[Sergedc]

I have a pair of Shure Aonic 5 (34 ohm, 119 db sensitivity) and I am trying to have a noise free experience.

I have a Yulong DA8 II DAC, and using the headphone amp of the Yulong, I am getting a lot of noise / wind. This was mentioned in someone else's review (for sensitive IEM). Hence someone recommended that I buy a headphone amp with very low noise. The Topping L30 is rated at 141db SNR (and noise level of <0.3uV) , and in particular advertise being able to handle low impendence IEM.

The Topping L30 arrived and : the noise is huge and I can hear the radio! Details:
- In my bedroom (where I want to use it), when the L30 is connected to the Yulong (turned off!), the noise is big at the very low volume and high volume. Also, I can quite clearly hear the radio, especially at very low volume (the volume control is like fine tuning the radio channel). I have tried many position but it only helps a little. With I disconnect the RCA input cable the noise / radio is bigger.
- In my living room, it is much much better (at 25% volume it is actually dead silent). I can only hear the radio when the volume is turned all the way down. Also, when I put the amp on the floor (wood), on the TV console (wood) and on my body (flesh) the radio interference is bigger. When I put it on the printer (plastic), it is better.
- In other location I hear the "telegraph sound" in movie. Beeep bep bep beeep.

I guess someone will tell me that the Yulong is magnetically shielded and the Topping L30 is not?

How do I fix this? Can I build a faraday cage? If so how?
Do you thing the Topping L30 is defective?

Thanks,
Serge

 

[dunring]

I've had a couple of l30's and they aren't that sensitive. I'd check cables going to it to narrow it down if you have spares, or just removing the RCA to hear if it's picking it up anyway.If it's the unit picking it up, I wouldn't cover with anything that blocks heat dissipation.
Something as simple as a narrow monitor riser stand made of metal is cheap and gives a useful shelf over it if there's room on the desk. That's what I use, but on Etsy you could find a nicer shelf that's smaller.