Guitar Headphone amp with distortion schematics

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Hey guy,
I know I'm probably becoming a bit of a nuisance, but I have gotten really excited about these little amps I'm making and I have designed a schematic to add a distortion channel and was wondering if you could take a look at it and see if any problems jump out at you.

I know the buffer, the main amp and the power supply work because I've built several of them. I am concerned about the distortion path and if the numbers and positioning of the components looks OK.

Here is the schematic that I drew up. I have used other peoples ideas for designing this and I in no way take credit for their ideas.
 

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My first thought is why the buffer at the front? - make R5 1M and connnect the input directly to C3. You can then use the now unused half of the opamp for the second amplifier stage.

But your gains are completely wrong, a gain of only 11 on the input stage, and a gain of 1001 on the second stage, which you're feeding with 0.7V p-p - how do you expect to get 700.7V p-p out of the opamp?.
 
Man, as always thanks for the reply. I did the buffer because the guy that was helping me initially in the chip amp forum said that was the way to go (because of the impedance of the guitar I presume). I am just starting to get a basic idea of what these components do.

I found a site that gave me the calculations for the gain, but how do I determine what is a good starting point. The power supply to the first amp is 4.5v, right? so if I use the .7 volts that the 2 diodes are limiting me to, would I divide the 4.5v by .7v and use the 6.42 that I get from that equation to multiply the gain of 11 by resulting in a gain on the second amp of roughly 71? Or am I completely off base?

Like this?
 

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Nope, just got to reading what I wrote there and it doesn't make sense at all. I am using two different values with the 4.5v and the .7v.

I just keep getting myself more and more confused. Please don't give up on me I really would like to learn this basic stuff and I believe that the best way for me is trial and error and asking a lot of questions.:rolleyes:

Thanks

EDIT: OK I have been doing some more reading on this an I realize that its a lot more complicated than I gave it credit for. I don't have a clue how to calculate the values for the various components, and the values that I have been using are from others schematics. I am going to keep trudging through this though until I get a working amp!
 
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