Audio Splitter and stereo effects

[POTL]

Greetings
I want to learn about the safety of using stereo devices.
My friend wants to assemble a splitter and connect the guitar to the sound card and amplifier at the same time, if the splitter does not have a transformer, is it safe?
I heard that there is a possibility that the devices may go bad.
The sound card also has phantom power, can it accidentally turn on the amplifier?
At the same time, many pedal makers create stereo effects without transformers by simply placing buffers in front of the outputs.

[ElectricDruid]

I think there's a lot of variables in your questions that you don't have pinned down accurately enough to make them easy to answer.

I could answer your questions based on my assumptions, but that might not be your situation. Here goes anyway!

if the splitter does not have a transformer, is it safe?

I'd say almost alway "yes",  but there might be some situation I haven't thought of where "no" is correct. Mostly a wrong answer would just mean more hum than a right answer. There are lots of ways to design a bad splitter!

I heard that there is a possibility that the devices may go bad.

I doubt it. That would have to be a *really* bad splitter!

The sound card also has phantom power, can it accidentally turn on the amplifier?

If any device is outputting phantom power, this is something important to know about. 44V is enough to fry most typical pedal circuits,  so watch out!

At the same time, many pedal makers create stereo effects without transformers by simply placing buffers in front of the outputs.

There  is no connection between "transformers" and "stereo effects". Indeed, *most* stereo effects do not use transformers. "Stereo" only means that it provides different signals to the 'left' and 'right' channels. There's nothing implied about transformers at all.

HTH,
Tom

[POTL]

Hi
Thanks for answers.
I cited stereo effects as an example, since they allow you to split the signal into 2 parts and send it to different amplifiers.
I heard that there is a possibility that the amplifiers can be damaged by connecting them to one splitter.
At the same time, I see that the music industry consists mainly of simple and affordable devices that do not use transformers, JHS buffers, inexpensive stereo effects, BOSS and MXR.
I understand correctly that you don't have to worry about connecting to a different device and spoiling them, because different amplifiers are designed differently, this also applies to power supply, maybe the nominal earth will be at different levels.
What good splitter designs without a transformer can be safe for devices and give a minimum of noise.
Is there a way to protect devices from phantom power? (Suddenly, someone accidentally turns it on).
Should I put low resistance resistors between jacks and ground?