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Welcome to Decware


The Zen Sarah Amp

Model SEWE300B


an anniversary grade masterpiece from Decware
starting around $4200 factory wholesale 


We designed the Zen Sarah Amplifier for the Western Electric WE300B triode.


Both are made in the USA


The Zen Sarah Amp

Model SEWE300B



Decware is a family business.  This amp was named after our daughter Sarah who is also the customer service manager at Decware and one of the main people who keep this ship afloat.  If you've called Decware you've probably talked to Sarah. Her kind and confident communication skills and good looks is reflected in this amplifier so we named it after her to have a little fun.



  • Class A Single Ended Triode using one 300B per channel.

  • Purist Design is hand built point-to-point with no circuit boards.

  • Drives speakers from 2 to 16 ohms.

  • Cold Cathode Vacuum Tube Diodes (VR tubes) filter the power for all three driver tubes.

  • No global negative feedback used or any solid state parts.  

  • 4 to 7 watts / channel depending on which VR tubes are used.

  • Designed and voiced for the Western Electric 300B Triode.

  • Voicing switch used to move presence forward or back.

  • Boutique internals including Miflex Copper Foil capacitors and F&T electrolytics.

  • Cathode biased and AC heated for foolproof operation and maximum tube safety.

  • Analogue Current meters for each 300B output tube.

  • Decware UFO wide bandwidth output transformers.

  • Dual volume controls.

  • Dual RCA inputs with selector.

  • Output speaker impedance switch for each channel - use while listening.

  • Carefully voiced preamp stage is built-in. Can be used without a preamp.



The main directive behind each Decware amplifier has always been to see 'how good can we get it to sound'!  Since we make our amplifiers here in the USA we have dreamed of being able to put modern day USA made tubes in them.  When we heard Western Electric was considering producing several common guitar amp tubes, many of which Decware amplifiers actually use, we knew the best way to fast track that effort was money.  To show our support we decided to design an amplifier for the audio tube that Western Electric does produce, which is the legendary 300B.  Decware customers have been asking for a 300B amplifier for nearly 20 years...

The end result was over a year in the making. In the spirit of this classic vintage tube and Decware in general we choose an old school design approach that supports the lifetime warranty and has the best sonics.  Things like cathode bias, AC heaters, point-to-point wiring and exotic transformers were all sound quality motivated.  A year for such a simple amp design is the result of bending the design through all the possible windows of operation across many different circuits and tubes until we heard everything that was possible and knew there wasn't anything in this category / price point  that was likely to sound better.


This amplifier has some real voicing features using simple switches and your choice of three different Voltage Regulator tubes.  Each VR tube sets the plate voltage for an input or driver tube so  that you can make the amp sound your choice of nine different ways ranging from lush to super clean.

The voicing switch for each channel took months to develop and test across a wide range of speakers.  It was primarily about imaging. In one position the amp images deeper and in the other position it has more midrange presence.  You can operate it while listening.

Different rectifier tubes also affect the overall character of the amp and all of these things come together to bring the amp through a range of being slightly lush to super neutral and from laid back to snappy.  All of this voicing can be done without rolling the 300B output tubes.  

The amp works with all 300B output tubes, but the real Western Electric 300B was the most transparent and neutral that we tested and closest to the Decware sound we all love.   Many other popular 300B tubes have been tested in this amplifier and they all sounded good -- each with its own positive contribution to the pleasing sonics of the Sarah 300B.  One of particular notice is the Cryotone 300B-WC.


Steve Deckert / DECWARE



1) Tube Regulation - shown left.

2) Cathode Bias - Best sound / no way to blow up your tubes.

3) Tube Rectification - 5U4G / 274B compatible

4) Handles low impedances well.

5) AC Heater circuit with all bias current flowing through the transformer center tap. 

6) Built-in preamp stage that is preset with the right gain structure giving the amp a better sound when no preamp is used.

1) There is a vacuum regulator tube for each of the three driver tubes in this amplifier.  They are used in series with the plates to filter the power independently for each tube.   You can use OC2, OB2 or OA2.  Each one has a different voltage drop ranging from 75 ~ 150 volts so they can be used effect a wide range of voicing.

2) Cathode Bias offers the least efficiency but the best sound with no chance of the output tubes becoming damaged from bias runaway.  Meters display the current for each tube and there is never anything to adjust.  If there is nothing to set, there is no way to set it wrong.

3) Tube Rectification - This is done solely for sound.  The alternative would be solid state diodes. Changing the rectifier tube has an overall effect on every characteristic of the amps sound.  Some make the amp sound softer, some firm things up to make it harder, some fall in between.

4) 4 ohm speakers are no issue with this amplifier and it even performs reasonably well at 2 ohms.  There is a high and low switch for impedance on each channel.  For 8 and 16 ohm speakers simply adjust the switch to the high setting.  The ability to perform into low impedances aka 'difficult to drive loads' comes with all Decware designs.  It is in part from using higher than normal primary impedances in our transformers so that when the output tubes see the reflected impedance drop they put out more power instead of less.  Also the higher winding ratios and thinner wire needed to accomplish this higher impedance gives the top end more air and detail.

5) AC heaters are simple and claimed by many to be the better sounding method vs. DC.  In the Western Electric data sheets it suggests that AC heaters can also favor longer tube life.  The downfall to this approach is that many designs you see draw current through the hum balance pot which is certainly not ideal to have in a signal path.  We draw all the current through the center taps of the transformer so that none of the audio signal is dependent on the quality of the hum balance pot.  Then we use the best hum balance pot we can -- just because.

6) Completely unnecessary is the added preamp stage.  But it was done because when you add a preamp to a Decware amplifier, it always makes the source sound better.  Plus you can turn the amplifier down and the preamp up resulting in a more dynamic presentation.  We call it gain structuring.  There are only two problems with this -- 1) a good preamp with cables and cords will add thousands to the cost of your amp.  2) even with a good preamp setting the gain structure to it's best possible point will escape at least 50% of users.   We took care of this, and left nothing to chance and no way to set it wrong because it is built into the amp and pre adjusted.