Decware Zen Taboo Owner's Manual

The Zen Taboo Stereo Amplifier

Owner’s Manual MODEL TABOO

DECWARE / High Fidelity Engineering Co.

309-671-2428 Fax [phone] e-mail: [e-mail]

1202 N.E. Adams Street Peoria IL 61603 USA

www.decware.com

GETTING STARTED

TUBES

Your amp comes with premium tubes. The output tubes are made in the St. Petersburg,
Russia factory previously known as Svetlana. These special tubes were originally designed
for video applications in the Russian military. Because of this, they have much wider band­width than common audio tubes. The output tubes that come with your amplifier are fac­tory matched and should last between 6 months and 2 years depending on how many
hours the amp is used.

The input tube (smallest one) is typically a 12AX7. If you run a preamp in front of your
Taboo you can also try 12AT7 and 12AU7. Both of these alternates have less gain then the
12AX7 and will therefore require more gain from your preamp.

Any 5Y3GT rectifier (largest tube) will work. Alternately you can experiment with 5AR4
and 5U4 type rectifiers (or compatible models) however you will probably find the best
sound comes from the 5Y3GT that we ship with the amp.

The popular 6BQ5/EL84 output tubes can be used in place of the SV83/6P15P output tubes
as a direct plug-in replacement. In the Taboo, these tubes have a bit more spank, while
the SV83/6P15P tubes tend to have more tone.

Look at the photo on the front of this manual to see which tubes go where.

Now that you know which tubes do what, carefully install them into the amplifier. The rec­tifier (5Y3GT) should last for many years. This amplifier was biased and voiced with a
5Y3GT rectifier so it is logical that it would sound best. Having said that, no harm will
come to the amplifier from using a 5AR4 or even a 5U4 rectifier.

BEFORE POWERING UP

Be sure that you always have speakers connected to this or any tube amp before turning
it on. Tube amps are typically the opposite of solid state in that you can short the speaker
wires together and nothing bad will happen.

With your speakers and line level source connected, you can turn the amplifier on by flip­ping the switch on the rear. The switch on the front is not the power switch, but rather a
signature altering switch that changes the amp from “normal” to “lucid” mode. It may be
operated in either position and can be operated on the fly while you listen.

After allowing the amplifier to warm up for a few minutes, you can slowly raise the volume
(located on the front) to the desired listening level.

DURING OPERATION

After about 30 minutes you will notice the amplifier getting warm. This is intentional, the
higher temperatures brought on by the pure class A operation push the fidelity higher.
Some areas of the chassis may be hotter than others. This is normal. However, proper
ventilation is recommended. If you operate the amplifier inside a cabinet, allow a minimum
of 4 inches on the sides, and 10 inches above if possible.

The output tubes have a glass temperature of 200 degrees centigrade by design, and you
can be assured that they will be that hot if you touch them or your cat decides to lick one.

The last heat related comment is this - turn your amp off when your not using it. Tube life
is directly tied to hours of operation so there is no point wasting it when your not listening.

INITIAL BREAK-IN EXPERIENCE

Unfortunately the esoteric parts in this amplifier need to break-in. The combination of a
fast amplifier and fresh parts can be a little rude so we will explain the process.

Specifically it is the exotic capacitors that actually require the burn-in to sound right. The
fastest way to achieve a burn-in is to play the amplifier for 5 hours and then turn it off and
let it rest for 5 hours. Once you have repeated this process 5 times your soundstage will
bloom and the focus will begin to lock into a crystal clear image.

If you listen to your amp during the burn-in process this is what you will experience: First
the amp will sound good followed by almost an immediate increase in harshness which af­ter 30 minutes will change to dullness and continue to go back and forth. During this mind
bending experience the imaging and soundstage will be unstable and somewhat restricted.
There will be moments of incredible sound during this process and equally ugly sound. You
will know when the amp is burned-in because out of nowhere some night when your listen-
ing the amp will bloom with a soundstage almost double in size and forever stay that way
in all successive listening sessions. As you amplifier ages, it will season like fine wine and
continue to do so for many years. An amplifier that is a couple years old almost always
sounds superior to a brand new one assuming both are using a fresh set of tubes.

DESIGN GOAL

The design goal behind this amplifier was simply to take our stock Zen Triode platform and
push the envelope of its design to the limit. It uses many of the same parts as found in our
other amps and is every bit the equal in fidelity. Unquestionably this single ended pentode
amplifier is completely at home in head to head comparisons with any SET (Single ended
Triode) amps including our own.

Since you only hear the weakest link in a high end audio system, you will find the quality
of your source and cables as well as your speakers to effect profound changes in the over­all fidelity of your system. This amplifier will show you the weak links in your system and
because of it’s resolution some of the weak links may come as a real surprise to you. Point
is your Taboo is not likely to ever be the weak link in your system provided you have sen­sitive speakers that don’t require gobs of power to sound good.

Like the stock Zen amp, this is intended for those who like to get lost in a huge 3-D image
and experience the emotional side of music that only this type of resolution can accurately
convey without grain or ear fatigue. It is not intended for loud playback levels, or parties.
Unless of course you have full range horn speakers around 100dB
efficiency in which case you can have both. We recommend 4 to 16 ohm speakers at least
90dB 1w/1m for most listening. Small live rooms (12 x 14 for example) or nearfield listen­ing setups can work with speakers below 90dB. On speakers that are 96dB, the Taboo
takes you to a new level approaching live music and dynamics that would make you think
you’ve got a hundreds watts or more. Always strive for more efficient speakers if you’re

going for unrestricted listening of exceptional quality.

CIRCUIT DESIGN

The Zen Taboo amp is a combination of simple yet unique circuit design, high quality parts
selected for their signature, intense quality control, and layout. The small size makes pos­sible the art of hand soldering the entire circuit with only parts leads and no hook-up wire.
The ground buss is silver and so are the cathode leads.

The power supply is significantly over sized and breaths naturally with the music while
holding steady to less than a 0.05 millivolt sag at clipping.

There are less then 11 solder nodes between the input and output jacks of this amplifier
making it around the complexity of a single Op-amp. The output transformers were me­ticulously designed and hand built in the USA for this amplifier, as is the power trans­former.

These features combine to create a unique and magical amplifier that sounds better than
anything in its power range. If you find this to be less then 100% true please return it on
the 30 day trial period.

INPUT OPTIONS

This amplifier features input jacks on the rear with a front mounted ALPs volume control so
that you can use it without a preamp. Using a good pair of interconnects directly from the
outputs of your CD player or DAC will clearly demonstrate how bad most preamps really
are. That said, the Taboo has a higher then normal input sensitivity of around 3 volts.
That means that without a preamp you will not be able to clip the amp, even at full vol­ume. A good preamp with gain (such as our SE84CSP ) will add weight, body, dynamics,
and size to the sound of this amplifier and is often recommended.

BIASING

One of the hallmarks of this amplifier like the stock Zen amp, is the fact that it is self­biasing. That means you never have to adjust the bias, even when you change to different
tubes such as from an EL84 to an SV83. This eliminates the headache of owning tube gear
resulting in a product that never requires maintenance or tune-ups. Just replace the out­put tubes every year or so and that’s it. This also makes it possible to run un-matched
output tubes with no sonic side effects other then the obvious fact one tube will be slightly
stronger then the other - or put another way, one channel would clip slightly before the
other. (If this ever became an issue it is a strong indicator that you need more efficient
speakers or higher power amplifiers for your listening habits.)

LISTENING

There is no doubt you may find the fidelity of this amplifier superior to almost anything
within its power range and everything above it’s power range regardless of price. It really
is that good. Having said that with great confidence we find many people do not experi­ence the full potential of its spell casting abilities due to weak links in their system - usu­ally these weak links are speaker and room related but don’t be surprised if it’s your
source!

Because of the incredible resolution of this amplifier, you will find it easier to adjust your
speakers properly for best imaging because there is no time smearing, or filtering common
in most amps. Perhaps the amps strongest weapon is the huge soundstage it casts. To
hear music get completely holographic, you need to work on room acoustics and speaker
placement. Do not put your speakers near any walls, especially the front wall. Do not put
reflective surfaces (TV SETS) between your speakers. Pull them out into the room several
feet from the front wall and toe them in to create a triangle with your listening chair.

Take the opportunity to try different speakers whenever possible, you may find that now
with a good amp the differences in speakers will be even more profound. Since you always
hear ONLY the weakest link in your system, you will want to pay attention to cables and
speaker wires as they too will make far more difference than you think.

Power conditioners (real ones) are recommended. Clean power is essential. To find out
what clean power sounds like, listen to the amp at 2:00 a.m. when there are fewer nasty
harmonics in the power line. Once you have your first out of body experience during a late
night listening session we have a forum on our web site where you can share your experi­ences with other Zen Taboo owners and get tips on set-ups that really work well.

LUCID MODE

Lucid mode is an alternate signature that your Taboo can have at the flip of a switch while
you listen. The switch located on the front of the amplifier is in “standard mode” when it is
towards the front of the amp, and in “lucid mode” when it switched towards the back of the
amp. Lucid mode is part of this amplifiers very original output circuit design. It adds pres­ence and decay when compared to “standard mode”. This can go a long way to making
digital sources sound more listenable. To become familiar with “lucid mode” you should
flip the switch with each recording you listen to. As you do so, you will find that the effects
of “lucid mode” act on some recordings more then others. With a little listening time under
your belt, you will know based on preference which mode to use every time you fire up
your amplifier.

FEEDBACK CONTROLS

The Taboo has stereo feedback controls that create the ability to make fine adjustments to
the feedback taper on each channel. All the way to left is more feedback, all the way to
the right is less feedback. The control as it is being swept from one extreme to the other
adjusts the taper or frequencies that feedback are applied to. The controls are generally
found to sound best just left of center, however you may find the best sound to be hiding
anywhere in the controls range, so experimenting with it frequently is advantageous.

USING YOUR AMP AS A MONO BLOCK

The Zen Taboo was designed specifically as a stereo amplifier. Even though our original
Zen Triode amps can be run mono by bridging the outputs, this amplifier has a bit more
power so bridging should not be required. If you find that this amp is not enough power
and are unwilling to find more efficient speakers, we have it’s big brother available in a
push-pull circuit using KT88’s that would have the power your after.

WARRANTY

Your new amplifier is built so well that during research and development we took one and
dropped it from a height of 15 feet onto concrete 40 times, followed by putting it into a
paint shaker for 2 hours. Badly beaten, the amp was retubed and played perfectly with
ZERO internal damage. This is why we offer you a lifetime warranty on parts and labor
to the original owner. You have purchased a 100% hand made amplifier with some of the
highest build quality in the industry. It was designed to give 30 years of trouble free ser­vice. Enjoy.

SERVICE

This amplifier operates at 450 volts DC and should not have the bottom cover removed ex­cept by qualified service personal. No user serviceable parts are inside. Output tubes
should be replaced after 3000 hours of use. The input tube should be checked each time
the output tubes are replaced. Input tubes can range from 3000 ~ 8000 hours of use or
more before replacement. The rectifier tube typically lasts for many years and only need
be checked periodically.

If your amplifier develops a problem the first step is to call us and talk to Steve directly.
90% of all problems they might develop over time are found to be a bad tube(s) or faulty/
intermittent ground in an interconnect or power cable causing ground loop hum.

There is a paper on the website in the articles section that was written as a guide for trou­bleshooting hum problems. If you experience any hum when using this amplifier you
should consult the web site and go through the step-by-step diagnosis for isolate the
source. The Taboo has on average 0.6 milivolts of AC hum which is staggeringly low for
tube gear. You shouldn’t be able to hear any hum, ever.

Should your amp require service for any reason please return it to Decware so we can dis­cover the cause of the failure and make the proper repairs.

Always pack the amp using the original shipping carton of something of equal effective­ness. If you need a new carton please call us and order one. Don’t take chances with
shipping damage. All shippers will TRY TO BREAK THE AMP, it’s just a fact of life.

Repairs when needed are typically complete within 72 hours of the amps arrival at
Decware. Most are done the same day.

ADDITIONAL INFORMATION

Specifications and design notes can be found at our web site: www.decware.com

Manufactured by

DECWARE / HIGH FIDEILTY ENGINEERING CO.

1202 N.E. Adams Street, Peoria IL 61603 USA

[phone] or fax [phone]