Bottlehead Forum

Bottlehead Kits => Eros Phono => Topic started by: kill_surf_city on October 22, 2022, 03:02:12 PM

Title: Possible low level hum?
Post by: kill_surf_city on October 22, 2022, 03:02:12 PM
It’s unnoticeable when music is playing, but when the amp is on and nothing is playing there is a very quiet low level hum. Even with the volume turned all the way down. It’s not a big deal since it isn’t audible when music is playing. But how much hum is normal? I do have SUTs installed so maybe that’s part of it? If this is indicative of a problem, what should I look for?
Title: Re: Possible low level hum?
Post by: Paul Birkeland on October 22, 2022, 04:37:13 PM
If the volume is turned all the way down at your preamp (or integrated amp), then that rules out the phono setup itself.  What's in the rest of your system?
Title: Re: Possible low level hum?
Post by: kill_surf_city on October 23, 2022, 03:47:51 AM
If the volume is turned all the way down at your preamp (or integrated amp), then that rules out the phono setup itself.  What's in the rest of your system?

I have an integrated Jolida 102B. When I remove the RCA plugs from the Eros the hum goes away. Maybe it’s a grounding issue? I did just move into a new apartment so maybe that’s the issue?
Title: Re: Possible low level hum?
Post by: Paul Joppa on October 23, 2022, 04:47:56 AM
Did you remove the RCA plugs from the input (turntable), or those from the output (to the Jolida), or both? Is there a ground wire from turntable to Eros?
Title: Re: Possible low level hum?
Post by: kill_surf_city on October 23, 2022, 04:50:01 AM
Did you remove the RCA plugs from the input (turntable), or those from the output (to the Jolida), or both? Is there a ground wire from turntable to Eros?

No I left the RCA plugs from the turntable plugged in. I unplugged the ones going to my Jolida and the hum goes away. I do have a ground wire connected from my turntable to the Eros
Title: Re: Possible low level hum?
Post by: Paul Joppa on October 23, 2022, 05:54:25 AM
Repeat the experiment with the Eros turned off. That will help determine whether it's a ground issue.
Title: Re: Possible low level hum?
Post by: kill_surf_city on October 23, 2022, 12:11:31 PM
Repeat the experiment with the Eros turned off. That will help determine whether it's a ground issue.

Okay. I feel like the hum is present no matter what. But it’s easier to hear when the Eros is turned on. I’m wondering if it my new apartment. There is an electrical pole like 200 ft away in the parking lot and I can hear something humming outside as well.