Active Bass with Weak Signal - Not Battery Related

[oscar6]

My Rockbass (Corvette Clasic) produces a very low signal when played. I can hear notes "clearly" if I crank the volume knob on my amp all the way up.

I've tried two new batteries that are different brands and both produce the same weak signal.

Perhaps anyone could help pinpoint a specific area that I should look into? Do guys think this would be easy to repair?

 

[bongomania]

I would clean the jack and pots with a good contact cleaner, and check the wiring for any weak-looking solder joints.

 

[therex]

sounds like a faulty cable, if not it could be the pots or jack in the bass so check that too

 

[Absentia]

Raise the pickups

when you press the strings down on the last fret you should be able to just fit a 5/32 allen wrench between the pickup and the string. I had the same problem (after a very stupid and embarrassing thread) with my corvette now the sucker sings.

 

[TerenceSharp]

I had the same problem with my stingray.

The battery connector wires had ripped themselves loose.

 

[Marley's Ghost]

^^ Same thing happened to my Stingray.

 

[phatbass]

I don't know about the Warwicks, but quite often on active basses there will be a gain adjustment on the circuit board. Take the cover off the back of the Bass and you will see a trim pot that needs a small screwdriver to adjust. Be careful as they can be a bit delicate.

Just to give you an idea, here's a pic of the Ibanez ATK300 one:

http://www.talkbass.com/forum/showthread.php?t=512551&page=9

Page 9, post #177 - the trim pot screw is circled in red.

 

[N8116B]

My Rockbass (Corvette Clasic) produces a very low signal when played. I can hear notes "clearly" if I crank the volume knob on my amp all the way up.

I've tried two new batteries that are different brands and both produce the same weak signal.

Perhaps anyone could help pinpoint a specific area that I should look into? Do guys think this would be easy to repair?

Did it work at one time?

If so something is now not working.

First: check all the battery wires, are they still secure. Can you also measure the voltage on the preamp board itself to see if something went wrong with the battery hook up?

Second: Are the connections clean? If not clean them with some circuit cleaner or an emery cloth. Do you have another cable to use? If so try it. Maybe a bad cable.

Third: Is it only this bass on this amp? IOW are other basses playing ok on that amp? This is to eliminate the amp as being the culprit. If other basses have a similar problem it is you amp that is broken.

Fourth: If you have eliminated the cable, amp, and power to the preamp issues it is time to think that maybe the preamp itself has gone TU. For that you need to go to a service shop. Can you bypass the amp and see if your signal improves?

Fifth: After having done step 4 there is still weak signal take a look at the string to pickup distance. Anything change since it worked last?

Sixth: Check that the pick up pots and wires are still hooked up correctly and have not come loose or dirty.