High Pass Filter (HPF) and Low Pass Filter (LPF) Mega Thread

[Stumbo]

v

IME, a HPF (high pass filter):

1) helps deals with boomy venue and/or stage acoustics (like putting your rig on a stand or a pad, which I also recommend, to disconnect from stage)

2) decreases speaker "floppyness" by reducing mechanical movement, especially in ported cabs. Still, it works for sealed cabs too.

3) Protects speakers from transient spikes.

4) Keeps your amp from working so hard and gives more headroom by cutting unneeded/unnecessary frequencies (below port tuning or speaker ) from being reproduced.

5) Help balance string to string volume.

6) Better stage volume and clarity.

7) Allows your bass amp tone control(s) to boost or cut frequencies that matter. If you add a LPF (low pass filter), depending on your style, you can tame the highs as well.

8) Allows you to control what you send to the FOH mixing board. Why send mud to the FOH? Same for LPF.

9) Helps keep your rig from stepping on the kick drum's slot.

10) Can also be used by guitar and keyboard players to cut their low-end incursions into bass guitar territory.

11) Helps you sit in the mix better because your rig is not reproducing muddy and/or non-hearable lows even if it sounds good on stage

12) Allows your passive or active bass guitar tone controls to be more effective

13) Will help control 5 and 6 string and other down-tuning bass's low frequencies and help your rig go louder and sound clearer and cleaner

14) Controls and protects speakers from effects that produce sub-octave tones. Can also improve sub-octave tracking along with improving the tone of effects that produce too much low and mid-lows, especially distortion effects. Some pedals come with an HPF and some come with an internal splitter that creates both distortion and clean, allowing you to blend both for best effect before outputting to your amp.

15) Also known as a low-cut filter, rumble filter or sub-sonic filter, it could also be called an anti-distortion filter or equalizer. It cuts low frequencies your speakers can't reproduce or reproduce well.

@agedhorse has included an adjustable one in current top-of-line Mesa amps. Gotta mean something!

Some amps come with a built-in, fixed frequency HPF that may or may not be documented. Contact the manufacturer for more info.

FYI, I use the Broughton Audio adjustable, always-on HPF.

 

[Charlie Tuna]

Based on this post it looks like the Bergantino B|amp will soon feature a VLPF in addition to its VHPF:

Quick update for B|AMP owners: We will be soon releasing a new firmware update with a VLPF in it. It will be on the filters screen next to the VHPF.

Bergantino B/Amp at NAMM

 

[dabis]

It might seem so...but you would have to see the results of some of my prior DIYs to understand how wrong you were!


I have...but I need one unit which I can be sure that it will work...

This one is. Works perfectly.

 

[PaulCISSA]

Just got a switchable hpf from Josh Broughton today. Haven’t had a chance to play it yet. The science is hard to argue with and the experiences documented in this thread give me confidence in my decision to add it to my chain.

 

[TheBass]

IME, a HPF (high pass filter) also:

1) helps deals with boomy venue and/or stage acoustics (like putting your rig on a stand, which I also recommend, to disconnect from stage)

2) decreases speaker "floppyness" by reducing mechanical movement

3) Protects speakers from transient spikes

4) Keeps your amp from working so hard and gives more headroom by cutting unneeded frequencies (below port tuning or speaker range).

5) Can help balance string to string volume

6) Better stage volume and clarity

7) Allows your bass tone control to increase or decrease frequencies that matter. If you add an LPF (low pass filter), depending on your style or rig, you can tame your highs as well.

8) Allows you to control what you send to the FOH mixing board. Same for LPF

9) Helps keep your rig from stepping on the kick drum's slot

10) Can also be used by guitar or keyboard players to cut their low-end incursions into bass guitar territory

11) Helps you sit in the mix better because your rig is not reproducing muddy and/or non-hearable lows even if it sounds good on stage

12) Allows your passive or active bass guitar tone controls to be more effective

13) Controls and protects speakers from effects that produce sub-octave tones

Also known as a low-cut filter, rumble filter or sub-sonic filter, it could also be called an anti-distortion filter or equalizer.

@agedhorse has included one in top-of-line Mesa amps. Gotta mean something.

FYI, I use the Broughton Audio adjustable, always-on HPF.

Agree 100%. I am a die-hard 2-band EQ Stingray fan. If you really crank the lows the bass could become pretty nasty to your subwoofers. But with the HPF it's easy to tame the sub bass but keep the low mid/upper bass punch. That's a live saver on stage and your sound man will love you .

 

[beans-on-toast]

Boy, high pass filters seem pretty indispensable. They should call it a million dollar tool. Not something that you’d ever want to loose.

IME, a HPF (high pass filter) also:

1) helps deals with boomy venue and/or stage acoustics (like putting your rig on a stand, which I also recommend, to disconnect from stage)

2) decreases speaker "floppyness" by reducing mechanical movement

3) Protects speakers from transient spikes

4) Keeps your amp from working so hard and gives more headroom by cutting unneeded frequencies (below port tuning or speaker range).

5) Can help balance string to string volume

6) Better stage volume and clarity

7) Allows your bass tone control to increase or decrease frequencies that matter. If you add an LPF (low pass filter), depending on your style or rig, you can tame your highs as well.

8) Allows you to control what you send to the FOH mixing board. Same for LPF

9) Helps keep your rig from stepping on the kick drum's slot

10) Can also be used by guitar or keyboard players to cut their low-end incursions into bass guitar territory

11) Helps you sit in the mix better because your rig is not reproducing muddy and/or non-hearable lows even if it sounds good on stage

12) Allows your passive or active bass guitar tone controls to be more effective

13) Controls and protects speakers from effects that produce sub-octave tones

Also known as a low-cut filter, rumble filter or sub-sonic filter, it could also be called an anti-distortion filter or equalizer.

@agedhorse has included one in top-of-line Mesa amps. Gotta mean something.

FYI, I use the Broughton Audio adjustable, always-on HPF.

 

[PraiseBassing]

Boy, high pass filters seem pretty indispensable. They should call it a million dollar tool. Not something that you’d ever want to loose.

As indispensable as any other equipment we can buy...

 

[Zbysek]

This one is. Works perfectly.

It wouldn't if I did the assembly..

 

[Stumbo]

Just got a switchable hpf from Josh Broughton today. Haven’t had a chance to play it yet. The science is hard to argue with and the experiences documented in this thread give me confidence in my decision to add it to my chain.

Please post on your experiences when you put it into use.

 

[Mark Andrew]

Please post on your experiences when you put it into use.

So a couple of loud practices after adding the HPF to my very small effects board and I'm sold. Setting just below the audible level at 30-35 Hz seems to be getting the best results for me and tightening up the low D nicely. I am most surprised about the effects on the crunch channel. It was not very usable but gives lovely grit with HPF on.... a distortion pedal with HPF on makes for a lot of distorted tweeter highs that I will have to eq out.....but super piece of kit. I think I will keep it permanently on In the loop but on floor now while experimenting.....

 

[Stumbo]

So a couple of loud practices after adding the HPF to my very small effects board and I'm sold. Setting just below the audible level at 30-35 Hz seems to be getting the best results for me and tightening up the low D nicely. I am most surprised about the effects on the crunch channel. It was not very usable but gives lovely grit with HPF on.... a distortion pedal with HPF on makes for a lot of distorted tweeter highs that I will have to eq out.....but super piece of kit. I think I will keep it permanently on In the loop but on floor now while experimenting.....

Cool.

An LPF may be in your future to tame those fizzy highs.

 

[Mark Andrew]

Cool.:thumbs up:

An LPF may be in your future to tame those fizzy highs.

I kinda expected that coming . There only audible with the HPF on . As time progresses the tweeter is getting turned very low and this solves the issue for now. My classic 400 was the amp with the room shaking lows and I'm still trying to find the right amount of mids with this amp it was all low and all bright HPF helps allot with this. But my continued enthusiasm to try other basses and not just a P bass configuration always puts me back to square one eq wise........ Hey ho....

 

[Stumbo]

But my continued enthusiasm to try other basses and not just a P bass configuration always puts me back to square one eq wise........ Hey ho....

Programmable eq. with 4 memories might work for you:
Source Audio EQ REVIEW: bass-pedals.com

 

[K-2]

Hey guys. I thought this might be the best place to get opinions as well to learn something new.
For quite some time I was thinking about adding a HPF/LPF to my rig.
I got down to two options - Broughton HPF/LPF and OmniCabSim (which if I understand correctly - is a HPF/LPF in its essence).
Trying to be brief : My goal is to get rid of low end mud/boominess and as much as I like high end - I dont think I need something like 10 kHz in my signal.
If that matters when giving opinions, my rig is - Peavey Minimega - 2 Ashdown 4x10 - Tech21 DP3x preamp and EHX hotwax. Basses varies - J, PJ and HH.
I believe that both options would give me my desired results, but as I live in Europe and both pedals would come from overseas - I dont have a prestige of trying them out beforehand as well will incur Taxes, etc.
Maybe someone had experience with both units? Please share anything and everything.

Apologies for my English

Cheers guys!

 

[agedhorse]

Programmable eq. with 4 memories?
Source Audio EQ REVIEW: bass-pedals.com

If this truly supports 2.2VRMS signal levels as the manual suggests, it might be an ideal pedal to use within the effects loop of a Subway D-800+ (and any of the Shuttle/Streamliner products) to expand the eq options when needed on a programmable basis) because there is plenty make-up gain in the master section to make this work.

Other amps may have enough latitude in effects loop levels but I do not know for sure.

 

[Stumbo]

Analog methods to reduce stage boominess: Do you use a decoupling pad? (Auralex)

 

[JimmyM]

Analog methods to reduce stage boominess: Do you use a decoupling pad? (Auralex)

Bill Fitzmaurice used to say you could accomplish the same thing by putting a rug in front of your cab.

 

[beans-on-toast]

Bill Fitzmaurice used to say you could accomplish the same thing by putting a rug in front of your cab.

I don’t know if a rug will help deaden the sound.

I used to have one of these. With the girls screaming, you couldn’t hear anything out of your amps anyway.

 

[Craig4003]

Bill Fitzmaurice used to say you could accomplish the same thing by putting a rug in front of your cab.

I took a large shipping box of corrugated cardboard, cut it up, stacked four pieces together, ran duct tape around the edge to hold it together, and put it under my bass amp. The loss of floor-contact boominess was quite obvious to my ears.

 

[JimmyM]

I took a large shipping box of corrugated cardboard, cut it up, stacked four pieces together, ran duct tape around the edge to hold it together, and put it under my bass amp. The loss of floor-contact boominess was quite obvious to my ears.

It beats paying $75!