Usable VM mod

[TonyC]

Interesting Dean!
It's probably possible to tune it exactly to how we want it, but maybe it requires changing a lot of components to get the "sum" right.

[jannne]

Do you have the mid boost always on? What about increasing the c2 and turning the mid boost off?

[TonyC]

Do you have the mid boost always on? What about increasing the c2 and turning the mid boost off?

I have mid boost OFF pretty much all the time so I don't think I want to change the character of that mode. But now and then I need to engage the mid boost and I kinda like what happens, but it's just too much of it.

[SteveD]

With LP-filters if you increase the cap value and reduce the resistor value...you will get the same frequency response but more gain. so this might be an option but i dont know how it would affect the rest of the circuit?? Steve? if you increase C7 and reduce R8 this should keep the same frequency response and increase gain at those freq' yes? at appropriate values for R8 and C7 obviously! say 150K for R8 and 470p for C7. would this work steve?

Altho C6 would have to be changes also then so that when midboost is off, the change in resistance wud not change the frequency rollof. i was also thinkin that r9 might need to be changed to counter for the extra current produced by dropping r8 but would doing that then affect the gain of the midboost and cancel the effects?

this is just me thinkin out loud!! and wondering could this work!!

Am I right in thinking you actually want more low frequency gain than the amp already delivers with the 'Body' turned to max and the 'Mid Boost' engaged?

Filter responses are also affected by inter-circuit impedances and their interaction thereof. Most filter theory gives examples with ideal world settings or at least buffered inputs and outputs. The Vintage Modern's circuit is carefully balanced with respect to this interaction and it is essential that whoever decides to modify component values has a full understanding of the implications as a whole. In other words, if you're not sure what you are doing, changing one component value can have an unintentional knock on effect elsewhere in the circuit.

[DeanM]

With LP-filters if you increase the cap value and reduce the resistor value...you will get the same frequency response but more gain. so this might be an option but i dont know how it would affect the rest of the circuit?? Steve? if you increase C7 and reduce R8 this should keep the same frequency response and increase gain at those freq' yes? at appropriate values for R8 and C7 obviously! say 150K for R8 and 470p for C7. would this work steve?

Altho C6 would have to be changes also then so that when midboost is off, the change in resistance wud not change the frequency rollof. i was also thinkin that r9 might need to be changed to counter for the extra current produced by dropping r8 but would doing that then affect the gain of the midboost and cancel the effects?

this is just me thinkin out loud!! and wondering could this work!!

Am I right in thinking you actually want more low frequency gain than the amp already delivers with the 'Body' turned to max and the 'Mid Boost' engaged?

Filter responses are also affected by inter-circuit impedances and their interaction thereof. Most filter theory gives examples with ideal world settings or at least buffered inputs and outputs. The Vintage Modern's circuit is carefully balanced with respect to this interaction and it is essential that whoever decides to modify component values has a full understanding of the implications as a whole. In other words, if you're not sure what you are doing, changing one component value can have an unintentional knock on effect elsewhere in the circuit.

No not me, some one else said they liked the frequencies that get boosted and would like more boost on those frequencies, rather than adding more low end.

As regards to the rest, i said i dont know how it would affect the rest of the circuit and thats why i was interested in what you would say! cos im doing electronics is college. So that stuff you mentioned about the inter-circuit impedances and their interaction was interesting! I wanna learn more about what goes into a guitar amp! im fascinated by it!!