Pioneer Spec 2 Repair And Restoration

This Pioneer Spec 2 is forty years old and is in need of some service.

I have now removed the bottom cover of this Pioneer Spec 2 power amplifier.

Look at the discoloration on those pins......A pencil eraser will clean them up.  

After cleaning the connector pins on this Pioneer Spec 2 the pins are looking much better.

Some of these transistors just heat themselves to death and should be replaced. 

I removed the top cover of this Pioneer Spec 2 solid state power amplifier. The Spec 2 has a nice and neat chassis layout.

I have loosened the meter assembly so that I access both sides of the assembly for capacitor and transistor replacement. 

I removed the pre/power amplifier assembly so that I will have access to the assembly for transistor and capacitor replacement.

Sometimes even a hockey puck can help out as a third hand when repairing or restoring vintage audio equipment.

I have removed the faceplate of this Pioneer Spec 2 to clean it as well as the decades of dirt that has collected behind the faceplate.

I will be replacing the four filter capacitors during this Pioneer Spec 2 repair and restoration.

The four original Nippon Chemi-Con filter capacitors are 15000uf and rated at 100 volts.

The new filter capacitors that I will be using are Nippon Chemi-Con 22000uf and rated at 100 volts.

 Nippon Chemi-Con is a Japanese company but these capacitors are manufactured in the USA which is noteworthy as most are now made in China.

The original filter capacitors used in this Pioneer Spec 2 used wire wrap terminals. This was the normal method for connections in the 1970's.

The modern replacement capacitors use screw type terminals. I will use ring terminals to make the connections to the new capacitors.

Before removing any wires just take a minute and take pictures or draw out the wiring on paper. This may help you if you run into trouble.

I have started to remove the wiring from the filter capacitors during this Pioneer Spec 2 repair and restoration.

I have started to solder the ring connectors to the wiring for the new filter capacitors screw type terminals.

I have two of the new capacitors installed and now I'll get the other two changed out.

With the filter capacitors out of the way this is a good time to change out any components needed on the power supply circuit assembly, AWR-093.

I have mounted the last two filter capacitors in the Pioneer Spec 2 power amplifier and they are ready to be hooked up.

The last of the new filter capacitors are installed. This Pioneer Spec 2 amplifier is getting ready to start it's next 40 years!

It's always a good idea before reassembling to test out your work. This Pioneer Spec 2 powered up fine.

33 transistors and capacitors were replaced during this Pioneer Spec 2 repair and restoration.

Always use respected names for your replacement components. Just pennies more for the piece of mind.

I've reinstalled the bottom cover and I'll do some bench testing to make sure all is well with this Pioneer Spec 2 power amplifier.

Crazy??? Ran 386 Watts per channel into a 7.5 ohm load at .0427% distortion That's my story and I'm sticking to it.

It's time to install the top cover. This Pioneer Spec2 power amplifier repair and restoration is complete. It's time for some music!