EML 274B
$460.00
*In stock, tested, and shipping now*
The EML 274B is part of Emission Labs mesh plate series of full wave rectifiers. Designed from the onset as the ultimate type 274, these tubes have several key features.
The first being the oversized 100% mesh anode construction. This provides an extremely low mechanical resonance. The plate area, filament design, and internal geometry are designed to provide the classic/correct type 274 dynamic characteristics.
Unique to EML is the implementation of a slow warm up filament design. This is cleverly implemented to provide a 7 second (to full output) “soft start” without affecting the tubes performance. The soft start function has several advantages including prolonging filament life.
Additionally EML uses a high quality ceramic base which is rubber isolated. This helps to minimizes chassis induced vibration.
The type 274B is ideal for medium voltage/current requirements. If you’re considering a medium power SET build, we highly recommend considering the type 274B for your power supply.
Designing tube rectified power supplies is not trivial. All aspects of the voltage source (power transformer) and load must be considered. An exotic and high performance tube such as the EML 274B will reward you with exceptional sonics and durability, when implemented correctly. Additionally, substituting rectifiers in existing circuits is not always straight forward. If you are tube rolling rectifiers it is required that the limiting values of each tube type are respected.
Jac has done an excellent job outlining many of the aspects one should consider when using tube rectifiers, directly on the factory Emission Labs 5U4G page. The data and illustrations on this page provide the framework, or lens, by which all tube rectified power supplies should be viewed. For specific data on the type 274 be sure to visit the factory 274B page as well.
If you need technical support regarding any aspect of rectifier tube usage, please reach out to us.
All Emission Labs tubes are inspected and tested in-house before shipment. All EML rectifier tubes are shipped in factory packaging.
EML 274B Short Data:
Filament = 5V (5%), 2A
Limiting Values at 350VAC
- AC input voltage = 350VRMS (per plate)
- First/Reservoir cap = 20uF
- DC output Current = 125mA
- 200Ω Raa minimum
Limiting Values above 350VAC
- AC input voltage = 660VRMS (choke), 550VRMS (Capacitor Input)
- First/Reservoir cap = 4uF
- DC output Current = 150mA (cap), 200mA (choke)
- 200Ω Raa minimum
Eurotubes is an official Emission Labs dealer. All EML tubes purchased through Eurotubes come with an automatic 1-Year (2,000hrs) warranty, and are eligible for the factory registered 5-year warranty.