Thank you for correcting my misinformation, I thought the device hat both an HPF and an LPF.
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Why basses don't come with a HP filter in the electronics?
- Thread starter Lorenzop
- Start date
Thank you for correcting my misinformation, I thought the device hat both an HPF and an LPF.
Well it does, in fact have a HPF. It's just that the HPF lowest frequency is 1K. It's for upper midrange/lower treble shaping.
No sir, sorry.
I assure you, a high pass filter control, a low pass filter control and a parametric filter control (short for your frequency-swept tone control) are indeed three different things. Perhaps I'm speaking out of turn, or we are discussing two different things, but my response was to the statement by someone that "the lowest frequency their high-pass filter would go is 1000hZ". That is plainly describing a low-pass filter. Regardless of what device it's used it (bass, guitar, stereo, mixing console, etc)
I'm sorry --you're both wrong...
It is by definition a High-Pass Filter(or maybe it's better described as a kind of Band Pass filter? ) , since it does not ever remove the highest frequencies(but it can boost them). But the fact is that the highest frequencies always pass no matter how it's set. In addition to those very high frequencies the filter will allow lower and lower frequencies into the signal as you open it but only down to around 1K. So the unit has two filters. One works from the middle(up to 3K) down and the other from the middle(1K)and up. But neither will remove the lowest bass OR the highest treble. It's a bit odd but it works.
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Try these filter circuits from a Scottish bass builder. [Invalid or Expired Link Removed]
He has low and high pass filters available.
I have two sets in one of my basses. High and low pass on neck pickup and high and low pass on bridge. The sound shaping possibilities are immense. I have no idea what frequency is at the lower end of the high pass but only found it useful to give me some attack and definition when the low pass filter is closed down so only the very low sub bass range is being used. Unless you are doing lots of soloing or melodic playing in the upper register of the bass a high pass is difficult to use effectively. For bass what works well for me are low pass filters. Alembic use low pass filters and with a Range of 350hz to 6khz anything above that is attenuated at 12db/octave.
Jazzyvee
He has low and high pass filters available.
I have two sets in one of my basses. High and low pass on neck pickup and high and low pass on bridge. The sound shaping possibilities are immense. I have no idea what frequency is at the lower end of the high pass but only found it useful to give me some attack and definition when the low pass filter is closed down so only the very low sub bass range is being used. Unless you are doing lots of soloing or melodic playing in the upper register of the bass a high pass is difficult to use effectively. For bass what works well for me are low pass filters. Alembic use low pass filters and with a Range of 350hz to 6khz anything above that is attenuated at 12db/octave.
Jazzyvee
Passinwind
I know nothing.
- Dec 3, 2003
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The lowest corner frequency is 1KHz and it is a high pass. I stand by my description of its effective function too, but it's cool by me if anyone has a different spin on it semantically. I've actually built and used plenty of these circuits, but more often in synthesizers.
From that link:
TREBLE FILTER STACK
The treble stack is there to address the top end of the spectrum as the filters cut off below the very highest frequencies you can get from roundwound strings. Here we're talking about the high end 'sizzle'. The frequency control also goes well down into the upper midrange around 1kHz. This is another filter type, a HIGH PASS FILTER in the treble signal path. This sets the frequency above which the treble spectrum is allowed to pass through. The upper knob controls the gain (boost) applied to the treble frequency while the lower ring controls the frequencies which are allowed through. Turning the frequency ACW allows more of the lower treble spectrum. Setting more CW allows only the higher frequencies of the treble spectrum to pass.
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Whatever, fellas...
None of those descriptions mean a thing in the pro audio world where an audio engineer needs to understand the difference in low-pass, high-pass, and parametric EQ. I have 22 years of audio mixing (jazz, R&B, choirs, orchestras, and some rock and roll and country when I had to). I understand that this ain't pro audio, and it's just as relevant.
Actually, I've looked at several bass amps' EQ controls and thought "well, it ain't a Midas Heritage or a Yamaha PM5D, what the heck do those labels mean?". At least, I figured out the EQ controls of my EBS Fafner and I'm well-aquainted with the Hartke 3500 and Ampeg SVT.
I retract my involvement in the discussion. If you understand whatever this is and can get through your gig, more power to you.
None of those descriptions mean a thing in the pro audio world where an audio engineer needs to understand the difference in low-pass, high-pass, and parametric EQ. I have 22 years of audio mixing (jazz, R&B, choirs, orchestras, and some rock and roll and country when I had to). I understand that this ain't pro audio, and it's just as relevant.
Actually, I've looked at several bass amps' EQ controls and thought "well, it ain't a Midas Heritage or a Yamaha PM5D, what the heck do those labels mean?". At least, I figured out the EQ controls of my EBS Fafner and I'm well-aquainted with the Hartke 3500 and Ampeg SVT.
I retract my involvement in the discussion. If you understand whatever this is and can get through your gig, more power to you.
Passinwind
I know nothing.
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I understand your frustration, I've been mixing professionally for 40+ years. Link Removed
Passwind, (topic swerve alert), since you mentioned it, too, do you still mix? I got absolutely sick of it (well, the 22 hour days, clueless musicians and heartless promoters and event managers pretty much did me in). I still work for the production company, but I'm an "operations and logistics manager", getting gear in and out of trucks, getting repairs down, booking engineers, stagehands, and truck drivers. All I'll mix now is twice at church and the MS Symphony Orchestra, which is kinda like a bad marriage that I can't quite get out of, ....
.
I have MUCH more time to play now. And MUCH happier!
.I have MUCH more time to play now. And MUCH happier!
Passinwind
I know nothing.
- Dec 3, 2003
- 23,063
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- Disclosures
- Designer/Toaster Tech @ Passinwind Electronics
Passwind, (topic swerve alert), since you mentioned it, too, do you still mix? I got absolutely sick of it (well, the 22 hour days, clueless musicians and heartless promoters and event managers pretty much did me in). I still work for the production company, but I'm an "operations and logistics manager", getting gear in and out of trucks, getting repairs down, booking engineers, stagehands, and truck drivers. All I'll mix now is twice at church and the MS Symphony Orchestra, which is kinda like a bad marriage that I can't quite get out of, ....
I have MUCH more time to play now. And MUCH happier!
Geri: nope, I retired about two years ago, from what was probably the best local club gig anywhere in this area, 5 minutes from my house. My main thing was always bench tech'ing, then field service and installs, and somehow I got roped into live production way back when I was 20, but usually at a pretty casual level. I worked some big barn shows occasionally, but never as A1 or A2. A decade ago I started concentrating again on playing, winery circuit old school jazz mostly. Retired from that a couple of years back too, but I still play out fairly often and am on my way out the door to an open mike at this very moment.
I think I remember seeing you on the LAB and maybe back on USENET too?
best,
Charlie
I missed Usenet, but I hit the LAB a couple of years after Dave Stevens moved it to the internet in his house. Yeah, I cause a lot of trouble there, too. Good to see you around. Take care,
And THAT'S because a device fitting such a description wouldn't ever be used in pro audio......
.
So anyway, Lorenzop if you are still around, as I mentioned the various Bass VI models frequently have bass cut filters since the 1960's Fender had one. The typical Fender implementation has a nice variable cutoff effect if used judiciously but it kills the signal almost entirely if you turn it all the way down. I've been noodling around with a circuit simulator to see what might be done to prevent that from happening in the heat of the moment and you might be interested in the document attached below. I just finished putting it in my Squier VI and it works pretty well. It is very easy to put it into that model since it already has the HPF and the switch that controls it has an extra set of contacts you can use to implement it. You could put it in any bass if you wanted to however. The document is a work in progress and I have not put the pictures I took tonight into it yet but they won't help all that much if you don't have a Squier VI.
The ACG bass preamp is a a filter-based circuit that's designed to work as an on-board EQ for a bass, so it's a specialized and unusual thing. It's got both a LPF and a HPF with a whole lot of overlap in the cutoff frequencies (along with an "overshoot peak" control that is absolutely like nothing you'd see in a typical LPF or HPF).
It is NOT anything like what an audio engineer would expect in a LPF or HPF. It's not designed as a problem solving tool - not intended to just reduce rumble, etc. - so the cutoff frequencies available are way out of the range that an audio engineer would expect to see.
And so it's really not relevant to the original topic in this thread. I can see where the poster who suggested it might have seen "bass guitar - high pass filter" and thought it was what Lorenzop was looking for, but it's not.
Okay, so explain to the audience of what utility might a HPF be on a bass guitar? I can see the use on a sound board or even on an amp, but on a bass? I just don't see why I'd want / need that.
I think that it is something that only a (small?) minority will have any use for. Evidently they can be useful for recording but if the above "discussion" teaches us anything it is that the studio staff will have exceedingly strong opinions on what a proper HPF is and as a result they already have the filters they want to use and your bass needn't have one of its own. If it has an HPF the HPF it has sucks! I don't think that these filters do anything useful on a normal four or five string bass. The Squier/Fender VI basses have them but they start on the bass E and go up midway through normal guitar territory. The people that play them may want them to sound more like guitars on occasion and an HPF is good for that. Now maybe a sixer or and uptuned fiver and seven plus string basses go high enough to benefit from an HPF for the same reason. But the bread and butter four and five string basses on TB probably don't need them.
But I am an engineer, I earn a living giving the customer what he wants. I try to help him make sensible choices but at the end of the day I give him what he wants.
Why not just get any active preamp that has boost/cut bass (which would be most of them) and cut some bass? Pope preamps even give you a choice of frequencies at the bass end - all bands actually.
A high pass filter, set at a somewhat low cutoff frequency (~30Hz) and placed at the very front of your signal chain would remove a lot of low end rumble. This content often has pretty high amplitude, but due to the low frequency is nearly inaudible anyway. It's basically a pretty tall but - long - wave. Even though you can't hear it very well, your electronics can see it just fine; that tall soundwave coming through eats up headroom just like any higher frequency wave. So you're basically using up a lot of headroom throughout your signal chain to process and amplify audio content that is not useful in most situations. The further up the signal chain you remove it, the more you give the elements in the chain more breathing room - if you remove it right at the bass itself, your effects pedals, your preamp, your power amp, and your speakers are all relieved of dealing with it.
The really low frequency stuff in a bass signal is what usually sends things into clipping, so keeping these frequencies tightly managed will give you louder, cleaner, more defined sound while allowing you to need less wattage and fewer speakers (or allowing you to go that much louder
).
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Passinwind
I know nothing.
- Dec 3, 2003
- 23,063
- 45,972
- Disclosures
- Designer/Toaster Tech @ Passinwind Electronics
The typical bass control's slope will be much shallower than a well implemented HPF and it will hack midbass and maybe even midrange along with the subsonics.
Edit: I worked up a couple of models of one of my DIY circuits; top graph is bass tone control cut to 3/10, bass control nominal peaking frequency = ~35 Hz (peaking and cut are not quite symmetrical in this case, but you get the idea). Second one shows high pass filter set for -3dB point @ 35Hz. I am using a variable 2nd order + fixed 2nd order HPF scheme, with a standard fixed 4th order one the slope would be even steeper and the rolloff at 40Hz even less.
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