how it goes. Is it possible that the cables inside the PSU need a clean up with a suitable contact cleaner. Maybe when they expand due to the heat the connection goes off. What do you think please? Anyone had a similar problems with the PSU?

Thanks

Carlo

Carlo wrote:Dear All,

I have replaced my desk exhibiting the occasional pulsating thump loud noise with my second d8b. Well, it happened on my other desk too. So now i'm certain that the problem is coming from the CPU/PSU unit. Could it be a power problem? What could have gone wrong in the PSU? There is a line PSU pcb with 2 large capacitors. What do you suggest? Are these pcb's interchangeable with something newer? Or shall i change the capacitors and see how it goes. Is it possible that the cables inside the PSU need a clean up with a suitable contact cleaner. Maybe when they expand due to the heat the connection goes off. What do you think please? Anyone had a similar problems with the PSU?

Thanks

Carlo

Any help?

Technically, if you´re using powered speakers, it could also be a probem in their power supply.
Have you checked with other speakers or headphones?
(But yeah, given the age, the d8b is the usual suspect).

during the loud noise Thump thump thump (pulsating ) the d8b goes weird so its something Mackie related.