I’ve just completed an overhaul of my Penta MK2’s. Here’s what I’ve done to date:

• Refoamed mid ranges
• Cut off spade connectors and solder wires directly to speaker terminals
• Replaced electrolytic capacitors on filter boards with Audyn MKT capacitors
• Cut off spade terminals and solder wires to crossover boards.
• Change wiring so that each crossover board connects directly to speaker terminals at the base.

And for the Amplifier in the base:

• Replaced capacitors in audio path with Wima caps
• Replaced all other electrolytics with Nichicon 105 degree caps except the 10000uF caps which I replaced with Cornell Dubilier units.
• Replaced (in my case) the TL072 opamp with OPA2134
• Replaced trimmer resistors with Bourns cermet trimmers

Adjusting the idle current was a bit fiddly as the replacement trimmers could only be adjusted from one side. So that meant having the transformer out lying on its side while I adjusted the trimmer and someone else measuring the voltage.

So where to from here? Any other tweaks or mods to consider that others have done?

The Pentas are connected to a BM7000 so perhaps that is the next project? Any suggestions on this?