Have you seen this Threshold SA/3 upgrade before?

[uberchurl]

I acquired a Threshold SA/3 amp and it has an upgrade that I am not familiar with. I would like to know if anyone can shed some light on this upgrade shown in the photos below. I am not sure I understand the function of this upgrade; it appears to be a separate capacitor pack . This is my first encounter with Threshold amps, so I am pleading ignorance at the moment.

Thanks

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

 

[Nelson Pass]

It appears to be an auxiliary capacitor bank. Looks nicely done.

😎

 

[uberchurl]

Sorry, I'm new to Threshold amps. Could you explain the use of a capacitor bank?
Thanks

 

[Nelson Pass]

Capacitor bank stores DC power created by the power transformer and
rectifier bridges.

They all have one, but this owner wanted a bigger one.

😎

 

[uberchurl]

Mr. Pass, thanks for the quick, informative response. By the way, the SA/3 sounds pretty stunning with my Khozmo passive preamp.