I had a few trivial questions about tube preamps. I understand that the forum is dedicated to stompboxes, but I am sure that competent people will help me.
I looked at the scheme of the preamp EVH 5150 III, which is a modernized version of the Peavey 5150/6505.
I have a few questions
1) In most preamplifier circuits, there is a voltage divider in front of the triode; however, before the V5-A, the r66 + r67 design resembles the input circuit of vintage amplifiers, what is called such a connection, what are its pros and cons, how can the influence of resistors on the volume drop be calculated (in the divider voltage can always be calculated on how many decibels volume falls).
2) V6-A is Triode with Local Negative Feedback, as far as I understand the gain is 1, and the bandwidth of the frequencies is very high, the input impedance is high and the output is low. A logical question arises: what advantage does this construction have with a classic buffer? Buffer is easier to perform and requires less detail, just so no one would complicate the scheme.
3) V6-B is a buffer, why is it needed if its functions are performed by the previous stage?
4) Do resistors R7 and R8 affect the gain of V2-A or the nominal does not play a big role?
For example, if I change the value of 270 to 470, the gain will be less?
5) Do the resistor values in the voltage divider affect the gain?
For example, a pair of R47K + R47K and a pair of R470K + R470K will give the same voltage drop of 6dB or will the resistance value further affect the overall gain?
6) In Mesa Boogie Mark amplifiers, the output stage looks very interesting, there are several voltage dividers at once, which give a strong signal drop, what is this for?
