My dad has been a home theater fanatic since the 90’s when the first affordable Dolby Surround kits started to hit the stores. His first one was a ready-in-a-box set but it didn’t take long for him to start building his own vision by replacing the speakers, amp and subwoofer by better quality ones. Because this was a hobby, all the parts were chosen by their success in hi-fi magazines regardless of the price. Since then the technology has come a long way and newer models are more refined and better equipped while the prices have come down but they are still more expensive than ones saved from a trash pile. On top of that the ones bought from a store don’t give me that feeling of accomplishment that the recycled ones do once I get them to work. At this point it might be fair to mention that many of the devices on this blog have given out sooner or later in a way that fixing them wouldn’t be feasible or cost-effective any more.
Having served faithfully for more than a decade, the 5.1 channel amplifier had started to make weird clicking noise and my dad was afraid that it could be a fire hazard. He had already thrown the amplifier on top of a pile of junk headed for the junkyard when I intervened and rescued it. I decided to take the amp home for closer inspection because it had line level RCA-outputs that my own amplifier lacked. I had been using a converter to attach active speakers to speaker outputs and the sound quality was horrendous. Because I assumed the clicking noise was caused by some relays’ old age and dust and dirt accumulated on some contacts, I figured that there was no immediate danger in using the amp. I plugged the newly acquired amp into my existing set-up and just started using it. Because of the line level outputs the sound quality improved dramatically. It took me several months to grow tired of clicking relays.
Finally I detached all the cabels of the amp and opened it up to locate the faulty relays. They were easy to find, so I started figuring out how get my hands on them from the opposite side of the PCB. To my surprise I realised that Sony had taken the serviceability into account in the design process. On the bottom of the amplifier there was removable hatch that allowed me to inspect the solder joints. A quick glance was enough to find the cause for the clicking. One of the solders on a relay was cracked and that caused it to open circuit seemingly randomly. The fix was fairly easy. I just removed the old solder and re-soldered it. After this the clicking ceased and I was happy for a while.
I would have been happy longer if I had just stuck with my 3.1 arrangement. I wanted to experience the full surround sound immersion so I added rear speakers to the set-up. Since I didn’t want speaker cabels running across the living room floor, I decided to route them via the ceiling. With my girlfriends’ help I installed cabel trays and hid the cabels there. After two days of hard work the trays were installed and the rear speakers plugged in. First thing I noticed when testing the new set-up was that the clicking had returned. This mighty have caused my blood pressure to rise slightly but luckily the fix to this was the same as for the front speakers. When first fixing the relays I didn’t realise that there were dedicated relays for front, rear and center speakers as well as for the subwoofer. I re-soldered all the relays I could find because those that weren’t cracked yet would crack eventually so I went over all the solders that I could find. The amp has been working flawlessly for well over a year now and I’m happy with it considering the cost and everything.
