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Mixer from pre-amp design

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Hi there,

Having just (pretty much) finished refurbishing my amp, I'm looking to start my next project, which is building an audiophile-grade two-channel switchable MM phono and line input mixer.

Having looked through the web and a few "sound practices" magazines, I have decided to use Jan Lodström's REMUS design, largely as it seems fairly straightforward to build. Over the next few weeks I will be asking a few questions which I hope you can help me with.

First question is, do you think this is a good design for what I want to do? Keep in mind that I couldn't care less about built-in EQ. In fact, I am keen to not have any, in part because I want to keep the sound as "natural" as possible when I listen and mix at home and in part also because I intend to build by-passable send-receives for each channel (or for the whole thing - have not decided yet) and use an outboard isolator if and when I DJ at parties or when I record a mix (the only two times I am really interested in using EQ).

Second question is more technical - where would you actually add the "summing" part in the design. After asking people in the forum, I was advised to "sum" the two signals by using two resistors. The question is, do I build two pre-amps and add the resistors at the end, or do I build two of the section up to the potentiometer and then hook them up to one final stage with resistors? If this sounds confusing, I have attached a schematic of the amp with some notes, which should make my question clearer. I would also appreciate some advice on how to decide what the right resistor value to use is.

That's all at this stage. Will be coming back with some questions on the power supply, but this best left for a separate thread.

Thanks!
Nikos
 

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