active tone/Buffer for bass guitar??

[partyjups]

Hi I have a 5 string G&L bass with build in active electronic.

I think it,s baxdale concept with 2 band one for bass on one for treble. It don't sound good!!

if the bass control isn't fully turned up the sond get's thin.

I wan't to build a similar setup with bass and treble control
witch is using discret fet insted of op amp.

does anybody know of an already made circuit???

Or have a circuit that i can use??

thanks JC Denmark

[sreten]

As a bass player I think the following comments are fair :

Highly unlikely G&L have screwed up their EQ.

The basic bass sound is set on the amplifier with all active controls set
to flat, i.e. active on/off (my bass has this option) is a usable option.

The active controls are used for song to song variations, or
sections of songs, along with the pickup selector variations.

Any modifications to a good bass (i.e. expensive which G&L are) should
only be acknowledged and accepted modifications (expensive again).

sreten.

[partyjups]

Hi I have played bass for 20 years and I know that G&L makes great stuff but the way my EQ is working is not good. I Think you are right that it's a good design. so I will try to find out if somethings wrong with my one. Can the op amp get damaged?

The design is maked that way thet it's not posible to truly bypass the eq,
Tone still work like a pasive cut filter option. . when I sw to pasive mode it's loose some of the briliance
in the sound. Im preatty sure that the signal lsot something through the circuit.
I tryied to look for the circuit on the net I have found it before but I coudent find it now.
My bass i a G&L 1505

thank for your coments JC Dk

[sreten]

Op-amps can be not working and the signal stilll finds a way around them.

Set to flat if active has less bass than passive, and you need to
to turn up the bass control, something is definetely wrong.

What op-amps are used ?

sreten.

[partyjups]

Ive opned and the op amp is a LF 441 cn
looks like it's from national semi...
I will try to replace it and see if it's solves the problem.

greatings from JC dk.

[partyjups]

Hi I have changed th op amp and it's still sound to me more like a cut funktion than a boost and cut control to me it's sound like the circuit is making the signal week even when it's run in bypass mode.

I have tryed to attach the circuit.

im about to change the hope circuit to a musicman based circuit layout.

any advice is wellcome jc dk.

[phase_accurate]

The controls are indeed cut functions. Which is not that unusual with passive gutars and basses.
Some even have a "high" pot only (at least on my basses). I always had them fully open and made every sound settings on the preamp (also the loudness pots).

Regards

Charles

[sreten]

All is perfectly clear now.

You do not have active tone controls.
Your tone controls are not Baxendall.

What you have is a switcheable active buffer, which tonally
is a fat lot of good to a bass player. The buffer will prevent
the treble loss from your cable making the sound "thinner"
(like I said a fat lot of good to you), its main advantage
is that it allows you to use very long cables to your amplifier
if you needed to without losing the midrange.

I've seen this in other basses (Hohner B2A - A for active) and
some guitars - at least with guitars it makes some sense.

The Musicman circuit should be more to your liking,
I know for sure the tone controls are active.

sreten.

P.S. I apologise for suggesting that G&L wouldn't screw up
the controls on their basses, the "bass" control is a joke.

[partyjups]

Hi again im trying to find a circuit (musicman) on the net but it's difikelt to find the circuit so that i can recunstrunt a layout and build.
do you know of and good active circuit bass and treble controle + buffer circuits .

thanks jc.

[sreten]

using this info :

http://www.redcircuits.com/Page69.htm

and this info :

http://www.redcircuits.com/Page53.htm#Tone

You should be able to manage it.

You can leave out the middle arm if you want,
but why not leave it in.

1/2 the values of the capacitors in the mid / treble
sections of the circuit to make it more suitable for bass.

By increasing the value of the resitors either side of each
pot, you can reduce the adjustment to something more
sensible, I'd suggest +/- 10dB is all you need.

Your diagram doesn't show it, but you should use the input
jack as a switch for the battery.

sreten.