and sold Factory Direct with a L i
f e t i m e W a r r a n t
were asked to put a headphone
jack on our Taboo amplifier
to be used with planar headphones
multiple times and since then ...
the Zen Taboo has become a popular topic
of conversation among Head-Fi users
from all over the world...
The tremendous feedback was encouraging
and a year later we re-designed the Taboo
from the ground up as a planar
headphone amplifier that could still
be used to drive speakers (instead of a
speaker amplifier that could still be used
to drive headphones).
The resulting Taboo Mk III was so good it
not only dominated the planar headphone
market for those who appreciate the
transparency of tubes, but developed a
real following among dynamic headphone
owners as well. Even one of the better
headphone manufactures in the USA is using
it as a reference to develop and test all
their new headphones.
We are now in the final chapter of the
evolution of this fine reference grade
headphone amplifier, with the release of
this new model, the Taboo Mk IV.
ANNOUNCING THE TABOO MK IV
You have to understand that what makes
a Taboo so unique is a feature
called "Lucid Mode" which makes things
An essoteric form of crossfeed, it was
originally intended to improve the imaging
of loudspeakers. As we all know crossfeed
is an essential ingredient in all great
headphone amp designs so in 2013 we added
a second "Lucid Mode" switch specifically
tuned for the 50 ohm Audeze LCD-2.
This made the Taboo a real force to reckon
with if you had LCD-2, ZMF or similar
Now Lucid Mode is masterfully redesigned
as a single variable control with
a bypass switch. You simply dial in the
amount of effect you want by ear as you
Lucid mode is a fully analog effect that
occurs naturally within the circuit. There
are no circuit chips, circuit boards, or
solid state parts anywhere inside a Taboo
to manipulate or posion the utter
transparency of the music.
mode is now fully
variable and as a result
the feature works with ALL headphones,
Planar or Dynamic!
Another exciting upgrade over the previous
Mk III model is an incredible dual volume setup
with infinitely adjustable left and right
controls. So far everyone who's tried it
is saying they can't live without it
despite being hesitent at first! Dual
controls allow you to do some very special
things that you won't want to live
The Taboo Mk IV also features an updated layout
requiring a new chassis design that
facilitates a more direct internal
layout resulting in more
breathtaking transparency through greater
Some features that were optional for an
extra cost on the Mk III are now
included. These include the popular
for running both high and low efficiency
headphones, and rather than having a HI
and LO headphone jack we added a switch so you can
listen to any headphone in either mode and
decide for yourself what sounds better.
with optional balanced XLR inputs
which have been optimized to take
advantage of the higher signal voltages
common with balanced sources. Having the
ability to run your Taboo fully balanced
would bring all the sonic advantages that
a good preamp usually adds but with
The Mk IV is now
built with only balanced outputs
and comes with a 4 pin XLR
headphone jack shown in the images
below. This is the only way the Taboo Mk
IV is available. There
is no unbalanced 1/4 headphone jack on
this machine. The Taboo is an
amplifier to own
because there is no maintenance
and no bias pots to adjust.
Tubes last a long time -
typically several years. The
chassis is build without vent
holes to let dirt and dust
contaminate the inside.
Like previous models,
you still have inputs for two sources
and speaker level outputs for
operating loudspeakers. Some hardcore
headphone enthusiasts will also use these speaker
binding posts in an unexpected way by
using the amplifiers binding posts to
further tune their headphones by
installing various size resistors.
in standard Walnut base
The Taboo Mk IV is a world class reference
headphone amplifier made in the USA
without circuit boards using only the best
audiophile grade parts and comes with a
options can be selected from within
the shopping cart.
This amplifier features a chassis
design with interchangeable solid
hardwood bases and different knobs.
Below is a stack of different wood
bases you can choose for your Taboo.
Below that, are your knob choices.
Top to Bottom: Oak,
Maple, Cherry, Black, Walnut, Black
to Right: Ebony, Gold, Black Chicken
head, Cream Chicken head, Walnut.
These and Other options can
be selected and
priced from within the SHOPPING
and are explained below.
This amplifier is
optionally available with our World
Voltage Compatible Transformers. If
you live outside the USA, simply
select your voltage when you check out
and your Taboo will be automatically
wired and tested for the correct
voltage of your country.
WOOD BASE OPTIONS
You may select
from two standard wood bases,
either Walnut or what we call
Black Figured, at no extra
cost. Optionally you can get Oak,
Cherry and Maple for a small up
charge. Custom woods are also
available, just check the box for
Custom in the shopping cart and then
let us know what kind of wood you want
in the comments section of the order
or in an email.
SIGNAL CAPACITOR OPTIONS
The amplifier comes standard with
Cryo-Treated High Temperature Beeswax
Capacitors with silver plated leads
from the USA company called Jupiter
Condenser. Alternately we have a type
II Beeswax capacitor that uses copper
foil that is claimed to be a notch
better from the same manufactuer.
The knob choices
are shown above. All are
interchangeable so should you ever
change your mind down the road,
the knobs can be changed by you.
The Taboo Mk IV
comes standard with dual RCA inputs
featuring 24k Gold Plated Teflon jacks
made in the USA. These are the ones
shown in the left picture below.
Silver RCA jacks (shown right) are
available for a slight up charge.
These may be preferred by those running
pure silver signal cables with solid
silver connectors for the simple reason
there is less dissimilar metals.
Otherwise we hear no real difference.
XLR INPUT OPTION
option will allow you to run both RCA
and fully balanced XLR inputs and
switch between the two.
a video of the inside of the Taboo Mk3
that illustrates the art of
point-to-point soldering. The
Mk4 is even better.
click image to enlarge
T U B E S
configuration uses a single input tube
of the 6922 family (such as 6N1P /
6DJ8 / 6N11 / 6N23P / 7DJ8) driving a
pair of EL84 or SV83 (6P15P-EV) output
tubes. The rectifier is a 5U4 but you
may substitute 5Y3GT, 5AR4's or the
new Valve Art 274B. You can expect
over 6000 hours of pristine fidelity
from the included 6P15P-EV tubes.
Because this amp has the Hazen Grid
Mod that activates only when SV83
(6P15P-EV) output tubes are used, we
ship the amp with the best mil spec
6P15P-EV's made. These are Russian New
Old Stock tubes with Gold grids, extra
thick glass, plated pins, and tested
in your amplifier. All tubes come with
a 90 day warranty.
DECWARE always has the best quality
hand selected replacement tubes in
stock for your Taboo.
E L F - B I A S I N G
The amplifier is self biasing so you
NEVER have to set or adjust the bias
for the output tubes. If you've ever
owned an amplifier that you had to
bias all the time you'll completely
appreciate this design. The analog
meters show you the condition of each
output tube and how well the two tubes
I D E A L
S P E A K E R S
When using loudspeakers with this
amplifier, 8 ohm speakers will play
slightly louder than 4 ohm speakers.
Desktop use works with virtually any
small monitors, larger listening rooms
are best suited with speakers that are
94dB or higher.
C A B L E S
This amplifier is so transparent that
differences between cables will now
become big differences. If you don't
have good interconnects or speaker
cables or just not sure how good yours
are... we offer reference quality cables
that will let you hear its full
potential. It is important to us that
you hear what your new amp is capable so
we offer the same silver cables that we
built and use personally
S U P P O R T
This amplifier is hand built in the USA
by DECWARE / High Fidelity Engineering
C0. It comes with a lifetime warranty to
the original owner. If you purchase one
second hand and ever have questions or
technical problems we WILL be happy to
check it out for you and service it if
needed for a very reasonable rate.
We also have a support
forum with many people who own
this amplifier who's experiences you may
The original Taboo as reviewed
on 6-Moons featured a simple
steel chassis and variable
Manufactured from 2006 to
The second model featured an
upgraded chassis, and removal
of the variable feedback
controls with the addition of
both direct and variable
/ 2009 to 2012.
The same model but with the
Hazen Grid Mod and upgraded
coupling caps. Optional
MK III / 2013 to 2016.
from the ground
up to be a
amplifier that will also
drive loudspeakers. Top plate
was changed from white
to black. Cryo treated
beeswax caps became
UFO / 2016 to 2017.
This is a MK III with updated
UFO (Ultra Fidelity Output)
Transformers and a HI and LO
gain option for better pairing
with both power hungry and
MK IV / 2017 to present.
This is a MK IV that has been
redesigned with a new layout,
cleaner signal path, and
lucid mode (cross-feed /
P E C I F I C A T I O N S
requires no adjustments or maintenance
other than changing tubes every couple
years. It is a self biasing design and
self balancing meaning even unmatched
tubes become matched when installed.
The SV83 (6P15P-EV) or EL84 output
tubes were chosen for their sound
quality over all other pentodes -
price was not a factor.
x 7.25" W x 14..75" D
Powder Coat Typewriter Finish
hardwood / user
ended Class A Pentode
volts for full output
~ 80 kHz
/ 5U4 / 5AR4 tube
or EL84 / 6BQ5
US Made UFO Transformers
circuit - never needs
resistors are precision WW/MF
by DALE, VISHAY
grade Cryo Treated Beeswax
grade 500V electrolytic
IEC connector provided with
removable power cord
watts at full power
type 24K Gold / Teflon
5-way binding posts accept 8
to original owner / 90 days on
OUTPUT @ HEADPHONE JACK.
Figures double into loudspeakers.
O L T A G E S
This amplifier comes with the option
for our World Voltage Compatible
Transformer. If selected your
amp will be automatically wired for
the correct voltage for your country
and be supplied with the correct
removable power cord.
D E S I G
N N O T E S
Some of the
original TABOO Design notes
still apply even though at the time
they were written the amplifier was
for loudspeakers only.
W N E R S M A N U A L
B R O C H U R E
this amp with a
30 day money back trial
so you can hear one
in your own home!