Correct way to connect Amp to sound system using DI box? Amp only had Speaker out. No line out, preamp out, etc. I used amp the night before. No problem. While playing next day w/DI box sound people used the sound was very boomie, especially when I used the E string. Turned Bass almost off on amp to no avail. Years ago I had similar experience with another amp. Maybe they did connect the box correctly or maybe using the DI box is not a good idea.
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Connect Amp Using DI
- Thread starter borgward
- Start date
<<edited>>
i re-read your post.
so going from the bass through the DI to the amp and splitting the signal off before the amp to the sound board? or are you connecting the speaker out to the DI?
still, shouldn't be boomy in the room if they know how to EQ a bass
the signal they are getting is clean, no color from the amp (unless you are using the speaker out connection). should be relatively easy to get a good sound unless the room is acoustically terrible (metal walls/ceiling, hard surfaces, not many people in the room)
what kind of DI box is it?
kgb
i re-read your post.
so going from the bass through the DI to the amp and splitting the signal off before the amp to the sound board? or are you connecting the speaker out to the DI?
still, shouldn't be boomy in the room if they know how to EQ a bass
the signal they are getting is clean, no color from the amp (unless you are using the speaker out connection). should be relatively easy to get a good sound unless the room is acoustically terrible (metal walls/ceiling, hard surfaces, not many people in the room)
what kind of DI box is it?
kgb
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No, their signal shouldn't -- and wouldn't -- be going into your amp. Your 'boom' problem would HAVE to be local to your instrument, your amp and/or the speaker cab. Was this your usual rig, adjusted the way you always set it? Were you attempting to boost the bass or lower mid-range in the amp's EQ section? Did you try to do any EQ adjustments on the amp to compensate for the boom? [Edit: Sorry, I re-read the OP and see that he did roll off the LF.]
Something that CAN happen with passive basses and low-end passive DI boxes is the box can load down the output of the bass with an impedance that is too low. This can cause an audible high frequency rolloff, which could create the perception of there being more low end, I guess. The test is to bypass the DI box and compare the two signals at the amp.
Before you deal with sound technicians, you should make sure you understand how a DI box works. First of all, your bass plugs directly into the input of the DI box. If you are using an effects chain, then final output of the effects should plug into the input of the DI box instead. The DI box transforms your instrument level signal to a balanced XLR output for the sound board. There will also be a parallel 1/4” output on the DI box, so you can connect it to your amp with a standard guitar cable.
So your amp receivesthe signal from the DI box. The amp is not feeding a signal to the DI box.
To summarize: bass > effects > DI > soundboard via the XLR, and your amp via the 1/4” output.
If you know this, you will be able to plug in the DI box yourself. All you will need is an extra guitar cable to go from the DI box to the amp.
So your amp receivesthe signal from the DI box. The amp is not feeding a signal to the DI box.
To summarize: bass > effects > DI > soundboard via the XLR, and your amp via the 1/4” output.
If you know this, you will be able to plug in the DI box yourself. All you will need is an extra guitar cable to go from the DI box to the amp.
Bass is passive. Bill Lawrence Humbuckers. Don't know any thing about quality of the DI box. Probably not top of the line. I think next time I will opt out of their DI box. Both places were outdoors. Same Bass, same amp (tube). Started with same settings on instrument and amp. Who makes hi quality DI box? To reiterate, Instrument plugs into DI input. One output goes to amp input. Other output goes to soundboard. Did not notice if other output was XLR or not.
There are many quality pre-amp/DI boxes, I picked up a SushiBoxFX Neptunium, which you can hear in a demo here:
Nathan had stopped production on these but brought back a limited run due to customer demands. Those will also sell out at some point in the not-so-distant future....
Was this the same stage on two different nights, or two different stages/two different venues?
There is one place we play where the stage itself (hollow underneath) is causing obnoxious boominess. Getting the amp up onto an amp stand solves the problem.
Just wondering if the DI had nothing to do with it.
There is one place we play where the stage itself (hollow underneath) is causing obnoxious boominess. Getting the amp up onto an amp stand solves the problem.
Just wondering if the DI had nothing to do with it.
Audio tech's generally prefer for the bass DI to be placed between the instrument and amp input. The reason is this gives them an unprocessed signal that does not change as you adjust your amp. It tends to be easier to massage into shape and allows you to have more freedom to adjust your amp to suit your needs on stage.
Some amps have a built-in DI. Many internal DIs have a pre/post switch (which relates to Pre EQ or Post EQ). Using the pre setting gives the audio tech a signal that is most like using DI between the instrument and amp. However the DI signal may be generated before or after the amp's input gain control. Post EQ means any change you apply to input gain or EQ will affect the DI signal. It can be very frustrating as an audio tech to finally get the bass right in the mix, only for the bass player to change amp settings and mess it all up. There is also variation in where the post signal is taken. I may be before or after the master, effects loop, etc.
Note: Many amps provide a block diagram that shows exactly where the DI signals come from.
A final option would be to run a speaker level DI. This requires a DI that is designed to handle the higher voltage. Consult the DI's manual. This can be useful for tube amps as it allows you to capture any distortion or compression created in the output section. IMHO it is not generally useful for solid state amps. Also a speaker level DI will not include the filtering and tone shaping provided by your speaker. So it won't capture exactly the sound you hear on stage.
WARNING: You can't safely run a speaker level DI off a bridged amp. This includes pretty much all Class D amps.
Some amps have a built-in DI. Many internal DIs have a pre/post switch (which relates to Pre EQ or Post EQ). Using the pre setting gives the audio tech a signal that is most like using DI between the instrument and amp. However the DI signal may be generated before or after the amp's input gain control. Post EQ means any change you apply to input gain or EQ will affect the DI signal. It can be very frustrating as an audio tech to finally get the bass right in the mix, only for the bass player to change amp settings and mess it all up. There is also variation in where the post signal is taken. I may be before or after the master, effects loop, etc.
Note: Many amps provide a block diagram that shows exactly where the DI signals come from.
A final option would be to run a speaker level DI. This requires a DI that is designed to handle the higher voltage. Consult the DI's manual. This can be useful for tube amps as it allows you to capture any distortion or compression created in the output section. IMHO it is not generally useful for solid state amps. Also a speaker level DI will not include the filtering and tone shaping provided by your speaker. So it won't capture exactly the sound you hear on stage.
WARNING: You can't safely run a speaker level DI off a bridged amp. This includes pretty much all Class D amps.
In my experience, the EQ from your amp should have no effect on the DI sound but only affect the sound coming from whatever cabinet you're playing through on stage. I have used a number of different DI options, but they've always been connected from my pedal board (or the cable from my bass) straight into DI and THEN into my stage amp (if equipped). I can't imagine that you can get rid of boominess from FOH by using EQ on your amp as the EQ on your amp should be downstream from the DIs output. Even the built-in DI option on my amp is pre-EQ by default.. and although I CAN switch it I never would.
As for why the sound is boomy at the venue, short of using the EQ adjustment on the bass itself, I've always considered it the sound guy's (or girl's) responsibility to EQ my FOH sound to the venue. I don't get much control over what is put out from the mixing board other than what I can EQ from my bass.
As for why the sound is boomy at the venue, short of using the EQ adjustment on the bass itself, I've always considered it the sound guy's (or girl's) responsibility to EQ my FOH sound to the venue. I don't get much control over what is put out from the mixing board other than what I can EQ from my bass.
Either you plug into DI before plugging into the amp. This will completely bypass the amp and its controls. You can understand that as "pre-EQ DI".
Certain amps will offer a send/return loop - you can use that to position the DI inbetween - plug into amp - send to DI, link DI back to return - this will offer the so called "post EQ option" but it very much depends on the design of the send fx loop - some will acount for preamp, some will completely bypass it still - some will even offer more send options and routings with multiple outputs/inputs (ampeg for example) and that you need to test/check for every amp separately.
Fundamentally the Amp is NOT connected
DI splits the signal into a balanced line level (for the mixer) and an unbalanced instrument level (for the amp)
instrument level is a weaker signal, line level is louder - possibly too loud for some amp inputs.
You may have mixed up the DI out puts, but that should be rare because the balanced line level is usually XLR as mentioned
You say you did not notice which was XLR, so it's possible your amp got the wrong signal.
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Also, Wasnex explained it clearly - something I failed to mention - A vast majority of technicians will prefer you sending them a "pre-EQ" signal, meaning you would plug your bass straight into a DI then link that box to your amp.
Unless you have something very specific going on with your amp (critically defining your sound/tone) in which case there would be arguments to either speaker-DI your whole amp to the mixer or in a vast majority of such cases - simply micing your cab (cabs can and will also contribute to the tone character, ESPECIALLY when dealing with distortion) and using that as a signal, preferrably still combining the pre-EQ DI to blend those two signals for a stable and hefty tone (the so called "dry-wet" ratio).
Unless you have something very specific going on with your amp (critically defining your sound/tone) in which case there would be arguments to either speaker-DI your whole amp to the mixer or in a vast majority of such cases - simply micing your cab (cabs can and will also contribute to the tone character, ESPECIALLY when dealing with distortion) and using that as a signal, preferrably still combining the pre-EQ DI to blend those two signals for a stable and hefty tone (the so called "dry-wet" ratio).
Different stages/venues have different boominess.
Different sound guys run bass much more through the subs others.
You are probably hearing the extra boominess because or one or two of the points above.
As far as DI, it's simple when it comes to not having one built in the amp. The Bass goes into DI, DI splits out to your amp and PA. You adjust your amp the way it feels best, sound guy does their thing. You really shouldn't feel much if any difference when going through a straight DI and plugged directly in.
Different sound guys run bass much more through the subs others.
You are probably hearing the extra boominess because or one or two of the points above.
As far as DI, it's simple when it comes to not having one built in the amp. The Bass goes into DI, DI splits out to your amp and PA. You adjust your amp the way it feels best, sound guy does their thing. You really shouldn't feel much if any difference when going through a straight DI and plugged directly in.
Just to be clear; the boom you're hearing is coming from your rig and not "bleeding" from the mains? (which is very common)
I can't imagine a scenario where there signal from the board is going into your amp.
if defeating the bass on your amp had no effect - that suggests that the boom is coming from a different source...
What did the soundman or anyone else comment about your tone out front?
I can't imagine a scenario where there signal from the board is going into your amp.
if defeating the bass on your amp had no effect - that suggests that the boom is coming from a different source...
What did the soundman or anyone else comment about your tone out front?
The sound needs to be processed discretely for different uses and listening positions. The processing that works for you on stage will not necessarily work for the house mix. Likewise, the processing that works for the house mix won't necessarily work for you on stage.
There is no ideal solution because of the way acoustics work. The sound from your stage rig will typically fight a bit with the sound from the PA. Also the sound from the PA can bleed on stage and fight with your stage rig. This typically causes degradation, and in some instances the degradation can be severe. Because of this, you rarely get perfect sound.
My advice.
1. Have reasonable expectations.
2. Work with the audio tech to find a reasonable compromise. If you aspire to being a pro, I suggest prioritizing the audiences listening experience as much as possible. However, you do need to hear well enough to perform.
3. Experiment with the way you set up your rig to see if you can make it easier to hear at a lower volume. This could potentially improve what you hear on stage and reduce how much your stage sound impacts the house mix.
Regarding #3. I typically elevate my speaker and tilt it back to aim at my head to ensure I can hear the full bandwidth of my signal as it travels directly from the cab to my ears. This allows me to hear more clearly at a lower volume. However, if you prefer a big thumpy sound with no highs, you will probably hate it.
The sound from subs tends to shoot out almost equally in all directions. This means you may get a lot of sub bass on stage. There's not much you can do about this. Sometimes reversing the polarity of your DI signal can help. Reversing polarity does not fix the problem, but it can change the frequency where the problem occurs, which is sometimes useful.
NOTE: Some DIs have a polarity switch. Also most quality mixers allow the audio tech to switch the polarity on your channel.
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I would second @Redbrangus on possible DI loading a passive bass, as well as possibly hearing bleed from the PA. If your behind the PA, all the highs are going out to the room. Below about 200hz, sound starts transitioning to 4pi and starts becoming omnidirectional. This mixes with your rig accenting the low end...i.e....might sound muddy or woofy or the likes.
