Double Bass What kind of volume potentiometer?

[Francois Blais]

Isn't a potentiometer a just resistor that can be adjusted? If I measure the resistance of a 1 meg audio pot on my test meter, the measurement changes and becomes smaller as I turn the pot down. AS the resistance goes down in this scenario, doesn't it change the sound?

Yes, a pot is a variable resistor.
If the pot is the first thing element the pickup is seeing, it should change the sound. Some pickups are more sensitive to that, others less. (like the BassMax)

It shouldn't make any difference if the signal passing through the pot is passive or active, the effect of the resistance is pretty much the same on the signal it's reading, right?

A piezo pickup is a complex signal source.
The electrical equivalent has resistance , capacitance and inductance.
The pot (plus cable) you'd use has resistance and capacitance.
This is a complex chain.

Ideally, a piezo pickup should be plugged with a short cable directly into a high input impedance active buffer, with low stray capacitance, to minimize those factors.

Isn't it more advantageous to buffer a piezo pick up without any added passive load resistance of an audio pot on the pickup, taking advantage of the audio headroom the buffer provides?

Yes!
The (volume) pot will likely be at the output of the preamp, or within the feedback path of the active input device. (OP-amp, transistor, tube)

 

[Ric Vice]

Y'all hurt my head with all this gear talk. If you are willing to do all that extra wiring, putting **** on mic stands, clipping **** on you belt or tailpiece, why balk at a volume pedal idea. I use one when I have to do big rocks gigs with my BassMax because the group I play with I go between pizz and arco. It is a snap and solid factory built stuff has less chance of failure plus what's more hands free than working your volume with your foot. That's just me.

+1 simpler is always better as long at it solves the problem. With the Headway EDB-1 you really have the entire pre amp right at you fingertips, so if you have a good sound man with mains and independent monitor sends you don't necessarily need an amplifier at all. What would be better is if the pre amp were in the pedal and you had a cable to run back to a lightweight power amp speaker setup.

Ric

 

[Jack Clark]

. . . I just ordered the Fishman PLATINUM on the internet and have'nt received it yet. Will let you all know how it fits on the tailpiece on my DB and how it affects the sound. . . .
I did'nt know that the Fishman PLATINUM can be mounted on at mic stand! That could come in handy some day: I play all the time, electric and DB, and the setup is always different so you never know.

If you haven't seen and held a Plat Pro in person, you might be surprised at its size and weight when it arrives. I was. I think I'll be a bit surprised if you'll want to hang it on your bass anywhere. I wouldn't even want it hanging on my belt. I built a small shelf on the side of my instrument stand for my Plat Pro. But I don't gig, so I don't have the transport problems you have.

 

[Alain Bass]

Hello

I just recieved that news today about a Volume Control Cable:
Invalid Link Removed

 

[davidilag]

Hi Alain Bass

That looks great; a jack with built in volume pot. It may be the answer to all my prayers

 

[Francois Blais]

Pot resistance is only 250K.
Your Shadow will sound very thin and shrill with that...

 

[davidilag]

They make them in 500K also, but I think I will need it in 1M Ohm.

 

[Francois Blais]

As suggested previously, your best option is to get a Series II HPFpre from Fdeck and mount it on the back of the tailpiece.
You'll find the Pro Plat much too big and heavy for that purpose anyway. (also noted earlier)

 

[MR PC]

David, Francis is right about the fdeck pre. Not only will it fit buffer your pickup, it's lightweight and will fit nicely on your tailpiece. I think 1meg is a good choice for a passive volume control, but still without a preamp in front of it the quality of your sound will suffer.

If you choose a pot with a value of more than 1 meg, I'm not sure that the pot would have much of a taper for controlling the volume. I think it will begin to function more like an on-off switch. Somebody please correct me if I'm wrong

The Fishman is a really nice unit, I'd like to have on in my box, but I think if you check out the fdeck, you will find that it's going to get the job of buffering your signal done, as well as providing a very well designed adjustable high pass filter. It's lighweigt, compact, and also a tremendous bargain.