Ray Tubes SELECT 5U4
The 5U4 is a common full-wave rectifier tube used in power supplies to convert alternating current to direct current in. Its twin-diode design uses a shared cathode
and two anodes to convert both halves of the AC cycle.
Rectifiers like the 5U4 are sometimes overlooked by audiophiles, but like power and signal tubes, they can greatly influence the sound of a tube amplifier.
Product Highlights
The Ray Tubes SELECT Collection offers the best tubes youʼll ever need. It goes above and beyond the baseline to bring out the best in all your favourites.
● Designed and manufactured by a team with decades of experience
● Hand-selected by engineers—only the top tubes make the cut
● Substantially more consistent performance than New Old Stock
● Unlike NOS and most other new production, covered by the Ray Tubes
One Year Warranty
Sound Characteristics
The SELECT 5U4 helps create a sonic profile that is smooth on top, full through the midrange, and grounded in natural, unforced bass. Its contribution is subtle but essential, enhancing the musicality, depth, and coherence of any tube-based system.
● The bass is characterized by composure and textural integrity, with
excellent rhythm stability integrating seamlessly into the soundstage.
● The midrange frequencies impart a sense of richness and organic flow.
The SELECT 5U4ʼs inherent smoothness allows instruments like piano,
guitar, and saxophone to show their warmth and clarity.
● The treble performance is smooth and refined, reducing the grain and
edginess often associated with more aggressive rectifiers.
Our Quality Control
Our Quality Control Each tube undergoes a seven-step quality control process, including a 24-hour burn-in period, stress tests to minimize microphonics, and critical parameters that are carefully measured to ensure consistency and accurate matching. Finally, sound engineers assess each tube under real-world listening conditions.
By the end of the quality control process, only 5% of tubes commissioned for production meet Ray Tubesʼ standards.
Our Warranty
Books have been written about the countless ways vacuum tubes can and do fail. With most manufacturers, and all New Old Stock, a tube failure leaves the user high and dry. Ray Tubes is different. All Ray Tubes products are backed by the Ray Tubes One Year Warranty, which covers manufacturing defects for twelve months from the date of purchase.
SELECT 5U4 Specifications
|
Specification |
Value |
|
Tube Socket |
4-pin |
|
Filament (Heater) Ratings |
Filament Voltage: 5V |
|
Maximum Ratings |
Peak Inverse Plate Voltage: 1550 V |
|
Absolute Maximum Ratings |
Peak Reverse Plate Voltage: 1500 V |
| Recommended Operating Conditions With Capacitor Input Filter (for two typical ranges A, B) |
|
|
Value |
|
AC RMS Voltage per Plate: |
A: 300V B: 450V |
|
Transformer Winding Resistance*: |
A: 35Ω B: 85Ω |
|
Input Filter Capacitance (Max): |
A: 40 μF B: 40 μF |
| DC Output Current**: |
A: 245mA B: 220mA |
|
DC Output Voltage**: |
A: 290V B: 470V |
*per plate winding resistance of the power transformer
**assumes capacitor input filter configured with stated load
Recommended Operating Conditions With Choke Input Filter
|
AC RMS Voltage per Plate: |
500 V |
|
Input Choke Inductance: |
10H |
|
DC Output Current: |
225 mA |
|
DC Output Voltage: |
440 V |
ThomasAndStereo
Ray Tubes Select 5U4
