Noise through headphones when pre-out is in use?
Apr 11, 2020 at 11:54 PM Thread Starter Post #1 of 1

Aaronz101

New Head-Fier
Joined
Apr 10, 2020
Posts
2
Likes
0
Location
Australia
Hey guys,

I'm currently running a set of Beyerdynamic DT990 Pros through a FiiO E09K desktop amp. RCA input to the amp is from the rear 3.5mm jack of my computer. This setup normally works fine and has no background noise even when the amp is cranked up high.

I recently introduced a set of JBL LSR305p MKII speakers to my setup, and I'm feeding them from the amplifier's pre-out using RCA to 1/4" TRS cables. This is where the problem started.Whenever the pre-out is connected, my headphones suddenly become noisy when there's any decent volume going through them. This even happens when the speakers are powered off, as long as the pre-out jacks are occupied. The noise gets worse if my computer is doing anything intensive like playing games. The noise seems to be directly related to what my computer is doing (e.g. waving the mouse around adds to the buzz). Weirdly, there's no such noise through the speakers themselves.

My current solution is to unplug the pre-out whenever I'm using headphones and plug them back in (and remove the headphones) when I want to use the speakers, but it's a bit of a pain. Does anyone recognise this type of issue and know how I might fix it? It seems like having the pre-out connected is somehow amplifying the EMI noise from inside my computer which is normally inaudible (since doing stuff on the PC directly affects the noise).

I'm considering replacing my E09K with a FiiO K5 Pro DAC/AMP to try and fix the issue. Would this help at all? I'm hoping that moving away from my PC's inbuilt DAC might clear things up if EMI is the issue. Either way, I figure that the K5 Pro should be a worthwhile upgrade over the E09K anyway.

Greatly appreciate any and all input!
 

Users who are viewing this thread

Back
Top