Helix LT White Noise/Hiss Help!!

[Aged_Cheddar]

OK, so I'm in the final stages of getting setup for this coming springs round of shows...but I have an issue that's plaguing me, and I first thought it was me, but now I question my LT.

 

Friggen white noise/hissing...it's really beginning to wear on me, especially between songs.

 

I'm running the 3.50 patch, so I think I'm up to date as far as I can be.

 

I've checked my outputs, both the XLR & 1/4” hiss, yet the headphone out doesn't.

 

I get the hiss whether I'm plugged into my Mackie Mix8 mixer, or into my recording interface for my PC. (tried the 1/4” and XLR with both)

 

It's not one particular patch, it hisses on every patch, even ones without a high gain amp sims.

 

My volume knob is only set to control my 1/4” outs, the XLR's are obviously @ unity.

 

I've obviously checked to make sure I'm not sending phantom power from the board into the Helix, I've tested the ground lift.

 

I've tried the XLR outputs on both “Mic” and “line” the only difference is line has a louder hiss obviously.

 

A gate is NOT the answer...If I leave my headphones plugged into the mixer, and turn off the Helix, the hiss stops, so I'm definitely not driving the board or headphone amp portion too hard...The hiss is (in my opinion) coming from the Helix itself.

 

I've tried my Shure IEM buds, and 2 sets of headphones, they all had the same noise to varying degrees...The IEM's highlight it the most obvious though.

 

I've tried multiple cables, all with the same result.

 

I've tried multiple basses, both active and passive, so it isn't any one bass.

 

I've even moved my setup to another entirely different room, on a different breaker, to rule out “dirty power”.

 

The noise is basically inaudible while playing, but between songs, there is no getting around the hiss.

 

I LOVE this unit, but I am so close to just tossing in the towel and going back to individual stomps, which I might add were dead silent on my last board.

 

Does anyone have an idea I haven't thought of??

 

This can't actually be normal for a Helix LT can it??

 

Thanks in advance for any help or insights!

[DunedinDragon]

On 12/28/2022 at 8:36 PM, Aged_Cheddar said:

 

 

I've checked my outputs, both the XLR & 1/4” hiss, yet the headphone out doesn't.

 

THIS is the key indicator that you most likely have a signal level gain staging issue within your patches (as determined by the channel volume on your amp model) which is adding noise to your output.  What you're not telling us is where you have your signal gain staged at on the mixer and on any powered speaker outputs.  I have my XLR output that goes to the mixer disengaged from the Helix volume knob and set to Mic level output (which sends a full volume signal to the mixing board).    I control my output levels within my patches primarily through my amp model channel volume (typically set between 4 and 5) and additionally through the output block on my patch such that I get a reasonably clean signal level with the gain on my mixer channel set to about 1/4.  Even then some of the amp models are just noisy and produce a fair amount of hiss based on the modeling of that amp, but most are totally silent.  I no longer go direct from the Helix to my speaker, but when I did I had the 1/4" output set to line level and it was controlled by the Helix volume knob with my powered speaker set to unity level or at noon on the speaker's gain knob.

What helps in this regard is that I have my Helix hooked up through my mixer when I'm dialing in my patches.  That allows me to monitor the signal level on the mixer as I'm dialing in my patches and set the appropriate levels on my amp channel volume or output block to achieve a correctly gain staged signal level as measured on the mixing board.

[codamedia]

My Helix is silent... or at least as silent as anything else I've owned over the years. 

Share a preset.... and/or provide an audio sample of your hiss.  

[Aged_Cheddar]

On 12/29/2022 at 3:27 AM, DunedinDragon said:

THIS is the key indicator that you most likely have a signal level gain staging issue within your patches (as determined by the channel volume on your amp model) which is adding noise to your output.  What you're not telling us is where you have your signal gain staged at on the mixer and on any powered speaker outputs.  I have my XLR output that goes to the mixer disengaged from the Helix volume knob and set to Mic level output (which sends a full volume signal to the mixing board).    I control my output levels within my patches primarily through my amp model channel volume (typically set between 4 and 5) and additionally through the output block on my patch such that I get a reasonably clean signal level with the gain on my mixer channel set to about 1/4.  Even then some of the amp models are just noisy and produce a fair amount of hiss based on the modeling of that amp, but most are totally silent.  I no longer go direct from the Helix to my speaker, but when I did I had the 1/4" output set to line level and it was controlled by the Helix volume knob with my powered speaker set to unity level or at noon on the speaker's gain knob.

What helps in this regard is that I have my Helix hooked up through my mixer when I'm dialing in my patches.  That allows me to monitor the signal level on the mixer as I'm dialing in my patches and set the appropriate levels on my amp channel volume or output block to achieve a correctly gain staged signal level as measured on the mixing board.

 

OK, so admittedly I know nothing about gain staging, I just twist knobs all willy nilly until I find tone magic...Don't judge. :-)

 

Now as far as output setup, I do the exact same as you, I send XLR to the house (set to "mic"), and the volume knob only controls my 1/4" output, as I'll sometimes be using an actual amp, I want to be able to control volume from my Helix.

 

I get what your saying about channel volume...for example I really like the Ampeg SVT-4 amp model, but the drive is OFF THE CHARTS, so I dialed the drive to zero (where I prefer it, I put drive blocks before it), but then the output level drops so much that I had to max the channel volume to make up the difference...but I'll mess with that more this evening after work...However this still doesn't explain the noise on a brand new patch for example, where there is no amps or anything else.

 

I have a question with this----> "I control my output levels within my patches primarily through my amp model channel volume (typically set between 4 and 5) and additionally through the output block on my patch".... As I mentioned above, I understand the channel volume, but is there a separate patch volume? If so I think I've missed it, where is it located? (sorry if that's a noob question).

 

 

Looks like I have some homework this evening.

 

 

[Aged_Cheddar]

On 12/29/2022 at 6:33 AM, codamedia said:

My Helix is silent... or at least as silent as anything else I've owned over the years. 

Share a preset.... and/or provide an audio sample of your hiss.  

 

I'm at work at the moment, once I get home tonight I'll try some of the things posted above, if they don't help, I'll try and post a sound sample.

[PierM]

On 12/29/2022 at 3:36 PM, Aged_Cheddar said:

... and additionally through the output block on my patch".... 

 

 

 

That's not a good approach. You should not use the output block level as this is a boost (post gain), which means pulling hiss from noise floor and squeezing headroom.

[Aged_Cheddar]

On 12/29/2022 at 8:44 AM, PierM said:

 

That's not a good approach. You should not use the output block level as this is a boost (post gain), which means pulling hiss from noise floor and squeezing headroom.

 

I don't do this, I was just inquiring where one would find the patch volume...I'm sure it's there, and I just over looked it.

[PierM]

On 12/29/2022 at 4:13 PM, Aged_Cheddar said:

 

I don't do this, I was just inquiring where one would find the patch volume...I'm sure it's there, and I just over looked it.

 

That's a good starting point

 

 

 

[Aged_Cheddar]

Alright so I gave my entire chain a good shake down...

 

I found a few things, mostly settings.

 

First, I turned on the input gate, and guitar pad, I run passive EMG equipped P-Basses for the most part, which are hum cancelling, but there was some slight noise...I'm not super certain on proper settings, so I left it factory with Threshold @ -48 dB, and Decay @ 100 ms, I changed the "Guitar In-Z" to 1M Ohm, which I understand is suitable for bass guitars...these tweaks cleaned up the signal coming in.

 

Second, I dropped the level 2db on the "Deluxe Comp", seems I was punishing the input of the SVT Sim.

 

Third, I raised the drive on the SVT-4 Pro up to 4.0, but then lowered the channel volume down to 5.0, then I did some tweaking on the graphic in 5 kHz-8kHz bands, along with some subtle tweaks on the high mid frequencies, these subtle tweaks REALLY opened up the amp, without adding any more noise, in fact I cut some out.

 

All of these fixed most of my hissing issues, but it's still a wicked hot signal coming out of the Helix (even with the XLR outs set to Mic), so hot that I now have the channel gain on the board @ -20 dB (this board doesn't have a pad button, just a gain knob), and channel level & main out are @ unity, so I obviously can lower them if I run into any clipping at my monitors.

 

So far I'm cautiously stoked, it really surprised me how a small tweak at the front of the chain, had such cascading effects further down the line.

 

Is my signal dead silent? Nope, but it's about 85% improved and I'm still tweaking, the real test will be rehearsal in a few weeks using the bands gigging IEM rig, if there is noise, that system will certainly find it, but if my patches sound like they do at home, it'll be smooth sailing.

 

Thanks to those that offered some advice! It really helped!

 

[codamedia]

On 12/30/2022 at 9:34 PM, Aged_Cheddar said:

So far I'm cautiously stoked, it really surprised me how a small tweak at the front of the chain, had such cascading effects further down the line.

 

A traditional pedal board plugged into an amp does the exact same thing. Eg: Take a boost at the start of your pedal board and turn it up a notch or two... everything down chain will be affected by that.  On a traditional pedal board players intuitively bend over and make the change, yet surprisingly on a modeler they don't think about doing that. 

 

You're on the right track... give yourself some time to sort it all out, you don't learn gain staging over night. Actually - I'd suggest you never stop learning about gain staging and all the tricks (and gotcha's) that come with it.