Vacuum Tube - 5751, Tube Amp Doctor, Premium Selected

Tube Amp Doctor (TAD)
Vacuum Tube - 5751, Tube Amp Doctor, Premium Selected  image 1
Click to zoom in
Customer Images:
No Images yet! Submit a product image below!

Vacuum Tube - 5751, Tube Amp Doctor, Premium Selected

In Stock

Low-noise Tube for Best Clean Tone!

The TAD Selected 5751 is Tube Amp Doctor's first choice for noticeably improved clarity, smoothness, and a true vintage tone character for most guitar amps! There will still be plenty of gain - so if you own a high-gain preamp that does not have these classic crunch characteristics, the 5751 tube will work wonders. In hi-fi preamps and CD players, the TAD selected 5751 will lower the noise floor and sound smoother and clearer than many 12AX7 tubes.

Especially this low-noise tube is recommended for best clean tone with big bottom, warm midrange and silky top end. Performs great for HiFi too! Replaces any 12AX7A/WA, ECC83, 7025 etc.

Q: When does a preamp tube become a Premium Selected tube?

A: All preamp tubes labeled Premium Selected have passed the following tests:
- Low Noise Test
- Microphonic Test
- Gain Test
- Sonic Tests
- Shock Tests
- Listening Tests
- Balanced Output Test

Item ID:
Tube Amp Doctor Part Number:
Tube Amp Doctor (TAD)
RoHS Compliant
Product Measurements by Type
Body Height49.2 mm
Bulb Temperature180°C
Cathode Current (Ik)5 mA
Cathode to Heater Voltage≤ 90 V
D.C. Grid Voltage, negative-50 V
D.C. Grid Voltage, positive0 V
D.C. Plate Voltage300 V
Grid to Cathode Capacitance (cg/k)1.6 pF
Grid to Heater Capacitance (cg/h)1.3 pF
Grid to Plate Capacitance (ca/g)1.7 pF
Heater Current0.175 / 0.375 A
Heater Voltage6.3 / 12.6 V
Item Diameter22.0 mm
Item Height56.3 mm
Plate Dissipation (Wa)1 W
Plate to Cathode Capacitance0.3 pF
Packaging Information
Packaging Dimensions3.25 in. × 1 in. × 1 in.
Weight (Packaging)0.035 lbs.

My Project Lists

You must be logged in to add items to a project list.

Specifications, Files, and Documents

PDF: Specification Sheet Specification Sheet149.12 KB

Questions and Answers

Click each question to see its answers.
Asked by Anonymous on March 28th, 2018.
Matt H
March 28th, 2018
Preamp tube can not be matched but can be balanced. This is where the two triodes within the tubes are balanced to each other. All TAD preamp tubes come balanced from the factory.
Asked by Anonymous on November 22nd, 2019.
November 25th, 2019
Staff Member
That simply isn't true. 5751 tubes are considered low noise 12AX7s, but all Tube Amp Doctor tubes are run through rigorous testing to ensure top performance. In fact, the 5751 has grown in popularity with guitarists over recent years.

Product Reviews

5.00 out of 5 based on 2 reviews
- September 3rd, 2021
5 out of 5

It's a forward sounding tube in V1 of my Marshall. Solid tonewise. Just not my preference. A bit generic. It's missing pliable mids. Well rounded sounding tube. I prefer a mid flavored tube that brings out my Marshall amp.

Fender guys will love it. Too much. I hate Fender guys.

- May 3rd, 2019
5 out of 5

Replaced the 12AX7s in my VHT Special 6 Ultra with these 5751s. Also replaced the stock 6V6 with a TAD valve. I'm getting nice clean tones, really opened up the differences between pup settings on my Strat, (equipped with with SD STKs). Telecaster, (with Bill Lawrence NF pups), seems to ring a little clearer, but still with plenty of high end edge when played hard. Amp also now sounds better when using an acoustic simulator pedal, (currently a Moore "Acoustikar"). Tele is still a little too bright for this pedal, but Strat and Jazzmaster are much improved.