random, sporadic "pops"

[dg27]

I record bass using a SansAmp Bass Driver DI.

From that I route an XLR direct (untreated) into one channel of my PreSonus BlueTubev2 preamp (which routes through my MBox3) and a 1/4" jack (treated w/ my BassDriver settings) into a another channel on the PreSonus.

Each get their own track in Pro Tools and I route those to a bass bus aux input.

99% of the time I love this setup and find that with a combination of the two tracks I can get exactly what I need in terms of tone (I'm a bass player and a stickler with this.)

But what occasionally happens is that I will get a single, very slight pop somewhere in either one or both of these tracks (if it's on both tracks it's in exactly the same spot). It doesn't happen all the time and it always seems to happen only once.

It's barely noticeable, but when it happens, for me at least, it sometimes ruins an otherwise good take.

Any ideas as to what could cause this? For the record, I don't run any plugins on these tracks when I'm recording.

Also for the record, I always make sure that my system isn't running other programs, browser windows, etc. When I'm recording that's all that is active or running.

Running PT 11.3, Win 7 Pro 64X; Intel Core i7 960 @ 3.20GHz, 24.0GB Triple-Channel DDR3. Pro Tools project files on a dedicated internal HDD. PT running off a Samsung 840 Pro SSD.

[musicman691]

If you can lose the Presonus between your bass and audio interface. If you don't get the pop then it's in the Blue Tube. If that's the case you might have the 12AX7 in the BT going bad. Another possibility is, and this depends on how Presonus designed it, but the BT might be running what's called a starved-plate design where the tube doesn't get the full voltage on the plates to properly run the tube. That will compromise the sound and could give out what you're hearing.

[dg27]

Thanks, Jack. I will check these issues out. Hopefully it's the tube; the PS is only 6 months old, but I do use it every day. There is also an option on the PreSonus (a saturation knob) that, when defeated, bypasses the tube entirely. I've always left a nominal amount of saturation; I'll try it without and see what happens.

It doesn't happen often often for it to be a major concern and like I said, the pop (it's always only one) is really very, very faint. I doubt others other than engineers would even notice it.

What's annoying is that when it does happen, it's always on a take I really like .

dg

[albee1952]

Another possibility: if your playing gets vigorous enough, could it be a string hitting a pickup? Or the pick(if you play with a pick)? I get loud ticks on acoustic guitar(depending on the player) and its almost always the pick hitting the body

[musicman691]

Another thought which goes along with hard playing - strings slipping in the bridge or nut when doing bends.

[dg27]

Thanks, Jack and Dave.

I don't think it's a mechanical noise, mostly because, for one, it definitely does not correspond to any "hits" (I play with a heavy pick). And if it did I could probably live with it. But this is very random and definitely offbeat and has a "digital noise" sort of sound.

I just checked the most recent occurrence and it happened when I was holding a long note.

[musicman691]

Originally Posted by dg27

Thanks, Jack and Dave.

I don't think it's a mechanical noise, mostly because, for one, it definitely does not correspond to any "hits" (I play with a heavy pick). And if it did I could probably live with it. But this is very random and definitely offbeat and has a "digital noise" sort of sound.

I just checked the most recent occurrence and it happened when I was holding a long note.

Did you do any bending of the note? Was this on a wound string?

Are there any cfl light bulbs in the area? Those'll put out noise like crazy.

I know I mentioned the tube before - see if you can get a new one and pop it in in place of the one already there. Even better before you do that or anything else - lose the Blue Tube and see what happens.

The SansAmp - are you running off the internal battery or phantom power?

[dg27]

Originally Posted by musicman691

Did you do any bending of the note? Was this on a wound string?

Wound string, no bendng when it happened.

Originally Posted by musicman691

Are there any cfl light bulbs in the area? Those'll put out noise like crazy.

YES! There is a CFL in the same room, though not plugged into the same circuit as my computer and the BT, etc.

Originally Posted by musicman691

I know I mentioned the tube before - see if you can get a new one and pop it in in place of the one already there.

I'll try this.

Originally Posted by musicman691

Even better before you do that or anything else - lose the Blue Tube and see what happens.

I'm hoping it's not the BlueTube because I get much better bass tone with that than I ever did with my MBox 3.

Originally Posted by musicman691

The SansAmp - are you running off the internal battery or phantom power?

I'm running an XLR and 1/4" from the SA to the BT. The XLR is phantom. The SA is plugged into my pedal board, which has a Voodoo Lab ISO-5. That is plugged into the same wall outlet as the CFL. I think this could be the problem.

Last night I recorded 4 takes with the identical setup and setting and had no pops. For the record, the CFL was off.
I'm sure it was on when I had the last incident because it is only on during the day.

Thanks for all the suggestions!

[musicman691]

Originally Posted by dg27

Wound string, no bendng when it happened.



YES! There is a CFL in the same room, though not plugged into the same circuit as my computer and the BT, etc.



I'll try this.



I'm hoping it's not the BlueTube because I get much better bass tone with that than I ever did with my MBox 3.



I'm running an XLR and 1/4" from the SA to the BT. The XLR is phantom. The SA is plugged into my pedal board, which has a Voodoo Lab ISO-5. That is plugged into the same wall outlet as the CFL. I think this could be the problem.

Last night I recorded 4 takes with the identical setup and setting and had no pops. For the record, the CFL was off.
I'm sure it was on when I had the last incident because it is only on during the day.

Thanks for all the suggestions!

Looks like you have it figured out for the most part. One thing I see if I read this right - you have the pedal board plugged into the same circuit as the CFL and the rest of your rig plugged into another circuit? This would to me imply two circuit breakers - you really should have everything plugged into the same circuit.

And I'd get rid of that cfl and either go to a traditional bulb or an led bulb. CFL's create noise and when they break you're dealing with hazardous waste; as a matter of fact in most places when one dies it has to be treated as hazardous waste and not go in the regular trash.

[dg27]

Originally Posted by musicman691

One thing I see if I read this right - you have the pedal board plugged into the same circuit as the CFL and the rest of your rig plugged into another circuit? This would to me imply two circuit breakers - you really should have everything plugged into the same circuit.

Never knew that and wouldn't have thought of it--thanks. It's just a logistical issue in terms of the room; will have to figure out how to route the pedalboard to the other side of the room.

Originally Posted by musicman691

And I'd get rid of that cfl and either go to a traditional bulb or an led bulb.

The CFL is a plant bulb, actually. It's been there for ages...will get rid of that.

Thanks for all your help. It would appear that the CFL is the culprit, especially since this problem seems to crop up only when that's on.