Slight channel imbalance [resolved]

[kill_surf_city]

I'm experiencing a slight channel imbalance. With no music playing, regardless of whether the turntable is hooked up as well as the ground that goes from the TT to the preamp, I have a difference of 1.6dB. Making the right channel slightly louder. Is this difference worth fixing? Sometimes I think I can hear it, other times not. I'm a little confused because I went to rip a record to my PC yesterday and I couldn't really tell, but the waveform sorta looks off. I've linked a photo. To me the waveform looks a little off but it's the left channel that looks a bit louder. I just wanna see what everyone's opinion on this is and if I decide to try and fix it, what joints should I focus on first? Also, I do have the Sowter SUTs installed since I have a LOMC. Thanks!

here's the photo:  https://drive.google.com/file/d/1kN_Wc1lmlD1jXM9XSCN_ubEpdk2Bg59T/view?usp=sharing

also here's a link the A side of a record I was ripping: https://drive.google.com/file/d/1z6OYLsny_NDByYTYRGtfKEvgN9TKZIJF/view?usp=sharing

 

[Paul Birkeland]

I put a ruler on my screen to try to look for the imbalance and I wasn't able to see it there.  I think you should start by playing a 60Hz tone into the Eros with a different source and measuring the AC voltage at the output jacks.  This is a little hard with step-ups since the typical sources available like old phones and tablets with 1/8" TRS jacks will tend to put out a little too much signal at lower levels, so you may have to get a bit creative on that.  This is an important step, however, as you'd want to narrow things down to the Eros itself. 

Other tests to do would be to swap the incoming channels and recheck, swap the outgoing cables and recheck, then swap the EF86s and recheck.

 

[kill_surf_city]

I put a ruler on my screen to try to look for the imbalance and I wasn't able to see it there.  I think you should start by playing a 60Hz tone into the Eros with a different source and measuring the AC voltage at the output jacks.  This is a little hard with step-ups since the typical sources available like old phones and tablets with 1/8" TRS jacks will tend to put out a little too much signal at lower levels, so you may have to get a bit creative on that.  This is an important step, however, as you'd want to narrow things down to the Eros itself. 

Other tests to do would be to swap the incoming channels and recheck, swap the outgoing cables and recheck, then swap the EF86s and recheck.

After messing around with the interconnects, I’m pretty sure the problem is the cable that runs from the Eros RCA out to my Scarlett 2i2 1/4” input. The imbalance followed the red/right channel cable. Strangely the imbalance is only present with the turntable connected. When it’s just the Eros connected to my interface the balance is almost perfect.

Edit:

Oh yeah also I played the 60hz tone and the balance was almost perfect. Varied slightly but only within like 0.2dB.

 

[kill_surf_city]

Okay I just tried a different cable. Same as the old one. Right channel coming in a bit louder. But when I plug my phone into the input and play the 60hz tone both channels are equal. Has to be something coming from my turntable I guess then? Maybe it’s too close to my Eros.

 

[Paul Birkeland]

It could indeed be cabling or cartridge issues at the turntable.

 

[kill_surf_city]

I swapped out one of my RCA cables and the problem got better. After further testing I can’t discern any channel imbalance while something is playing. It’s only when there’s no active signal. I can live with that!