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

I checked the Block Circuit Diagram of Genz Benz Shuttle 3.0 (one of my amps) and (without any technical education) it seems to me that the solution is the same as with D-800+ (the HPF is the first step of the preamp allowing it to be by-passed by the "pre" button). If it is the case, I am glad that I have the option of sending the FOH a signal unaffected by the built-in HPF...

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You are correct.
Options never hurt!
 
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I checked the Block Circuit Diagram of Genz Benz Shuttle 3.0 (one of my amps) and (without any technical education) it seems to me that the solution is the same as with D-800+ (the HPF is the first step of the preamp allowing it to be by-passed by the "pre" button). If it is the case, I am glad that I have the option of sending the FOH a signal unaffected by the built-in HPF...

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what works for [you] doesn't work for those who need to undercut the FOHsubsRusWErSUBS mentality.
 
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Typo sorry. What works for you doesn't work for others fighting stupid sub boost from FOH kids who think rock should sound lIke EDM.

I have never thought about HPF as being the weapon to "fight FOH kids". I am afraid that nothing bass player can do on the stage can be sufficient to prevail over "enemy FOH kids". I rather try to see them as allies and try to help them...in a way which I consider beneficial for the overall sound...
 
Amp inbuilt fixed HPF is only around the range PA has on its own subs or lower. Just a rumble filter.

That can be correct for some built-in HPFs... but not for others. I understand that built-in HPFs might differ amp to amp. Especially micro amps (which are presumed to be feeding small cabinets) can have built-in HPFs set higher than others...like Trace Elliot Elf, for example. But if you are correct, it negates your argument that the built-in HPF can be used to fight "stupid sub boost from FOH kids"
 
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I had a guitar player who would have scoffed at the very idea of adding a HPF to his rig. "But it messes with my tone!" His precious tone... so thumpy and bottom heavy I may as well have not showed up to practice at all most days.

The rest of us all did everything we could to get him to turn down the low end on his amp, but he was downright indignant about it. And this is a lifelong friend of over 30 years that I've literally been playing music with for almost 20.

I would get to practice early just so I could tweak his EQ ever so slightly each day. Just a hair so he wouldn't notice... everything was going fine until I realized I was adjusting the wrong channel all along. :p

I even went so far as to buy a Tubescreamer, famous for it's low-end roll off, and gave it to him as a gift. He hated it because it "sucked out all the beef" from his precious tone. Beef which was messing up our entire mix and causing everyone to have to turn up to be heard. I even contemplated hiding my Broughton in the FX loop of his combo, but couldn't figure out how to power it without him noticing.

Somehow I talked him into buying a Telecaster, which was at least clearer and brighter and less bassy than his humbucker-equipped guitar. But cutting low end at the amp... absolutely out of the question! Turning down the gain and playing cleaner? Even more out of the question!

Oh, and did I mention that he was obsessed with using his neck pickup in all the wrong places? Mud city!

So I would say no, people will not just magically understand. Most people have a very pre-conceived notion of what they think they should sound like, and everyone else, and the mix they rode in on, be damned.

My greatest joy in that band was highpassing the crap out of his guitar tracks when mixing our basement jams. "Oh yeah! Sounds really great! Nice work on the mixing!" :p :)

The best solution would be to switch roles in the band... Let him become the bassman! :)
 
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I typically place the amp's built in HPF early in the signal path. The pre out DI signal is pre everything because presumably on gigs that matter the sound guy will have the necessary tools.

It should be noted that most of the amps I design are intended for the upscale market, they are not intended to "fix stupid".
 
what works for [you] doesn't work for those who need to undercut the FOHsubsRusWErSUBS mentality.

They'll just use triggers and some wonky synth patch anyway, if they're anything like some of my "colleagues."
Yel_wink.gif
 
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I just bought one, I have it on my board but need to run power to it. I connected it briefly, but we run all in-ear for rehearsal and I couldn't hear a difference on or off, and I didn't mess with the output level. I will fool around with it and report back.
The Broughton H/LPF boost seems to makes a clear difference at 40 Hz HPF/max LPF at 0dB when through the cabinet, but doesn't make an audible difference with the in-ear setup (Sennheiser G4 w/Shure SE315 in-ear headphones). This was what I expected, the in-ear system has some kind of HPF built-in, and the benefits of the HPF are seen more in eliminating boominess in the cabinet and providing overhead in the amp.
 
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@40Hz
Yep. Each use case is different. With me it was an issue with an SWR-400 head which is more like a reference amp than your regular instrument amp.

It can go down to ridiculously low frequencies. Well below what most cabs can reproduce.

So it runs hot and sounds muddy pushing useless low frequencies. But if you put a quality HPF in the effects loop so it’s between the preamp and power stage, and cut everything below 40-60Hz depending on your cab, it suddenly runs cooler and sounds a whole lot better. Almost like it’s a completely different amp.

I bought my (Broughton) HPF before the always-on version came out. But mine is always on just the same.

Cool tools.
 
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