Terrible buzz with Helix LT and Bias Rack

[rpurdue75]

Hey guys.  Ho9ping someone can give me some insight on how to fix my problem.  I'm using a Helix LT in 4CM with a bias rack as well as a DSL20CR and Bad Cat Lynx.  I have it hooked up using "humbuster" cables as follows:

Helix Send - Amp input

Helix Return - Amp send

Helix 1/4 Out - Amp return

Guitar into helix "Guitar In"

 

This is absolutely noise free on my DSL and Lynx but when I use the exact same set up with the Bias Rack it introduces a lot of buzzing.  It seems dependant on the amp input as if I leave the helix in the loop and plug straight into the Bias Rack the buzz is gone.  As soon as I add the helix in front of the Bias Rack the hum returns.  I'm not sure why the same set up works flawlessly on the other 2 amps as everything is plugged into the same power conditioner and is even in the same spot pretty much.  I even tried removing the ground from one side of the loop cables and it actually got worse

 

Any ideas?

[rd2rk]

Humbuster Cable Description

 

"When used with the specially designed Humbuster audio outputs of Fractal Audio Systems products, Humbuster cables reduce the hum caused by ground loops. Use a Humbuster Cable whenever possible between the 1/4" outputs of your Axe-Fx II or FX8 and devices like preamps, power amps, guitar amplifiers, etc.

These high quality cables have a nice flexible feel, with endplugs heat-shrinked for maximum durability. The heatshrink is color-coded, so you can easily find the black end to connect to the Humbuster output of your Fractal product and the blue end for your amp or other device."

 

Maybe Helix doesn't like these?

 

have you tried regular shielded cables?

 

Also check the SEND/RETURN settings in GLOBAL SETTINGS>INS/OUTS.

[rpurdue75]

Thanks for your reply!  Well, the same cables are used with my other 2 amps in 4CM with the Helix and no issues.  What specifically should I be looking at in SEND/RETURN settings?

[rd2rk]

17 minutes ago, rpurdue75 said:

Well, the same cables are used with my other 2 amps in 4CM with the Helix and no issues.

 

Means nothing. We're troubleshooting. Try regular shielded cables. What can it hurt?

 

18 minutes ago, rpurdue75 said:

What specifically should I be looking at in SEND/RETURN settings?

 

You have a choice between Instrument and Line. Try them both AFTER you swap out the cables.

[rpurdue75]

19 minutes ago, rd2rk said:

 

Means nothing. We're troubleshooting. Try regular shielded cables. What can it hurt?

 

 

You have a choice between Instrument and Line. Try them both AFTER you swap out the cables.

Thanks!  I will try that too!