BTA40 20W Single Ended Tube Amplifier

 This is the 805A tube.
This giant tube is 8" tall.
The BTA40 monoblock amp has 1 of these. 
We will show the BTA40 amp at the California Audio Show, July 2019

One 805A big tube in SE configuration
 20WRMS, Class A.
Voltage gain 36dB
8 Ohm load
RCA input
5-Way binding posts output
Internal universal power supply
Solid hardwood base
Dimensions of base12" x 20" x 4" . 
Weight   20 lbs

This monoblock amp uses one 805A tube in single ended configuration. The driver for the grid is a solid state DC coupled amplifier. The unit uses an internal universal 100V..240V 24VDC power supply. An internal regulator and voltage converter provides the 10VDC,3A for the filament and the 400VDC,200mA plate voltage.  In order to fit in the low profile base the BTA40 has 3 smaller output transformers connected in series instead of one big transformer.   Because the BTA40 runs off a 24VDC power supply internally it can also be powered by an external 24V DC power supply (optional). Normally used in pairs, the BTA40 is also available in singles. The solid hardwood base is available in several selected woods. We normally use cherry wood but we can use your own choice of wood on a custom basis. Balanced input with XLR connector is available as an option.

Internal view of the BTA40 power amplifier.

Rear panel view of the BTA40 amplifier.