Passive DI Box is this right

C

captain

Active member
Is this the correct way to wire up a passive DI box with ground lift and a -15db and -20db pad. As I can work it out this is the direction ChatGPT has given me on, but not 100% sure I total trust my interpretation (or there instructions). Main switch is a DPDT On-On-On

Thanks

Di Box 3.jpg ​
 
Last edited:
-25dB? What are DIing?!?
Anyway, looks okay at a glance. Be sure to use an isolated/insulated jack or it will defeat the ground lift. Careful that the ground to the transformer body doesn't defeat it as well. And ditch the ground loop between the transformer and - input.
Will whatever you are plugging in be happy with a 1k input impedance?
Oh, and be careful with type 1 vs type 2 DPDT. I think this is drawn for type 2 from the looks of it.
 
jwin615 said:
-25dB? What are DIing?!?
Anyway, looks okay at a glance. Be sure to use an isolated/insulated jack or it will defeat the ground lift. Careful that the ground to the transformer body doesn't defeat it as well. And ditch the ground loop between the transformer and - input.
Will whatever you are plugging in be happy with a 1k input impedance?
Oh, and be careful with type 1 vs type 2 DPDT. I think this is drawn for type 2 from the looks of it.
Click to expand...
Thanks for the feedback. Am I using a 25db pad? Which of the 2? Those DPDT switches have really fried my brains. Going to use the Di box with line level and get the impression that the 1k resistor will be ok for that. Will take the transformer out of the ground.
 
Your diagram is incredibly hard to follow, but a couple things jumping out:
  • you have a 1k from input to ground, that along with your 10k series resistor is going to strangle your signal quite a bit right off the bat before you even hit the switch
  • you have redundant connections from your input jack ground to the transformer primary ground; not a huge deal, but it's one more line in a mess of lines
  • I don't quite understand your logic with the switch connections; for example I don't get the reasoning for the connection between lug 2 and 3 on the right side
  • Not all D.I. transformers have a connection on the secondary side for the chassis ground, so depending on your transformer pinout that could kill the whole signal
Do you have a transformer picked out for this already? That will determine a little bit of how you should be hooking it up.
 
vigilante398 said:
Your diagram is incredibly hard to follow, but a couple things jumping out:
  • you have a 1k from input to ground, that along with your 10k series resistor is going to strangle your signal quite a bit right off the bat before you even hit the switch
  • you have redundant connections from your input jack ground to the transformer primary ground; not a huge deal, but it's one more line in a mess of lines
  • I don't quite understand your logic with the switch connections; for example I don't get the reasoning for the connection between lug 2 and 3 on the right side
  • Not all D.I. transformers have a connection on the secondary side for the chassis ground, so depending on your transformer pinout that could kill the whole signal
Do you have a transformer picked out for this already? That will determine a little bit of how you should be hooking it up.
Click to expand...
Thanks for replying. I'm pretty confused, but thought the second was right. So any help would be appricated as I tried to get info from AI. The transformer is one of these LINK as I got it pretty cheap from Aliexpress. Basicly I want the DI to have ground lift and a -15db and -20db pad. I'm not going to use it with a guitar, but line level for my sampler. I already have a DPDT On-On-On.

Sorry about the confusion with my drawings, but I am dyscalculia as well as dyslexia so find it hard do work with numbers and symbols. I need to visualise electronic more like a picture, and it can be a bit harder for me to understand concepts compare to others.

Thanks again
 
Last edited:
You must log in or register to reply here.
Back
Top