I have a parasound 2205 amp and one channel is dead.I take it a part and the 2 fuses on channel 4 board are blown.
Now all the cap looks fine, the smaller ones and the 2 big 80v 15000uf.
So I replaced the 2 fuses and plug it in and the 2 fuses blew. This is with no pre amp plugged in and no speakers plugged in, just power.
I hate to send it out for repair since it will cost a ton for shipping and I'm not sure of any repair places locally to take it too.
I'm not bad at fixes thing and soldering components on the board.
So any thought if it could be one of the 2 large caps?
thanks for any directions.
Now all the cap looks fine, the smaller ones and the 2 big 80v 15000uf.
So I replaced the 2 fuses and plug it in and the 2 fuses blew. This is with no pre amp plugged in and no speakers plugged in, just power.
I hate to send it out for repair since it will cost a ton for shipping and I'm not sure of any repair places locally to take it too.
I'm not bad at fixes thing and soldering components on the board.
So any thought if it could be one of the 2 large caps?
thanks for any directions.
Well those caps almost often let you see that they are dead, but check the small caramic ones, for black spots, and remove output of your transformer of the board and measure those, or if the transformer is that, the fuse will blow out(sometimes). Do they immediately blow out or after a couple of second, checked rectifier?...
Hi,
Repaired one of these beast earlier this year. The amp is quite heavy... Picked it up for a sound with 2 blown channels. The schematic is available online, so you should start with that. Both bad channels had one shorted output device. It was easy to find the bad part with a ohm meter. Used test meter set to diode test and checked all other transistors. All tested good. You have to wonder what caused the blown output.... I moved on next to the caps. I removed all the smaller caps and checked for Capacitance & ESR. All caps tested good accept for two, with one being really bad(almost shorted). I believe the two were C34 & C37. Too be safe, I replacing all the small caps and made sure I used high temp ones for C34 & C37. One of those caps is located close to a 2 watt resistor. speaking of two watt resistors. The amp PCB has 4 two watt resistors(5.6K), R39, 40, 45 & 46. In my amp ALL of the two watt resistors were way out of tolerance. To repair the Amp I replaced ALL smaller caps(all channels), ALL 5.6k two watt resistors(all channels) and I replaced ALL non polarized caps on the protection PCB. I found bad caps on the protection PCB as well. This is in-addition to replacing the two bad output devices. I did not replace the power supply filter caps. Overall, This was allot of work. If your soldering skills aren't up to the task, don't even go there. Good luck.. Your mileage may vary.
Repaired one of these beast earlier this year. The amp is quite heavy... Picked it up for a sound with 2 blown channels. The schematic is available online, so you should start with that. Both bad channels had one shorted output device. It was easy to find the bad part with a ohm meter. Used test meter set to diode test and checked all other transistors. All tested good. You have to wonder what caused the blown output.... I moved on next to the caps. I removed all the smaller caps and checked for Capacitance & ESR. All caps tested good accept for two, with one being really bad(almost shorted). I believe the two were C34 & C37. Too be safe, I replacing all the small caps and made sure I used high temp ones for C34 & C37. One of those caps is located close to a 2 watt resistor. speaking of two watt resistors. The amp PCB has 4 two watt resistors(5.6K), R39, 40, 45 & 46. In my amp ALL of the two watt resistors were way out of tolerance. To repair the Amp I replaced ALL smaller caps(all channels), ALL 5.6k two watt resistors(all channels) and I replaced ALL non polarized caps on the protection PCB. I found bad caps on the protection PCB as well. This is in-addition to replacing the two bad output devices. I did not replace the power supply filter caps. Overall, This was allot of work. If your soldering skills aren't up to the task, don't even go there. Good luck.. Your mileage may vary.
Hi,
Old thread I know, hopefully someone is still interested on these amps. Found a pretty beat up HCA 2205A for cheap with 1 channel not working. Seems to be a similar scenario as the one described here with both fuses blown. It turns on fine and all 4 channels seem to work fine. Would love to ship it to Parasound for maintenance as John Curl has mentioned here, but I'm located in Ecuador and shipping such a beast back and forth would be incredibly expensive. So I have to work with local technicians, luckily I have a good tech that has helped me with several items from my recording studio over the years.
So in order to try to bring this great amp back to life, I'd like to ask you guys:
-Does anyone have a 2205A schematic?, I've only been able to find a schematic for an HCA1205a which seems to be close but not identical.
-Does anyone have a recommended BOM in order to replace all caps and parts that have become bad over the years? Importing a list of caps & transistors might be more doable than shipping this big guy anywhere and extra few parts than needed might come handy to service it in the coming years.
-Any tips about what could be wrong? I suspect some faulty transistor, all visible caps look fine.
My tech will look into it the next few days and he'll let me know his view of things.
Thanks!
Old thread I know, hopefully someone is still interested on these amps. Found a pretty beat up HCA 2205A for cheap with 1 channel not working. Seems to be a similar scenario as the one described here with both fuses blown. It turns on fine and all 4 channels seem to work fine. Would love to ship it to Parasound for maintenance as John Curl has mentioned here, but I'm located in Ecuador and shipping such a beast back and forth would be incredibly expensive. So I have to work with local technicians, luckily I have a good tech that has helped me with several items from my recording studio over the years.
So in order to try to bring this great amp back to life, I'd like to ask you guys:
-Does anyone have a 2205A schematic?, I've only been able to find a schematic for an HCA1205a which seems to be close but not identical.
-Does anyone have a recommended BOM in order to replace all caps and parts that have become bad over the years? Importing a list of caps & transistors might be more doable than shipping this big guy anywhere and extra few parts than needed might come handy to service it in the coming years.
-Any tips about what could be wrong? I suspect some faulty transistor, all visible caps look fine.
My tech will look into it the next few days and he'll let me know his view of things.
Thanks!
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