Adding effects loop into pedal and avoiding ground loops…

[LukeFRC]

I’ve searched, I’ve googled and lots of things about isolated power come up…

If I wanted to add a switchable send return loop to a pedal design… presume buffer on send and return to avoid any impedance issues - is transformer isolation needed to avoid ground loops?

Thinking of combing an input buffer-loop-end of chain preamp/di into the same enclosure

 

[LukeFRC]

I fully realise this will be covered on a thread or page somewhere obvious online that I haven’t found

 

[jwin615]

Use an isolated jack for the send and put a ground lift for said jack on a switch. Done.

 

[LukeFRC]

Use an isolated jack for the send and put a ground lift for said jack on a switch. Done.

Oh! I thought it would be more complex that that!

 

[darwin999]

You always need exactly one ground.
So do as @jwin615 says with a separate ground (e.g., from a grounded power supply).
Or, use regular cables (which ground the boxes to the amp's ground) with individually isolated power supplies for all the pedals.

Added note:
Ground loops are formed when you have more than one ground in the overall circuit (the overall circuit may encompass your amp plus connected pedals). And having no ground also leads to noise from induced ac noise pickup.