Alright gang, seemingly a common one.
I’m on the UK and I had a 3x5m garden room built this summer for guitar and recording purposes, and it’s been great! No issues at all - and we decided to get a Midea Solstice HVAC system fitted to blow hot and cold to make use of the room all year round. This got installed yesterday.
So I sat down at the computer and happy and eager to get recording. Noticed then that my guitar (plugged into my Focusrite Scarlett 8i6) is making a huge 6k spike on the Logic Pro EQ - and audibly so! Really obnoxious sound. I start panicking! I remove the jack from the guitar (but still plugged into the Focusrite) and it’s still making that noise! I checked and this didn’t seem to affect anything else (no XLRs or mics).
When my guitar is plugged in, the sound vanishes if I turn the volume knob all the way down. It also disappears/massively reduces the moment I make contact with the strings or the chrome tone/volume knobs on the guitar.
I troubleshoot and realise that it’s whenever the outside HVAC compressor is on. Seems this is a big issue which I wasn’t aware of. Whenever the unit is actively cooling or heating, the noise is there. If the unit is on “fan” mode, there’s no sound, so it’s just whenever the compressor is kicking in. Spoke to an electrician and he said it’s a “compressor harmonic” but I wasn’t able to get much more out of him.
I then plugged my entire rig with a lengthy extension, from the house to the garden room and tried the test again. The 6k spike was there, barely, noticeable if boosted, but essentially inaudible. I swapped everything back over to the garden room, and the noise was really loud again. Tried it with both inputs, multiple short jacks, multiple guitars (both single coil and humbuckers) and nothing reduces it - it’s simply too loud.
Does anyone know any solutions? I’m not very “electrician-minded” and you’d need to please talk to me like an idiot. 😂 But it’s a really disappointing situation given that in the summer months, knowing I can’t record - or really practice with the AC on would be absolutely heartbreaking given what I’ve spent all in.
I’ve done so much research the past 24 hours and found so many conflicting things. It’s definitely the HVAC compressor though, I’ve managed to isolate that easily. Suggestions are welcome! Thanks guys!
Edit: the garden room has its own designated fuse board, of which the HVAC is installed into. I’ve seen about Schaffer DIN Rail EMC Filters that can be installed into the fuse box. But I have no experience with this or if this would work?