Earthquake PHD2 seems to lower output???

[Perry Babin]

Is the power supply producing rail voltage?

 

[caribboy]

Yeah Perry, im getting 94VDC at the rails, power light is on. Im using four FETs in the power supply at this time as im just testing the Amp to see if its stable, When im finished ill put all the Fets in. im using Four IRFZ44N two on each side for power fet.... And four RFP40N10 for output two on each side...im not getting any Audio output when a signal is passed through the Amp. any solutions?

Thanks..

 

[Perry Babin]

What's the DC voltage feeding the amp. 94 v is too much for the IC.

 

[caribboy]

im using a Computers power supply, 12V Dc powering the Amp! Any reason im getting so much volts at the rail?

 

[Perry Babin]

Measure the DC voltage directly across the power/ground terminals of the amp.

 

[ppia600]

Yeah 94v is way too high, the oem caps are 80v I believe. Could the amp have been modded for higher voltage? What values are the power supply large caps?

 

[caribboy]

The power Supply large Caps are rated 100V 470uF....i think their is a mod for the Amp which allows more volts to the Rail therefore more Power...
1.Replace R08 with 10ohm
2.Replace R37 with 75kohm
This will increase rail voltage for more power output.

And i got the Amp with these Mods in place....The problem is getting the Preamp of the amplifier to start fireing as it Should...

So where do i go from here....???

 

[Perry Babin]

Do you have an oscilloscope?

 

[caribboy]

I dont have an oscilloscope...I am thinking of getting one of those Fluke with oscilloscope..way out of my budjet right now..

If you tell me what to check for i can get a friends scope to borrow??

Thanks!!!

 

[Perry Babin]

While a Fluke Scopemeter is an excellent piece of equipment, it's a VERY poor choice for audio work. An inexpensive analog scope with a conventional (CRT) display is generally going to be a much better option.

Post a photo of the signal on pin 6 of the HIP4080. Set the scope to 5uS, 2v/div and set the coupling to DC.

If you don't have a test tone CD or a signal generator, burn the following file to an audio CD and drive a 1v signal into the amplifier. Measure the AC voltage at the RCA jacks on the amp and confirm that you have 1v AC. Set the crossover to the highest frequency and set the gain to the maximum setting. Post a photo of the waveform on pin 7 of the 4080.

http://www.bcae1.com/temp/100hz300seconds.zip

 

[caribboy]

Will do and post the pictures.....

Caribboy!!!

 

[caribboy]

Hey Guys i ran into some problems....While testing voltage at the output on the amp i accedentally shorted the probe and burnt the HIP4080😡😡😡...Going to source a new one and continue testing!!!!..

Back to Square one!!!!!!

 

[caribboy]

The Amp is actually the 200DHC-MARK 2A ....The older Versions to the PHD2..

Thanks guys for the assistance im now awaiting the HIP4080 chip..
About two days time...

Regards!

 

[Hectorscaraudio]

Perry I have one of these amps too that Iam fixing up. Before I order the parts for the DB 1200 , I would like to fix this one too. What would be a good sub for the output mosfets RFP40N10 , Thank you.

 

[Perry Babin]

IRF3710Z (<<< Z is VERY important).

I won't answer any other questions here. Start a new thread if you need help.

 

[ppia600]

Bumping this back from the dead, because I snagged a NIB ph5000w a while back, and while it's obviously not capable of anywhere near "5000w" :lol: ...it should make a little more than the PHD2 I owned previously. Hopefully I don't make any installation flaws and the upgraded alternator keeps the voltage high enough to keep the amp satisfied.

Definitely won't be messing around and playing with a 6" woofer in the rear deck, like the previous amp!

Figured I'd pop back in and see what people are destroying and repairing nowadays.