Ok, I've got my Aleph-X working and now I need a better pre. So I looked around and compiled a few designs into my own design, which is really pretty standard. But there are few things about the general design of the circuit that I would like to understand better.

I have attached a schematic which I will refer to in this post:

First question: How do I calculate the gain of a SuSy line stage? I would like to get at least 10 db of gain, and have it adjustable up to about 20 db (just like the original bosoz). R21 and 22 are the feedback resistors and I just copied the value from some other designs I looked at.

Question 2 relates to the above question: are the values of P5 and R15 also the correct values to get the required gain adjustment? Since the values in my schematic are lifted straight form the BZLS article, I'm guessing something will have to be changed since the feedback resistors will reduce the gain. Once again I don't know how to go about calculating the gain.

Question 3: Are the input and output pots the correct values and configured the correct way for optimal input/output impedence and performance. I will most likely use ladder type attenuaters for the both input and output.

Q 4: I am using the dual CCS approach because I would like to have adjustable gain. Can someone tell me if this design is appropriate for this circuit? Also, are the values of R3 and 4 correct in order to get about 40mA through each leg. This is exactly the same current source I used for my aleph-x. It's a 9.1V zener bypassed with a .1uF film cap to reduce noise and a J505 1mA current regulator as a supplemental stabilizer to keep the current through the zener constant. Anyone used one like it?

Hope you all can help, I believe my current pre is inadequate to get full performance of my new Aleph-X, and I would like to change that as quick as possible!

I have attached a schematic which I will refer to in this post:

First question: How do I calculate the gain of a SuSy line stage? I would like to get at least 10 db of gain, and have it adjustable up to about 20 db (just like the original bosoz). R21 and 22 are the feedback resistors and I just copied the value from some other designs I looked at.

Question 2 relates to the above question: are the values of P5 and R15 also the correct values to get the required gain adjustment? Since the values in my schematic are lifted straight form the BZLS article, I'm guessing something will have to be changed since the feedback resistors will reduce the gain. Once again I don't know how to go about calculating the gain.

Question 3: Are the input and output pots the correct values and configured the correct way for optimal input/output impedence and performance. I will most likely use ladder type attenuaters for the both input and output.

Q 4: I am using the dual CCS approach because I would like to have adjustable gain. Can someone tell me if this design is appropriate for this circuit? Also, are the values of R3 and 4 correct in order to get about 40mA through each leg. This is exactly the same current source I used for my aleph-x. It's a 9.1V zener bypassed with a .1uF film cap to reduce noise and a J505 1mA current regulator as a supplemental stabilizer to keep the current through the zener constant. Anyone used one like it?

Hope you all can help, I believe my current pre is inadequate to get full performance of my new Aleph-X, and I would like to change that as quick as possible!