IPB

Welcome Guest ( Log In | Register )

Need help on identifying amp defect
soulsearchingsun
post Mar 1 2012, 14:26
Post #1





Group: Members
Posts: 145
Joined: 27-January 05
Member No.: 19370



I'm having issues with my mid-90s Sony solid state amp.
In particular the right channel is of lower volume (~-12dB in my measurements) and the sound is distorted in a way that there is noise added when I feed a signal to the amp. On silent parts, there is no additional noise. I ruled out the signal source and the speakers as the cause, it has to be the amp. I looked inside to see if I can find burned components, but I haven't had luck yet. I can't see the whole circuit board without disassembly (which I haven't done yet) though.

I uploaded a file here, with the following setup:
sound card output -> amp line level input; amp speaker out -> sound card line level input & speakers

Could anyone give me hints where I should look for the defect? Is this typical for some specific defect?
Thanks a lot!

edit:link now pointing to upload thread

This post has been edited by soulsearchingsun: Mar 1 2012, 14:32
Go to the top of the page
+Quote Post
 
Start new topic
Replies
pdq
post Mar 1 2012, 16:08
Post #2





Group: Members
Posts: 3305
Joined: 1-September 05
From: SE Pennsylvania
Member No.: 24233



We could probably look for some characteristic distortion resulting from a common failure mode (without even looking/listening I am betting blow drive transistor), but is it really worth it? The likelihood of it being something simple/inexpensive to fix is small, and the cost of an excellent replacement is quite modest, so I think you should just bite the bullet, so to speak.
Go to the top of the page
+Quote Post
soulsearchingsun
post Mar 1 2012, 17:45
Post #3





Group: Members
Posts: 145
Joined: 27-January 05
Member No.: 19370



QUOTE (pdq @ Mar 1 2012, 16:08) *
I am betting blow drive transistor
I'm not too proficient with the technical terms, although I have some basic knowledge about how amplifiers work. Are you talking about the output transistors or something before that stage?

QUOTE (pdq @ Mar 1 2012, 16:08) *
but is it really worth it? The likelihood of it being something simple/inexpensive to fix is small, and the cost of an excellent replacement is quite modest, so I think you should just bite the bullet, so to speak.
I'm on a very low budget and refuse to throw things away that could be repaired with modest effort. A replacement amp with remote will cost about 40-50 (~50-65USD) w/ shipping, I won't have a guarantee that my replacement unit doesn't die for the same/different reasons shortly after buying. I know there's a sweet spot between the effort of fixing something and buying a replacement, but I can't see how I possibly could hit this with buying some components. Thanks nevertheless for your advice, I'll at least keep my eyes open.
Go to the top of the page
+Quote Post

Posts in this topic


Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



RSS Lo-Fi Version Time is now: 21st April 2014 - 15:49