Genalex - Gold Lion CV4004 / 12AX7 Preamp Vacuum Tube
From our review: "Sonically I find these tubes to have a lot of punch. More gain than a JJ ECC83S and less gain than a Shuguang 12AX7B. Noise is extremely low and microphonics are almost non-existent. I attribute that to the overall build quality. The high end on these tubes may be described as silky. Lots of definition and sparkle without a hint of harshness. The bottom end is not as pronounced as I had expected. Not an issue in a guitar amp and they certainly worked well in my tube pre-amp."
One other note about the construction of these tubes is they have filaments that are almost completely encased in the plate structure. They don't "light up" brightly when working properly.
Other Genalex - Gold Lion tubes 
12AX7 Tube TypesAdditional Information and Downloads
Reviews:
12AX7 Tube Review
Tube Matching Information:
Matched Sections Service
Downloads:
Genalex - Gold Lion CV4004 / 12AX7 Datasheet (PDF)
Download Adobe Acrobat PDF reader
Warranty Information and Return Policy
Warranty Period: 3 monthsAll our tubes are guaranteed for 3 months from the date of purchase. (Any exceptions will be noted on that tube's Warranty tab)
If you receive a tube that does not perform to the manufacturer's specifications, please do the following:
- contact us to get a return authorization
- return it via regular mail within 90 days from when we shipped it, and we will provide an exchange or refund of the full purchase price of the tube.
Returns not related to warranty or defect will be considered at our discretion, and are subject to a 15% restocking fee.
We can not accept returns that don't have an authorization, are past 3 month, or are returned improperly.
These guidelines may be updated without notice.
Ratings & Reviews
5 reviews
Genalex - Gold Lion CV4004 / 12AX7 | Best preamp 12AX7 tube for a vintage Fender Champ Amp
by Gibson Guitar Player
Genalex Gold Lion CV4004 12AX7 Short Plate tube. Dropped this preamp tube into a 1960 Fender Champ amp and the upgrade in tone was fantastic! Creamy smooth highs without even a hint of harshness and no mud whatsoever. Just articulate, nuanced and musical. Sounds great with SD Antiquity humbuckers on a 2020 60s Gibson Les Paul Standard. But Gibson P90s on a ’93 Hamer Special sounded especially good with the amp volume set at halfway where that classic P90 mid-range honk becomes magical through input #1. Later completed the tube upgrades with JJ 5Y3S rectifier and Tung-Sol 6V6GT power tube. All good. Cannot comment on non-Fender amps, but this Genalex Short Plate GL-12AX7-CV4004 is the e-ticket ride for a vintage Fender amp. You will not be disappointed.
Genalex - Gold Lion CV4004 / 12AX7 | Extraordinary Preamp Tube for Classical and Jazz
by David
Replacing stock tubes, I added the GL-12AX7-CV4004 to my McIntosh C70 preamp line stage section along with a Genalex Gold Lion 12AT7 tube. An already excellent preamp was rendered so much better. Smoother and richer sound from my classical, solo string collection. Additionally, the assistance from thetubestore.com couldn't have been more helpful.
Genalex - Gold Lion CV4004 / 12AX7 | Great lower gain preamp tube
by D. Medrano
This 12AX7 tube sounds great in the V1 spot for clean and sparkly tone. I tried it in the phase inverter section and it was a bit too low gain for that purpose. The large plate Gold Lions are better for that position. I now have these GL-12AX7-CV4004 tubes in all my V1 spots on my amps. Recommended!
Genalex - Gold Lion CV4004 / 12AX7 | Smooth singing tone
by Daniel
For reference, I replaced the 3 12AX7 Tungsol's in my Two Rock TS1 with 3 of these GL-12AX7-CV4004, 1 of them matched for the phase inverter. I felt the amp was losing some of it's "character", so I decided to try these Gold Lion tubes out. I chose the cv4004 based on the fact that they described the high end as clear, defined and yet smooth- with a little less bass. By these descriptions it's exactly what I was looking for to complement this amp. Thetubestore was spot on with their description. This amp has a lot of bass eq on tap and I run it pretty low on the dial. These Genalex gold lion tubes even helped create a tighter low end at the same bass eq level I had previously set, very nice.
The highs are clear, defined and very pleasing to the ear. For this amp, it loved the upgrade with these tubes.
The gain doesn't give off any grind or buzz quality, at least in this circuit, just singing gain tone.
Genalex - Gold Lion CV4004 / 12AX7 | Incredible CV4004 tube
by Leroy
This Gold Lion 12AX7 CV4004 gold pins tube replaced my NOS 60’s French Mazda long grey plates in my 1994 Marshall Valvestate.
The tone I got was incredible. It made my amp come alive again .Very fat ,crunchy, creamy & louder compared to the Mazda ECC83. I ordered the Mazda from Belgium years ago. It may have lost some of it’s mojo but still sounds great. It was my favorite tube in my amplifier but I wanted to try this Gold Lion after reading reviews on this GL-12AX7-CV4004. I am very satisfied with this new production tube which found a new home in my Marshall.