Active Bass vs guitar effects...

[jaman]

Hello,

I searched for a while older posts, but I didn't come to any solution for this problem :

I would like to use some effects (a Ross Compressor for example) with a bass with active pickups.

The result is, no compression at all, gain, and lower output than bypassed.

Is there any solution ?

a buffer maybe ?

thank you

[George Giblet]

Are you sure the effect is working?

It could be that you have so much output that gain control cannot reduce the gain further.  In this case the unit will operate as a fixed attenuator, except perhaps at the tail of the note decay.   You should be able to hear compression with light picking?

The simple solution is not to advance the gain/compression so far.

You can do other mods.  For example increase the 15k at pin 3 of IC1 to 33k and decrease the 10nF cap to 4n7.  All that does is effectively decrease the input level.

[jaman]

Hello,

the effect is working great with guitar.

I am asking if there is a general solution for most guitar pedals so that can be used with active bass. (The problem is not only with the Ross, but with other pedals too).

thank you !

[loki]

it is my experience that Fx pedals dont respond well to active basses, I guess that in general (with some exceptions of course), they are not conceived and built for active instruments. my pedal board sounds great with my passive j-bass and sounds like sh*t with my active yamaha. A friend of mine that plays electric violin (active) had the same complaints with his pedals. He ended up using a Sansamp paradriver as first pedal in the chain just to handle the active signal and then all the other pedals after it. Now they sound great, he says... maybe you should try something similar with the bass, getting a pedal which can somehow "tame" the active signal and then put all the pedals after it...
I dont use my Yamaha anymore so i havent personally tried anything to solve the problem...

[jaman]

That's what I am asking.

Obviously the sansamp should work like a buffer.

What kind of buffer could I use in front of a pedal so the active bass will sound properly ?

thank you !

[theblueark]

How about using pickup simulation?

http://www.muzique.com/lab/pickups.htm

[jaman]

Has anyone tried this ?

does it work fine ?

[petemoore]

  yes it works fine. It puts a coil in the signal path.
  ..Not at all sure it will serve this intended purpose.
  First thing I would try is turn the guitar volume down, maybe most of the way, and see if the compressor doesn't 'rise', it could be the output level of the bass is well above what the compressor expects to see [~=passive HB with guitar] and the input levels are 'diming' the attenuation/compression level, reducing output.
  If that works, a pre-gain could work same trick.
  I'd wait to see if someone else doesn't chime in, Bass/Compression is a ~ common goal, I would imagine Active PU's have run into dynacomps before.
  What kind of buffer could I use in front of a pedal so the active bass will sound properly ?
  the output of your bass is low impedance, probably a buffered output.
  Passive pickups..there I said it, but it ain't gospel by any means..
  Transformer to match impedance...not sure it'd help, expensive/large..

[George Giblet]

>What kind of buffer could I use in front of a pedal so the active bass will sound properly ?

A buffer won't do what you want.  The output of an active bass is usually a fairly low impedance.  A buffer converts high output impedance to low impedance - the active bass already has that.

>does it work fine ?

There is no general solution.

There are a few characteristics of an active bass which can change the sound of an effect. 

The usually output level is higher.  This can throw out effects which are designed for passive output levels.  That is probably what's  happening with the Ross unit.  It can also cause clipping within the effects pedal.  Any form of clipping will affect the sound.  The solution here is to simply dial back the volume.  Alternatively build an attenuator which does that.  Overloading chorus, flanger and phaser units would benefit from attenuation.

The tone can be different.  Sometimes the extra high-end from an active bass can sound bad.   Some active basses have built in EQ  even when the tone controls are flat, usually in the form of mid cut, others end-up having EQ simply because the EQ controls are not flat in use.

Output Impedance.  Effects like the Fuzz Face required interract with the impedance of the pickup.  The low-output impedance of an output active bass will have a different interraction (usually no interraction).

The pickup simulators act to cut high-end and emulate the impedance of a passive pickup.  It won't fix the output level (you could add that in) but it does address the second two issues.  It won't fix the Ross problem, because that is level related.  The problem is it will cut the high end of the bass all the time, effectively trying to make it sound passive - you might not want this.