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
My beogram plays fine when its not loud,when i play loud the sound dissapers,enywone who knows what rong?
Probably starved for power due to aged capacitors. That wouldn't be a first.Put a scope to the supply rail for the amplifiers and take a look.Which speakers are you using?
Martin
Im for the time using Jamo e410 50w 4ohm
Do you have a picture of what im looking for???
You cannot tell if a capacitor or other component is bad just by looking.You will have to measure and diagnose, - just like most other common electronic repairs.In this case the first point of interest would of course be across the power supply rail.
A bad filter/reservoir capacitor would cause ripple and power surge if the power supply is loaded.A weak voltage regulator circuit would also cause a power drop when loaded, but usually no ripple.A bad rectifier (bridge missing one diode) would produce a 50Hz ripple instead of the normal 100Hz.Easily spotted on the scope.
If all this is fine, I suggest you move on and follow the signal path with the scope to see, where the signal fades, but ifboth channels fail at the same time and under the same conditions, the problem is most likely in a common circuit, which inthe majority of cases means the power supply.
- And it's not because you simply expect too much of this unit?Unless you connect really efficient speakers it won't play loud.It produces less than 2x10 Watts if I remember correctly.Modern speakers are often VERY unefficient, requiring a lot of power just to begin playing at all.
The jamo speakers are from the 70's,and the sound was perfect before,when i turn the volum over half the power the suond dissapears,get weak,goes up and down
Weak power supply.
Hehe my english is very bad,do you mean the transformator???
The transformer cannot be ruled out, but it wouldn't be my first point of focus.As mentioned above, I mean:- rectifier- filter/reservoir capacitor(s)- regulator- any combination of the above
I can't get any closer without diagnosing.As also mentioned, you will have to do some measurements, particularly ripple amount and frequency as these would reveal a lot.To me it sounds like a text-book repair for a trained electronics mechanic.