Preamp overdrive

B

BTBBoi

Nov 5, 2021
10
6
781
#1
Greetings fellow Barons of Bass!
I have an Ibanez BTB 765, recently purchased new. I've discovered that with the instrument volume maxed, I get a lot of distortion and splatting through both of my amps , a Behringer BX3000 head + Hartke 4x10 and a Behringer BX1800 combo.
I did not have this issue with my old Rogue fiver, and I'm wondering if this is just new tech meets old, i.e., amps can't handle signal from the bass preamp.
At this point I'm playing at 50% instrument volume to avoid the issue.
Thoughts?
Suggestions?
Thanks!
 
#8
Is the Rouge you’re comparing to all passive? It sounds like your Ibanez may just have higher output and is causing some amp distortion. If this is the case you could use the active or padded input on the amp if there is one, turn down the volume on your bass, adjust the output trim pot inside the control cavity, again if there is one. It’s not an age issue with your amps, if you have things set up for a lower output instrument and plug in a higher output one and use the same settings any amp could distort.
 
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#9
Matt Liebenau said:
Is the Rouge you’re comparing to all passive? It sounds like your Ibanez may just have higher output and is causing some amp distortion. If this is the case you could use the active or padded input on the amp if there is one, turn down the volume on your bass, adjust the output trim pot inside the control cavity, again if there is one. It’s not an age issue with your amps, if you have things set up for a lower output instrument and plug in a higher output one and use the same settings any amp could distort.
Click to expand...

Yes, the Rogue was passive. Made lots of adjustments with the new active electronics. My smaller amp has no padded input, but it didn't make a difference on my main rig, which does have it.
As far as a trim pot, I wouldn't know it if it poked me in the eye. I'll have to Utube to get some tutorials. I'll try adjusting pups first.
 
#10
Your bass boost is doing it along with the volume level. There is nothing wrong with your BTB at all. SRs do the same, having the same EQ circuit. One way to bring out the lows without boosting them as much is to cut the mids as you have and put the mids switch down to cut at 700Hz. Backing off the volume won't do any harm with the bass boosted; switch off the active EQ, and you will hear a drop in volume. Backing it off only brings it down to the same volume as playing passive. I don't have my SR volume all the way up when in active.
 
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#11
themickster said:
Your bass boost is doing it along with the volume level. There is nothing wrong with your BTB at all. SRs do the same, having the same EQ circuit. One way to bring out the lows without boosting them as much is to cut the mids as you have and put the mids switch down to cut at 700Hz. Backing off the volume won't do any harm with the bass boosted; switch off the active EQ, and you will hear a drop in volume. Backing it off only brings it down to the same volume as playing passive. I don't have my SR volume all the way up when in active.
Click to expand...
I don't think I have a bypass.
Do I?
That would be amazing.
 
#12
BTBBoi said:
I don't think I have a bypass.
Do I?
That would be amazing.
Click to expand...
I'd say check for a bypass by giving probably your master volume knob or maybe the pickup blend knob a little pull to see whether either one "clicks" into and up position. That's usually where one of those bypass switches hides in plain sight - but I have no idea if that bass includes one.

I have a bypass on two different basses; one has this push/pull selector in the master volume and the other has its own little micro toggle switch that's separate from the other controls. It looks like your bass has a toggle switch to select the center for your preamp's mid control.

The suggestion for turning down the volume on the bass sounds good, especially if you don't have an input gain control on one of your amps. But along the lines of the advice in post #10 above, you might also get toward the tone you want without overwhelming (distorting) your amp if you try setting your bass preamp controls flat and then do the boosting and cutting of your frequencies at your amp.

Looking for a trim pot in your control cavity is pretty simple. They're typically placed in the cavity for easy access once the cover is out of the way. You can pop the cover off and see if there's a tiny module looking up at you that can be rotated with a little jeweler's screwdriver - the last one I tweaked in my own bass was a flat head, not a Phillips head. If there's nothing in plain sight, it's probably not there. No need to go poking around and risk disturbing the circuits.
 
#13
BTBBoi said:
I don't think I have a bypass.
Do I?
That would be amazing.
Click to expand...
My mistake. You don't have a bypass; it's on BTB Premiums. Everything else is as I said, and there's still nothing wrong with yours for overdriving. My two SR300Es are the same. There is a YouTube somewhere on how to take the active board out and run as passive. I thought I would want to go passive, but the tones make it worth keeping to active.

Your BTB has a page on Ibanez.com BTB765 | BTB | ELECTRIC BASSES | PRODUCTS | Ibanez guitars
 
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#15
If there’s a trim pot it probably looks like this. It should be right there once you remove the back cover if there is one there at all.

9F5A55BA-7CA7-4E8E-AB8A-08A8C08DA329.jpeg
 
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#18
Many Preamps have a center detent for each knob(pot). This is usually flat and equal to what it would be with the active part bypassed. If there's no center detent then you can just back each knob down to 50% and take it from there.

Edit: I see your controls are all listed as Boost/Cut. Therefore you can definitely set them in the middle for flat and adjust as needed.

eb_control_44.jpg
 
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#19
Well, I wasn't wrong.

The preamp was indeed over driving the signal. Because the operator had the bass pot jacked all the way to 11!

This is, I presume, part of the learning curve moving from my old cheap (passive) Rogue to the wonderful world of active electronics.

I set all the EQ pots to the center detent and Lo! The wonderful tones that emanated from my amplifier! The little BXL1800 still isn't as punchy and warm as my big rig, but it's sounding much better than the fuzz I was getting previously.

I have done penance by playing along with Headlong Flight and Cygnus X-1, two of my favorite Rush tunes.

Thanks ever so much for everyone's patience and advice.

Incidentally, no trim pot on the board.

PS: I did find that the battery connection was a little loose, so I tightened that up, and the battery itself was fine, but that wasn't the issue anyway.
 
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