Decware SE-84-CS Owners manual

DECWARE

Select Zen Triode Stereo Amplifier

Model SE84CS

DECWARE / High Fidelity Engineering Co.

1202 N.E. Adams Street Peoria IL 61603 USA

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

www.decware.com (C)2000 All Rights Reserved

DECWARE

Owner’s Manual

GETTING STARTED

Save your shipping carton. It has been designed to withstand the abuse of UPS. We tested it by
dropping amps off the roof of our facility onto the parking lot. The fact that your amp is perfect
condition is testimony that shipping carton works. Should you ever need to send your amp back
for warranty repairs, or trade it in on something else, you will NEED the original shipping carton.

TUBES

Your amp comes with premium tubes. The output tubes are from SVETLANA and are made in
St. Petersburg, Russia. 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 4 months and 2 years depending on the sensitivity of your speakers and how often you
clip the amp. The input tube (smallest one) can be either a 6N1P, a 6DJ8, or a 6922. Each ef­fect a different signature so it is nice to collect all three for experimentation. Any 5U4 rectifier will
work (largest tube) and the popular 6BQ5/EL84 output tubes can be used in place of the SV83
output tubes as a direct plug-in replacement.

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
(5U4) should last for many years. If your amplifier was shipped with a Chinese 5U4 you will no­tice a small flash inside the tube when you first turn on the amp, and you will hear a mechanical
vibration inside the tube as it resonates with 60 cycle ac. This causes no harm to the amplifier
and is no cause for alarm. Most 5U4 tubes (especially new old stock USA made tubes) do not
do this, but of the current manufactured 5U4 tubes available, we feel the Chinese is one of the
better sounding.

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.

DECWARE / High Fidelity Engineering Co.

1202 N.E. Adams Street Peoria IL 61603 USA

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

www.decware.com (C)2000 All Rights Reserved

DECWARE

Owner’s Manual

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 bias adjustment
for the input tube. It may be operated in either position, but should be changed only when the
amplifier is turned off.

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

DURING OPERATION

After about 30 minutes you will notice the amplifier getting very 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.

This is important to consider with the rather extremist option of front input jacks. Naturally if you
use these jacks, routing of your interconnects is important. If they touch the output tubes, they
will surely melt, unless of course you have our silver/Teflon cables that will not melt.

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 SELECT amplifier besides being extremely fast, also
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 at
least 5 hours.

DECWARE / High Fidelity Engineering Co.

1202 N.E. Adams Street Peoria IL 61603 USA

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

www.decware.com (C)2000 All Rights Reserved

DECWARE

Owner’s Manual

Once you have repeated this process 5 times your soundstage will bloom and the focus will 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 listening 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.

DESIGN GOAL

The design goal behind this amplifier was simply to take our stock Zen Triode amp and push the
envelope of its design to the limit. It uses all the same parts as found in our Signature Mono
Blocks (model SV83S) and is every bit the equal in fidelity when power is not an issue. Perhaps
the purist amp in the world you will likely never find it to be the weak link in your audio system.
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.

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 ohm speakers with simple
crossovers that are in excess of 90dB for most listening. This amplifier will run speakers down
to less than 1 ohm, and put out more power as it does so. Therefor you need not be concerned
about dips in your impedance curve when choosing a speaker.

DECWARE / High Fidelity Engineering Co.

1202 N.E. Adams Street Peoria IL 61603 USA

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

www.decware.com (C)2000 All Rights Reserved