Kustom X MPA Monural Power Amp [message #26715] |
Wed, 23 May 2018 13:29 ![Go to next message Go to next message](/FUDforum/theme/vk30/images/down.png) |
jammy5152
Messages: 61 Registered: May 2018 Location: Georgia
|
Member |
![jtweedell%40att.net](/FUDforum/theme/vk30/images/yahoo.png)
|
|
I just recenlty got a Kustom X Monural Power Amp 130 rms @ 8 ohm and when I got it hooked up through a mixer and microphone, it started good but after a while it started with a soft hiss and then gradually got louder until the hiss was LOUD and unbearable so I just turned it off...
Using freeze spray to try to isolate it did not do much good in locating a bad component...
Would like someone to given me ideas in repaing it
It uses a 5065 board which I was told
Thanks
[Updated on: Wed, 23 May 2018 13:30] Report message to a moderator
|
|
|
Re: Kustom X MPA Monural Power Amp [message #26716 is a reply to message #26715] |
Wed, 23 May 2018 23:53 ![Go to previous message Go to previous message](/FUDforum/theme/vk30/images/up.png) ![Go to next message Go to next message](/FUDforum/theme/vk30/images/down.png) |
chicagobill
Messages: 2005 Registered: April 2003
|
Senior Member |
|
|
Welcome to the place!
I thought that the X was a stereo power amp, but I could be wrong. Is the hiss changed by the volume control? Is the hiss there when there is nothing plugged into the input? Does the hiss go away after the amp has been turned off for a while and then slowly build up again?
Hiss could be caused by many things, most often active devices like transistors, but also from old carbon comp resistors. Later versions of that power amplifier design used a number of 1% metal film resistors to help keep the noise down.
What sort of electronics skills do you have and what sorts of test equipment are available?
Again, welcome to the place.
|
|
|
|
|
|
|
Re: Kustom X MPA Monural Power Amp [message #26721 is a reply to message #26715] |
Fri, 25 May 2018 05:57 ![Go to previous message Go to previous message](/FUDforum/theme/vk30/images/up.png) |
stevem
Messages: 4759 Registered: June 2004 Location: NY
|
Senior Member |
|
|
There must be a preamp board in there besides the 5065 driver power amp board because that 5065 board takes way takes way more then + 4 db out of a mixer to drive the output stage to 130 watts!
Is there another board?
If it is a issue on the 5065 board then I would say that transistors Q1 and Q2 are most likely suspects!
[Updated on: Fri, 25 May 2018 06:04] Report message to a moderator
|
|
|