Classic Preamp Series - Frequently Asked Questions

Compared to a JZ3, JZ3D, JZ5D, JZ6D, Pro JZ3, Pro JZ3D or Pro JZ6D  Preamp - how is the Classic preamp different?

We are happy that you have one of our jazz preamps...

The Classic preamp is a configured module preamp so the preamp is in a small plastic case and the pots are on wires so they can be moved around based on the holes in your bass body.

This preamp series does not include the Z-Mode system - it sounds just like the Mid Z-Mode setting of the current Pro JZ3 preamp. This is the setting which sounds like your passive bass when the Z-Mode switch is centered.

The LED Battery Meter is an optional accessory on this preamp series.

It will still have the touch response so many players love about our systems.

The Tone controls will be the similar - same quality and S shaped response curves etc.

All pickups, including active, will work with this preamp.

You must solder the pickups to the input wires.

The pickup commons can be grounded on this preamp series which makes instillation easier for some pickups.


Compared to a Pro Z Preamp - how is the Classic preamp different?

We are happy that you have one of our module preamps...

This preamp series does not include the Z-Mode system - it sounds just like the Mid Z-Mode setting of the current Pro JZ3 preamp. This is the setting which sounds like your passive bass when the Z-Mode switch is centered with stock Z-Mode switch programming.

The Advanced LED Battery Meter is not present on this preamp series but a simplified LED Battery Meter is offered as an optional accessory.

It will still have the touch response so many players love about our systems.

The Tone controls will be the the same - same quality and S shaped response curves etc.

All pickups, including active, will work with this preamp.

The pickup commons can be grounded on this preamp series which makes instillation easier for some pickups.


My package includes optional coupling capacitors?

The capacitors will allow you to use a classic preamp with active pickups, pickups with pole pieces connected internally to pickup common, and can also be useful in cases where you want or need to ground the pickup common(s) for other reasons like to simplify wiring changes.

The 2 capacitors are connected in between the pickup hots and the preamps inputs - one for the bridge pickup connection to the black/white bridge input and the 2nd one for the neck pickup connection to the blue/white neck input.

The capacitors are high quality 0.39 uF metal film parts and will not negatively affect the sound.

To install solder one capacitor wire to one side of the cap and insulate it with heat shrink.

Solder your pickup hot to the other side of the cap and insulate it with heat shrink.

Connect your pickup common to ground.

The green/wire will not be used so insulate it.



My package includes an extra battery clip?

There is normally no significant benefit to running Audere preamps on 18 volts since we do not put large amounts of gain in our preamps like many other vendors do.

However if you play very aggressively with loud pickups and lots of tone control boost then you my want to convert to 18 volts.

The extra battery clip allows you to re-wire the preamp to run on 18 volts.

Connect the 2 battery clips in series by cutting the red wire shorter on one of the clips and black wire shorter on the 2nd battery clip.

Stripping the ends of the cut wires and soldering the first black to the 2nd clips red.

The pair to battery clips will now have 2 free ends - one red and one black.

The red goes to the red wire coming from the preamp.

The black goes to the short black wire coming off the jack's ring connection.

Insulate the connections with heat shrink when done.



Will this preamp fit into my Bass Electronic Cavity?

Probably - the preamp easily fits into most cavities.

The module X dimension is 2", the Y dimension is 1.05" and the Z dimension is 0.3"





Our custom pots are higher quality and smaller than the typical parts used in guitars.

The body is the same size for the single and stacked pots but 2 sections are included with stacks so the pot will extend farther into the cavity.





The optional Classic LED Battery Meter dimensions.





How is the preamp module mounted?

We supply double sticky hook and loop pads to mount the preamp to the side of the cavity wall.

If you are low on space the preamp can be mounted to the backside of the electronics cover.


How is the optional LED Battery Meter mounted?

Drill a #31 or 1/8" hole and mount by the LED going into the hole. See the Installation Instructions.


Electrical connection to wires on the back of the preamp?

The wires on the back of the preamp must not touch an electrical conductor like any copper shielding in a cavity.

This is normally not a problem but you can cover the wire ends with electrical tape as an insulator if needed.



How do I Solder Ground Wires to the back of the Pots on the Circuit Board?

Do not attempt this - crimp or solder all the ground wires and pickup commons together with the gray/white wire off the jack.

FYI - soldering to the back of pots was always a bad idea, even in Leo Fender's days...


Will it work with coil tapping switches?

Yes - it can be easier to add the coupling caps and connect the pickup commons to ground.

Special note - a separate coil tapping switch for each pickup can be nice.


I have a PJ - Will it work?

I have a J Hum-bucker - Will that work?

Yes to both, and it will sound great - our stereo front end separates the P and J inputs (or J and Hum-bucker) so they sound better.

You might want to reduce the volume of the P relative to the J with the gain controls to balance them up better.

If your J pickup is not a Hum Canceling type of pickup then the Hum will increase as you turn the balance toward that pickup.


Does this preamp work with Hum Canceling pickups?


Note - shielding hum canceling pickups is often overlooked and important to get the lowest noise levels.


Is shielding the pickups a good idea?

Always if well done and it can reduce the noise in a lot of cases.

One thing we commonly see done incorrectly on shielding is not grounding it correctly - non grounded shielding is an antenna for noise.


Which wire color is pickup Hot?

It completely depends on the pickup maker and version - so check their website.


Can I Install the Preamp myself?

Maybe about 50% of this model are installed by players - see the Instruction PDF


How long does it take to get my preamp in the US?

This series of preamps are configured to order - this normally only takes 2 business days for the build.

We do not control the postal service and how long they take to deliver the product but they have been surprisingly fast on average.

We ship First Class Mail in the US. Priority can be offered and is normally faster (most often by 1 day) but this upgrade will increase your cost.


How can I get it Overnight?

Sorry - we do not ship overnight - FedEx, UPS and USPS have been very poor at overnight delivery and this has created too many problems.


Can I get it Delivered by FedEx or UPS?

Sorry - we no longer offer UPS or FedEx shipping.

USPS has not been perfect but surprisingly on average they have given our customers the best results.


How many Bands of Tone Control is most Popular with Players?

The 4 band is the most popular option.


Why do I need a 4 Band Tone Control?

Four bands of tone control makes it easier to dial in the tone you want quickly but if you think a 2 or 3 band will work better for you then select those options.


Why does a different number of Tone Control Bands change the price?

Each configuration is a unique circuit board - designed to optimize the performance for a specific configuration.

The increased number of tone control bands requires more parts - so we charge a minor difference in price to account for the extra cost to build the preamp.


What is the difference between a Pan, Blend and Balance Control?

They are the same thing.


How does a Passive Balance compare to an Active Balance?

Passive balance is traditional (and lower cost) but lacks the note definition and control of an active mixing system.

Active mixing is not new - it has been used for a very long time in all kinds of critical music applications during studio recordings.


Does the Balance control have a Center Detent?

Yes - in the detent position the 2 pickups are mixed into the output equally - note, this is after the gain adjustments.


Do the Tone Controls have a Center Detent?

Yes - the frequency response is flat in the detents.


Will it work with a Wood Top?

Probably the wood top must be thin enough that a 10mm threaded shaft length on the pot will work.

Note this is the standard to long threaded guitar pots.


Will it work with a Pick Guard Top?

Yes - you may want to double nut the controls to move them down to a reasonable height.


What size would the holes need to be to add controls?

The single controls need a 7 mm hole - the stacks need a 9 mm hole.


What size would the holes need to be to add the LED?

The LED battery meter requires a 3 mm hole.

The most common place to install the LED is on the electronic cover on the back of the bass.

If you want to add the LED to a wood top then you can back drill the led with a larger hole or

you can only use a small through hole (say 1 mm) to let the light out and use a 3 mm hole on the inside of the cavity to hold the LED - this way the LED hole is almost invisible.


Can I get it with a different color of knob set?

We offer Chrome, Gold, and Black.


Can I get it with a different style of knob?

No - we do not have other knobs but you can use knobs from other suppliers.

The singles and tops of stacks are 6mm shafts.

The bottoms of stacks are 8mm shafts.

All shafts are round holes - so a set screw is required to hold the knob on.


How long does the Battery last?

A high quality 9 volt battery will last about 250 hours plugged into most bass amps.

If you are plugged into a lower ohm load - most common is directly into a  line level recording interface - then the preamp will need more power to drive the output signal to full frequency response so your battery will have a shorter life but you are getting a higher quality recording so not a bad trade-off.


Do I need to put in a Battery Box?

No - Normally the battery can fit in the electronics cavity.


Can I hook it up to my Battery Box?


Unsolder the wires from our battery clip and move the red (+) and black (-) connections on your battery box.

Insulate the wire joints when you are done.

A 9 or 18 volt battery box system can be used, the sound will be the same.


Can I get it with a Long Threaded Body Jack?

Can I get it with a Neutrik Locking Jack?

Sorry there are too many different jack types for us to supply all of them and for some types they are hard to replace.

But if you have a stereo jack (common) then you can move our wires over to your jack.

The white is the tip connection (preamp output)

The black is the ring connection (negative side of the battery which is connected to ground by the mono plug to power up the preamp)

The Grey/white wire is the ground(s).


Does 18 volts create a Higher Output Level or Help in some way?

Same output level.

If you use a LOT of tone control boost then it might help.

Most players do not need to bother with 18 volts; our electronics work great on a single battery.


Some of my other Active Basses are Louder?

Many players will own basses that have more output gain than our preamps supply but this extra gain comes at the cost of modifying the sound quality.

At reasonable volumes, a louder bass sounds better - you perceive that it has more high and low frequencies - but if you make the volume level equal, using your amp, in order to compare it to the original tone, you probably will not be very impressed by the sound quality.

We are not trying to trick you into thinking our preamp sounds better than your passive bass by just pumping up the volume, we want your bass to retain the full passive tone of the pickups but make it play better and to be easier to use on stage.

Since all commercially viable bass power amps work well with a passive jazz bass - more of these are sold than any other type of bass... your bass amplifier should have plenty of power to drive the speakers.

If your bass amp has 2 inputs - use the one for the passive input with all of our preamps.

The active input just reduces your signal to the same level as a passive bass and then uses this signal as the source for the rest of the amplifier.

If you bass amp has only one input with a gain adjustment then set it like you would for a passive bass input.


How do I make it Sound like a Passive Bass?

Tone controls in the center detents are flat.

We do not have the distortion which most preamps do so we won't mess up your tone.


Will this work with my Pedals?

Probably - most pedals are designed for passive input levels and this preamp will play nice with them.

In a very few cases some pedals may not like that we drive the cable from a lower impedance source than a passive pickup.

We drive the cable harder to avoid external noise pickup by the output cable but if this causes you issues with a pedal, which is unlikely, then email us and we will explain how to add a resistor to the output jack way to raise the output impedance.


Will the preamp produce Hum?

The preamp will not produce hum - it runs off a battery as opposed to a 50/60 cycle power line but the preamp will pass through hum collected by the pickups.

Single coil pickups will naturally hum when the levels are not equal or in the rare case that your pickups are not RWRP pickup windings.

Normally the levels will be equal in the center detent of the balance control but this can be changed when the gain adjustments are not set equal or when a pickup maker has increased the windings on a Bridge pickup to boost its lower volume up (the string movement is less at the Bridge pickup location which creates lower volume).


I will be traveling from overseas to the US for business or a vacation - can I have the preamp shipped to my hotel?

Possibly with reasonable lead time - email us with your plans - assuming someone can sign for it (most hotels will do this) then it is probably possible to work it out.

Note we are only responsible for the preamp till it gets signed for at the delivery point.


What is the Frequency Response of the 2 Band Tone Control Option?

We use shelving controls for all Treble and Bass tone controls so the specs look different than other manufacturers.

Our specified frequency point is at the 1/2 boost or cut frequency.

The 2 band tone control specs are Bass 200 Hz +/- 18 dB and Treble 2.0 KHz +/- 17.5 dB.


What is the Frequency Response of the 3 Band Tone Control Option?

The Mid Tone control spec is 500 Hz +/- 10 dB.

We use shelving controls for all Treble and Bass tone controls so the specs look different than other manufacturers.

Our frequency specified point is where the 1/2 boost or cut frequency occurs.

The 3 band tone control specs are Bass 200 Hz +/- 16 dB and Treble 2.5 KHz +/- 16.0 dB.


What is the Frequency Response of the 4 Band Tone Control Option?

The Low Mid Tone control spec is 250 Hz +/- 10 dB.

The High Mid Tone control spec is 750 Hz +/- 10 dB.

We use shelving controls for all Treble and Bass tone controls so the specs look different than other manufacturers.

Our frequency specified point is where the 1/2 boost or cut frequency occurs.

The 4 band tone control specs are Bass 180 Hz +/- 16.0 dB and Treble 3.2 KHz +/- 18.0 dB.


What is a Passive Type Tone?

A passive type tone is a high frequency roll off circuit.

It is like the 3rd control on a standard passive jazz bass.

When you max the control, all of the high frequency content is present in the output signal.

If you turn the control to the min position a bass will get very dark with little high frequency in the signal.

At in-between settings the effects are more complex.

Many players love this type of high frequency control and it is available on the side mounted jack versions of the preamp.


I can-not hear a change from the Treble Tone Control?

When I turn it up the Bass Tone Control it causes a lot of distortion?

Most likely you are testing with an inexpensive practice type amp which has an under powered amplifier and speaker - try your real bass amp setup.

If you have a tube front end (or power section) then it may be it's time to replace the tube(s).

If you are using a very large speaker with no midrange or tweeter then you will not get a lot of Treble response. In many cases you can turn the tweeter or midrange speaker volumes up on the speaker's crossover circuit.

A few pickups have very little treble signal in their response - they tend to be over-wound versions - if you have this type of pickup it will never get very bright but this is a trade off in your pickup design.


Are these Built in the USA?

Depends on if you are in the camp of the lawyers from California who are suing manufacturers in the music industry for stating things are "Made in the USA" when every subpart was not made here.

News flash - by this definition NOTHING with electronics in it is Made in the USA - no fighter jets or other military items - no cars - none of it is Made in the USA.

We designed all the circuits which are unique and please see the link below to decide for yourself where it was made

Video of how we build our products in Oregon, USA.


Can you build a preamp with a different Tone Control Frequency Response?

Sorry - we do not make custom modifications to the designs.


I want to use it with a power source from my amplifier?

It's possible assuming your have modified your amplifier or have one with an internal power supply to the ring of a stereo cable.

Rewire the output jack as follows - red goes to the ring connection where black is today - use a stereo cable from your bass to the amplifier.


I have Active EMGs and seem to be getting some Distortion?

Make sure you have the EMGs hooked up correctly to the battery (red to red off battery jack) and that the EMG ground goes to the ring on the jack where black off the battery is connected.

Some older EMGs have very hot outputs - you may need to divide down the inputs to a more reasonable level - email


I have a lot Distortion?

You may have a very dead battery - replace it first.


Look at the Green/white wire - it should never electrically connect to ground.

If you have pickup wires connected the the Green/white wires then the connection to ground may occurring on the pickup part of the wiring.

Remove this connection to ground and the issue will go away but you may need to change the battery as excess power was being pulled due to the incorrect wiring connection.


I have a very scratch pots?

You have the pickup commons connected to ground without a coupling cap.

You can move the pickup common to Green/white wire or add a coupling cap to the pickup hots.


Pop when string touches the pickup pole pieces?

The pickup common is electrically connected to the pole pieces due to your wiring to the pickup or the pickups internal design.

Most often a pickup will have a unique wire to ground the pole pieces and this wire should be disconnected from the pickup common and separately connected to ground.

For example Delano pickups makes 2 versions of each pickup - with and without a separated pickup ground wire (for example they have 2 wire and 3 wire jazz pickups - the 3 wire versions have separated pole piece grounds but are otherwise identical).

If you can not rewire the pickup then you will have to clean the pickup common and pole piece parts connected to ground.

Remove all connections to Green/white

Use coupling caps to connect to the pickup hots.


I Lose Volume and it sounds tinny when the Balance is in the Center ?

Your pickups are out of phase - invert the pickups hot and common wires to 1 and only 1 of the pickups.

Note if you have two neck or bridge pickups as opposed to a pair then you will probably have odd looking wire colors when the connections are correctly phased and they will not hum cancel if single coils when the balance is centered.


My Battery Died Overnight?

This normally means the cable was left in the jack - while the cable is in the jack the preamp is powered up - so remove the cable when you are done playing.


In a few rare cases - the jack parts were touching conductive paint of foil in a cavity and keeping it powered up - to fix add insulator in-between the jack parts and wall.


When I first insert the cord plug into the Jack it has a Loud POP?

Almost all preamps internal to a bass use a stereo jack to control the battery power.

The ring on the stereo jack touches the shaft of a mono plug which grounds the negative side of the battery and powers up the preamp.

While you were inserting the plug into the jack - the end of the cable hits the ring terminal which causes the loud pop.

Professional players get in the habit of pulling the other end of the cable slightly out of their amp jack when inserting the cable into the bass which stops the popping.


The Preamp is new and it never powered up when I Inserted the Cord?

We have tested the preamps 2 independent times before it shipped - so let's look for simple situations to correct.

Most common is a bad battery, either it is very weak or completely dead.

Not getting the battery snap connected to the battery - make sure you have a good connection to both connections on the top of the battery.

Using a stereo line cord instead of a mono guitar cable - you must use a mono cord or the preamp will not power up.

Not inserting the cord far enough into the jack - the plug must go all the way into the connector.

Using a cord where the size of the plug shaft is too small to make a good electrical connection.


The Preamp works but the LED Battery Meter does not flash when I Inserted the Cord?

1) Check the wiring.

2) Check that your battery is actually good.

3) Make sure you are using a mono cable to the power amp.

4) Make sure that the amp cable is plugged all the way into the output connector.


 Assuming the above are all correct then the most likely problem is the preamp is permanently powered up.

1) Check that the output jack is a stereo jack, and the Grey/White wire for the preamp and LED Battery Meter goes to the body terminal, the negative side of the battery goes to the ring terminal.

2) With a DVM in resistance mode, remove the battery and measure the resistance with the plug out of the jack from the ring to the body terminal - it must be infinite.

3) Insert the cable plug into the jack and verify the resistance is < 1 ohm.

4) Reconnect the batteries to the preamp and verify the voltages with a DVM in DC voltage mode. The battery voltage must be > 7V but should be 9V or more.

5) With a DVM in DC voltage mode, remove the cable plug, wait 30 s.

6) Measure the voltage from Red to Ground at the jack - it should be 0 volts.

7) Insert a mono cord plug - measure the voltage from Red to Ground - it should be the battery voltage.



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  Audere Audio

  4909 S Coast Hwy, STE 295

  South Beach, OR. 97366

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Classic Preamp Series

Frequently Asked Questions