building an outboard preamp using an onboard preamp?

[sheepdog]

I have recently become infatuated with the audere preamps, especially the 4 band. If I had the proper box to put it in, is there a reason I could not put the 4 band preamp? Seems like it is just a matter of wiring a 1/4" input and output to the box.

[A9X]

Originally Posted by sheepdog

I have recently become infatuated with the audere preamps, especially the 4 band. If I had the proper box to put it in, is there a reason I could not put the 4 band preamp? Seems like it is just a matter of wiring a 1/4" input and output to the box.

There is no technical reason why not, unless the Audere has some really unsual circuitry or requirements (not likely). Just use a decent case, connectors etc. I'd use a die cast Al case and put the in and out connectors on the same side so that when the case is attached to your strap/belt they're both at the bottom.

[Funky Doctor]

You could go one step further and put a footswitch and an led in that box too...

[A9X]

Originally Posted by James Hayes

You could go one step further and put a footswitch and an led in that box too...

For a floor based box, add a regulator and an external PSU. No need for battery powering if it's not attached to you.

[Audere]

Originally Posted by sheepdog

I have recently become infatuated with the audere preamps, especially the 4 band...

Originally Posted by Dharmabass

There is no technical reason why not, unless the Audere has some really unsual circuitry or requirements (not likely).

I agree - it was not likely but true in this case
Most preamps are just active tone controls
The Audere is a different cut on the problem



To break down what an external box could do:

The 4 band tone controls would work just like today

The battery meter etc would work

The active balance will not work - but maybe not a big deal to you

The High Z-Mode will not work as designed - it will become the current Mid Z-Mode

The Mid Z-Mode will work but if there is much difference between it and the High Z-Mode then it will probably become too dull

The Low Z-Mode will work but not as designed - gets complex in this case...



So if what you really want is the 4 band tone control feature then that could work.

David

[A9X]

Originally Posted by Audere

I agree - it was not likely but true in this case

I don't have the schem in front of me, so I was just guessing how you'd implemented it, hence the caveat. I guessed you'd chime in yourself eventually.

[Antman3820]

I used an Aguilar OBP-1 onboard pre and turned it into an outboard...........Very easy......I use it for a different tone, when I put my Stammy in Passive mode. I am thinking of doing the same thing with a Bart Pre......

[sheepdog]

Originally Posted by Audere

I agree - it was not likely but true in this case
Most preamps are just active tone controls
The Audere is a different cut on the problem



To break down what an external box could do:

The 4 band tone controls would work just like today

The battery meter etc would work

The active balance will not work - but maybe not a big deal to you

The High Z-Mode will not work as designed - it will become the current Mid Z-Mode

The Mid Z-Mode will work but if there is much difference between it and the High Z-Mode then it will probably become too dull

The Low Z-Mode will work but not as designed - gets complex in this case...



So if what you really want is the 4 band tone control feature then that could work.

David

It would mainly be the four band eq I was interested in. Any volume/balance controls would remain on the bass.

I would use an outboard power supply, but simplicity dictates sticking with battery supply.


THANKS!

[Captain_joe6]

You could always run a stereo cable from the bass with one conductor for each pickup and a common ground. That would give you blend on the outboard box. And it'd be nicer blend, too, because its active.

[sheepdog]

Originally Posted by Captain_joe6

You could always run a stereo cable from the bass with one conductor for each pickup and a common ground. That would give you blend on the outboard box. And it'd be nicer blend, too, because its active.

I had actually thought of that already, but then it would be a problem if any future basses did not have stereo output. I would rather stick to mono out to avoid complicating it. Good idea, but don't think it is worth the hassle.

[Captain_joe6]

Would it though? If you plugged a mono jack into it, wouldn't each side of the active blend see the exact same thing, essentially defeating it and passing the signal right on through to the Z-mode and tone controls?

[sheepdog]

Originally Posted by Captain_joe6

Would it though? If you plugged a mono jack into it, wouldn't each side of the active blend see the exact same thing, essentially defeating it and passing the signal right on through to the Z-mode and tone controls?

I'm not sure. Perhaps someone more knowledgable than I am could jump in on this one.

[ScubaSteve]

Well if it's just the EQ you want, why not go with a rackmount 31 band graphic EQ or a parametric EQ ? The whole idea to the onboard preamp is buffers for each individual pickup which you wont get unless you run a stereo cable.

[Audere]

You can use a stereo cable to export the pickups.
The cable will add some capacitance to the High Z-Mode but this is not a problem with most pickups as the C it adds is less than the C most players select.

I do this sometimes for testing and have some very thin shielded dual conductor cable I can send you to experiment with. It easily goes though a standard output connector...

Originally Posted by ScubaSteve

Well if it's just the EQ you want, why not go with a rackmount 31 band graphic EQ or a parametric EQ ?...

Most rack mount EQs have a load which would be a little hard to drive - depends on the unit.