Sansamp GT2 - questions

[caspercody]

I just got done building the GT2, using a PCB from Small Bear (which is a great PCB), and the PCB is based off of Tonepads layout (http://www.tonepad.com/getFile.asp?id=112).

I added a 3PDT switch to add in the mid band EQ, as posted by Mozwell in this post.

I inserted the switch between IC4b pin (7) outout and the 1K resistor (going into Q1 base).

The switch also switches the 330pf (C8 in the mid band EQ schematic), so I can keep the GT2 tone control normal when I switch off the mid band EQ.

When I first tried this, with the switch in the normal mode, the pedal sounded bad. When I switched in the mid band EQ, the pedal sounded really good, and some of the squealing with the gain turned to max went away. But why did it sound bad in the normal position.

So I connected the last switch of the 3PDT to switch on the power to the mid band EQ.

Now in both the normal, and adding the mid band EQ the pedal sounds really good.

Some questions:

When I switch the 3PDT switch to either position, I get a pop. It did not do this pop until after I connected the power to be switched? Should I put a cap across the switch terminals to get rid of pop?

In normal mode, with controls maxed it is very noisy (which reading on line is happening a lot to this DIY pedal). I am going to try to wrap shielding around some of the wiring, but my question is do you connect one end to ground? Is there a article about properly shielding wiring?

Thanks
Rob

[caspercody]

Sorry, I copied this from a different forum that I posted it on and realized this last night that I have information in my post that might not make sense. Here is a lionk to the mid band EQ:

http://www.freestompboxes.org/download/file.php?id=6989&mode=view

Thanks
Rob

[caspercody]

http://www.freestompboxes.org/download/file.php?id=6989&mode=view

That last paste did not work, hope this one does

[caspercody]

www.freestompboxes.org/download/file.php?id=6989&mode=view

[caspercody]

We we not allowed to type in the other sites web address?

http://www.free*stomp*boxes.org/download/file.php?id=6989&mode=view

[bluebunny]

We we not allowed to type in the other sites web address?

Nope, no matter how many times you try.   

[potul]

In general it's a bad idea to switch power on/off of any circuit on the fly. This will always make noises...

The usual way of working is to have everything powered up, even if not in use, and use the switch only to put the EQ in the signal path or not.

It's the same question that has been asked multiple times regarding powering on/off the pedal when in bypass. Bad idea.

Mat