Vintage speaker enclosures - help needed
I inherited a pair of speaker enclosures, custom-made by a relative in the early/mid 1970s. This photo of the crossover units shows what the drivers are.
https://theartofsound.net/forum/atta...5&d=1655714260
On the back of each speaker there's a small cream knob which has two positions only - it's under the crossover wiring loom in the second photo.
On the back of one speaker, there's a larger clear dial which has four positions.
https://theartofsound.net/forum/atta...6&d=1655714270
I tried the knobs in different combinations and there was some difference to the tone but when I turned up the volume, the amp started misbehaving (power light flashed on/off, one channel stopped working temporarily). It's an old backup amp (Denon PMA-355UK) and these problems might be unrelated to the speaker controls - just coincidence.
I have no idea what the different knobs might do - can anyone offer suggestions/advice?