The morphing textures of a bad mixer. (solved)

[stonerbox]

Educate a fool! I know two 10ks into one output stage would do the job... but I am curious as to why this design is so bad? Whenever I dig in hard on the strings the two output stages seemingly starts to fight for pole position and the otherwise good sounding distortion gets this strange out-of-phase-like morphing texture to it.

[blackieNYC]

It may be just that - are your two sources out of phase?  Can you tie the inputs together and connect just one source?

[stonerbox]

It may be just that - are your two sources out of phase?  Can you tie the inputs together and connect just one source?

They are not out of phase. If I discard the gain stages and tie them together (HPF + LPF) with two 10k resistors everything sounds just fine, except for the very low output.

Ok, I am stupid. They are out of phase BUT WAIT there is more! Sheeesh...

Sorry for wasting your time!

[blackieNYC]

Is this the complete schematic?
Might not matter at all, but why the different cap values?

[antonis]

BTW, I'd use pots for R42 & R43 with respective lugs 1 grounded and wipers connected to C33..

[stonerbox]

Is this the complete schematic?
Might not matter at all, but why the different cap values?

They are out of phase (LPF + HPF). When the two filters comes together they effectively cancel out each other's opposite area and gives me an option to lower or raise the bass. As long as they are directly tied together everything works fine but with the gain stages separating them (+loading down the filters) it messes with the center frequency. At least that is my guess. Can't believe I was this oblivious. I've been at it for far too many hours today and my brain is slushy mush.

[ElectricDruid]

If you've got that many op-amps already, why aren't you using an active inverting op-amp mixer? If the extra inversion on the Bass channel is crucial, make it a differential mixer. The two transistors followed by a passive mix seems unnecessarily complicated to me, as well as less than ideal.

HTH,
Tom

[stonerbox]

If you've got that many op-amps already, why aren't you using an active inverting op-amp mixer? If the extra inversion on the Bass channel is crucial, make it a differential mixer. The two transistors followed by a passive mix seems unnecessarily complicated to me, as well as less than ideal.

HTH,
Tom

And ditch the generic and beautiful sound the mighty BC549?? Over my dead body!

[ElectricDruid]

And ditch the generic and beautiful sound the mighty BC549?? Over my dead body!

Lol, fair enough!

[stonerbox]

I have another related question to mixing these signals. Maybe I should have started a new topic but I'll post it here anyway.

It is a stereo effect with the goal of switching the bass from either the left or right side into both outputs. Always bypassing either left's or right's lower bass frequencies.

In the example below only the left's bass output is feed out of both L and R.
Question: Will I run into problems if I route them like this? Routing the bass out of one side through individual 10k resistors?