[eatlife]

Hi , I am constructing a 24 channel passive summing mixer. The design is basically the new york dave schematic , no level pot just the mbb pan switch.1/2 watt 1% metal film resistors throughout, the only change is I got a whole bunch of transformers from an mci console about 40 1:1 600 ohm and about 30 10k balanced to 50k unbalanced -8 db (or line in ) . My question is, I have tried passing audio with the 1:1 at summing mixer input feeding the pan with success, I just can't get the pan right (3db down at center) in the schematic it uses 4.3 k resistors to achieve center, is there a formula to calculate what I should use there? where do I find it? . also is using the 1:1 my best option?I would like to use the parts i have. My sydec ibox24 ch ad/da outputs are rated as variable /110 ohm nominal output impedance. thanks