ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi to all...
It's been a long time since I acquired a cap kit from Dillen for my Beomaster 8000, which I unfortunately never put in place. Since my machine was playing perfectly, and displayed no problem whatsoever, I didn't want to do more harm than good...
Then, a few weeks ago, some distortion appeared from the left output (it's coming from the amp, not the speakers, and from every line inputs, already checked these possibilities): It is absolutely unnoticeable when listening to pop/rock music, but it's really obvious when listening to classical piano music. When I cranked up the volume a few seconds and put it back to normal, the distortion disappears. Now that trick doesn't seem to work anymore, but I noticed that the problem becomes less obvious after a few hours of operation.
Since I managed to successfully changed about 65 components on a Beomaster 2400, maybe it's time to go inside this one... But i'm so afraid of disturbing something I shouldn't:
-For the left output, Do you completely remove the second operating panel with the pcb under it when servicing the output stage or you just lift up both components?
-When removing the socket panel, does it unplug easily from the preamp?
-When adjusting the new trimmers, do you crank them completely counterclockwise before putting the machine on and making the adjustments to 18mv or you can leave them to their default setting, right before the adjustment, without being afraid that something might explode? Also, does the socket panel can stay unplugged before doing the adjustments?
...I would also like to have your opinion on this one: My beolab 8000 system is plugged on a power bar. After using it, I put everything on standby, wait for about a minute, and then I turn off the powerbar. Is it a good thing to remove any tension from the set or not? Or is it useless?
Thank you very much for your time and help! Any other advices concerning my project are welcomed and really appreciated!
Operate the speaker switches a couple of times.
Martin
Thanks Martin,
Already done that, does not change anything. Seems to be a distortion related to a particular frequency. Like when an object comes in resonance and vibrates. Only it comes from the speaker. I swapped them to confirm that the source was really the amp. I also tried the 2nd left output, same problem.
Guillaume
Could be a crossover distortion.Replace the capacitors and trimmers in the amplifier sections and readjust.