From the values given for R37, it appears that it will cause the rail voltage to go above the rated voltage for the driver IC. This could lead to catastrophic failure of the amplifier. This may be an acceptable risk for competitors but the increase in SPL will be inaudible so I'd recommend leaving the value of R37 as it is.
The diodes shown on the HIP4080 aren't necessary in an amp with the Zeners near the outputs. The ones suggested under the photo on the decibelcar page are the wrong diode and they tell you to install them on the wrong pins. In the photo, the diodes are installed on pins 11/12 and 19/20.
I know this probably isn't what you want to hear but you should repair it with the original part values.
The diodes shown on the HIP4080 aren't necessary in an amp with the Zeners near the outputs. The ones suggested under the photo on the decibelcar page are the wrong diode and they tell you to install them on the wrong pins. In the photo, the diodes are installed on pins 11/12 and 19/20.
I know this probably isn't what you want to hear but you should repair it with the original part values.
Hi perry, I do appreciate your wisdom. So what would you reccommend i change out. i have a contact at RS electronics, So i can get virtually any part needed.
I'm not sure if the photos were your amp.
What components beside the diode and the FET have failed?
What components beside the diode and the FET have failed?
If it were my amp I wouldn't do the mod to increase the rail voltage. These amps are unstable as it is. No reason to make the parts run any closer to their maximum specs.
Thats it is far i can see, caps are fine, resistors are ok, main fuse still o.k
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If the diodes truly make an improvement to the sound quality of the amp then I would be all for that. I don't think the caps would hurt anything but it probably wouldn't make any noticeable improvements either. This is just my opinion though. I am sure Perry or someone else could give you some concrete answers.
If you remove the blown power supply transistor, will the amp power up and produce audio?
Have ALL transistors tightly clamped to the heatsink before applying power. Insert a 15 amp fuse in the B+ line before applying power.
Have ALL transistors tightly clamped to the heatsink before applying power. Insert a 15 amp fuse in the B+ line before applying power.
Its Alive
I dont beleive it, What i did, I changed all my 70n06 fets, tc442 & ic 4080, diode that was split in two identified by you guys. one gate resistor 10 ohm. I have upgraded my 4 big caps to some very HQ ones that a friend sent to me from Germany, added the extra 2 lol😀 Also applied some Arctic silver compound, kept myxbox 360 cpu/gpu cooler, So do not see why it would not do the same for the rail😉 It sounds awesome. I have it all running with a old stiffening cap i had 2.5f, Also Earhquake design, Using streetwires pro series grey/black variety. And PG ti series earh block/fuse. 2 batteries both Optima red tops. its been running now for about an hour.(Running at warm but definatley not hot like it used too, Which feels perfect for me) I think theese new caps have made a huge difference, the bass is much much more defined and detailed. Even though my subs are not designed for tight bass, more for dropping. If i play around with eq Alpine pxa h701/PG bass cube. I can get amzing results in all frequencies!!! Man i wish you guys could here this. I have the biggest grin on my face. The sun is out for once in London & its FRIDAY!! Thanks GuYS. Have a awesome weekend. Get off your pcs. And go and have a beer on me.
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Did you add the diodes on the IC? From the sounds of your results I am considering tearing my earthquake apart again and adding those caps. I have fixed almost all of my previously damaged amplifiers and have been getting bored at night with no repairs to work on.
No did not bother with them i just added some audio grade capsx6 low esr/eww or something. was advised that as i have diodes on or near my fets, I do not need them. i think its all to do with the caps, still smilling Also the Arctic silver compound seems to be disrebuting the heat better. was cosidering fabricating the cover along where the fets sit with a dust cover to get it even cooler, maybe over kill add a couple of micro fans. seems 100% So i go by dont fix unless it is broke, lol
I have an older model that does not have those diodes near the fets so I may give it a shot. Does anyone know if the part number for the diodes listed on that link you posted is the correct part number? I am skeptical because they got the pinout wrong on the 4080. I haven't been able to get any concrete info as to what the part number is on those zeners on the 4080 so far.
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