Remedies for Low USB Levels or Overdriven Tones

[soundog]

If you use your Helix as an audio interface to record your dry guitar signal via USB 7 and/or 8, you have probably noticed the resulting waveform in your DAW is really wimpy. That can be a pain if you need to do any visual edits, or work with pitch or time-align plug-ins such as Melodyne.

 

On the other hand, if you record your dry signal via an audio interface other than Helix (or normalize the Helix/USB recorded waveform to decent visual levels), you'll overdrive Helix Native's inputs. HXN is really really really picky about input levels, so it's easy to overdrive stuff, especially your amp gain. To make things worse, HXN's input meter is (to be polite) lacking.

 

In short, there's a tradeoff between getting levels you're used to seeing in your DAW vs levels that HXN requires .So....here's what I do:

 

1) I normalize my dry guitar recorded waveform to -18 dbFS. (Use whatever level you are used to, -12, -6, etc). If you record your dry guitar with an audio interface other than Helix USB, you can simply set you level so its not clipping the inputs (no DAW normalizing needed). This step is intended to provide a "healthy" waveform consistent with your other recorded waveforms.

 

2) Uh oh! Now your nice-looking waveform will overdrive HXN's input and your tone will suck! What to do? I place Hornet's TheNormalizer plug-in (cheap, $5) in front of HXN, set the desired level to -24 dBFS,  and play the guitar track  to automatically set the level (or just play the section with peaks). You can use whatever plugin you want, or simply use a meter. You can also use HXN's input meter settings, but I prefer to bring the level down before it hits HXN, and I leave the HXN input level set to 0 dB. The main thing is to make sure the peaks you see in HXN's input don't go above -24. The manual says up to -12 is OK, but my experiments indicate that's too high.

 

3) Set HXN output level as desired for subsequent plug-ins or DAW level setting.

[phil_m]

Most DAWs have a command that lets you increase the waveform without actually affecting the audio. In Reaper, for example, there’s a function called “Increase Peaks View Gain” that will increase the visual amplitude of all the waveforms… It’s really helpful for editing quieter tracks.

[soundog]

Good point. Yeah, Logic has a similar function. If you don't need to do any audio editing in other plug-ins that's good enuf....

 

I prefer having all my recorded tracks at -18 dbFS in case I need to do use the track with other plug-in (or bus) processing, or if I send tracks out. Also, -18 dBFS is the reference level recommended by most pro audio engineers. For me, this level on all my tracks provides the best headroom when mixing or mastering. Helix Native is a bit of a plug-in anomaly, I just want users to to be mindful of the levels you give it. This may be the true for other amp sim plug-ins, I don't know.

 

UPDATE: Just found this interesting article on amp sims and expected input levels. This guy is recommending a -30 dBFS level. In retrospect, I was finding that -26 dBFS was sounding a bit better (and null-tested better) than -24 dBFS for HXN, so I may drop my normalized input level to -30 to be on the safe side. Here's a quote from the article:

 

"Once you find the correct reference level, the [Eleven free] plugin behaves differently. Gain knobs have smoother travel and wider response. The high end of the distortion can be less harsh, a common complaint. So I went looking into other plugins. But finding the answers proved hard. Not owning a UAD box I found the manuals for their guitar system enlightening. They use a lower level, around -30 as well. I discovered the Plugin Alliance releases of the same emulations do too through experimentation. I initially demoed some of them and didn’t like the tone and play. I figured a Dumble or Diezel, amps I hadn’t played analog, should be more responsive and subtle. Once I tried -30 the amps opened up. I suspect the code was a straight port of the UAD version. But Plugin alliance wouldn’t answer my direct questions. At all. It was actually a little disheartening.

 

So the end result of my research was sadly inconclusive. There are many small amp simulation companies doing amazing work and the field has exploded in the last couple years. But try as I might I cannot get straight answers out of many of them. Some have vaguely admitted to a -20 level, such as some Nembrini products, however he’s not as certain as I’d like. Some, like Neural DSP, never answered me at all. Antelope was unable to get that information from the developers of their amp sims I just got informed. However being aware of this reference level discrepancy can be enough to overcome many issues. You now know that it can be a problem and if the plugin you’re trying isn’t quite responding the way you’d expect or like, this may be part of the issue."

[DolurumMafikala]

@soundog I just logged on to make a similar post but will keep things together here. I wish I had seen your post months ago as I've ended up with the same discovery.

 

I was initially disappointed with HXN but persevered and have now found great sounds by turning down the input level. In my case I am not using Helix HW to record, rather I am using a dedicated audio interface. I am applying a -12dB trim on the input level in the plugin itself. I am applying a +3dB trim on the output level slider so the monitoring level is good. Like you, I'm finding that you have to turn down the input to HXN even more than it says in the manual. I find things sound good when the input meter stays in the green. Any yellow and things start to sound harsh.

 

There are a lot of confused posts out there with posters conflating (1) the gain on their audio interface input channel, (2) the right input level to their plugin, (3) any gain/drive/channel volume/volume pedal/boost pedal settings on the models within their plugin and (4) the output level on their plugin. These are all separate and things become clearer when they are treated separately.

 

(1) is about capturing a healthy, not clipped audio signal into your computer. This is what Soundog talks about in (1) above. Any DAW processessing needs this.
 

(2) is about applying the right level of signal for the models in your plugin. I think this is where it can get confusing. It seems that HXN wants a pretty quiet level to sound good. A nice, loud signal into your DAW seems too loud for HXN, so you have to turn it down. Soundog talks about this in (2) above. I'm using the input trim in the HXN plugin itself to achieve the result.

 

Other plugins like Amplitube or Guitar Rig seem to be happier with an input level (2) that is similar to the DAW capture level you set for (1). Maybe some do some internal levelling - we wouldn't know. Some, like Peavey Revalver, have a "Learn" button that listens to the input and turns it up or down as needed for that plugin. Some plugins document their input level needs, some don't.

 

When I say I am applying a -12dB trim in HXN input, I should also point out that I am keeping my signal captured into my DAW pretty cool too - not often peaking over -18dBFS on my DAW meters. I'm using a Focusrite Saffire 6 USB with the Gain at 0, Instrument switch in and Pad switch in to capture the guitar.

 

In summary: If you think Helix Native sounds bad, particularly if it sounds harsh, clipped or unpleasantly-distorted then try turning down the input level trim in the plugin so that the meter does not go into the yellow.

 

I've circled the relevant points in red on the attached screenshot.

 

Hope this helps. @Digital_Igloo @Line6Tony You might consider a sticky in the Helix Native forum along these lines. I worry that people who just try the trial and don't adjust their capture levels would get a bad first impression and just dismiss the product. I know the manual covers levels but it looks like some of us are finding we need to turn down even more than the manual suggests.

 

DM

 

Edited March 13, 2022 by DolurumMafikala
Spelling errors

[soundog]

Very true. Thanks for the post. I wonder if, perhaps, Line 6 assumed everyone would record tracks via Helix USB, so they made those input levels anemic. I'm like you, though —  I record via an audio interface (its my input/output/monitoring "hub" for all audio to and from my DAW). Bottom line, folks, keep those HXN input levels low!