FAQ - Pickups
Why does using different
pickups change the sound so much with this preamp?
How does using fewer windings change the sound?
How does the type of volume control setting change the sound?
How does the type of balance controls change the sound?
How many wires are typically used and what do they do?
What type of wire should be connected to the pickups?
Which is better series or parallel connected coils?
Can I use a pickup coil selection switch?
What is the effect of hand wound or scatter wound coils?
What effect does the different type of magnets create?
- Why does using
different pickups change the sound so much with this preamp?
- The Audere preamp interacts with pickup's design more strongly
than your traditional passive bass or other preamps because:
1) We have designed the Audere preamp systems to insure the maxim transparency/accuracy
in the signal capture. To achieve this goal we have selected some uncommon structures
like DC coupling the pickups to the preamp and at multiple points
in the design have selected significantly more expensive components
(often 10x typical) to insure that we are
giving you the most accurate view of what is being captured by the
2) The different Z-Mode settings are changing the loading on the
pickups which interacts with the design of the pickups.
Variation in the pickup's design and how the pickup's
magnetic field interacts with the string's vibration is
what causes the sound change
as the loading on the pickup is changing. The Z-Mode changes are
more fundamental than the simple Eq variations which is typically
available in preamps.
The Z-Mode switch makes it easy to extend your sonic palette, extracted
new organic and useful sound from the pickups. Most players
also appreciate the increased transparency and hearing the true
of their music revealed. But if there is a weakness within the pickup
system then the increased transparency will make this more self evident.
However do not assume price of a pickup is directly related to quality.
The Fender Squier line uses low cost pickups but the Duncan Designed Jazz pickups, for example,
are really nice traditional jazz pickups.
- How does using fewer windings
change the sound?
- Several pickup manufacturers have created pickups with a lower
number of turns than a classic Fender type pickup. They
often claim the advantage of this type of pickup design is more of
the high frequencies are
reproduced. This statement is correct for a passive bass
but is not significant for a bass that contains a preamp. To understand
why we will look at each case separately.
If the bass does not have a preamp then the pickup is the only energy
source available to drive the capacitance of the cable.
Above some frequency point the pickup will not have enough energy
to drive the
cable with a flat response; the combination of the pickup's internal
capacitance and the cable's capacitance will start attenuating the
signal level. The longer the cable, the more capacitance to be driven,
the lower the frequency point where attenuation starts.
If a bass contains a preamp, it provides the energy
to drive the cable. Which, for most pickups, plays a more significant
role in determining the high frequency response and the attenuation
point. Since the typical preamp uses a greater force
to drive the cable capacitance, the frequency response
of the system is not significantly impacted by the cable's capacitance.
Given the sound trade offs we prefer a pickup design with a standard to increased number of wire wraps.
- How does
the type of volume control setting change the sound?
- Ignoring the obvious signal level...
In a passive bass, if the volume control's level is
reduced then the high frequency response
drops at an even greater rate. The control reduces the volume
by dividing the signal which also increases the resistance, which
in turn decreases the energy available to drive the cable, and limits
the high frequency level the cable can be driven to.
In an active bass, the frequency at
which the roll off starts may or may not be affected by the volume
control level. It is common for manufacturers to put the volume control
after the preamp electronics. In that position the volume
control will limit the current which is available to
drive the capacitance of the cable when the volume level is reduced.
Audere preamps use a buffer after the volume control(s) except when the user
selects a system with an active/passive switch in the Pro Z preamps series. This
removes the impact of the volume controls resistance variation.
- How does
the type of balance controls change the sound of pickups?
- Ignoring the obvious mixing of the 2 pickup signals...
In a passive bass, the style of balance pot will also change the
frequency at which the signal attenuation starts.
The most common passive balance pots
are made with 2 audio taper pots - 1 right handed - 1 left handed.
In the center both pots are attenuating the signal mixed together.
The effective resistance in between the pickups and the output
is set by the combination of these 2 pots resistances. This combined
resistance will also reduce the frequency at which the passive
response will roll off as it attempts to drive the cable (see above).
With a 100% 'ON' balance pot - the 2 pots have a linear taper and
they are both full on when the pot is at center.
One is still right handed and the 2nd is left handed. In the center
both pots are wiring the 2 pickups
together and there is no extra source resistance to reduce the
roll off frequency. This is why some players prefer this type of
balance control on their passive basses.
In the Audere preamps, we buffer both pickups independently before
they are mixed together; this is true whether it has
2 volume controls or a balance control. Either
way you will get the full natural response of the pickups.
- How many
wires are typically used and what do they do?
- Ideally for a single coil pickup you will have 3 wires
Hot - black,
Common - white,
A dual coil would add
Hot - red
Common - green
Often the shield wire is deleted and some manufacturers use different color schemes.
- What type of wire should be
connected to the pickups?
- The wire type is not especially critical in this application since
the resistance is not significant. The capacitance and inductance
is limited by the short wire run length. The best wiring would include
a conductive shield with a drain wire. The insulation should not
easily "cold flow" (move around under pressure) since it is typically
located under the pickups and you can not see what is pushing against
the insulation. Any high quality multi-strand
wire can be used. I would recommend a wire size around 24 AWG for
easy of handling.
is better Series or Parallel connected coils?
- In a passive bass putting the 2 coils in Parallel will create more
drive current so you will get more of the high frequency response
at the end of the cable but this also changes the response of the
pickup to the strings vibrations. Even
with a passive bass most players seem to prefer the sound of
Series connected coils with a short cable.
In active basses the Series combination is most often selected.
When using an Audere
preamp the Series connection will provide a larger sound difference
when switching from
the High Z-Mode to the Mid Z-Mode.
If you want the maximum flexibility then you might consider adding
a switch (next topic) to vary the pickup's coil wiring.
- Can I use a pickup coil
- Yes - follow the instructions or wiring diagram that came from
your pickup manufacturer but use the Audere white wire with the
green stripe in place of all ground connections. Do not connect
the green stripped wire to ground! We recommend a single/series/parallel
switch which can be implemented with a DPDT On-On-On type of switch.
Having a separate switch for each pickup is even better...
With the Audere preamp - the Low Z-Mode output level will change as you change
from series to parallel mode (the degree of
change will depend on your pickups) . The parallel mode will be
louder in Low Z-Mode so be sure to consider all of your pickup coil combinations when
you adjust the Low Z-Mode gain during installation.
- What is
the effect of hand wound or scatter wound coils?
- This is a complex subject.
The hand wound coils when
compared to uniform machine wound coils can have a different response
across the frequency band depending on what path around the coil
the wire actual took during the winding process.
When combined with an Audere preamp you will hear more subtle
response effects between different pickups than you will with either
a passive bass or with most other preamps.
The High Z-Mode peaked frequency will be reduced by the
hand winding assuming you are comparing it to a coil
with an equal number of turns which is uniformly machine wound.
effect does the different type of magnets create?
- This is a very complex subject... Typical differences include:
1) How strong the output is, which may interact with a non-linear amplifier
in the signal path like any tube stage.
2) The damping rate of the strings' vibrations, especially in the Low Z-Mode.
Stronger magnets will dampen the high frequency vibrations faster.
3) Any non uniformity to the magnets shape (like a sharp edge around the
pole pieces) will create a non-uniform magnetic field for the
string's motion path to interact with.
4) The Length and Diameter of the magnets will effect the shape
of the magnetic field in the area of the strings.
There are lots of other differences but these are some of the larger