Helix LT noise - 1/4" output TS or TRS?

[plunky]

Hi All

 

I`ve been plagued by buzzing noise with my LT into Yamaha DXR12 (FRFR). When Im not playing there is an annoying buzz coming constantly from the DXR12. When I rehearse with the band it gets drowned out, so Ive lived with it for the past couple of rehearsals. But enough is enough, Im not going on like this - Im warning you, I`ll go straight back to my real amp and pedals if this Helix thing isnt working out! I haven`t sold any of my expensive analogue setup yet; Im giving the modelling world a chance first...  

 I tried changing the mains point to other sockets in the room, engaging the ground lift on the LT, buzz definitely still there.

I then moved onto checking my cables by replacing each in turn with spares; nope, I`ve still got that buzz happening.

 

Today I replaced the TS guitar cable which runs from the 1/4" out (L) of my LT into the DXR12 with a gold-plated TRS cable. Boom! No buzz at all. Sorted.

I just took a look at the LT owners manual, which states:

1/4” OUT Use unbalanced 1/4" TS cables to connect to your guitar amp, FRFR
speaker(s), studio monitors, or other playback system. When using a single amp or
speaker, connect only the LEFT/MONO 1/4” jack.    

Well Im now using a balanced TRS cable here and it solved my buzzing problem completely. 

Perhaps this little nugget is of use to someone else out there....

 

cheers

plank

 

 

[qwerty42]

See here: 

 

[Dogaral]

At first when I read qwerty42's reply, which shows only a bit of the content in the paste, it seemed not relevant (inputs).

 

But I clicked it, and found what he was talking about:

 

"

Helix Floor/Rack/LT

Inputs

 

Guitar in:  Auto impedance unbalanced TS, the impedance will be determined by the first block in the signal chain. (This is a setting that can be adjusted in Global Settings)

Aux In: 10k ohm unbalanced TS

Returns: 1Meg unbalanced TS (instrument mode)/10K unbalanced TS (line mode)

 

Outputs

 

L and R Main Out: Impedance-balanced TRS

Sends: Impedance-balanced TRS

Dry (Helix Rack only): Impedance-balanced TRS

"

 

So which is it?  LoL.  The manual says TS and the above quote says TRS for same output I think.  I wanna know too cuz im using a power pa speaker that has trs inputs but can use ts inputs and right now at home I am using just a guitar cord for helix out to pa input.  maybe i too should be using trs?  once i get to real playing with my group again post-covid I really wanna be prepared with correct setup.

[lou-kash]

9 hours ago, plunky said:

there is an annoying buzz coming constantly from the DXR12

 

Just a week ago I was doing a FOH mix in a small club, using two such (possibly the same?) Yamaha speakers as stage monitors. At first I went from a small Yamaha mixing desk via Aux 1/2 Out jacks with simple TS-to-TS cables, and got the buzz. So I changed to TRS-to-XLR which has fixed it. No idea what kind of Aux Outs there are on that mixer though. So I'd say there's rather something with those Yamaha speakers; that they don't like TS cables… :)

[phil_m]

6 hours ago, Dogaral said:

At first when I read qwerty42's reply, which shows only a bit of the content in the paste, it seemed not relevant (inputs).

 

But I clicked it, and found what he was talking about:

 

"

Helix Floor/Rack/LT

Inputs

 

Guitar in:  Auto impedance unbalanced TS, the impedance will be determined by the first block in the signal chain. (This is a setting that can be adjusted in Global Settings)

Aux In: 10k ohm unbalanced TS

Returns: 1Meg unbalanced TS (instrument mode)/10K unbalanced TS (line mode)

 

Outputs

 

L and R Main Out: Impedance-balanced TRS

Sends: Impedance-balanced TRS

Dry (Helix Rack only): Impedance-balanced TRS

"

 

So which is it?  LoL.  The manual says TS and the above quote says TRS for same output I think.  I wanna know too cuz im using a power pa speaker that has trs inputs but can use ts inputs and right now at home I am using just a guitar cord for helix out to pa input.  maybe i too should be using trs?  once i get to real playing with my group again post-covid I really wanna be prepared with correct setup.

All the 1/4” outs on all the Helix and HX devices are TRS impedance balanced.

 

As far as the manual, I know it’s nit picky, but I don’t believe it explicitly says the output is TS. I think it says something like, “connect a TS cable...”. But I understand it’s a bit unclear.

 

The nice thing about impedance balanced outs is that they act like balanced outs when connected to a balanced input (with a balanced cable, of course) and an unbalanced out when connected to an unbalanced input. But unlike a true balanced out, you don’t get the 6dB drop when connecting them to an unbalanced input.

[plunky]

3 hours ago, phil_m said:

As far as the manual, I know it’s nit picky, but I don’t believe it explicitly says the output is TS. I think it says something like, “connect a TS cable...”. But I understand it’s a bit unclear.

 

 

Thanks for all replies, but in my first post above I copy-pasted from the manual and highlighted the extract in red for clarity. That text is not ambiguous, it explicitly says  "Use unbalanced TS... to connect to your...FRFR speaker(s)." No mention of TRS.

2 things are still unclear to me: 

1. Where does that text from qwerty42 come from? It contradicts the manual.

2. What are the "L & R Main Outs" in qwerty42`s text? My LT has 2 x XLR outs and 2 x 1/4" outs. I use the left XLR out to connect to the mixer, and as already explained, I use the left 1/4" out to connect to my Yamaha DXR12, needs a TRS in my case. So which of these are the "L & R Main Outs"?    

 

cheers

[plunky]

ok ok ok forget question 2, it says main outs are TRS, which can`t be XLR, can it? Duh!

I still think the manual needs to be amended to include TRS as a possible output cable for the 1/4 " output.

 

cheers

[phil_m]

8 hours ago, plunky said:

Thanks for all replies, but in my first post above I copy-pasted from the manual and highlighted the extract in red for clarity. That text is not ambiguous, it explicitly says  "Use unbalanced TS... to connect to your...FRFR speaker(s)." No mention of TRS.

2 things are still unclear to me: 

1. Where does that text from qwerty42 come from? It contradicts the manual.

2. What are the "L & R Main Outs" in qwerty42`s text? My LT has 2 x XLR outs and 2 x 1/4" outs. I use the left XLR out to connect to the mixer, and as already explained, I use the left 1/4" out to connect to my Yamaha DXR12, needs a TRS in my case. So which of these are the "L & R Main Outs"?    

 

cheers

The text that qwerty42 quoted is from an article on the KnowledgeBase here. It’s correct. It’s been confirmed multiple times by Line 6 employees over the years. As I mentioned, the manual isn’t really wrong, just ambiguous. Most people would probably use TS cables because that’s what the have around. TRS may be better because you get the common mode noise reduction mentioned in the KnowledgeBase article.