zapco Z-150.4 II User manual

1
Z-II SERIES
Owner’s Manual
Before o erating the unit, lease read this manual throughly and retain it for future reference.

MISSION STATEMENT
Comm tted to Excellence
ZAPCO is dedicated to the pursuit o audio idelity. Our prime objectives are to
design and manu acture audio products o unsurpassed quality, to provide
unparalleled support and service or these products and to conduct business
in a manner that will enhance the quality o li e or all involved.
Exper ence
(Knowledge from do ng)
There is absolutely no substitute or experience; that is a simple act o li e.
Another simple act is that ZAPCO has, or over orty years, been the leader in
de ining quality standards or the car audio industry.
These years o experience have led to a thorough understanding o the
challenges that are unique to the world o car audio. ZAPCO's relentless quest
or sonic purity consistently yields imaginative designs that utilize the most
innovative technologies. The resulting products set the criteria by which all
others in the industry are judged.

1
Table of Contents
The new Zapco Z-Series Ampli iers ................................................................. 2
The re-birth o the Z-Series .................................................................... 2
Improved Circuit Board and Functionality Class AB .................................. 3
Improved Circuit Board and Functionality Class D .................................... 4
Be ore you start your Installation ................................................................... 5
Planning your Power Connections ................................................................. 6
Wire size ................................................................................................. 7
Mounting your Z-II Series Ampli ier ................................................................ 8
The Z-II Class AB SQ Competition Ampli iers .................................................. 9
Z-150.2 II Input and Controls ................................................................... 9
Z-150.4 II Input and Controls ................................................................... 10
Z-150.6 II Input and Controls ................................................................... 11
Z-150.2 II Speaker Wiring ........................................................................ 12
Z-150.4 II Speaker Wiring ........................................................................ 14
Z-150.6 II Speaker Wiring ........................................................................ 17
The Z-II Class D SQ Competition Bass Ampli iers ............................................ 20
Z-KD II Input and Controls ....................................................................... 20
Z-KD II Speaker Wiring ............................................................................ 22
Technical Speci ications ................................................................................... 24

2
The New Zapco Z-Ser es Ampl f er
Congratulations, on the purchase o your new Zapco Z-Series ampli ier. We
believe you now have the inest sound available in a car sound ampli ier, and we
think you should know a little bit about what makes this amp unique in a world
o so many so-so products.
The re-b rth of the Z-Ser es
In 2012 Zapco introduced the new Z-Series o SQ amps. These amps were not
conceived so much by our engineers, as by input rom audiophiles and car sound
anatics around the world. Starting about 2004, at Zapco training seminars in
Asia and in the EU, we began running into audiophiles who were changing
certain internal components in our ampli iers to achieve what they elt was
better quality sound.
With that in our minds, we developed the Z-Series amps with less measuring
and more listening. So or the Z-Series o Zapco ampli iers, we experimented
with internal components and new circuits to see i we could take our amps to
the next level o sound quality by investing in di erent internal components
and circuit designs, and the resulting Z-Series amps were the results o this
unique development method.
Over the last years we have developed two specialized ampli iers to take auto
sound to a di erent level. The Z-Series LX amp, the ultimate SQ amp. No controls
except gain. A pure SQ amp. We also brought out the ZSP-Series amps or the
anatics that want to play ull-volume ull-time but still get audiophile sound.
This year we stepped back and took a look at the amp that started it all. The
Z-Series ampli ier. We knew we could bring the price down, because over the
last ew years. This allowed us to build the Z-series LX and amps cost only a
little more than the original Z-Series so the prices weren't that ar apart. Now
we have brought the Z-Series into the same plant as the newer models. This
saves money!
That lowers the price, but what could we do the make it better? We saw that a
lot o the non-critical parts rom the LX and amps could used in the new Z-Series
as well. Even with some o the SQ parts we save by buying more so we can use
those in the Z-series also.

3
Bottom line, we have improved the ampli ier at the same time we brought the
price down. Who ever does that!
O course, that's just talk, but here's the bee .
For the Class AB ull range Competition Amps:
• A new TI op-amp that give the Z considerably better signal to noise ratio,
with a lower loor noise
• We used the same audiophile grade caps that we use in the LX and amps
• We bee ed up the power supply with more storage and less internal
resistance and lower inductance or higher e iciency
• We added more MOSFETS to the power supply or e iciency and current
handling
About unctionality:
• The end plates are now recessed like the LX amps or a cleaner look
• The plastic controls have been replaced by new metal pots and switches.
The new pots also have detents (like the amps) at 40ea so you can accurately
set crossovers gains identical or right and le t channels
• The new Z-II AB amps have band pass crossovers on all models so you
won't need any outboard devices to make a band pass
• x-10 the multiplier switches rom the amps are on the New Z to extend
the crossover ranges. This means Z-150.2 II can have higher requency
crossover or a dedicated tweeter amp and the Z-150.6 II can do tweeter,
midrange, and bass all with internal crossovers

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• The new Z-Series amps have the same panel mount RCA connectors as
the LX amps. Even the tightest RCA connector can't hurt them
For the Class D Competition Bass Amps:
The Z-II bass amps also get a number o improvements.
• A bee ed up power supply
• Increased power
• New high end audio caps like the SQ amps
• New TI low noise op-amps like the SQ amps
• Improved ti any style panel mount RCA connectors
• The end plates are now recessed like the LX amps or a cleaner look
• The plastic controls have been replaced by the new metal pots and
switches. The new pots also have detents (like the SP amps) at 40ea so you
can accurately set crossovers and gains identical with multiple ampli iers
So there you are! Functionality improvements to make the amps more use ul and
sound quality improvements you'd never expect rom a Class D bass amp.
Z-KD II; more use ul, better looking and even better sounding.
Class A/B amps or ull range use and Class D amps or bass. Whatever your
needs, the new Zapco Z-II Competition series ampli iers bring you better eatures,
better power, and better sound.
As we promised when we started: We will never re-paint an amp and call it a new
model. Every run o ampli iers must be better than the last or we won't make it.
We sincerely hope you enjoy your new Z-II Series ampli ier as much as we
enjoyed the time we spent developing it.

5
Before you start your nstallat on
ZAPCO highly recommends that a use or circuit breaker be placed within 18"
o the battery. Although you will add a use or use block near the ampli ier it
is still a possibility that a pinched power wire between the component use
and the battery could result in a short, or even a ire. The protection device
should be placed where it can be accessed easily and all wiring should be
routed sa ely and correctly according to the ollowing guidelines:
Do not run wiring close to hot or spinning objects.
Always use wire grommets when routing wire through the irewall or any
other metal panels.
Make sure that the potential or pinched wiring is avoided by routing all wires
away rom moving hinges and seats. This also includes brake, gas and clutch
pedals, hood and trunk hinges, etc.
Continuous exposure to excessive sound pressure levels may cause permanent
hearing loss. ZAPCO strongly advises that you use common sense when setting
volume levels. I you experience ringing in the ears, it could cause permanent
hearing damage!
When connecting our ampli iers to pre-wired stock speakers, care must be
taken that there are no common connections between le t and right speaker
wires, i.e. two or more speakers using the same ground connection (very
common in pre-85 cars), as this will cause the ampli ier to go into immediate
protection or may cause damage to the ampli ier. Output connections are not
common chassis ground. Please ollow the hookup instructions in this owner's
manual. Any questions should be directed to your local ZAPCO dealer.
Caut on: Continuous exposure to excessive sound pressure levels may cause
permanent hearing loss. ZAPCO strongly advises that you use common sense
when setting volume levels. I you experience ringing in the ears, it could
cause permanent hearing damage!

6
Plann ng your power connect ons
The power end plates o the Zapco Z-series ampli iers carry the power connections
and the Speaker connections and vary somewhat by the number o channels.
For example, the power end o the Z-150.6 II has (o course) Speaker connections
or six channels. One model, the Z-150.2 II has on-board uses, while all other
models will require and in-line use. Please ollow the rating guidelines as in the
Speci ications page at the end o this manual.
That said, the main 12-volt power input, the 12-volt turn-on wire, and the main
Ground connections are common to all models.
• The connection at the interior o the end plate is the main power input.
This must be connected the vehicle battery's positive (+) terminal, and a
main system use should be placed close to the battery
• The connection at the outside o the end plate is the main ground or negative
connection. This must be securely attached to bare metal at the vehicle rame,
or other heavy chassis component with a direct connection to the rame
Note: Seat bolts and seat belt bolts are NOT good ground po nts
• The small terminal between the main power and ground is the +12 turn-on
input and can be connected to the head unit turn-on output wire. I none
is available it can be connected to an accessory (ACC) terminal. You should
avoid using any ignition-on (IGN) wire, as they can be noisy
Note: The Z-Ser es ampl f ers have term nals that do not requ re connectors. You s mply nsert
a bare port on of w re and t ghten the connect on w th the suppl ed Hex tool. As the w re
conforms to the connector the connect on can loosen. You should re-t ghten the connect on
after about a week.
Turn-on tr gger w re
+12 volt at Baery pos ve term nal Ground to chass s

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Some words about Power and Ground
Note: The second most common cause of underperform ng ampl f ers s nsuff c ent power
current or a pour power connect on. The most common cause of underperform ng ampl f ers s
nsuff c ent ground current or a bad ground connect on.
12-volt current: Battery Power works only i it travels in a complete circuit rom
the battery positive terminal to the battery negative terminal. Main power
input, o course, is attached to the battery positive terminal. Ground current is
returned to the battery through the chassis to the point where the battery is
grounded.
The current available or your ampli ier to use to produce power will be
restricted by the smallest gauge o wire in the circuit and by the weakest physical
connection in the circuit.
W re S ze
It's o ten surprising how many people will obsess about signal wire but routinely
provide the ampli ier with only a raction o the current it needs to do its job.
The most common wire gauge used in car audio is 10-gauge, and the most
common location or ampli iers is in the trunk.
W re S z ng Chart
4 t 7 t 10 t 13 t 16 t 19 t 22 t 28 t
0-20 amps 14 12 12 10 10 888
20-35 amps 12 10 886664
35-50 amps 10 8866444
50-60 amps 88644442
65-85 amps 66442220
85 -105amps 66422220
105-125 amps 44422000
125-150 amps 22220000
Let's look at a airly small system. I you use a 50 watt/ch amp (25 amps)
or the highs and a 100 watt/ch amp (40 amps) or the woo ers, you need at
least a 4-gauge and maybe a 2-Guage wire to provide 65 amps at the trunk.
Anything less and your car won't go boom. It'll just go Blap!
Length of Run

8
Note: It takes lots of current to make lots of power!
Remember! An electrical circuit is just that... a complete circuit. For current to
travel, you must complete the circuit rom the positive terminal to the negative
terminal (which is connected to the vehicle rame). So what ever Gauge wire
you use or power (B+) you must also use or ground (B-).
Note: A 4-gauge power w re needs 4-gauge ground w re!
Use the Wire Sizing Chart! Add up the use values on the ampli ier(s) then
choose the proper size wire based on the distance rom the car battery to the
ampli ier location. Again, always use the same gauge wire or the main ground
as you do or the main power. Always make your ground as short as possible
and secure it to a clean solid sur ace, pre erably the vehicle rame.
Mount ng your Z-II Ser es ampl f er
Mounting your Zapco ampli ier is easy. Just keep in mind a ew guidelines:
• The ampli ier can be mounted in any direction, on wood, metal, or carpet
• The metal chassis o the amp can be grounded or le t isolated
• The ampli ier requires adequate ventilation. Creating power creates
heat, and cooling requires air. Position the ampli ier with su icient
surrounding area or air supply and keep the end plate and side vents
clear or internal cooling
• Keep the ampli ier out o the engine compartment or other locations
that may cause excessive heat or moisture
• Do not mount the ampli ier to a subwoo er box or other place that may
have excessive vibration
Sett ng Ga ns: Gain pots are not volume controls. Be ore you irst turn on your
system, you should make sure all gain controls are set to minimum. Gain
controls should be used only i absolutely necessary. Turning up gain controls
causes increased noise, makes distortion more likely and reduces the dynamic
range o your system. I you head unit does not have su icient output, you will
get much better results by investing in a line driver to provide more signal to
the ampli ier.

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Z-150.2 II Input Ends
The Input ends o the Z-II ampli iers is where you ind the signal input connectors
and the various controls. All the Z-II amps have the same basic unctions,
adapted slightly to it the expected use o each model.
We look irst at the stereo (2-Channel) amp. The 550 watt (Bridged @ 4Ω)
Z-150.2 II. Then we will look at the 4-Channel and 6-Channel models to see how
they adapt to multichannel con igurations.
Note: If you are us ng an amp for a band-pass m drange, the HP f lter w ll be the lowest frequency
of the band and the LP f lter w ll be the top of the band. Th s passes all the frequenc es between
them. If you reverse the f lters you w ll have no sound.
1• Right and le t RCA input connectors using
Zapco's proprietary connectors
2• To ease multi-amp installations, the amps
have pass-through RCA outputs so you can
"daisy-chain" multiple amps while only
running one ront-to-back RCA
3• Variable gain control
4• A unique eature o the crossovers is
the Multiplier X10 switch that allows accurate
requency setting by changing the crossover
range rom 15Hz~500Hz to 150Hz~5000Hz.
This is so you can use the amp ull range, as a
mid range (band-pass), or even as a tweeter amp
5• The high-pass (HP) crossover requency
selector
6• The Crossover unction switch: To the le t the
switch is in high-pass mode, in the center the
crossover is out o the signal path ( ull-range),
to the right both ilters are in the circuit so you
can band-pass. I you are using the amp or bass
the LP will be you sub crossover while HP ilter
will be a variable sub-sonic ilter as low as 15Hz
7• The low-pass (LP) requency selector
8• The X10 switch or the LP ilter
9• Variable bass boost control rom 0dB~12dB
10• Port or the optional bass control
11• The power on (green) LED and the protect
(red) LED
2 3
4
5
6
7 8
9
10
11
1

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Z-150.4 II Input Ends
The Z-150.4 II is the 4-Channel amp and has the same basic controls and eatures as
the 2-Channel amps but adapted or 4-channel use.
• The ront channels do not have a low pass ilter as they will be used either ull
range or or mids/highs or even tweeters
• The rear channels have exactly the same controls as the 2-Channel amps as
the rears will be used as ull-range or bass, depending on the application, or
even band-pass i the amp is used or tweeters (Ch1/2) and mid-range's (Ch3/4)
• The Z-150.4 II adds a 2Ch/4Ch switch so you can choose to have only the
Ch1/2 inputs eed both ront and rear
* See explanat ons of these funct ons on the prev ous sect on 2-Channel amps
1• Front (Ch1/2) RCA inputs
2• Rear (Ch2/4) RCA inputs
3• Front and rear variable gain controls
4• Front (Ch1/2) Multiplier and HPF
requency control*
5• Crossover mode select (Clone position
makes both ront and rear crossovers identical)
6• Rear (Ch3/4) HPF requency control
7• Rear crossover mode switch*
8• Rear (Ch3/4) Multiplier and LPF requency
control*
9• Variable Bass boost control
10• Port or optional dash mount bass gain
control
11• Auxiliary pass-through RCA output*
12• Power and Protect LEDs
2 3
4 1210
6 7 89 11
5
1

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Z-150.6 II Input Ends
The Z-150.6 II is the 4-Channel amp and it also has the same basic controls and
eatures as the other amps but has been adapted or 6-channel use.
• The channels 1/2 do not have a low-pass ilter as they will be used either ull
range or or mids/highs so there is only high pass here
• Channels 3/4 have high pass, ull range, and low pass positions so they can be
used or highs, or they can be band-passed or mid-range use
• Channels 5/6 do not have a crossover unction switch as they are band pass
only. They can be used a the bass section with the low-pass and a variable sub
sonic. The sub sonic (which is high-pass), however has a wide requency range
so it can be used as the bottom o a band-pass to drive mid-bass drivers, i you
have a separate sub amp
• The input mode switch lets you use 2Ch, 4Ch,o 6Ch o input, so you can
drive all the channels rom a single 2Ch stereo output rom a head unit
* See explanat ons of common funct ons on the prev ous sect ons
1• Ch1/2 and Ch3/4 RCA Inputs
2• Ch1/2 and Ch3/4 variable gain controls
3• Ch1/2 and Ch3/4 HPF requency controls
4• Ch1/2 and 3/4 crossover mode switches
5• Ch3/4 LPF requency control
6• Input mode or 2Ch, 4Ch, or 6Ch inputs
7• Port or optional dash remote
8• Ch5/6 RCA inputs
9• Ch5/6 Sub sonic (HP) requency control
10• Ch5/6 LP bass crossover requency control
11• Variable bass boost control
12• Ch5/6 variable gain control
13• Power and protect LEDs
1 2
4 1310
3 5 6 7
11
8
912

12
Speaker W r ng of the Z-II Class AB Ampl f ers
The Very Bas cs
• No speaker wires can be shorted to, or touching either ground or each other.
This will put the amp into protect and may damage the ampli ier
• When bridging the le t and right channels o any ampli ier, you use the
le t channel (Ch1) positive and the right channel (Ch2) negative, as indicated
on the chassis by the speaker terminals
Z-150.2 II Speaker W r ng
Stereo Mode
• Commonly a pair o ull range speakers with x10 swt. o (out or x1 position)
and HPF set between 70Hz~100Hz to protect the speakers rom deep bass.
• To use or tweeters put Multiplier switch to x10 (pushed in) and set HPF
between 2000Hz~5000Hz, as per the tweeter makers recommendation
• To use or midrange: Determine the range o requencies you want. Put the
LPF/BPF Multiplier switch to x10 (pushed in) and set the LPF ilter to the highest
requency you want to have. Set the HPF ilter to the lowest requency you
want to have
S ngle Channel Mode
Bridged to one voice coil using L+ and R-
• Commonly or a woo er. Set crossover mode to LPF/BPF with Multiplier to o (x1)
• Set LPF req. to woo er maker’s recommendation. Set HPF crossover req. to
20Hz to use as a sub sonic ilter

Note: Take note that 4 Ohms s the m n mum load when br dg ng, s nce each channel w ll see
only 1/2 the load (2 ohms). Do not br dge w th a 2Ω woofer
3Ch Mode
It is possible to run the 2-Channel amps in “3-channel” mode by running a pair o
speakers or the mids and highs on le t and right channels, and at the same time
run a woo er bridged between the L+ and R- terminals as shown. However, since
each channel will see 1/2 the impedance o the woo er you must use a woo er o
no less than 4Ω. The ampli ier sees impedance by requency, so you can have two
2Ω loads but you must use a passive crossover on each speaker in the three channel
mode. With the crossovers in the line, the ampli ier will always see a minimum
load o 2Ω on each channel at all requencies.
• Main speakers can be 2Ω~4Ω
• Woo er can be 4Ω~8Ω but cannot be less than 4Ω
• HP crossover can be FULL or can be HPF to be used between 15Hz and 25Hz
as sub sonic ilter
• LP crossover must be set to FULL
• All actual crossover unctions will be done by the passive crossovers in the lines
4Ω~8Ω
2Ω~4Ω
13
2Ω~4Ω
4Ω~8Ω
X-O
X-O
X-O

14
Z-150.4 II Speaker W r ng
Standard 4Ch Mode
The Z-150.4 II our channel ampli ier is virtually two 2Ch amps in one chassis and
each set o our speaker terminal can be used exactly as you would use a 2Ch
amp. The advantage o a our channel amp is primarily the saving o ace (and a
little money). Using a our channel also reduces the installation work, over installing
two 2Ch amps. This is especially so with some o the unique eatures o the
Z-Series amps.
• This is the standard hookup or ull range ront and rear speakers
• Speakers can be 2Ω~4Ω
• I the head unit has 2 sets o RCA outputs you will be able to ade ront to rear
• You don't have to use crossovers, but it's wise to use the HPF ilters set to
30Hz or a little more as a sub sonic ilter to protect the speakers. Best policy
is to check your speakers requency range. Set the sub sonic (HP) requency
just a little above to lowest o the speakers requency range. i.e. I the speakers
range is 40Hz~18,000Hz set ilter to 45Hz. The LPF switches should be in FULL
• The HPF Multiplier (x10 switch) must be in the o or x1 position

15
4Ch 2-Way Mode
With the unique eatures o the Z-Series ampli iers you can also use the Z-150.4 II
to drive a 2-way system with the ront channels or highs and the ear channels or
lows. The unique crossover will let you separate high and low like most 4Ch amps,
but with the added range provided by the multiplier (x10) switch you can actually
have a tweeter crossover as high as 5,000Hz on the ront channels. With the series'
band-pass unctions, you can have the rears play everything below the tweeters,
or you can have the rears play only midrange and use a separate amp or your
subs.
For the diagram below o an active 2-way system:
• Front (1/2) crossover is set to HPF and multiplier switch set to x10 (in).
HP requency is set to the tweeter's recommended cut-o point (usually
between 2KHz and 5KHz)
• Set the rear ilter to LPF/BPF so both the rear ilters are active
• Set the LPF/BPF multiplier switch to x10 (in) and set the requency to the
same requency that was used on the tweeter high-pass ilter
• I the lows speaker will be used as woo ers then set the rear (3/4) HPF to
around 30Hz as a sub sonic ilter
• I another amp will be used or bass and channels 3/4 will be used a midrange,
then set the rear HP ilter to the requency where the woo er will begin
operating (usually 80Hz~120Hz)

16
2-Way w/Br dged Mono Sub
A similar setup uses a pair o ull-range speakers with a mono subwoo er.
• Front ilter is set to HPF, the Multiplier is o (out), HP requency is set just
above the bottom o the ull-range speaker's requency range, where you will
also set the woo er crossover
• Set the rear Filter to LPF/BPF to have both ilters active and the multiplier to
o (x1). Set the rear LPF requency to the desired woo er crossover point
(which should match the ront high pass ilter), and set the HPF requency to
15Hz~30HZ as a sub sonic ilter
2Ch Br dged
Want more power? Instead o our channels o 165 watts, you can have two
channels o 550 watts each by bridging both ront and rear amp sections to one
speaker each.
• Speakers must be a minimum o 4Ω impedance
• Using RCA "Y" adaptors o 1 emale-to-2 male, put the le t signal RCA into
both L and R inputs o the ront channels and put the right signal RCA into
both L and R inputs o the rear channels
• Do not use the optional dash bass control as it will only work on the speaker
connected to the rear channels
2Ω~4Ω
4Ω~8Ω

Z-150.6 II Speaker W r ng
6 Ch 6 speakers
The Z-150.6 II is a 6-channel amp that can drive six speakers rom 6, 4, or 2
channels o input. Note that channels 5 and 6 are arranged top and bottom and
CH5 has + and - reversed rom the other channels.
That said:
• I you are driving ull range speakers the only control you will really need is on
Channels 1-4 are the HPF ilter to use as a sub sonic. Channels 5 and 6 are
designed or bass or mid-bass and plays rom 15Hz to 1000Hz
17
Ch. 2
Ch. 1
Ch. 3
Ch. 4 Ch. 6
Ch. 5

18
A One-Amp, Act ve 3-way System
The Z-150.6 II is a superbly versatile piece o gear. With the crossover eatures o
this amp you can run a completely active 3-way system. You can run it as Tweeter ,
midrange, bass. You can also ruin it as tweeter, band-passes mid-range, and band
passed mid-bass and then use a separate subwoo er amp. Below is an active 3-
way system using a mono bass driver.
• The Input Mode switch can be set or 2,4,or 6 channels o input, but setting
up a 3-way system is best done with a 2-channel input unless you are using a
digital processor ahead o the amp
• Ch1/2 are used or tweeters. The multiplier is set to x10 (pushed in) with the
Filter switch set to HPF. The HP requency is set to tweeter's recommended
HP range (usually between 2kHz~3kHz)
• Ch 3/4 are mid-range. The Ch3/4 Filter switch is set to LPF/BPF so both ilters
are active. The HP requency should be set to the requency that the woo er
will begin (usually between 80Hz~120Hz). The Ch 3/4 LP requency is set to
the same requency as the tweeter HP requency (usually 2kHz~3kHz) that
was set in the previous step
• Ch 5/6 are bridged or a mono woo er. Ch 5/6 always have both ilters active.
Set the LPF requency to the same requency as the Ch3/4 high pass ilter, so
the top o the woo er is the bottom o the midrange
• The bass boost should only be set a ter system is installed and you have had
a chance to listen to see i any bass boost is needed
- Speakers on channels 1~4 must be m n mum 2Ω of h gher
- The br dged woofer must be 4Ω of h gher
- You can add the opt onal dash control for the bass channels 5/6