Mr bassman 100

[keysersoze808]

hi..
im replacing master vol. 1M pots on my bassman 100 head, but currently dont have stock 1Mpots so decided to replace it with 10k pots.. but the result was i get less volume(loudness reduce) ,iam quiet confius due to my thought was less resistance(10k) yield more volume??
any thought would be appreciated .. thanks

[Enzo]

You have the Bassman 100 combo from abuot 1999? My schematic shows the master volume as 100k.

Maybe you have the Bassman 100 from the CBS era around 1971? That has 1M pots. Did you replace all three volumes? Or just the master? In either case, less resistance does NOT mean more volume, it means exactly what you got. Resistance by itself means nothing. It matters what the other parts in the circuit are and what its job is with them.

In the case of your master volume, the two channels are mixed together through a pair of 220k resistors to the top of that 1M pot. They will form a voltage divider with the [pot. Changing the pot to 10k instead of 1M seriously upsets that divider, drops the output by a factor of about 20.

You need a 1M pot. A 2M pot would work, got one? A 500k would be a lot better than a 10k, any help there?

[keysersoze808]

thanks enzo..
ill try replacing it with 500k pot and see if theres a diff. mine from the cbs era.. also iam planning to add trimpot to adjust bias.. replacing the 15k resistor at the bias balance pots.. ill report back later..