Mixer and buffer

[rasco22862]

Hi, i wanna build the ggg Mini mixer, but i read that there is some tone suck. So is there a mixer project without tone sucking?

Thanks

[Seljer]

put a buffer before each input?

[Mark Hammer]

Hi, i wanna build the ggg Mini mixer, but i read that there is some tone suck. So is there a mixer project without tone sucking?

Thanks

That mixer assumes you will be feeding it low-impedance signals.  The "tone-suck" is a question of using it improperly.  If you stick a buffer in front of any inputs where the anticipated signal is high-impedance, you will then be meeting the requirements of the circuit and glorious suck-free sound should emerge.

Note that you can always stick in a toggle to completely bypass any buffer stage if it should happen that you can supply the "ideal" signal to any particular input.

[rasco22862]

So, can i use 4 ggg IC buffers or JFET buffers? Wich one is more suitable for the mini mixer?

Thanks

[petemoore]

  Low output impedance, and high input impedance, usually not the other way around, tends to influence HF's first, may not be suitable for stuff, FF might not like it etc. Hafta try out this's and that's's or calculate what you need beyone the '10x ballpark' match or something else, like if you notice HF loss or HF becomes 'hard' or excessive.
  I guess thats sort of the basic idea, to the order of 10x difference usually works well, maybe you want a bigger 'x' on that or smaller might suit the need.
  I guess 'tone suck', it seems, has become the established and preferred synonym for 'impedance problem', [who-ever said that first?].
  doesn't really matter other than choose your input actives and resistors according to your needs.

[Mark Hammer]

I guess 'tone suck', it seems, has become the established and preferred synonym for 'impedance problem', [who-ever said that first?].

Don't know who said it first, but my sense is that "tone suck" initially came to refer to the cumulative loading of the guitar signal by those pedals using a SPDT switch (most frequently vintage pedals from the pre-1980 era).  That is, the loading effect of a buffer-less pedal whose input always remains in circuit, even when the pedal is ostensibly "bypassed".  Each pedal of this type in the chain "sucks" a little more of the tone away.  Imagine you have 4 pedals whose circuit input is always tied to the input jack, and each of whom have a 470k-1M terminating resistor on the input.  When the effect is on, it becomes difficult to notice the removal of input signal frequency content (how can you tell if a fuzz is experiencing loading issues?).  When the pedals are all "off", however, there is the equivalent of a combined parallel 120k resistance from signal to ground at all times (in parallel with whatever resistance to ground is posed by the pots), making the guitar itself, and its 6-8k pickups, difficult for the amp to "see".  Consequently, "tone-sucking" is a phenomenon which takes place when the effects are supposed to be off and exert no influence on the clean guitar signal.

That's not definitive, just my hazy understanding of it and how the term evolved.  The emergence of DPDT "true bypass" switching came to be one solution to tone-sucking, however the use of buffered designs using FET switching from some of the major Japanese manufacturers came to be another.