Amp Blown? or just my mistake?

 

New member
Username: Halvers0n

Fruitport , Michigan USA

Post Number: 1
Registered: Dec-04
boss r3000d amp
2 power acoustik fubr12
kenwood kdc mp6025

After about 30 mins of tuning and tweaking, the subs were close to peak without bottoming out or distorting...but all the bass ceased.

i checked all fuses (under hood, 3 on amp....) all fuses were fine. amp was still running(internal fan was going and all lights and life signs were positive for the amp), so i took a multimeter and tested the voltage running threw my amp, 13.6 going into it and 0.00 coming out. I did a little digging and found it might be the mosfets in the amp. (Subs are fine tested with another amp).

subs are DVC 2 ohm run (+ to -) (+ to -) (+ to +) (- to -) (- and + to amp)
amp is pushing a 2 ohm load, with 1 ohm stable
 

Silver Member
Username: Chevy_for_life

Post Number: 260
Registered: Sep-04
its a Boss i'd say it might be the amp buddy
 

Silver Member
Username: Oleg

Santa Monica, CA USA

Post Number: 136
Registered: Nov-04
Definitely, my first amp was a boss and I blew it with a 2ohm load in 3days. Better get your money back ASAP and get some legit stuff. The numbers may appear to be less, but believe me, similarly priced JBL, audiobahn, kicker, mtx, orion amps will put out more power, overheat less, and most importantly last a lot longer.
 

New member
Username: Halvers0n

Fruitport , Michigan USA

Post Number: 2
Registered: Dec-04
alrighty well cant get my money back cause this amp has been in service for 2 years. Um what i would really like to know is, when amps blow what is commonly dead? i searched the bread board to see if any char marks or capacitors show markings, nothing, but one of my mosfet chips does not read giving power? could i just replace the chip until i can get the money i need for a real amp

cause i know that PA and boss stuff is not name brand. and not quality. almost got enough cash for 2 RE 15" X.XX and still pickin amp
 

Silver Member
Username: Fryguy

Nova Scotia Canada

Post Number: 402
Registered: Jun-04
Usualy its the output mosfets or the PWM Power Supply section in the amp that burns out, just because they do all the heavy work of pushing the load. If you replace the components you need to buy the MSOFET's in pairs and replace them all. Have you tested the voltage rails from the PWM Power Suply section to be sure you have the positive and negitave rail?
 

New member
Username: Halvers0n

Fruitport , Michigan USA

Post Number: 3
Registered: Dec-04
well your talkin a little over my head, im actually going to college for computer science and my mother is going for her electronics something( dont know exact name) so she is the one testing it for me, and i just tell her what the car audio parts are. do you know of a website that could lay out the schematics of an amp so i could compare? or atleast explain what it would look like?
 

Silver Member
Username: Fryguy

Nova Scotia Canada

Post Number: 415
Registered: Jun-04
That's the problem with electronics now. Everything is considered intellectual property no days so you can't get the schematics for anything unless you're an authorized dealer. Even then you need to sign a (NDA) non-disclosure agreement! So unless you have some electronics experience, it will be difficult to test and fix yourself. Trouble shooting an amp can be a pain in the A$$! (Intermittent problems always piss me @ff fast)

The library can get in some basic electronic books if you want to catch on to the basic fundamentals of electronics and the parts. That's how I learned what I know and use today.
 

New member
Username: Help_2

MN

Post Number: 9
Registered: Dec-04
agreed...
unless theres a burn mark around the bad part...
its quite difficult to determine which piece
has gone bad without the proper equipment/knowledge.
 

Silver Member
Username: Fryguy

Nova Scotia Canada

Post Number: 417
Registered: Jun-04
I'm not discouraging you from trying to fix it. That is after all how you learn.
After all what harm can be done, it is already burned out. The only thing you'll be out is some parts that you thought may have been burned out.

A simple volt/ohm meter will do most of the testing to locate possible problems. A test tone CD will help in testing and calibrating it after it's fixed.
 

New member
Username: Halvers0n

Fruitport , Michigan USA

Post Number: 4
Registered: Dec-04
alright i really appreciate everyones assistance, i think i have it narrowed down to the mosfet chips, (plus i heard mosfet chips blow quicker when higher ohm loads are applied, and my subs are DVC 2ohm, reduced to a 2 ohm load on the 1 ohm stable amp) so ill try the mosfet chips and then prolly scrap it, and buy a real amp. Does anyone know where i can buy the mosfet chips or other parts that go to an amp?
 

Silver Member
Username: Fryguy

Nova Scotia Canada

Post Number: 421
Registered: Jun-04
I see you're in USA so you'll have it easier then me to get from the big guys. I like to use www.digikey.com that's in the US they are fast and a bit more expensive for me in Canada but they have no minimum order and have good packaging unlike some part suppliers.
 

Silver Member
Username: Carguy

Post Number: 835
Registered: Nov-04
Hey Ryan, how old is your mom? If she's going for electronics, that's pretty impressive. Not too many females touch that field. That's as rare as a guy wanting to be a nurse.

 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 6379
Registered: Dec-03
Boss coveres their amps for 5 years I believe.
contact them for warranty repair or replacement.

remember testing output of an amp with a DMM requires using a DMM capable of "True RMS" measurements since the output signal is AC voltage. On a normal, cheaper DMM, AC voltage measures "zero volts" when tested.
 

Silver Member
Username: Carguy

Post Number: 850
Registered: Nov-04
That's a pretty good warranty for a cheap amp.
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 6385
Registered: Dec-03
it's one of their redeeming qualities, really.
at least if ya do blow one up, it's covered for quite a while.
 

New member
Username: Halvers0n

Fruitport , Michigan USA

Post Number: 5
Registered: Dec-04
well sorry i was working for 12 hours but ill answer a few comments:

1) moms 41, yea i know im proud of her
2) I didnt contact Boss, because it says that i had to of bought it from an authorized dealer
3)how do i know if my DMM is just cheap or if a chip is blown?
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 6455
Registered: Dec-03
just look at the directions for the DMM and see if it supports reading AC voltage levels otherwise called "true RMS"

see if it says anything about testing voltage on AC circuits. that'll tell ya.
remember the center point of AC voltage is 0 volts, which is why with some meters you'll only see 0 volts regardless of actual power unless the meter is made to read AC circuits properly.

as for finding the actual FETs for the amp to replace them, if they have an actual part number, try jameco.com
otherwise you need to get the amp schematics from BOSS and part numbers from them.
many companies sand off the part numbers to prevent others from doing repairs or upgrades.
« Previous Thread Next Thread »



Main Forums

Today's Posts

Forum Help

Follow Us