Setting High Pass/Low Pass Filters

**Navdeep_Singh** · 10-13-2023, 12:04 PM

See attached cab setting. Each one as has high pass low pass filter. What is the philosophy of this feature? What should the settings be for an arch-top guitar, where we want to get the usual warm, clear, pristine, sparking jazz tones? Something to ignore? Something to set? What should be the settings in your opinion? thanks

**omphalopsychos** · 10-13-2023, 12:31 PM

Are you using this for a recording?

Usually speaker dimensions, mic placement, and filters are all decision points for tracking. I wouldn't worry about it if you're just playing. Low e is somehwere around 80 hz fwiw. 20hz is barely audible by most adults.

It's amazing the number of features that people come up with now to get in the way of plugging into an amp and making music.

**Navdeep_Singh** · 10-13-2023, 12:39 PM

Originally Posted by omphalopsychos

Are you using this for a recording?

Usually speaker dimensions, mic placement, and filters are all decision points for tracking. I wouldn't worry about it if you're just playing. Low e is somehwere around 80 hz fwiw. 20hz is barely audible by most adults.

It's amazing the number of features that people come up with now to get in the way of plugging into an amp and making music.

Yes, My main thing is to use this for recording. Greatly simplifies things, overall. A lot less physical gear to maintain, accumulate and buy.

**omphalopsychos** · 10-13-2023, 01:37 PM

Ok then from a recording perspective you don’t need to worry too much for jazz guitar. The low pass filter would help reduce harshness of distortion. The high pass filter will help you cut through a dense mix.

**sm80808** · 10-13-2023, 01:53 PM

Typically the microphone would go to a microphone preamp where you would have access to high and low pass filter options. This would give the producer the ability to filter our specific frequencies to let the instrument/voice to help the signal sit better in the overall mix.

Here are some articles:
Recording Dojo: A High Five for the Low-Pass Filter - Premier Guitar
Recording Dojo: What's a High-Pass Filter & How Should You Use It? - Premier Guitar
Four Ways to Use HP and LP Filters for A Better Mix

**TedBPhx** · 10-13-2023, 03:15 PM

I use a low cut filter to reduce feedback from my flattop. The archtop has never needed that.

**jorgemg1984** · 10-13-2023, 03:25 PM

Navdeep, this is the same reply I gave you on TGP:

With the Helix and an old Guild laminate archtop with a modern PAF I had the hi-cut at around 4k/5k. Above that it was too bright (but I run the tone and the volume of the guitar on full and use a JBL impulse response, that's a very bright speaker). On his most recent video Cordy said he had to go to 2.8k on the Tonemaster Pro, and I believe he uses the same 4k/5k figure on the Helix - it has to do with the slope of the filter. On the Helix the hicut on the cab block has a different slope than any of the other ones (I use the one on the parametric eq), and it's not usable for me. No idea what the slope figures are on the TM Pro.

I don't use the low cut but I use a PAF that has tight bass (rarer than you might think, most have too much bass for an archtop with heavy strings, especially Alnico 2s) precisely to avoid using low cuts. With my current PAF, I can even run a blackface bass knob on 4 or 5 with no boomyness. Unlike hi cuts, I find low cuts can remove too much "precious" frequencies - the bass frequencies affect non-bass frequencies more than treble frequencies affect non-treble frequencies, in my experience. If I used one, I would not go above 100hz.

Also, I would say that besides messing with the hicut/lowcut it's a good idea to have the cab block well set. So, a good speaker, and good mics. I love the R121 SM57 combo, it's a classic for a reason. These days I don't even mess with cab blocks, they make me OCD - I enjoy the York Audio JBL Twin a lot and just use that all the time. Removes the guesswork and the OCD.

Asuming you're using a Fender blackface amp, I also find a 4db/5db boost on the 400hz/500hz area helps bringing some fatness back. It's still scooped but not that scooped. You can do that with a graphic or a parametric.

Hope this helps.

**fep** · 10-13-2023, 04:29 PM

High pass to get rid of low end boominess. If boominess is an issue, start at about 100hz and slide frequency up and down and use your ear.

**bluejaybill** · 10-13-2023, 07:12 PM

Originally Posted by fep

High pass to get rid of low end boominess. If boominess is an issue, start at about 100hz and slide frequency up and down and use your ear.

Yes, particularly when recording it is common to shelf the lows at 100 or less to help keep the guitar out of the way of the bass. I probably wouldn't mess with it on a modeler unless it's a big cabinet with a lot of low end resonance.

I rarely shelf the high end, there's not that much up there on electric guitars but if there is, it is likely fizz, so for that it could be useful.