HPF before or after Octave?

[darwin-bass]

In my case it is the Broughton RFE and the Boss OC-5. Playing 4-string P, J, MM basses. No stage amp. DI to FoH with good subwoofers.

Would you run the HPF before the octave pedal or after it?

 

[ahbass2500]

RFE goes at the end for me. Never needed to run an HPF before Octave over several octave pedals (including the RC5). Putting it at the end cleans up any excessive low before hitting whatever output you use (amp, FOH, recording interface).

 

[silky smoove]

Always after for me.

 

[gregmon79]

After for me as well.

 

[mouthmw]

After pretty much everything for me (except delay and DI).

 

[sloppy_phil]

Probably will ultimately depend on how one uses their octave pedal, but for me it's big dubby and/or synthy low end, so HPF totally goes after to help keep the ultra-deep stuff in check.

 

[Barghest]

Always goes last in the chain, right before my DI's for me. The kind of low end you're filtering out with HPF's isn't useful for much except turning the mix to mud and making your amp work harder.

 

[micguy]

The purpose of a high pass filter is to keep the really low frequency stuff from killing your speakers. If you put an octaver after a high pass, you create more low frequency stuff an octave lower - that completely defeats the point of having a high pass filter. The high pass goes after the octaver. There are few absolutes in pedal order, but this is one.

 

[darev]

I always felt that if I am using a device to limit sub and infra sonics to protect my amp/speakers then it should be placed closest to said amp/speakers. Anything else between them is potentially introducing more sub/infrasonics.

 

[Gorilla Monsoon]

^^^^ This^^^^

 

[HolmeBass]

My HPF is in my amp, so it is after my octaver. Seems like this is the consensus, and it makes sense.

 

[Wasnex]

There are few absolutes in pedal order, but this is one.

IMHO, no it's not an absolute in this instance.

The OP is not using an amp. So in this case, there is potential benefit to running the HPF before the octave, as long as it does not cause tracking problems.

I would expect running the HPF before the octave to improve clarity. Basically the roll off of the HPF scoops out the subharmonic garbage that is unrelated to pitch. So there is less sub-bass noise competing with, and masking the synthesized octave. I wouldn't be surprised if a properly adjusted HPF could enhance the tracking of some octaves.

Running the HPF before the octave allows the audio tech to dial in a second HPF for the system and house mix as he/she sees fit. Assuming a quality digital mixing console, it probably has a variable HPF on each channel.

If possible, get with the audio tech and do some experiments to see what works best with the particular gear you are using.

 

[micguy]

If possible, get with the audio tech and do some experiments to see what works best with the particular gear you are using.

I'd dispute the "if possible" part of that statement. I don't kick on an octaver ever without talking about it with FOH first. They should know that you're going to do that, and have a chance to set up a hpf on the desk to protect their PA. An octave below the E on a 4 string is 20 Hz. An octave below the low B on a 5 or 6 string is 15.5 Hz. The big touring/installed subs go down to about 30Hz in most cases - you should never be putting anything lower than that out of your pedalboard.

Anyway, back to the original question...

If there is ONE high pass filter in the chain, it goes after the octaver. Another way of saying this is if you have an octaver there should always be a high pass filter after it, no matter if it's an amp or a PA you're feeding. Still a very solid rule, which I wouldn't violate. But, yes....

If there are TWO high pass filters (one in the desk or after the octaver on the pedalboard), then adding a second one before the octaver is fine. Yes, it might help tracking. Not blowing up the PA should be job one, though, which is why if you have one, it goes after the octaver.

 

[Wasnex]

I'd dispute the "if possible" part of that statement. I don't kick on an octaver ever without talking about it with FOH first.

As an audio tech, I approve. I suspect a lot of bassist wouldn't give it a second thought.

 

[Mastiff_5]

If I am trying to throttle the low end coming into a particular pedal, then in front of that effect pedal - otherwise, I’m trying to reduce the doubled or modulated low freq’s I don’t necessarily have control over, so, as most have said here: at the end.
Just understand, your filter is a tool. Use it as such. It isn’t magic, it is exactly what you intend it to be.

 

[Gorilla Monsoon]

Ive fooled around with placing a HPF before and after an octave. Both made sense under ideal conditions, i.e. in my head, on paper, whatever. I wanted juuust a little octave, clean as i could get it, i thought tracking could possibly be improved by cutting below 80hz or so. In the end, after a fair amount of experimentation with a couple of octaves, i settled on this- it is a JohnK build using a Broughton HP/LP filter with a Broughton Subsonic. I found the addition of a HPF to be helpful. The HP/LP is internally daisy-chained after the Octave. He does some very nice work. Of course this would not be possible without the expertise that Mr Broughton brings to this endeavor. A novel approach, i have zero empirical evidence to add to the discussion, just what sounded good to me. I had to add the square- without it, the lighting makes it look all wonky.

 

[darwin-bass]

As an audio tech, I approve. I suspect a lot of bassist wouldn't give it a second thought.

I have certainly kicked on a octave without telling the tech but I've always had a HPF set to maybe 50 Hz after the octave. So ... ?

 

[RobertAuCoin]

Great thread, great information. Thank you.

Now, should I put HP/LP after OD/fuzz, or before?

 

[74hc]

I guess for me, after, because I let the sound guy deal with HPF. I haven't seen a digital console without HPF settings per channel.

 

[ImTheOnlyOne]

The thing about the Broughton RFE not mentioned (I think) so far is it's mids controls.
I found a slight boost there can really help tracking.

Consider a limiter following an octave or synth effect.