Helix Talk

[Lele]

Helix's actual (measured) Q range goes from 0.3 to 3, that's why I couldn't notch some very narrow frequencies.
Maybe the Parametric EQ was designer to emulate some pedal? Anyway, the actual Q range is not 0.1 to 10.

I was planning to start using the Helix Parametric eq to make some surgical eq cleaning, but it seems it would be a major mistake if the bandwidth is so large, unlike what it seems from the Helix Q value. I haven't compared the Helix Q factor with my VST plugins. I will try sooner or later...

 

[James Freeman]

I will try sooner or later...

 

[Lele]

Thanks @James Freeman!
I also just tried:
I used the VST plugin "ToneBoosters Parametric Equalizer"; same parameters of your post Q=3 gain= -12dB
versus
Helix Native: "Parametric EQ" block, Q=10, gain= -12dB.

They are EXACTLY THE SAME!
So the Helix real EQ bandwidth with Q=10 is about half octave, instead of 1/7 octave!!!

I haven't tried with my Helix Floor, but I suppose it's the same.
I hope that @Digital Igloo can help us.

 

[Stone]

EQ's are VEry Important no doubts

 

[James Freeman]

For now we can treat the Parametric eq like it is an emulation of a pedal or a console, I don't think it was designed to be a surgical eq like in DAW.

 

[Lele]

For now we can treat the Parametric eq like it is an emulation of a pedal or a console, I don't it was designed to be a surgical eq like in DAW.

But in that case they should not have labelled this block with "parametric eq" name and "q" parameter, because they are false or misleading.
I think that so far I have used the Helix Parametric EQ mainly or even only to cut a little the lows before some gainy amp blocks, so I have never noticed this wrong Q parameter. And now I know I can push the Q value a lot when I use it as an ordinary EQ block.
Kudos to you for finding out this (imho) mistake of Helix Parametric EQ block!

 

[dronerstone]

For now we can treat the Parametric eq like it is an emulation of a pedal or a console, I don't think it was designed to be a surgical eq like in DAW.

I found it easy to recreate the sounds of my Dunlop Q-Zone and Stone Deaf PDF-1 with the HX parametric EQ.

Definitely not a studio-grade "surgical" EQ though, I fully agree about that.

 

[James Freeman]

Don't Line 6 just hate when I do that.
I think they will send me a special virus with the next version of Native to nuke my DAW.

 

[DieSchmalle]

Q = fr / Δf = 800Hz / (950Hz-680Hz) ≈ 3
(values read from @James Freeman 's pic)

Using the "full width at half maximum" definition the Helix's Q-factor value is correct.

It's just a question of what Q-factor definition is used.

 

[SwirlyMaple]

Helix’s “Q” readout is probably just a “notchiness” value ranging from 0 to 10, rather than reporting the true mathematical value of Q.

Not saying that’s a good thing. Just saying that’s probably how it ended up that way.

 

[DieSchmalle]

Helix’s “Q” readout is probably just a “notchiness” value ranging from 0 to 10, rather than reporting the true mathematical value of Q.

Not saying that’s a good thing. Just saying that’s probably how it ended up that way.

No. It's a question of what definition is used when measuring bandwidth: +-3dB or half maximum.

Take the example above:
Q = fr / Δf = 800Hz / (950Hz-680Hz) ≈ 3 (half max definition, here -6dB)
vs
Q = fr / Δf = 800Hz / (850Hz-770Hz) = 10 (-3dB definition)

 

[HotRats]

Helix’s “Q” readout is probably just a “notchiness” value ranging from 0 to 10, rather than reporting the true mathematical value of Q.

Not saying that’s a good thing. Just saying that’s probably how it ended up that way.

I believe you're right.

 

[James Freeman]

Helix’s “Q” readout is probably just a “notchiness” value ranging from 0 to 10, rather than reporting the true mathematical value of Q.
Not saying that’s a good thing. Just saying that’s probably how it ended up that way.

I also think this is the case.
Looking in the manuals of various parametric eq pedals, their Q doesn't go above 4 at the narrowest setting, sometimes even lower.
So our current parametric eq is more like a pedal, similar to the Empress ParaEq.

A more surgical parametric eq is a very good thing to have in a modeler.
Particularly when shaping the sound visually in DAW (Helix Native) using some pink noise and analyzers then saving the perfected sound as a preset.

 

[HotRats]

I also think this is the case.
Looking in the manuals of various parametric eq pedals, their Q doesn't go above 4 at the narrowest setting, sometimes even lower.
So our current parametric eq is more like a pedal, similar to the Empress ParaEq.

A more surgical parametric eq is a very good thing to have in a modeler.
Particularly when shaping the sound visually in DAW (Helix Native) using some pink noise and analyzers then saving the perfected sound as a preset.

Totally agree, given the broad use of a modeller and the Helix ecosystem, a surgical eq would be a nice addition.

 

[yeky83]

No. It's a question of what definition is used when measuring bandwidth: +-3dB or half maximum.

Take the example above:
Q = fr / Δf = 800Hz / (950Hz-680Hz) ≈ 3 (half max definition, here -6dB)
vs
Q = fr / Δf = 800Hz / (850Hz-770Hz) = 10 (-3dB definition)

Edit: Which btw means that both methods deliver the same result for gain =+-6dB.

I don't think so...? FWHM refers to -3 dB of attenuation, no?

Full width at half maximum - Wikipedia

en.wikipedia.org

 

[James Freeman]

Using this calculator: http://www.sengpielaudio.com/calculator-cutoffFrequencies.htm

With center frequency 800Hz and Q=3, I get two -3dB cutoff frequencies at 677Hz and 944Hz.
But when pointing these frequencies in MEqualizer in my DAW they are the FWHM points at -6dB when Gain is at -12dB.
So which one is it, -3dB or FWHM?

But when using a Notch filter which doesn't have a Gain setting, I see the -3dB point at 944Hz from the calculator.

Also when manually finding and calculating the frequencies at -9dB which are the 3dB points above the -12dB dip, I get a Q of 5.5.
800/(877-733) = 5.55

So yeah, Q factor calculation doesn't make sense to me, particularly -3dB vs FWHM.
And Helix's Q of 10 is none of the above, it's just an arbitrary scale number like from 0 to 10.

 

[DieSchmalle]

Using this calculator: http://www.sengpielaudio.com/calculator-cutoffFrequencies.htm

View attachment 9240

With center frequency 800Hz and Q=3, I get two -3dB cutoff frequencies at 677Hz and 944Hz.
But when pointing these frequencies in MEqualizer in my DAW they are the FWHM points at -6dB when Gain is at -12dB.
So which one is it, -3dB or FWHM?

View attachment 9238


But when using a Notch filter which doesn't have a Gain setting, I see the -3dB point at 944Hz from the calculator.

View attachment 9239

Also when manually finding and calculating the frequencies at -9dB which are the 3dB points above the -12dB dip, I get a Q of 5.5.
800/(877-733) = 5.55

View attachment 9241


So yeah, Q factor calculation doesn't make sense to me, particularly -3dB vs FWHM.
And Helix's Q of 10 is none of the above, it's just an arbitrary scale number like from 0 to 10.

I'm not gonna give a lecture here but a hint: dB is tricky and power is not voltage. A passage on the calculator page even kind of explains it.

 

[pipelineaudio]

I'd love to see a 5 band parametric with additional HPF/LPF and where the outside bands could be switched between parametric and shelf

 

[Rewolf]

With resonance?

 

[holoholo]

this is kind of old at this point but man I'm still rocking and loving the Horizon drive. I don't play metal so this isn't a pedal I would've thought to try out IRL but I haven't been able to kick it off my presets. I've read some stuff online, looked at the schematics, took a look at it's frequency response and it seems like just a modified tube screamer with a variable low cut but this one just works for me. I like that I can even use it in front of whatever backline amps and it works in front of super clean amps too as the only source of dirt. The downside is it takes a shit load of DSP and you can't turn the gate completely off (for example, when using it at lower gain settings).