Not just an replacement, but an improvement!

The 274A is a full wave rectifier, and a full equivalent to  the original  Western Electric historic 274A.  It features a series connected filament for the  two diodes.  The series connection  makes the middle of the filamants to be virtually grounded, when  using a filament supply winding with a center tap. This tube is designed to supply 140mA with a normal C-L-C filter.   This tube is designed specially for Audio purposes, and is optimized for use with a small size first capacitor. With this tube, you will have only normal rectification current  flowing in the rectifier circuit, and no heavy current spikes.  This will result in less hum radiation into of the preamplifier, an improved sound compared to low impedance rectifier tubes for industry applications,  or solid state rectifiers.

• Hard metal filaments (Note1), series connected.
• Two extra large getters 
• Each tube  is numbered, inside the bulb  with a metal Tag
• Hand blown, Globe shaped glass
• Two extra large getters, flashing the complete tube bottem. 
• These tubes are shipped in a high quality dual box
• Tube pinting with real gold (metal),  red color is burned into the glass 
• Machined, solid tube base pins for highest contact precision. Ideal for the YAMAMOTO tube sockets. 
• Gold plated pins,  black ceramic socket.  (White bottem)

• See: CIRCUIT DIAGRAM 
• See: Note 2

Note 1)  Hard-metal filaments prevent filament breakage with DHT Tubes.  This material has a higher melting point than the classical nickel wires. 

Note 2)  To prevent large charge current peaks, the first capacitor (C1) should NOT  be larger than  4uF.   If the input capacitor is too large,  this will result in  heavy AC charge current through this capacitor. This is not good for the rectifier tube, and  also the  AC capacitor current peaks may cause hum radiation into the pre-amplifier.  With the given C-L-C values in  table, the rectifier circuit will work  without any trace of hum.  For ultimate filtering,  with oversized components, you  will have best  results by increasing the choke.  Do not oversize capacitor C1, this  will not give better  results. SEE:  CIRCUIT DIAGRAM 

Note 3) Short circuite impulse test:   This test should be done only once, during tube activation. Do not repeat this test.