Warwick Thumb 4NT Distorting

[KennysFord]

Hey Folks,
My 2002 Thumb NT4 has started distorting when I dig in on the E with the Bass up to about 3/4's or above.
I've tried a couple of different batteries (both good) and it's not that.
It's fine on the A string from C up but pretty bad on the E string from A down, awfully bad when digging in on the open E.
If I knock the bass back to 3/4's it's gone.
Any ideas or suggestion would be greatly appreciated.
Thanks.

[Fionn]

On the circuit board in the electronics compartment on the back of your thumb bass you'll see a little trim pot with a slot in it. You can reduce the output of your bass by turning this.

I'm thinking this will solve your problem.

[Guest]

Superb,
Thanks Buddy, I'll have a look now and report back.

[Guest]

And...........Sorted,
Cheers Dude, that's your good deed done for the day.
1 clean sounding Thumb Bass.

[Fionn]

Nice one man

[Guest]

Cheers.

[mart]

That trim pot is there to balance the active/passive sounds (or, to be precise, the preamp/preamp-bypassed sounds). How do the volume levels compare now when you pull the volume control (to bypass the pre)? Of course, it maybe that a previous owner tweaked the trim pot to get a much louder volume from the preamp than when bypassed.

[Guest]

Hi Mart,
To be honest Bud I've not really used the Bass much in passive mode so I can't be sure.
I'll have a twonk later though and report back.
Cheers Bud,
Pete.

[mart]

[quote name='kennyrodg' timestamp='1360433287' post='1970413']
Hi Mart,
To be honest Bud I've not really used the Bass much in passive mode so I can't be sure.
I'll have a twonk later though and report back.
Cheers Bud,
Pete.

[/quote]
I suspect you're not alone in that: I'd guess that most people try both modes and then quickly decide which one they prefer, and then stick with it.

And I suppose there'll be some who religiously use the bypass mode because they think it'll save battery life. (Which it won't, since the preamp is powered whenever there is a lead plugged in.)

[Guest]

I'm not keen on the passive tone at all really. Active on the other hand.....tis a wonderful thing
I've had the bass for approx 3 months and the battery I took out was showing 8.3 volts. It's been played every day and done 15 or so gigs so I think it's pretty kind on batteries.
I was tempted to say something like "I'll be keeping my knob pushed in" but thought best not to

Edited February 10, 2013 by kennyrodg

[icastle]

[quote name='kennyrodg' timestamp='1360519744' post='1971656']
I've had the bass for approx 3 months and the battery I took out was showing 8.3 volts. It's been played every day and done 15 or so gigs so I think it's pretty kind on batteries.
[/quote]

You can't measure battery efficiency like that.
They have different discharge characteristics depending on the composition of the battery (i.e. it may show a reasonable voltage but not have enough current to power a device).

[quote name='kennyrodg' timestamp='1360519744' post='1971656']
I was tempted to say something like "I'll be keeping my knob pushed in" but thought best not to

[/quote]

Probably for the best

[Guest]

Aah OK,
I have a multi meter, is there anyway I can measure the current to check my Batteries in future.
I've always done it with voltage and hadn't realised it was not the way to do it.
Cheers icatle.

[icastle]

[quote name='kennyrodg' timestamp='1360524229' post='1971786']
Aah OK,
I have a multi meter, is there anyway I can measure the current to check my Batteries in future.
I've always done it with voltage and hadn't realised it was not the way to do it.
Cheers icatle.

[/quote]

Well to measure current you need to 'break' one of the power leads and put your meter (set to amps)in series with the circuit.

Not very convenient though.
The easiest way (although still not very accurate) is to take a voltage measurement with the battery under load and make a point of making a note what reading you get when the battery goes 'flat'.
Once you have that then you'll at least have a 'figure' to work to.

I use a really low tech method - I know roughly how long the batteries in my bass last and keep a spare in the case with the date I installed the last battery written on it.
I might throw away a battery with a week or so left in it, but I've never had a battery go dead on me during a gig.

[Guest]

Cheers icastle.
I think I'll be doing it the lo tech way then from now on. hehe.
Cheers all the same.

[icastle]

Sometimes low tech is the best tech.

[mart]

[quote name='icastle' timestamp='1360531299' post='1971982']
Well to measure current you need to 'break' one of the power leads and put your meter (set to amps)in series with the circuit.

Not very convenient though. ....
[/quote]
I have done this a couple of times with my basses: just disconnect the battery from its clip, then rotate it 90 degrees so you can connect one terminal but not the other, and then put the multimeter across the two unconnected terminals. That will tell you how much that particular circuit is drawing.

But although that is interesting, icastle's approach is more use in practice.

Edited February 11, 2013 by mart