Tone control question

[Stainless Stan]

Hello, a happy owner of Acoustic 220 head/402 cab stack here
I bought them used and fell in love at first sight and first note. Everything works fine, the tone is nice and clean but... the bass tone control on the amp is not working.
I re-soldered some critical joints to no effect.
I guess, my question is very simple. If the tone control is not working does it mean that it's always in flat position, neither boosted not clipped? If that's the case I would probably just keep shaping the tone with the amp's graphic EQ or add a pre-amp/eq in the loop.
Should I be bothered or should I leave it as it is?
Please advise

 

[beans-on-toast]

It sounds like something in that circuit has failed. It should be a simple fix for a tech. One possibility is that the pot has failed and needs to be replaced.

The bass tone control goes from the pot’s wiper through an inductor to ground. All those solder joints need to be rechecked. The chances of the inductor failing in that circuit are low. Look to the pot, it can be removed and tested.

How the bass tone circuit is performing in terms of the flat position depends on where the issue is.