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

All bass amplifiers have HPFs. Some are better than others. Some people tried external HPFs and liked them. That's pretty much it IMO.
If there was ever an oversimplification on this topic, this is pretty much it.
 
But, what about way back then when there weren't many Soundmen? Did we just accept that mud was mud or did the amps back then not sound muddy, or did we just live with it?

Before there were soundmen, venues tended to be smaller. I don’t recall shows sounding bad back then. Then woodstock happened which grew into stadium shows. I think that part of the problem was using PA and theater speakers that were not up to the job for huge cavernous venues. It took some time for technology to catch up to the application.
 
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But, what about way back then when there weren't many Soundmen? Did we just accept that mud was mud or did the amps back then not sound muddy, or did we just live with it?
IME, most just lived with it. I heard many an Acoustic 360 full of distortion or Fender Bassman amps always on the edge.

I went another way with JBLs in Kustom and Sunn cabs and their associated amps. After listening to albums with Hofner and Fender Basses (Beatles/Chicago) I played with a pick and did everything I could NOT to have audible distortion of any kind. I would have been able to turn up louder if I would have had an HPF.

Even today, it's a full, clean tone that I look for. I can add distortion if a song calls for it.
 
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But, what about way back then when there weren't many Soundmen? Did we just accept that mud was mud or did the amps back then not sound muddy, or did we just live with it?

Well, for starters, amps weren't as powerful back then as they are now, and today's cabs often produce FAR more lower end than cabs back then, too... Also, there were plenty of times that things really didn't sound all that great - or nearly as good as they could've sounded, anyways...

Or, as an example - an SVT and it's matching cab had it's own sort of high pass/low pass thing built right into it - so, no HPF needed in that case...
 
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Well, for starters, amps weren't as powerful back then as they are now, and today's cabs often produce FAR more lower end than cabs back then, too... Also, there were plenty of times that things really didn't sound all that great - or nearly as good as they could've sounded, anyways...

Or, as an example - an SVT and it's matching cab had it's own sort of high pass/low pass thing built right into it - so, no HPF needed in that case...
I've heard SVTs that have so much bass and stage volume in certain venues that the sound guys couldn't do anything with it and the bass ended up pretty much inaudible and unmixable. An HPF would have fit the situation and cleaned up the tone.
 
Nobody decreed it necessary.

A large part of the evolution on TB could be attributed to fdeck. I think his motivation was likely due to his upright bass confilcting with subwoofers.
Just for accuracy, every bass amp I designed over the last 20 years has incorporated a HPF more sophisticated than a simple first order filter. I have used variable HPFs in console and mic pre designs for a long time as well, which evolved to bass amp applications such as the D-800+ and Rosette products.
 
I've heard SVTs that have so much bass and stage volume in certain venues that the sound guys couldn't do anything with it and the bass ended up pretty much inaudible and unmixable. An HPF would have fit the situation and cleaned up the tone.

I don't think that an HPF would compensate for excessive stage volume, no matter how good it is... What you're describing sounds more like a problem of volume more than frequency control...
 
Just for accuracy, every bass amp I designed over the last 20 years has incorporated a HPF more sophisticated than a simple first order filter. I have used variable HPFs in console and mic pre designs for a long time as well, which evolved to bass amp applications such as the D-800+ and Rosette products.
Perhaps if you had let on about the secret sauce it would be less mystical today. Maybe you did and it went over my head then but no recollection.
 
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IME, most just lived with it. I heard many an Acoustic 360 full of distortion or Fender Bassman amps always on the edge. I went another way with JBLs in Kustom and Sunn cabs and their associated amps. After listening to albums with Hofner and Fender Basses (Beatles/Chicago) I played with a pick and did everything I could NOT to have audible distortion of any kind. I would have been able to turn up louder if I would have had an HPF. Even today, it's a full, clean tone that I look for. I can add distortion if a song calls for it.

I like clean, harmonically rich tone as well.

If you listen to isolated McCartney tracks on youtube, there’s some grit in there. This is common in a lot of songs. This isn’t the same as full out amp distortion that some use. More about weaving in an out of distortion. You don’t hear it in the mix but it adds energy and a sense of urgancy to tracks. Sometimes it’s the amp/speakers, other times it is the recording equipment adding character.
 
So, in the foggy past, studio magic spilled out into the streets and, in time, the engineers cloaked it in glory. This thread's bringing it all home: unbeknown to many, we've shared our space with this magic — and we've done so for quite a long time, as it turns out. Now this magic is well and truly in our hands :)

Thanks again, y'all, especially @Stumbo. This one's been a real buzz ;)
 
For me I first became exposed to one on the Fishman Pro Platinum bass EQ. I read on Bob G's site advice on how to use it and when I used it according to sit advice it helped a lot. We're talking about upright bass playing here. My next preamp was the radial p z pre also had a high pass filter, also used it with great results, likewise for my next pre, the headway. One day I got to thinking hey what if I plug my electric bass into this Gizmo? And viola, the results were great. I think many electric bass players who double on upright had the same experience. Then I read about the F deck one that had a different slope to the filter and minimal controls so I bought that one as well. For me that one was the game changer because of the minimal controls and the unity gain I could use it with every preamp out there successfully. So the high pass filter/ tonehammer became a successful combination for me. But I guess before I had the tone Hammer my only preamps were those three that I had to make use of with both instruments and they had high pass filters in them. so manufacturers had been seeing the need for these things for years with quote-unquote acoustic instruments. Oh and I can't forget my acoustic image amplifier which had one built-in. I had to use both instruments with that thing too and every case I saw that it helped with oth instruments. I don't think I was alone in this situation. So while manufacturers had been putting them in recording equipment and baking them into their amp design for years. I think the pedal format was probably brought to popularity from upright bass players who doubled on electric. A couple guys tried them. Started making postings, and then it went from there. I'm sure you could probably trace the history of it on this website
 
So, in the foggy past, studio magic spilled out into the streets and, in time, the engineers cloaked it in glory. This thread's bringing it all home: unbeknown to many, we've shared our space with this magic — and we've done so for quite a long time, as it turns out. Now this magic is well and truly in our hands :)

Thanks again, y'all, especially @Stumbo. This one's been a real buzz ;)
From TB BG side 2011:
Here's something else to take a look at: HPF-Pre A high pass adjustable filter make by TB'r FDeck.

From TB DB side, 2007:
Review of new pre-amp/high-pass filter
One of those simple little products for which many of us wish is finally available. A little over a year ago, our own fdeck and I had a dialogue about the design of a useful pre-amp/adjustable high-pass filter (pre/HPF). I bench-tested a pre-production version and after a tweak here and there by fdeck, I must say that this is one sweet little circuit from the standpoint of both laboratory measurements and months of use with my DB and rig (RS-2 pickup, EA iamp200, Wizzy 12).
The pre/HPF incorporates a 10M-ohm input and a 12-dB/oct high-pass filter with the corner frequency adjustable (via a knob on the outside) from about 40 Hz to 110 Hz. Only discrete components (transistors) are employed. There are no op-amps in the circuit. The latest production versions also include a phase-reversal switch. All of this is encased in a palm-sized box and the circuit is powered by a 9-volt battery that is connected only when a plug is inserted into the output jack. The battery should provide well over 100 hours of use.
My own measurements showed the frequency response of the pre/HPF to be essentially ruler-flat above the high-pass cutoff at least out to any frequency that could imaginably be relevant to a DB player. That is, the device is not "voiced" in any way. Distortion and noise are acceptably low even when the pre/HPF output is over 1 volt. I'll leave the geek-talk there.
Measurements aside, from my months of actual use of the pre/HPF, I can say that it sounds great. More to the point, it has no "sound." It just does its job. I have never once had an issue with clipping, distortion, or noise of any kind. It effectively solves the "infrasonics problem" about which I so often speak here. I would not want to be without it.
If you're interested, I suggest you send fdeck a PM. In the spirit of full disclosure, I want to explicitly state that I have no financial interest in this device at all. In return for my assistance in testing and measurement, fdeck let me keep the prototype he sent to me.
P.S.-- My understanding is that the price is $50 plus shipping.

From 2006, discussion about designing an hpf including fdeck's comments:
Smart tech people: How complicated is a high pass filter?
I'm convinced that a HP filter is the single most useful bit of EQ I've ever used for DB, and am thrilled that the new Focus 2R has one on both channels, and that they're adjustable to boot. But for all of the amps that don't have one, how complicated are they to make, and what's the smallest an adjustable one could be made that could be used for just about any amp? If there was a really small one that did nothing BUT high pass (especially if it was adjustable), that would be a great tool to carry in the bass bag wherever you might go. What say?
 
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But, what about way back then when there weren't many Soundmen? Did we just accept that mud was mud or did the amps back then not sound muddy, or did we just live with it?
Go back and listen to those "amazing" sounding recordings of our youths. Or for that matter, go back even 10 years ago.
Ignoring volume wars, the sound engineering and application has gotten progressively better overall... Frankly I'm appalled at how bad some of my favorite vintage recordings sound compared to modern standards.
The same thing has happened with cinema quality(plots and acting ignored).
Car racing, computing, etc etc.
The quality we remember is not what it once was!
When I saw that people were using HPF/LPF on bass on pedal boards i felt a "duh" moment and could think of no reason it ad never occurred to me before. I used it consistently when setting up multi-track mixes live or in a studio to free up headroom on the bus. Duh!
So now I wonder how early in the signal chain to put it!
:D
 
When considering the Broughton LPF and HPF, are there any advantages to getting separate pedals (i.e. being able to place them in different spots in your signal chain), or will the single pedal with both filters do the exact same thing?
The filters are functionally the same, but as you said with the separate units you can put them at different places in your signal chain.
The combined H/LPF also has some really nice clean boost available, allegedly.