Electro-Harmonix 12AX7 EH Preamp Vacuum Tube
The 12AX7EH provides high gain with ultra low noise and a detailed - musical tone that rivals the most desirable NOS types. Unique spiral filament eliminates that filament-to-cathode induced hum common on AC-powered amps. This tube can be used in phase inverters / preamp sections / driver sections - It really does well in all applications.
Replaced a new Sovtek in V1 in my Boogie DC2 hoping to reduce the noise - it did, but not sure I needed the extra gain, this amp has plenty.
reviewed by: Rich
Use this in the V1 slot in my 1981 JCM 800 2203. Great sounding tube in that position but a little too much gain for my taste in the V2 and PI positions. It's a very quiet tube - no microphonics at all.
reviewed by: Ken B
The EH 12AX7s have consistently low noise for 1st stage preamps, no snap or crackle, just a bit of fizz.
reviewed by: Daniel Griesbach
Love the detail and sensitivity the 12AX7EH offers. Tweaking the pickups' heights really pays off with these tubes.
reviewed by: Bruce
I use these tubes in all my amps - always a predictable sound and excellent quality. Also very durable tubes. Highly recommend!
reviewed by: Mikhail
These replaced the stock tubes in my Primaluna amp.Stock tubes sound nice, but these widened the stereo field quite a bit.
reviewed by: Alex M
Changed out my JJ's with the EH 12AX7's in my Avatar 18 Watt head and what a difference! The amp has always sounded very bright but the EH's brought some much needed low-end to the pre-amp party. The amp still has the Marshall chime it's designed for but now there's some muscle behind it. I'm a fan.
reviewed by: Joe B.
I got one of these EH 12AX7s and put it in the first position in my Marshall 18W clone, replacing a JJ Electronics 12AX7. It made a huge difference. The amp became much more responsive and musical. If one is good, more is better, right? So I replaced all 3 12AX7s with EH 12AX7s, all pentode matched and matched with each other (awesome that Tube Depot provides that service, for a small cost). Also a good result, but the amp seemed to have a much heavier sound, and may have become less touch-sensitive. I will go back to that combination at some point, if I want to go heavy, but for now I am liking the EH 12AX7 in just that first position, mixed with the JJs.
reviewed by: Jon L
I have been using both the 12AT7EH and 12AX7EH tubes and I am extremely happy with the output/control that the Electro Harmonix preamp tubes provide, on both my amps and my client amps. So far, very consistent.
Thumbs up here!
reviewed by: SteveT
great tubes brought a 65 reverb back to life.
reviewed by: wesley
Great tone in my Blackstar series one 50. Smooth, full, sound, had them in my Marshall JCM 900 and they sounded great so I thought I would try them in the Blackstar, I'm glad I did!! They smoothed out some of the harshness the old tubes were giving me, seemed to give the amp a little more kick.
reviewed by: Michael
Very good tone in a Marshall JTM45 clone !
reviewed by: Raymond
Replaced a JJ ECC83S (age unknown) in a Radial Hot British pedal with one of these. The JJ was ok, but I was looking for more filth. Threw in the high gain and low noise options and this thing delivered! I find the distortion dirtier, and the tube is very quiet (quieter than the old one anyway). Very pleased with it.
reviewed by: Joe
Definitely an improvement over the sovtek's i bought last time around in '09. Digging the tone on my Crate Stealth 50w Head. Like a whole new amp! I spent the extra for matched, balanced and high gain. Worth the money!
reviewed by: Jason
I've gone few 12ax7s in the past. I had the EHX on my Swart SST30 years back and I really loved them. Totally hated the JJs, TungSols were clear but a bit bright and has that constant annoying fizz when pushed. Don't get fooled by its price, EHX 12ax7 are great preamp tubes, my new and returned fave! Get them matched, balanced and checked for few extra bucks. Mine came noiseless and perfect. Tube Depot is very dependable and I'll be shopping here again for more. Thanks, folks!
reviewed by: Denny I
Given the low price of these tubes it's easy to overlook them. In my experience they are excellent performers. I've used them in two different audio systems with great results. They're on the warm side. They work very well in a application where the goal is a warm musical tone. I actually preferred them to a couple of NOS 12AX7 tubes. Don't be fooled by the low price. These are excellent tubes. Order the low noise/microphonics for the best result, and get them from Tube Depot.
reviewed by: Gary