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

If you had say, a Rumble 200 Combo with a Rumble 15" extension cab. I would think a HPF still be useful for taming booming when necessary but wonder if you would still have to worry about cranking it? Unless, the HPF causes the amp to exceed the ratings for the speakers?

I deleted my reply to think about this, but the hpf helps your speakers becomes 'more efficient' and not increase amp or speaker ratings...I think.

Using the HPF *could* allow you to drive your speakers harder than they were designed for, since you might not hear them farting out, nor have the visual cues of the speaker moving more than is healthy for it.
 
where were these things 20yrs ago? Was this some sort of studio secret?
They date WAY back further than that. They're only a secret here because the typical bass player doesn't know half of what they think they know. Still lots of folks here that think they need a rig flat to the fundamental of the "B" - or even to the "subharmonic" an octave below that :wacky:.
 
...and on the topic of Low Cut Switches, I have another device with this feature. It's the Noble tube preamp/DI. The low cut switch "drops 6dB/octave below 150Hz" according to the one-page instruction sheet. Is this functionally identical to a HPF set to 150Hz? Flipping the switch on makes the low end feel tighter. Leaving the switch off makes the low end more pillow like in feel. I usually have the Noble in front of the PJB Flightcase (into FX return).
Basically, yes. Its just a really shallow/gentle slope. Most of the ones we've been talking about are like 12dB or 24dB/octave slope.
 
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Basically, yes. Its just a really shallow/gentle slope. Most of the ones we've been talking about are like 12dB or 24dB/octave slope.

Thanks for the clarification. I have a question in to PJB as to whether the low cut filter built in to that amp is automatically in force if I bypass its preamp and go straight to the power amp from my Noble pre. Too bad we have to wade through so much uncertainty to know exactly how our equipment functions in different configurations. It's one thing to turn knobs 'till it sounds good. But it's handy to know where to turn them if you're kinda in a hurry.....
 
Using the HPF *could* allow you to drive your speakers harder than they were designed for, since you might not hear them farting out, nor have the visual cues of the speaker moving more than is healthy for it.
IMHO, I would temper that statement just a bit by removing the "than they were designed for" part.
"allow you to drive your speakers harder" but not harder than they were designed for.
Nothing lets you safely drive speakers beyond their design limits.
The HPF will attenuate the lower end part of the audio. The part that you don't hear well anyway. And the part that causes more speaker excursion. If you are keeping the low end in check, the speaker can better do its job with signals above the low end cut-off point.
 
They date WAY back further than that. They're only a secret here because the typical bass player doesn't know half of what they think they know. Still lots of folks here that think they need a rig flat to the fundamental of the "B" - or even to the "subharmonic" an octave below that :wacky:.
If I only know half of what I think I know. Then I only know half of half or 1/4. But since I know that, I really know 1/8. Or 1/16? Or...
Holy crap on a cracker! I hardly know anything, and then only half of that! :thumbsdown:
 
Thanks for the clarification. I have a question in to PJB as to whether the low cut filter built in to that amp is automatically in force if I bypass its preamp and go straight to the power amp from my Noble pre. Too bad we have to wade through so much uncertainty to know exactly how our equipment functions in different configurations. It's one thing to turn knobs 'till it sounds good. But it's handy to know where to turn them if you're kinda in a hurry.....
I'd email PJB and ask.

So everything's ok until the heat on the coil windings heat up then poof?:roflmao:
Basically. I'm no expert though... Not even in the "TB Expert club." I just play the bass and use my experience to inform others as best I can. I'm sure someone will come along shortly to tell me everything I've said is wrong. Lol
 
I'd email PJB and ask.


Basically. I'm no expert though... Not even in the "TB Expert club." I just play the bass and use my experience to inform others as best I can. I'm sure someone will come along shortly to tell me everything I've said is wrong. Lol
Right or wrong it's all educational fun, I do get something out of TB.:thumbsup:
 
They date WAY back further than that. They're only a secret here because the typical bass player doesn't know half of what they think they know. Still lots of folks here that think they need a rig flat to the fundamental of the "B" - or even to the "subharmonic" an octave below that :wacky:.
since fdeck popped up the frequency of 20hz rig capable enquiries has dropped to 1.0e-100 hz.
 
Thanks for the clarification. I have a question in to PJB as to whether the low cut filter built in to that amp is automatically in force if I bypass its preamp and go straight to the power amp from my Noble pre. Too bad we have to wade through so much uncertainty to know exactly how our equipment functions in different configurations. It's one thing to turn knobs 'till it sounds good. But it's handy to know where to turn them if you're kinda in a hurry.....
I think it is very unlikely the HPF would not be in the preamp. Likely, early on in the pre.
 
A quick post - just got my Broughton LOW + HIGH PASS FILTER.

Wow, I mean, wow... It's the little things.

A simple pedal, just cuts off the low end high end to suit you. A Band Pass filter, actually. But in less than a minute I was able to dial in a sound I've been after for years.

Just blocks out lows and highs, essentially cleaning up the low end and high end, making the bass sound more like it was recorded and mastered.

This pedal delivers. Love it. Thank you Josh!
 
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All-
Just to preface this properly. I'm not associated with HPFTech llc in any way shape or form. After extensive research into this product I was able to track an order form in an older thread
Invalid Link Removed

I place an order the week before last (on a wed) and got notification from PayPal on Sunday night that my product had shipped. It arrived on Tuesday afternoon and I've been thoroughly impressed with the product thus far.

Setup as follows
Hybrid Bass (carved top)
Fishman Full Circle
HPF 2M
Ampeg SVT4 PRO
GK 4 x10s

I was able to pull a lot more punch and power out of the cab while maintaining amazing clarity and a pretty close to natural tone.

I play mostly small to medium sized clubs/bars/venues and it's always a nightmare having to fight against a finicky room all night or wind up sounding muddy.

I haven't road tested it at a gig just yet (sat night will be the maiden voyage) but I wanted to post this here to just thank HPFtech for addressing a very niche, very frustrating problem and designing a great product and make it a little easier for anyone else who may be interested in this equipment to find.
 
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