Hey guys,
anyone with experience repairing crown xti 2000 amplifier?
Need some help.
amp power button is tuned on all leds light up but it just stays at that point, the display does not come on and the relays stay off.
anyone with experience repairing crown xti 2000 amplifier?
Need some help.
amp power button is tuned on all leds light up but it just stays at that point, the display does not come on and the relays stay off.
I have recently picked up a 'not working' XTi 2000, it wouldn't switch on, so I found the power supply low side IGBT had blown and the LO/HI side driver chip, I replaced those and the amp worked at first on the bench (first through a 150 watt light bulb in series with the mains to limit current), then worked direct mains connected.
I took it home and it switched on fine, switched off, then on... nothing.
Replaced the same parts and the same events happened again... twice..
I have looked at the PWM psup design and decided it is not a good design, there is no dead-band time, no PWM regulation, only the supply to the PWM chip is cut to regulate the output voltage, no soft start.
Since I have replaced the chips so many times, I am going to retro-build my own PWM controller, using the same TL494 PWM controller, using a 2 amp output hi/lo IGBT driver, and removing the onboard PWM, IGBT driver, and transistor gate current driver follower. The PWM controller will use a constant 15 volt regulated supply and use the existing supply comparators to control the PWM, and install soft start and UV shutdown.
I took it home and it switched on fine, switched off, then on... nothing.
Replaced the same parts and the same events happened again... twice..
I have looked at the PWM psup design and decided it is not a good design, there is no dead-band time, no PWM regulation, only the supply to the PWM chip is cut to regulate the output voltage, no soft start.
Since I have replaced the chips so many times, I am going to retro-build my own PWM controller, using the same TL494 PWM controller, using a 2 amp output hi/lo IGBT driver, and removing the onboard PWM, IGBT driver, and transistor gate current driver follower. The PWM controller will use a constant 15 volt regulated supply and use the existing supply comparators to control the PWM, and install soft start and UV shutdown.
Did you replace C68, that capacitor failing will kill one or the other output fets. Did you find the cause or just replaced the damaged fets, leaving it to fail again.
The designers at one of the most professional amplifier manufacturers would doubtless not produce a power supply that is unstable. Components can and do however fail.
Most issues with these amplifiers is directly caused by the connections between the front panel and the amplifier board.
The designers at one of the most professional amplifier manufacturers would doubtless not produce a power supply that is unstable. Components can and do however fail.
Most issues with these amplifiers is directly caused by the connections between the front panel and the amplifier board.
Not replaced C68, I only checked it was not shorted, good call though.
Front panel seems OK, after I replaced a blown LCD backlight led.
While the amp works for a short period, and a speaker is plugged in, there is a noticeable speaker 'pop' when switched on and off in both channels, I hope this is normal with this model amp.
Front panel seems OK, after I replaced a blown LCD backlight led.
While the amp works for a short period, and a speaker is plugged in, there is a noticeable speaker 'pop' when switched on and off in both channels, I hope this is normal with this model amp.
Hi Gumtown, would you mind elaborating on the LCD backlight led replacement? I have one that has no backlight. You can still read the display in the right lighting.
Thanks,
Tim
Cant the issue with display ampboard be ignorera if one resets the amp and make new settings through computer with the crown dsp program? I was/am hoping this could solve that issue since I would like to use a xti2000 that has a broken display and one Channel is now putting out a lower signal to one channel. I’ll use in bridge mono for sub duty so maybe this is a non issue n my case?