This reply isn’t so much for you but for a future search for future potential owners.
When you use Bluetooth you do:
- the original digital media is passed immediately to the headphones over a digital Bluetooth signal
- the headphones take that digital input, apply a volume alteration per frequency range as per the EQ settings
- inserts anti-sound if applicable so ANC works, this takes sound from microphone and adds the opposite sound to the EQ so cancelled noise.
- converted to analogue
- pass this as analogue signal to the drivers along a very short soldered wire within the headphones.
When you use wired:
- the digital signal converted to analogue
- passed along a much longer plugged in wire
- to the drivers in the headphones
So the sound is totally different and wired is reliant on the soundcard in your PC, the quality of the audio socket, the cable. It also stops ANC from being possible.
What the Q35 implicitly did wired was:
- added an analogue to digital converter in the headphones
- this is then fed through the same EQ that Bluetooth path would do
- this also allows ANC to be inserted
- converted back to analogue
- then to the drivers
This extra pathway then allowed other sound alterations such as inserting ANC etc as it inserts the inverse sound from the microphone to cancel noise.
This is why Q35 costs more, it physically has more electronics, and is a better choice wired.
I hope this informs a future search prior to purchase so the owner knows it’s their fault if Q30 sounds bad wired. You’d choose wired because your source is good quality and your source can do EQ alterations.