I just replaced Q6 and Q7 in a Brutus Bxi16010d, I used mmbta42lt1g as a replacement I believe it's the exact same part.
I just got it back together to bench test, playing music through it to a 4ohm 'bass shaker' (I don't have a subwoofer to bench test) with the gain set so the amp was pulling 5-10 amps on various bass notes. After about 3 minutes I shut it off to feel various components for temperature.
I noticed the driver board was pretty damn warm at Q6 and Q7, I felt the back side and it was pretty toasty. Not scorching hot, no where near tmax where I'd be worried about failure, but this was only about 2-3 minutes of play time at MAYBE 100watts of power output
Is this normal? I'm going to continue playing, it's my friends amp, he'll be here in a few hours so we can test it in his car. I'm going to be adding a pair of 50 or 60mm fans INSIDE the amp mounted to the bottom blowing in, both on the drive board side, with holes drilled in the opposite end for exhaust. Thta's how I had my brutus 1606 setup years ago, I bought that one new, and ran it over 6 years at 1ohm, pushing it hard daily.
For now the amp wont be pushed hard, until my friend upgrades his subs, I still should be pushing around 600-700w rms out of though for now
I just got it back together to bench test, playing music through it to a 4ohm 'bass shaker' (I don't have a subwoofer to bench test) with the gain set so the amp was pulling 5-10 amps on various bass notes. After about 3 minutes I shut it off to feel various components for temperature.
I noticed the driver board was pretty damn warm at Q6 and Q7, I felt the back side and it was pretty toasty. Not scorching hot, no where near tmax where I'd be worried about failure, but this was only about 2-3 minutes of play time at MAYBE 100watts of power output
Is this normal? I'm going to continue playing, it's my friends amp, he'll be here in a few hours so we can test it in his car. I'm going to be adding a pair of 50 or 60mm fans INSIDE the amp mounted to the bottom blowing in, both on the drive board side, with holes drilled in the opposite end for exhaust. Thta's how I had my brutus 1606 setup years ago, I bought that one new, and ran it over 6 years at 1ohm, pushing it hard daily.
For now the amp wont be pushed hard, until my friend upgrades his subs, I still should be pushing around 600-700w rms out of though for now
Those transistors get extremely hot. So does the op-amp on the top corner of the board.
The components on the board will get too hot to touch, even at idle.
A fan isn't necessary. I've been installing heat spreaders on the driver boards and have never had one come back with any driver board problems.
The components on the board will get too hot to touch, even at idle.
A fan isn't necessary. I've been installing heat spreaders on the driver boards and have never had one come back with any driver board problems.
I know a fan isn't necessary (my old 1606 barely even got warm at 1ohm), I just have excess, and figure why not. lol
Btw Perry I've been following bcae1 for ages, using it info here and there and like wire calculators and stuff. After two of my friends amps took a dive in the last two weeks, I found your amp repair guide! I'm definitely going to be purchasing the full version when I have extra funds available. I've already spent hours reading posts on this forum and learning. Have a few amps laying around I've just started looking into to learn and see if I might be able to repair them without making it worse lol...
Btw Perry I've been following bcae1 for ages, using it info here and there and like wire calculators and stuff. After two of my friends amps took a dive in the last two weeks, I found your amp repair guide! I'm definitely going to be purchasing the full version when I have extra funds available. I've already spent hours reading posts on this forum and learning. Have a few amps laying around I've just started looking into to learn and see if I might be able to repair them without making it worse lol...
EDIT: super long post summed up in bold
Amp was fine after replacing q6 and q7, until one sub failed thermally leading to shorted coils, amp was then tested on bench power supply playing music at low volume just fine, once hooked back up in car, for less than 2minutes with amp turned on, not playing music, ONE filter cap blew, I replaced all 4, played it fine on bench again, not sure what I should test before reinstalling in car
The new transistors worked great for a couple days, with the amp probably at around half its capable output. Until I kicked the gain up a bit, knowing we would likely blow his cheap subs in time.
Didn't expect it to happen in about 30 minutes of constant music on blast. All his output stopped from both his hifonics and his components amp, turns out he never replaced his 70amp fuse with the 150amp fuse yet. He put the 150amp in, the hifonics was in protect. I assumed it was a problem I over looked, I had yet to realize that it was just one of his subs blown and that one sub having a .4ohm load, so I took the amp home, to diagnose, thinking it was just an amp problem.
once I opened it up, and applied limited current, I couldn't find any hot spots. After checking around for a while, I finally hooked up 2 bass shakers for a 2ohm load, and played music for a bit, then called him to have him check his subs, and sure enough he said one was scratchy (he lives an hour away). So I felt the amp was most likely safe, and I continued to let my bass shakers vibrate for over an hour at probably around 100watts. At the end of that, I even put my clamp meter on,and turned the amp up for about 5-10 minutes feeding my bass shakers over 300watts. All was good, I buttoned the amp back up.
When he came back over, we installed it, all wired up right, I even had dmm checking voltage at the amp, solid 14.5v once he put the main fuse in. Fuse was in about 1minute before he turned his head unit on, about 30 seconds later, I a loud buss and cloud of smoke. We hadn't even startedplaying music, and I had the gain all the way down. Pulled the main fuse fast as we could, and I took the amp back out.
Opened it up, and ONE of the 2200uf 80v filter caps blew its top (it was perfect before this).
I don't understand why it blew, just being hjooked up to 14.5v for about 2 minutes. Considering I had just bench tested it, driving a 2ohm load forover an hour at low "volume".
Before I replaced all four of the filter caps, I probed around the amp, no hot spots, voltage looked great, it even drove signal fine into my bass shaker (I barely tuned it up, just enough to feel the shaker have output). No DC on the speaker terminals (well, less than 50mv, with or without load). I replaced all four caps with some spares I had laying around from another amp (same specs, 2200uf, 80v, 105c).
Since then, I've hooked itback up to my bench test, with and without a 2ohm load, drove my bass shakers, even hooked up some full range 6ohm son speakers to it for a bit to make sure the output didn't sound scratchy/distorted. So far no problems.
The regulars don't get hot, the + and - voltage on each side of the power supply are matching and not way off from each other, no DC output on the terminals, the amp pulls NO power with the remote off, pulls about 1.4amps with the amp turned on just idling (I've let it idle for over 30 minutes, and I've also playedinto my bass shakers well over 30 minutes).
The amp when turnedoff and disconnected from the power supply, will hold 12v in the capacitors for long periods of time, I measured the terminals after about 30 minutes and still over 12v (my supply is a motorcycle battery that's currently sitting at around 12.6 with no load on it).
I'm new to this deep diagnosis stuff, so I'm not sure what I should check, before trying to hook it back up in his car. I'm unsure if there is some internal fault, or it was just the luck of the draw that the capacitor decided to blow out of the blue.
Amp was fine after replacing q6 and q7, until one sub failed thermally leading to shorted coils, amp was then tested on bench power supply playing music at low volume just fine, once hooked back up in car, for less than 2minutes with amp turned on, not playing music, ONE filter cap blew, I replaced all 4, played it fine on bench again, not sure what I should test before reinstalling in car
The new transistors worked great for a couple days, with the amp probably at around half its capable output. Until I kicked the gain up a bit, knowing we would likely blow his cheap subs in time.
Didn't expect it to happen in about 30 minutes of constant music on blast. All his output stopped from both his hifonics and his components amp, turns out he never replaced his 70amp fuse with the 150amp fuse yet. He put the 150amp in, the hifonics was in protect. I assumed it was a problem I over looked, I had yet to realize that it was just one of his subs blown and that one sub having a .4ohm load, so I took the amp home, to diagnose, thinking it was just an amp problem.
once I opened it up, and applied limited current, I couldn't find any hot spots. After checking around for a while, I finally hooked up 2 bass shakers for a 2ohm load, and played music for a bit, then called him to have him check his subs, and sure enough he said one was scratchy (he lives an hour away). So I felt the amp was most likely safe, and I continued to let my bass shakers vibrate for over an hour at probably around 100watts. At the end of that, I even put my clamp meter on,and turned the amp up for about 5-10 minutes feeding my bass shakers over 300watts. All was good, I buttoned the amp back up.
When he came back over, we installed it, all wired up right, I even had dmm checking voltage at the amp, solid 14.5v once he put the main fuse in. Fuse was in about 1minute before he turned his head unit on, about 30 seconds later, I a loud buss and cloud of smoke. We hadn't even startedplaying music, and I had the gain all the way down. Pulled the main fuse fast as we could, and I took the amp back out.
Opened it up, and ONE of the 2200uf 80v filter caps blew its top (it was perfect before this).
I don't understand why it blew, just being hjooked up to 14.5v for about 2 minutes. Considering I had just bench tested it, driving a 2ohm load forover an hour at low "volume".
Before I replaced all four of the filter caps, I probed around the amp, no hot spots, voltage looked great, it even drove signal fine into my bass shaker (I barely tuned it up, just enough to feel the shaker have output). No DC on the speaker terminals (well, less than 50mv, with or without load). I replaced all four caps with some spares I had laying around from another amp (same specs, 2200uf, 80v, 105c).
Since then, I've hooked itback up to my bench test, with and without a 2ohm load, drove my bass shakers, even hooked up some full range 6ohm son speakers to it for a bit to make sure the output didn't sound scratchy/distorted. So far no problems.
The regulars don't get hot, the + and - voltage on each side of the power supply are matching and not way off from each other, no DC output on the terminals, the amp pulls NO power with the remote off, pulls about 1.4amps with the amp turned on just idling (I've let it idle for over 30 minutes, and I've also playedinto my bass shakers well over 30 minutes).
The amp when turnedoff and disconnected from the power supply, will hold 12v in the capacitors for long periods of time, I measured the terminals after about 30 minutes and still over 12v (my supply is a motorcycle battery that's currently sitting at around 12.6 with no load on it).
I'm new to this deep diagnosis stuff, so I'm not sure what I should check, before trying to hook it back up in his car. I'm unsure if there is some internal fault, or it was just the luck of the draw that the capacitor decided to blow out of the blue.
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the rails stay the same, right around 58.5v / -58.5v at idle, lowering to around 54.5v on a 4 ohm load prolly pushing 150ish watts to a 4ohm load
I did guess I fibbed the other day when I sad NO dc out on speaker terminals, it was hovering around .140mv the other day, peaking at about .165mv, today I noticed I was closer to .180-,200 at the start, after a fewminute of low volume 80hz sin waves, they were hovering around .300mv DC
My "bench power supply" is running way low atm, using a spare agm motorcycle battery, but i loaned my trickle charger out.. So not the best for testing currently.
Edit: Forgot to hit send on this post last night, but that's good anyways. As I just found out my multimeter hasn't been reading AC right for who knows how long. So I'm going to rest test some things today
I did guess I fibbed the other day when I sad NO dc out on speaker terminals, it was hovering around .140mv the other day, peaking at about .165mv, today I noticed I was closer to .180-,200 at the start, after a fewminute of low volume 80hz sin waves, they were hovering around .300mv DC
My "bench power supply" is running way low atm, using a spare agm motorcycle battery, but i loaned my trickle charger out.. So not the best for testing currently.
Edit: Forgot to hit send on this post last night, but that's good anyways. As I just found out my multimeter hasn't been reading AC right for who knows how long. So I'm going to rest test some things today
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