R Speaker Hum

I'm very new to this, so apologies in advance if this should be simple. I did a quick (not exhaustive search ) which helped me rule out some things, but still unable to clean it up.

I have a very noticeable hum coming out of my R speaker when I get the volume to about 80 db - increases dramatically as volume increases. Sounds totally fine otherwise (to my ears).

I am running:
AT-LP-120
Ortofon 2M Blue
Marantz NR1510
Golden Ear 5s
Blue Jean Cables

I have tried switching channels and the issue remains in the R speaker, so I assume it is the speaker itself. But, also wondering what the limitations of placement are? That speaker is more "boxed in" with my turntable not far away from it and a post to the R of the line between speaker and listening position. It is also close(ish) to the outlet running everything (~3-4 feet). I am wondering if anyone has had issues with that as well.

Thoughts?

Much appreciation for any guidance....

 

Do those speakers have powered subwoofers? If so, if the power cord for the R speaker plugged into the same outlet as the rest of your equipment? You could have a ground loop issue. I had this with my speakers which have powered subs onboard.

If that wasn’t the issue..,

When you say switching channels, did you move the speaker cables R to L? Did you check all of your speaker connections to make sure the wires are properly seated/secured?

 

The subwoofer in the speaker isn't powered, although it is paired w a SVS powered subwoofer. I id mean switching R&L, and did check speaker connections.

It dawned on my after that a simple test would be to simply swap R&L speakers to determine if placement in relation to other electronics had much to do with it. ....sometimes it amazes me how long it takes me to think of these things.

 

Ok. I unplugged everything in the outlet next to the speaker and ran it to a new outlet farther away. I also swapped speakers, and the hum remains in the R speaker only. Meaning, the speaker that is on the R, irrespective of which speaker that is when I swap them.

@Drew769 can you explain what the ground loop issue might be? My tt is grounded, but it sounds like you are talking about something else. Everything is currently running through s single outlet/powerstrip. I'm probably being naive, but I thought that would prohibit the loop?

 

It could be acoustic feedback between the speaker and turntable, but that usually manifests itself in both speakers. Maybe you anti-skating is off or the cartridge is mis-aligned?
-Bill

 

I would also check cartridge connections. R could be loose causing a hum.

 

^ will do...had not considered that....thanks @George Blair

 

Checked alignment and that seems fine (acknowledging I don’t have extensive experience, but I do not believe there was user error)
Checked cart connections - all secure.
VTF is 1.8
Anti skate is 1.4

None of the above seems all that unusual (to me)

How close would they need to be for feedback? They are definitely closer than I would like due to room layout - probably 3-4 feet.

 

It depends upon the speaker and the turntable. The bigger the speaker and the lower the frequency it can produce vs how easily the turntable can be vibrated at that frequency and how it handles that resonance. I have had a Rega deck as close to a big speaker (PSB Stratus Gold) and cranked the levels without any issues. Another speaker I had in that spot was a Tannoy D700, both of these speakers would produce prodigious bass output. One turntable I had which was really bad about feedback and footfalls was a Thorens, maybe a 165, and older unit with a light tonearm. A couple of other things that make a turntable susceptible to external vibrations are cartridge / tonearm compatibility, and the dustcover. It's best to keep the lid down when playing a record, or completely removed for the lowest feedback pick-up.
-Bill

 

Try reversing the right and left phono IC cables at the Marantz phono inputs. See if the hum moves to the left channel.

Try a different source.
By chance do you have a CD player, or maybe a DVD player with analog RCA outputs?

Are you using the Marantz NR1510 for 2 channel audio only?

Marantz NR1510 (2019 model) 5.2-channel slimline home theater receiver with Wi-Fi®, Apple® AirPlay® 2, and Amazon Alexa compatibility at Crutchfield
.

 

Thanks for the tips. The concept of vibration of the table makes sense, although I would have suspected it to impact both speakers. I am only using the 2 channels, but I will try a different source and keep tinkering.

thanks much for the advice - enormously appreciated.

 

OK if everything is plugged into the same socket, that checks off on one of the boxes.

Try moving cables around, in particular, separating any power cords from interconnects or speaker cables.

Did you reverse the cables yet and rule out an issue further up in the chain?

 

It doesn't sound too close to me, but move them further temporarily to eliminate one possibility.

 

Thanks for all the guidance....will be working my way slowly from speaker to tt to assess. I'll report back, but it may take me a while since the others in the house are less enthused than I am when I turn it up! Appreciate the list of things to consider....I definitely had not thought of many of these. I'm learning, slowly..........

 

Update: have isolated the problem to the TT.

But, that’s about all I can get to for granularity. Believe antiskate is ok and cart is properly connected and aligned. My TT is so low-end that instead of having it assessed and repaired I would probably simply use it as a con engineer excuse to upgrade.

but......doing a final check-in to see if anyone had any other specific ideas related to the TT.