This thread is why I use pass filtering for my DI line. I don’t like giant sub lows, and I don’t like tweeter frequencies. And too many sound techs these days like both.
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Huge difference in tone between post-EQ feed to PA vs amp tone.
- Thread starter caballero59
- Start date
@caballero59 , a pre-EQ DI signal is not going to have massive lows unless you are doing something to hype the lows before your signal gets to your amp. This could involve either cranking the lows on an active bass or using some sort of EQ pedal to boost the lows.
I usually set the tone controls on my (active) bass to the center detent and dial in my stage sound using my amp. During the show I may make some changes to the controls on my bass, but not adding a massive bass boost. The signal going into my amp is relatively neutral and unprocessed.
Actually, I typically plug my, bass into a stand-alone DI, like a Radial J48, and the Thru from the DI is plugged into my amp. With the arrangement my amp does not have any possible impact on the DI signal. Running a pre-DI on your amp should also send a neutral signal to FOH.
If a neutral signal sounds hyped in the PA, it's because the subs are cranked or the audio tech has boosted the lows on your channel of the mixer.
IMHO the solution is for the audio tech to properly set up the PA and/or properly adjust your channel strip.
You need to keep in mind that the sound off the back of the PA is not a good representation of what it sounds like out front. With small subs, the lows wrap around the cab, and essentially radiate equally in all directions. As the frequency goes higher the PA will develop more and more pattern control and shoot most of the sound forward. So it's not unusual for you to hear a bit of backwash off the subs.
The problem can be even worse if the system has several subs lined up side by side. Then the dispersion pattern forms into dipole, and the sound shoots out pretty much equally to the front and back. I.E. this sort of array puts massive amounts of sub-bass on stage.
In order to judge how the bass sounds to the audience, you need to go out front. You can do this with a long chord or wireless.
If the audio tech can't or won't mix the bass properly, IMHO the solution is to hire someone who can and will do the job appropriately.
Trying to control your sound from the stage is not a good strategy, because you can't hear what it sounds like out in the house from the stage. Hire a good audio tech and let him/her do the job they are getting paid for, instead of engaging in covert monkey business that makes their job harder. If you are going to do something to the signal, communicate your plans to the audio tech and work with them to try and get the desired results. Try to avoid engaging in behaviors that will be perceived as passive aggressive BS, because it just leads to the formation of toxic relationships.
I usually set the tone controls on my (active) bass to the center detent and dial in my stage sound using my amp. During the show I may make some changes to the controls on my bass, but not adding a massive bass boost. The signal going into my amp is relatively neutral and unprocessed.
Actually, I typically plug my, bass into a stand-alone DI, like a Radial J48, and the Thru from the DI is plugged into my amp. With the arrangement my amp does not have any possible impact on the DI signal. Running a pre-DI on your amp should also send a neutral signal to FOH.
If a neutral signal sounds hyped in the PA, it's because the subs are cranked or the audio tech has boosted the lows on your channel of the mixer.
IMHO the solution is for the audio tech to properly set up the PA and/or properly adjust your channel strip.
You need to keep in mind that the sound off the back of the PA is not a good representation of what it sounds like out front. With small subs, the lows wrap around the cab, and essentially radiate equally in all directions. As the frequency goes higher the PA will develop more and more pattern control and shoot most of the sound forward. So it's not unusual for you to hear a bit of backwash off the subs.
The problem can be even worse if the system has several subs lined up side by side. Then the dispersion pattern forms into dipole, and the sound shoots out pretty much equally to the front and back. I.E. this sort of array puts massive amounts of sub-bass on stage.
In order to judge how the bass sounds to the audience, you need to go out front. You can do this with a long chord or wireless.
If the audio tech can't or won't mix the bass properly, IMHO the solution is to hire someone who can and will do the job appropriately.
Trying to control your sound from the stage is not a good strategy, because you can't hear what it sounds like out in the house from the stage. Hire a good audio tech and let him/her do the job they are getting paid for, instead of engaging in covert monkey business that makes their job harder. If you are going to do something to the signal, communicate your plans to the audio tech and work with them to try and get the desired results. Try to avoid engaging in behaviors that will be perceived as passive aggressive BS, because it just leads to the formation of toxic relationships.
If you have too much low frequency in the PA you can fix that with the PA. Even crappy mixers now have HPFs. What you need is someone running the mixer who is willing to find out how you think you should sound and then be able use the PA to make that happen.
JazznFunk
Supporting Member
Correct. And the sub is probably going to overpower your rig anyway, along with reproducing frequencies that the cab/combo can't do accurately. Send a pre-EQ signal, and use the cab as a monitor only, so you aren't fighting an overbearing FOH mix too much.
Best luck I have had is no eq di to the board. Then do whatever the sound guy says regarding how my amp is interacting with the rest of it. Usually end up with a bass clock radio but that’s rock n roll!!
it’s my job to play. It’s their job to make it sound awesome. If both are pros, it’ll rock,
it’s my job to play. It’s their job to make it sound awesome. If both are pros, it’ll rock,
MDBass
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- Nov 7, 2012
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If a fixed HPF at 100Hz isn’t doing the trick, a variable HPF will get you what you need.
If you have IO available in a Fractal FM3, you’re all set
MDBass
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- Nov 7, 2012
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Couple ways to solve this issue, but your pa will never sound just like your cabs
1) Send a pre-eq signal and hpf at the board and eq differently there so that it fits in the mix the way you want.
2) Send your post but apply hpf at the board and eq differently there so that it fits in the mix the way you want.
The goal is to send a usable signal to FOH no matter if it is pre/post or a mic'd cab.
Couldn't agree more. It needs processing at FOH no matter what signal is sent.
Which is great advice if you like that "150Hz and up" bass tone from the 80s and 90s. A lot of analog mixers designed for stage HPF at 80Hz or higher, which is pretty aggressive...
My approach is to use a bass cab that actually reproduces bass frequencies[*]. If the engineer rolls off the lows about 2 tics it sounds exactly the same out front as on stage, using the post send.
* -- Yes, they sell those now. It's pretty neat.
- Feb 12, 2006
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- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Some bass amps, especially combos, are fairly heavily voiced by adding bass boost and mid scooping so that it sounds acceptable through the speaker. When this is present on the DI out because it's in post-eq mode (which is also almost always post voicing), this added bass boost and mid scoop will result in exactly the symptoms the OP mentioned because a good PA will reproduce those frequencies that are being boosted (much) differently then the bass player's cabs.
This is why pre-eq DI's are often a better way to go, especially when playing through different PA's and with different sound guys each gig. It helps avoid some of this build-up of bass boost, though if the sound guy is "broken", the challenge will be bigger and maybe not fixable in practice.
A real sound guy will use a HPF as needed and will not create a problem but will work to fit the bass into the mix using the best possible compromises.
This is why pre-eq DI's are often a better way to go, especially when playing through different PA's and with different sound guys each gig. It helps avoid some of this build-up of bass boost, though if the sound guy is "broken", the challenge will be bigger and maybe not fixable in practice.
A real sound guy will use a HPF as needed and will not create a problem but will work to fit the bass into the mix using the best possible compromises.
Actually, it most likely will help.
The DI is sending to much low signal to the PA due to its EQ, either user set or voiced by the amp/combo designer. By sending the signal pre-EQ those lows that have been boosted by the amp EQ will not be sent in the signal to the PA.
I'd trust Andy's knowledge below.... when it comes to amps he's usually right.
MDBass
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If you’d read through the replies before posting in an attempt to correct someone, you’d know that I’m both well aware of how a pre-EQ signal functions as well the fact that it won’t solve the OP’s problem in this particular case.
The OP responded to me directly confirming that sending his DI pre-EQ doesn’t fix the issue he’s having.
A flat/pre-EQ DI signal has a lot of sub-frequency information that won’t be present from a bass cab: the OP simply needs to add a variable HPF to his signal chain.
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- Feb 12, 2006
- 61,047
- 5
- 221,002
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Since you are the only one that has this information, the rest of us were suggesting the MOST COMMON cause of theses symptoms, which I then followed up with the last 2 sentences in my post IF there are additional contributing factors involved. This is far from my first rodeo, as I'm sure you are aware of.
MDBass
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This is another good example of not bothering to read the thread before replying.
The OP has already stated that an HPF set at 100Hz is still giving him too much sub rumble through the FOH for his tone goals.
MDBass
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None of what I said was addressed to you Andy: that’s why you weren’t quoted in my reply.
I’m not sure why you’re under the impression I’m the only one with that information from the OP either.
The response I referred to is on first page and viewable by everyone.
- Feb 12, 2006
- 61,047
- 5
- 221,002
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
If a 100 HPF doesn’t resolve the symptoms, then there is something else very wrong. At 12dB/octave, the power at 50Hz will be less than 1/4 the power in the 100Hz region. That’s a lot of removed energy.
There are three possible causes that I can think of:
1. the HPF is not in fact in the signal path
2. there is a lot of low frequency gain in the amp’s voicing or eq
3. the relative level between the PA’s subs and tops is absurdly bottom heavy.
Taking a pre-eq DI signal only resolves #2, but ime it’s the most common cause of the symptoms. It’s not the only cause.
There are three possible causes that I can think of:
1. the HPF is not in fact in the signal path
2. there is a lot of low frequency gain in the amp’s voicing or eq
3. the relative level between the PA’s subs and tops is absurdly bottom heavy.
Taking a pre-eq DI signal only resolves #2, but ime it’s the most common cause of the symptoms. It’s not the only cause.
I freed up some processing in my FM3 and will now be using input 2 to run the bass into a parametric EQ with blocking filter and followed by a compressor before going to the amp.
Like I wrote earlier, mic-ing the cab at this point may be the easiest solution. The mic is going to send a signal the same as what you are hearing from your amp and not directly from your pre-amp, either pre or post EQ. This is why most guitar players mic their amps. The FoH speakers are more like home hi-fi speakers than your bass amp speakers. They are reproducing ALL the frequencies your amp is sending them whereas your amps speakers are nowhere near as flat in their frequency response. This is why you are hearing such a difference between your amp and FoH tone. What I do is either mic my amp or I split my bass signal to a Broughton HP/LP filter into my DI box. The other side of the split goes to my amp. I set the HP to 60-80 and the LP to 5-8K. This way I'm sending the FOH the filtered signal which is lacking the rumble and clank and sending my amp the unfiltered signal. And, my amp volume and tone controls have no effect on what I send the FOH. A lot (but not all) FoH engineers don't really know what to do with the bass guitar. So, they just turn it up until they hear/feel some rumble and see a good light on the board and don't touch it again. This is why us bass players get so frustrated at big concerts as we struggle to hear what the bass player is actually playing but can't because the Bass Guitar is all RUMBLE in competition with the kick drum and not placed in a pocket ABOVE the kick drum and BELOW everything else.
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Your idea makes perfect sense. Another way to skin this cat that incorporates your same idea is run an an amp model and cab IR on the Fractal before it goes to the PA. Actually, low and high pass filters approximate a cab anyway so an IR wouldn't be technically needed. There was a big thread on the Fractal forum about simulating the AITR experience with filters instead of IR's. I think the take away with my situation is the cab is not reproducing frequencies that the amp direct feed is producing. With enough HPF, I can eliminate the boom from the PA but it requires a higher knee than expected. The 100hz HPF on the mixer I believe has a 12 dB/octave slope which helps but still leaves some boom in the 18" sub. Another thing to consider is our small, square rehearsal space which simply doesn't know what to do with that 18" sub. The experience may be completely different in another room but the sub weighs close to 100 lbs and it would be a two man job to carry it out of that space to experiment. I can carry 100 lb no problem, but NOT with the center of gravity cantilevered out in front of me 2 feet.
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