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

Yes, the clean boost is to overdrive the amp. But I roll back the volume control on the bass to play clean. That's where the Dragster comes in. It negates the tone suck from rolling back the volume on the bass as well as my long cable run.
Assuming that you are happy how that all works I think your best bet is putting the HPF in the amp's own fx loop. You might find you need more boost if power tube distortion is part of your equation.
 
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...Just gonna jump in here because I can.

I assume the clean boost is to drive the tube front in the PF50T.

I don't understand the dragster either, or the placement of the limiter. I mean, you do you, bass brother! Of it sounds good then it *is* good. It's just that to me, your rig is arranged in a way that is very different to the way I'd arrange it if I had your pedals... Why use the dragster? I'm pretty sure your pedals are true bypass. Also, why did you choose to put the limiter right after your bass, instead of after the boost? And are you running two Ampeg PF-50Ts? Inquiring minds need to know!

Yea, two heads. True Bypass or not isn't an issue because they're always on.

The boost isn't here yet. I may switch them around..we'll see.

See my post above this one on the Dragster.
 
Assuming that you are happy how that all works I think your best bet is putting the HPF in the amp's own fx loop. You might find you need more boost if power tube distortion is part of your equation.

No loop on the Ampeg model I use, so it will have to go on the board somewhere.

I still need to order the Boost, but I may get the HPF first. As you say, I may wind up not needing a limiter.
If that's the case I can use the Keeley as a clean boost.

The heads are only 50 watts each and both are powering two 250 ( continuous ) watt cabs.
 
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Very interesting. I always noticed that the DI signal through the PA tends to sound much brighter than what I am getting through my speaker (I always have the tweeter dialed off). If this is something I can combat with the LPF, I might go for the combo pedal (HPF & LPF) after all.
That's exactly what an LPF can do for you.
 
I just got a Broughton high pass filter and realized i keep the amp volume so low in my room that it really was an unnecessary purchase. The amp at lower volumes sounds better with the pedal off. I will hold on to it in hopes that one day I get to play at higher volumes in a bigger place.

What about recording? It's not just for stage, you know ;-)
 
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SWR SM-400 with HPF.
SWR SM-400 with HPF.


I’ve always got a Broughton HPF patched into the effects loop. Picked up that tip off an SWR forum right about the time I was ready to toss the head. Made all the difference.

I’ve got everything below about 60 Hz dialed out now. And it’s a whole new beast with one of those.


Jim C said: ↑
I've watched 2 other bass player blow up a cab with this head; one of the cabs was mine. Seems like a labratory amp and not suited for music IMO.

The problem there was when they were designing that amp 5-strings were just coming out. And if low was good, lower should be better. Or so they thought.

So they designed them so their frequency response could go down to some ridiculously low number like 5Hz forgetting there wasn’t a cab on the planet that could reproduce those frequencies. So distortion and overheating was the rule.

Adding a HPF is the fix. With a HPF the amp runs much cooler and the sound gets pristine. Bye-bye fried cabs too.

But yeah. They do kinda feel like somebody crossed a reference amp with a science faire project at times. The aural enhancer does nothing IMO but add more mud. And the compressor is equally useless. Most SM-400 owners soon learn to turn them all the way down and then forget they’re there.
 
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Having trouble getting a good drive tone ampless


The turning point in my journey was getting a Tech 21 Q/Strip as my DI, which has HPF/LPF settings. HPF/LPF has been a bit of a revelation for me.

I have an ampless/DI setup that runs into a Clarett 2Pre with a thunderbolt connection to an Apple MacBook. I have cheap and expensive pairs of monitors and headphones. Pretty happy with that sort of setup.
 
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