Impedance and multing Q for Craig

[c.cash]

... or anyone else that wants to jump in... I have posted this question on a few other forums with no response. Since, while researching the topic, I keep digging up articles by you... I thought... The XLR inputs of my mixing board are 3kOhms, and the TRS inputs are 10kOhms. When I mult hi-impedance sources at my patchbay, I run into impedance loading using the mixer's 3k inputs simultaneously with my digi 001's 1 and 2 inputs, which are also 3k. The resistance from multing will be 1.5k, way below optimum for a keyboard with an output impedance of 2kOhms, for example. I'm losing signal and frequency response. I know the obvious option is to not use those inputs... but you only get 8, and I have a lot of line-level sources. My idea is to place a direct box before each of the digi 001's 1 and 2 inputs (these inputs have built-in mic pres). This will bring the impedance from the mults down to a "better" level, but I'm wondering about the trade-offs. The direct boxes are passive. Since I don't really need the level stepped down to mic level, perhaps a -10 hi-z to +4 lo-z converter is the better solution? (they are more expensive than the cheapie DI's though). What would you do? Do you have any product recommendations (touchy, I know), or are there better alternatives? Thanks! Curt

[Ethan Winer]

Curt, It sounds like you're connecting a keyboard's line level output to the console's mike level input, yes? If so, that's the problem right there. You should connect to the 1/4-inch line level input! I don't have a Digi 001 so I don't know its features. But you want to avoid using its mike preamps too, and if possible use a line input. --Ethan

[c.cash]

Seriously, thanks Ethan, but if I had available line level 1/4" inputs to use, believe me I would.

[Anderton]

There's an easy technological fix for doubling up the number of devices you can feed into each 1/4" input, but you lose a little level. Here's the deal in a nutshell (adapt to your own needs). Get a small box and mount three 1/4" jacks. Label two as Input and one as Output. Solder a 5.6k resistor from one input to the output, then solder a second 5.6k resistor from the other input to the output. These resistors keep the outputs from interacting. This lets you double up devices such as keyboards; use their volume controls to balance the two.