If you are looking for the best 5Y3 rectifier tube, you can find all the essential information in this article.
5Y3 is a ‘full wave’ rectifier tube that works with a power transformer to transform AC voltage to DC. Radio Corporation of America (RCA) introduced this medium-power, directly heated vacuum tube in 1935 for vintage guitar amps and tube radios.
5Y3 was initially intended to be a tube with a metal envelope as per the classification of the North American system of octal tubes without assigning any subscripts –GT, GTA, or G.
Nevertheless, metal variants of 5Y3 never saw the light of the day but were instead launched as 5Y3GT, 5 Y3G, and 5Y3GTA glass tubes. Electrically analogous to the yesteryear type 80 four-pin, the 5Y3 is an octal vacuum tube with an eight-pin base. Type 80 was the go-to standard rectifier used extensively by amp and audio equipment manufacturers until the 5Y3 appeared.
These days, specially designed and created 5Y3s are used as low-output rectifier tubes in low-power vintage tube amps. So, without further ado, let’s take a look at our list of the best 5Y3 rectifier tubes.
Best 5Y3 Rectifier Tubes – 5Y3 Tube Comparison
| Image | Model | Price |
|---|---|---|
| JJ Electronics T-5Y3-S-JJ Amplifier Tube (Top Pick) | Check Price |
 | Sovtek 5Y3GT Vacuum Tube (Close Runner-Up) | Check Price |
 | Groove Tube Gold Series GT-5U4 Rectifier Tube (Direct Replacement for 5Y3) | Check Price |
 | Vintage Emerson 5Y3/GT Rectifier Tube | Check Price |
 | Jammas 1pc Rectifier Shuguang Audio Vacuum Tube | Check Price |
1. JJ Electronics T-5Y3-S-JJ Amplifier Tube (Editor’s Choice)
The T-5Y3-S-JJ amplifier tube by JJ Electronics is a full-wave rectifier tube with a directly heated cathode and an octal base. This JJ Electronics 5Y3 tube has been robustly constructed, featuring a toughened glass covering for ensuring an extended functional life. Compatible for functioning in any 5Y3 position, this JJ T-5Y3-S is found in any standard antique or vintage tube radio.
This 5Y3 amplifier tube works perfectly in any traditional tube-style radio that calls for having a 5Y3GT, 5Y3G, or 5Y3 rectifier tube. Equipped with a spiral filament, this RoHS-compliant 5Y3 tube is a perfect drop-in replacement for any 80 type 4-pin vacuum preamp tube. In addition, audiophiles and guitarists have reported that the JJ T-5Y3 works precisely like any premium NOS 5Y3 in any vintage amp.
For the price, this JJ 5Y3S works as a fantastic recto tube enabling your Fender amp to reproduce the fantastic quality of tone. This 5Y3S can replace the 5Y3GT, 5Y3G, or 5Y3GTA glass tube in your old Gibson, Fender, or Supro bass amp. With the JJ 5Y3S fitted under the hood of your Fender Twin Reverb, you can rest assured that the amp will deliver a soft sound with a sharp attack.
Depending upon the efficiency with which this 5Y3S converts AC to DC, you can expect your amp to give off full, heavy, and dynamic tonality.
Features
- RoHS compliant spiral filament full-wave rectifier tube
- Excellent replacement for any 80 4-pin octal vacuum tube
- Compatible and transposable with 5Y3GT, 5Y3G, 5Y4G, and 5Y3GTA
- Has been tested for shorts, leakage, sonic, microphonic, low noise, amplification, and plate current
2. Sovtek 5Y3GT Vacuum Tube (Close Runner-Up)
The Sovtek 5Y3GT vacuum tube, unlike the JJ T-5Y3S, is an indirectly heated diode meant for rectifying commercial-frequency alternating current. In indirectly heated rectifiers, a heater heats the cathode to attain the optimal temperature for making the tube operational. On the other hand, in a directly heated rectifier, the cathode heats up directly, making the tube operate within 2-3 seconds.
Now both rectifier types have their distinct benefits and drawbacks. However, you’ll need to keep in mind that if you’re using directly heated power valves, you should use a directly heated rectifier and vice-versa. This 5Y3GT rectifier tube from Sovtek has been designed mainly for smaller vintage guitar amps, such as the 1959 5F1 Fender Tweed Champ. The Sovtek 5Y3GT rectifier has a filament voltage rating of 5V, filament current of 2mA ±0.2mA, and 140mA peak output.
This 5Y3GT rectifier is a sturdily built tube perfectly compatible with high-fidelity amp and preamp circuits and heavy-duty pro audio equipment. Music enthusiasts and guitar players heavily rely on the Sovtek 5Y3GT for its overall rich and warm soundstage. The strongly designed plates facilitate optimal heat dissipation, keeping the rectifier safe and effective functioning for long.
Features
- 5Y3GT octal rectifier tube by Sovtek
- Indirectly-heated diode
- Maximum output: 140mA
- Filament voltage: 5V
- Filament current: 2mA
- Ideal for using in older amps
3. Groove Tube Gold Series GT-5U4 Rectifier Tube
You’ll find the Gold Series GT-5U4 Rectifier Tube by Groove Tube in several well-known and celebrated medium-powered bass amps like the Fender Blackface amp. Furthermore, this Gold Series Groove Tube GT-5U4 rectifier serves as the factory preferred rectifier tube for the Triple and Mesa Dual rectifier series having excellent companionability with vintage Bandmasters and Fender Super Reverbs. In addition, this Groove Tube GT-5U4 works as a suitable replacement for 5Y3, 5Y3GT, and 5Y3GTA, helping boost up power and dynamics.
Many guitarists and bassists also fall back on this GT-5U4 for swapping with the stock GZ34 (5AR4) in the Vox Custom AC30C2 30W 2×12 Tube Guitar Combo Amplifier. Replacing the factory set 5AR4 with the Groove Tube’s GT-5U4 goes a long way in promoting heat dissipation, thereby boosting power tubes’ active life. Furthermore, with the Groove Tube installed inside your guitar amp, you can expect the latter to belt out elegant compression typified by smooth highs and warm spongy low-end.
It won’t be an exaggeration to state that this Groove Tube rectifier would define your vintage amp’s tone. The natural internal compression of this GT-5U4 enables your Fender amp to flag, causing the signal to force through the amp.
Features
- Gold Series GT-5U4 rectifier from Groove Tubes
- Drop-in replacement for a 5Y3
- Also replaces 5AR4 in Vox Custom AC30 C2 guitar combo amp
- Generally used in medium powered amps
4. Vintage Emerson 5Y3/GT Rectifier Tube
The Vintage Emerson 5Y3/GT Rectifier Tube performs and works exactly like any NOS (new old stock) black plate 5Y3 rectifier. This 5Y3/GT rectifier works as a guitar amp tube, hi-fi audio tube, microphone, headphone amp tube, triode, diode, and pentode recto tube. In addition, this Vintage Emerson 5Y3/GT goes inside Fender Champ, Fender Princeton, and Fender Tweed Deluxe amps as a full-wave rectifier tube.
These are vintage rectifier tubes that you can set up inside your classic amp and expect a brilliant soundstage, dynamics, and frequency response. To put things in perspective, the soundstage is extensive with depth and sounds sweet overall, characterized by crystal clear midrange.
Features
- Vintage 5Y3/GT rectifier guitar amp from Emerson
- Full-wave rectifier for use in older bass amps
- Replaces 5Z3
- Made in the USA: High-quality performance-driven rectifier tube
5. Jammas 1pc Rectifier Shuguang Audio Vacuum Tube
You’ll find the Jammas Rectifier Shuguang Audio Vacuum Tube inside a wide range of hi-fi guitar amps made during the 60s and 70s. This Shuguang 5Y3/5Y3GT valve is a bonafide, genuine 5Y3 NOS tube based on the original 5Y3 full-wave rectifier developed by RC. The 5Y3 tube helps your amp reproduce muggy vintage sag that eventually creates a velvety feel on the strings.
This Jammas 5Y3GT is a full-wave directly heated rectifier with maximum reservoir capabilities rated at 32 ǔF and minimum resistance of 100 ohms.
Features
- Audio vacuum rectifier tube 5Y3/5Y3GT valve amp for tube amp socket
- Compatible for domestic and commercial applications
- Supports Quick Charge 3.0 (QC3.0)
- It comes with a sub-control switch
5Y3 Vs. GZ34
Speaking, all rectifier tubes function as unidirectional valves which, together with a power transformer, transform AC (alternating current) to DC (direct current). A rectifier is so-called because the valve straightens or corrects the direction in which the electrical current flows. In the world of rectifiers, the 5Y3 and GZ34 (5AR4) sit at the two extremes in the pin-based rectifier spectrum.
Though both 5Y3 and GZ34 are 4-pin rectifier tubes with an oct base, they’re technically very different from each other. While the GZ34 has the maximum current output and the minimum voltage-drop (impedance) amongst all rectifiers, the 5Y3 has the highest impedance rating and minimum current output. The voltage drop contributes towards vintage amps like Fender Princeton and Fender Champ creating signature soundstage.
Voltage drop at maximum signal in the best GZ34 rectifier tubes is much less than 5Y3s as the former tend to be indirectly heated. Rectifiers are classified based on how the cathode gets heated up; directly-heated rectifiers like 5Y3 have a cathode up directly, while an indirectly heated rectifier comes with a heater for heating the cathode. These rectifier tubes come with a separate cathode (B+) for heating the filament, and you should take out a B+ pin before plugging in.
Irrespective of the rectifier type you’re using, always ensure to pull out the B+. Alternatively, you can slot in a flameproof power metal film resistor after hooking up the rectifier tube to achieve more voltage drop for greater sag. When using a flameproof power resistor, you can easily swap out a 5Y3 with a GZ34 and vice versa. Nevertheless, you must pay close attention to the following aspects when switching between these two rectifier types (as they’ve different ratings):-
- Permissible filter capacitance
- DC output current ratings
- Heater current ratings
- Plate resistance rating
When you use both the GZ34 and 5Y3 separately, you’ll be able to make out the distinctions in their performance. It is the distinct internal plate resistance that accounts for the disparity or disparities in their performance. The plate resistance of 5Y3 is about 400ῼ while the corresponding figure for a GZ34 is around 80ῼ (when used as a full-wave rectifier).
No wonder 5Y3s experience a greater voltage drop than GZ34, ultimately resulting in higher total current output for the latter. So it’s better to use a 5Y3 if the AC Mains voltage is high and a GZ34 if the AC Mains voltage is lower.
Can I Substitute a 5U4 for 5Y3?
When planning to swap one rectifier tube with another, the very first thing you should do is compare the pin configuration. If the pin arrangement varies, then you’d be better off steering clear of replacement. Besides checking out the pin pattern, there are a few other factors that you should also consider.
For instance, if you’re thinking of substituting a 5Y3 with 5U4, check out how many milliamperes (mA) current both the rectifiers can supply. Additionally, compare and contrast the voltage drops of both the tubes during rectification. The filament voltage of the tube that you intend to replace should be identical to the replacement or substitute tube.
On the other hand, the filament current must be equivalent to or less than the stock tube. After that, check out the maximum plate voltage of both tubes. Ensure that the max plate voltage is the same as the rectifier that you want to replace.
Finally, you’ll need to evaluate the maximum plate current ratings; max plate current ratings should be at least alike or more than the rectifier replaced.
Conclusion: The Best 5Y3 Rectifier Tube
You can use any rectifier tubes (4 5Y3 and one 5U4) reviewed above in your vintage Fender Champ or Vox Custom AC30 as long as the stock rectifier tube inside it performs optimally. Of course, the brand you finally select could influence the low-level signal processing circuit, but that again would be subjective.
In our opinion, the JJ Electronics T-5Y3-S-JJ is the best 5Y3 rectifier tube available on the market at the moment.