Diagnosis of noise

Hi-Fi Corner
1

Hello , I have a 250.2 power amp that I’ve owned for years , When I switch on the amp creates a low level buzz through both speakers for about 7 seconds then just disappears.Its always done this .
Any ideas what this might be . For clarity another 250.2 I have does not do this .
When used in an active set up if on treble it’s audible for the 7 secs , mid less so and if on bass duty you would not even know it does it .
Anyone experienced this. It has never got worse over years and there are no visible problems within the amp .

Thanks

2

I will have a stab in the dark. Main power supply filter capacitors. It is a little difficult without a CRO.

Does anybody else have any ideas?

Warm regards,

Mitch in Oz.

3

Has it been serviced?

4

It’s a common thing. Absolutely nothing to worry about.

5

Never serviced ,I know that will be recommendation . But it’s always done it and sounds identical to another one I have of same age . It’s ten years old now and has done it since 6 years old when I first even noticed . In days of old I left the amps on 24/7 , but last couple of years only on for use .

6

Have a read of this thread @Keltik

7

Thanks for link ,sounds like same issue although mine only suffers for seconds ,and has not got any worse over the years . Just a pain if selling on I suppose.

1 Like
8

Are you using a Naim pre amp.

9

This 250.2 has been fronted by Snaxo , 82s and 52s always same effect ,a 5 to 7 seconds buzz from speakers on switch on then silent .
Yes kit is always switched on in correct order.

1 Like
10

Just leave the system powered on, it’s not going to wear out sooner.

1 Like
11

Just sounds like caps charging. :thinking:

1 Like
12

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.