Dr_Vince Posted August 3, 2020 Share Posted August 3, 2020 (edited) Edit: It seems this is actually C32. I see that value from a previous post. Thanks for all the info; I'll update this post if needed. Hello ngen33r, I have acquired a failed Sub-10 amp and rebuilt the PDC, recapped it, and replaced the FETs. It kept blowing the FETs, though, and measuring the output from the PDC to the FET gate it was 114V, so I figured something must've went wrong with the PDC rebuild. The PDC board was pretty crispy, so I fashioned a new one. Now the power supply seems to be working, the fuse is not blowing, but still no output and no blue LED light. I was testing voltages and suddenly C12 went up in smoke. Do you know what the uF value of C12 is? Edited August 9, 2020 by Dr_Vince Update status Quote Link to comment Share on other sites More sharing options...
Dr_Vince Posted August 14, 2020 Share Posted August 14, 2020 (edited) Thanks again for the great info here. I was finally able to rescue the Sub-10 I bought. The guy before me had trashed the through holes for the FETs and the AC -DC diode bridge. Then I proceeded to trash the through holes for much of the PDC board, since I myself do not have the proper tools either... Anyway, after days of tracking down and repairing damage to the boards, and making a new PDC board, with integrated gate drive resistors, she's up and running with an upgraded Q5 and new Nichicon audio grade caps. Edited August 14, 2020 by Dr_Vince Quote Link to comment Share on other sites More sharing options...
ngen33r Posted August 16, 2020 Author Share Posted August 16, 2020 IMO that is a fire waiting to happen. The VIAS should be replaced and a proper repair done to that board. Credit for getting it working, but I would not want that in my living room. Quote Link to comment Share on other sites More sharing options...
ngen33r Posted August 16, 2020 Author Share Posted August 16, 2020 On 7/30/2020 at 9:15 AM, Miro19 said: MMBZ5243 13V ZENER Quote Link to comment Share on other sites More sharing options...
kyle7k Posted October 8, 2020 Share Posted October 8, 2020 Hello all. I have a Sub 10 does not power on at all. I'd like to get it repaired. I'm generally okay at finding minor issues but this is more than I want to research and sort on my own. Anyone out there up to tackle this for me? Disassembled and ready to ship. Quote Link to comment Share on other sites More sharing options...
Allan B Posted October 31, 2020 Share Posted October 31, 2020 I have a RPW10 that the local repair shop said the sub amp is NFG and needs replacement but they cant find any parts. Is this correct or is it a case of trying to just sell me a new one. Please and thank hyou. Allan Quote Link to comment Share on other sites More sharing options...
Moderators dtel Posted October 31, 2020 Moderators Share Posted October 31, 2020 Welcome Very well could be, unless abused it's usually the amp that goes out. If abused the driver will go out, if you still want it you could get an outboard amp (regular amp) like Crown or any other. Drill a tiny hole for regular speaker wire or remove the plate amp on the sub and run the wire under the edge and your back in business. A stand alone amp is much more reliable than a sub plate amp usually. Disconnect the plate amp but leave it there to fill the space, the sub was designed to have that area filled as to not change the internal size of the cabinet. . 2 Quote Link to comment Share on other sites More sharing options...
ngen33r Posted November 2, 2020 Author Share Posted November 2, 2020 On 10/31/2020 at 5:21 PM, Allan B said: I have a RPW10 that the local repair shop said the sub amp is NFG and needs replacement but they cant find any parts. Is this correct or is it a case of trying to just sell me a new one. Please and thank hyou. Allan These amps are always fixable even if almost destroyed. Quote Link to comment Share on other sites More sharing options...
Kiowa Posted December 10, 2020 Share Posted December 10, 2020 On 7/28/2020 at 9:42 AM, ngen33r said: There is no parts list. TH3 is a DSP104 10ohm 4A inrush limiter. I am also having trouble finding parts and following this thread. I have compiled the fragments of information and I am attempting to build a straight forward list of components that are often abbreviated with "Amp was recapped, replaced TH3, FETs, and Q5" "amp was fully recapped with Nichicon caps" We now have a suggested manufacturer, Can we get a list of the caps and values? "I use GE silicone 2". Good to know, will add that to materials list "I had to clean and rebuild the PDC" Ok, what did that entail? Parts list please? "replace the fets". Can we get a list of PNs? "and TH3". OK, back to the original problem. Where does one find a "TH3"? Do we have a manufacturer and part number? Suggested Parts list with links: 1) Q5 is SOT-23, it needs to be replaced with a TO-92 2N44011 2) TH3 (DSP104) replaced with ???? 3) PDC parts for rebuild. What is all involved in a PDC rebuild? Parts?? 4) FETs replaced with ??? 5) GE Silicone 2 If you can help fill in the blanks I can edit this post and include links for the parts. Quote Link to comment Share on other sites More sharing options...
ngen33r Posted December 19, 2020 Author Share Posted December 19, 2020 2 Quote Link to comment Share on other sites More sharing options...
ngen33r Posted December 19, 2020 Author Share Posted December 19, 2020 On 12/10/2020 at 10:14 AM, Kiowa said: I am also having trouble finding parts and following this thread. I have compiled the fragments of information and I am attempting to build a straight forward list of components that are often abbreviated with "Amp was recapped, replaced TH3, FETs, and Q5" "amp was fully recapped with Nichicon caps" We now have a suggested manufacturer, Can we get a list of the caps and values? "I use GE silicone 2". Good to know, will add that to materials list "I had to clean and rebuild the PDC" Ok, what did that entail? Parts list please? "replace the fets". Can we get a list of PNs? "and TH3". OK, back to the original problem. Where does one find a "TH3"? Do we have a manufacturer and part number? Suggested Parts list with links: 1) Q5 is SOT-23, it needs to be replaced with a TO-92 2N44011 2) TH3 (DSP104) replaced with ???? 3) PDC parts for rebuild. What is all involved in a PDC rebuild? Parts?? 4) FETs replaced with ??? 5) GE Silicone 2 If you can help fill in the blanks I can edit this post and include links for the parts. DO NOT BUY PARTS FROM AMAZON, DON'T DO IT! https://www.digikey.com/en/products/detail/on-semiconductor/2N4401BU/1417 https://www.digikey.com/en/products/detail/epcos-tdk-electronics/B57211P0100M301/2781797 PDC parts are listed on the schematic I made and posted. Rebuild requires replacing what is bad and what PDC you have. There are 2 different versions with different parts. FETS are IRF730/740 depending on the amp you have Everything is available on DigiKey or Mouser, or any reputable parts supplier. Quote Link to comment Share on other sites More sharing options...
dudaindc Posted December 20, 2020 Share Posted December 20, 2020 On 12/19/2020 at 4:21 AM, ngen33r said: AWESOME - THANK YOU! Quote Link to comment Share on other sites More sharing options...
Kiowa Posted December 30, 2020 Share Posted December 30, 2020 (edited) Sub-10: After a full recap, MOSFET, THC, Q5, Z1, and TH3 replacement I went to test the PSU via your video @59:00. I am only seeing 20VDC. I have removed the yellow glue from any visible parts that it could cause a short between. My current limited AC supply bulb is pulsing bright/dim. Also, I see very little voltage between R70 and R71 as you tested @59:43. From this forum I believe you are saying the issue is the BASH board or PDC. What would cause the +15V_M and -15V_M at (U4 Pin3 & U5 Pin3) to be limited to 20VDC instead of 25-30VDC and is this acceptable? I removed the PDC and BASH boards and I no longer see a pulsing bulb on my AC limited supply. How do I troubleshoot these two boards to determine where the fault is? The DB1 BASH3010A IC on the BASH board. If that is faulty, where can I find a replacement chip? I plan to put a single row female socket 8P and 12P header on the board so that I can more easily remove the PDC and BASH sub-boards for troubleshooting until I can figure out where the problem exists. Edited December 31, 2020 by Kiowa added images Quote Link to comment Share on other sites More sharing options...
Kiowa Posted January 10, 2021 Share Posted January 10, 2021 (edited) With the PDC removed I get 150V out of the D6 rectifier so that portion of the PSU is working now that the inrush limiter has been replaced. I did a full rebuild of the PDC with the schematic and parts listed in this thread. When I measure across the body of U4 and U5 according to your video I should see ~30V. I am only seeing 2.5 volts (with a lot of wild variation on the meter) and my AC limited supply bulb is pulsing bring/dim. Do you have any suggestions on how to better validate operation or troubleshoot the PDC board? here is a quick video: Video Update (even thought it looks like this thread is pretty much dead): The problem was having the BASH board removed during testing let the Gate Drive that feeds Q7 float and damaged Q7. I also noticed Q14 was shorted as well (Both had been replaced during my rebuild once already). Removing both Q7 and Q14 (both IRF530). Then replacing Q7, puts the amp in working condition from a power supply perspective. No more pulsing AC bulb. I see ~22VDC across the body of U4 and U5. I see the 5VDC across R70 and R71. Everything looks good. I verified the BASH board is getting 15VDC as well. Problem: The problem is when I populate Q14 (IRF530) the flashing AC limiter bulb is back and the board is unhappy again. Not sure what to troubleshoot on the Q14 side. The PDC and BASH seem to be working to me. Would this be an indicator of a bad U3 opamp? Thanks Edited January 10, 2021 by Kiowa Quote Link to comment Share on other sites More sharing options...
ngen33r Posted January 11, 2021 Author Share Posted January 11, 2021 On 1/9/2021 at 8:00 PM, Kiowa said: With the PDC removed I get 150V out of the D6 rectifier so that portion of the PSU is working now that the inrush limiter has been replaced. I did a full rebuild of the PDC with the schematic and parts listed in this thread. When I measure across the body of U4 and U5 according to your video I should see ~30V. I am only seeing 2.5 volts (with a lot of wild variation on the meter) and my AC limited supply bulb is pulsing bring/dim. Do you have any suggestions on how to better validate operation or troubleshoot the PDC board? here is a quick video: Video Update (even thought it looks like this thread is pretty much dead): The problem was having the BASH board removed during testing let the Gate Drive that feeds Q7 float and damaged Q7. I also noticed Q14 was shorted as well (Both had been replaced during my rebuild once already). Removing both Q7 and Q14 (both IRF530). Then replacing Q7, puts the amp in working condition from a power supply perspective. No more pulsing AC bulb. I see ~22VDC across the body of U4 and U5. I see the 5VDC across R70 and R71. Everything looks good. I verified the BASH board is getting 15VDC as well. Problem: The problem is when I populate Q14 (IRF530) the flashing AC limiter bulb is back and the board is unhappy again. Not sure what to troubleshoot on the Q14 side. The PDC and BASH seem to be working to me. Would this be an indicator of a bad U3 opamp? Thanks The BIAS could be way off or the volume is too high. Testing should always happen with the volume at 5% or less. If the outputs were replaced the pots will need to be adjusted. I plan to cover this in a future video. The unmarked DIAC is a DB6 and can be sourced from NTE. 1 Quote Link to comment Share on other sites More sharing options...
Kiowa Posted January 11, 2021 Share Posted January 11, 2021 (edited) 19 hours ago, ngen33r said: The BIAS could be way off or the volume is too high. Testing should always happen with the volume at 5% or less. If the outputs were replaced the pots will need to be adjusted. I plan to cover this in a future video. The unmarked DIAC is a DB6 and can be sourced from NTE. I found the issue. When I replaced the MOSFETs I attempted to read the part numbers off of the parts removed and replace with the same parts. I got the Q13 and Q19 wrong. Instead I replaced with the following and all is working now: Q14,Q20,Q7=IRF530 and Q13,Q19=IRF9Z14 or IRF9530. Like to see the pot tuning video. I don't have an expensive set of 8ohm resistors to sink the amp into. Can you cover tuning with conventional setup just using the speaker connected? Edited January 11, 2021 by Kiowa Quote Link to comment Share on other sites More sharing options...
Eric Vigil Posted January 12, 2021 Share Posted January 12, 2021 Hi ngen33r, I have a sub12 with a dead amp that I'd love to just buy a replacement for. Would you happen to sell refurbished amps? -or- would you happen to have a source for this? I'm confident enough to unhook and replace the amp but not much more than that. Thank you, vigileric@hotmail.com Eric Vigil Quote Link to comment Share on other sites More sharing options...
Travs69 Posted January 12, 2021 Share Posted January 12, 2021 Same here.. I can do basic soldering but this is beyond me. Id be happy to send my amp out and have someone else repair it. Quote Link to comment Share on other sites More sharing options...
Jmoore4717 Posted January 19, 2021 Share Posted January 19, 2021 Where are you finding this DB6 Diac? Ive looked on NTE's website and a search brings up nothing. I found a NTE6416 that looks like it might work as a substitute but not 100%. Do you know if that will work as a replacement? Quote Link to comment Share on other sites More sharing options...
Foxrunner2099 Posted January 20, 2021 Share Posted January 20, 2021 ngen33r just curious how much do you charge for repairs? i have a synergy 12 that powers on but the unit just hums. Quote Link to comment Share on other sites More sharing options...
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