McIntosh MC 2505 Repair And Restoration

This McIntosh MC 2505 solid state power amplifier is in pretty good cosmetic shape except for the wood cabinet. 

The chassis of the McIntosh MC 2505 is out of the case. Time to get decades of dust and dirt cleaned out

The original wood case of this McIntosh solid state power amplifier is pretty beat up.

The image below shows a close up of the bottom right hand corner of the case. The area of the deepest scratches. 

The image below shows the same area of the case after some sanding.

After using some Howard's furniture polish the wood case for the McIntosh MC 2505 looks much better.

The knobs have been removed for cleaning.

The glass has been removed for cleaning.

Need to clean the inside of the glass also.

Some sticky debits on the diffusion panel that I removed with Q-tips and alcohol.

This McIntosh MC 2505 solid state power amplifier has a nice blue glow when you get the dirt removed from the meters.

Warm water, dish soap and a toothbrush is the difference between the cleaned knob to the left and the dirty one to the right.

Changing out the old bulbs is a good idea. Fortunately this McIntosh MC 2505 uses inexpensive bulbs that are readily available.    

The McIntosh MC 2505 solid state power amplifier is shown with it's bottom cover removed.   

With the bottom cover removed there is easier access to some controls for cleaning with deoxit. 

Four of the bulbs used in this power amplifier are easily accessed when the bottom cover is removed. 

With a steady sine wave signal input into both channels the power meters at all ranges showed a slight difference between the channels.

 There are two pots on the meter circuit board of the McIntosh 2505 amplifier that allows you to calibrate the left and right power meters.

The filter capacitors tested out fine but after 40+ years but there is no question that they have functioned far longer then they were designed to.

Now I'll check the operation of the amplifier, dc offset, power output, distortion and just the general functioning of this McIntosh 2505.

Everything on the test bench checks out fine and it's about time to put everything back together.

The MC 2505 power amplifier chassis is back in the wood case and it's time to give a final listen on the test bench.

This amplifier is ready for some music. This McIntosh MC 2505 power amplifier repair and restoration is complete.