The Electro-Harmonix 12AX7EH is a preamp tube that provides high gain with ultra low noise. The tube's detailed, musical tone rivals the most desirable NOS types. Unique spiral filament eliminates the filament-to-cathode induced hum common on amps that use AC on the filaments.
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I recently purchased a used SWR bass amp that came with a JJ ECC83 preamp tube in it. The amp was both noisy and the tone was fat and mushy with not much punch and definition. These amps are supposed to be originally equipped with a Groove Tube 12ax7a, so I decided to upgrade the tube. After reading several user reviews, both professional and amateur, I decided to try the EH12ax7. It made a world of difference by greatly reducing the noise, increasing gain, punch and tone definition. Now my SWR SM400s rocks!Electro-Harmonix 12AX7EH Preamp Tube
.I just replaced the stock preamp tube (Sovtek 12ax7wa) with the Electro-Harmonix 12ax7eh tube in my Hartke amplifier and I notice a marked improvement in my rig's sound. This tube makes my amp's distortion sound more thick and creamy, not harsh sounding like the stock tube did. Well worth the time and money swapping the tube as it really made a noticable difference.
Electro-Harmonix 12AX7EH Preamp Tube
.Excellent tubes for alot of applications!
I've been playing around and using Tube Amps for more than 30 years now. I have tried just about every 12AX7 or 12AX7 family of tubes available. These are very good tubes, If used in the right amp. What I have found is every amp, even the same models of the same brands are different in the way they respond to tubes. This means that you have to experiment to find what sounds good to you in your amp. I put one of these in the V1 in my Fender HRD and it was very "glassy" and articulate, however almost brittle sounding. Too much so for me. I then put it in my Kustom 5H Defender I just got too long ago from Custom Guitars Friend and it was fantastic sounding! With that amp it sounds warm, clear and has just the right amount of clarity and growl at the same time. Incidentally I also tried this tube with the Gold pins which costs about $5.00 more. The Gold Pin tube is warmer, which is good for a bright amp, but in a naturally darker sounding amp like my Bassman it sounded Muddy. The original EH 12AX7 here though was great! My advice is to experiment within your budget and keep these tubes in mind as a great starting point!
Very Well made tube!
Very appropiate pricing in today's market! I do wish Custom Guitars Friend would explain their grading system on tubes though, it is very different from other tube supplier's websites. Custom Guitars Friend has very competitive pricing with everyone else, sometimes better, but their grading system is confusing when you are used to terms like "Balanced Triodes", "Matched and balanced" etc. Soft and hard really doesn't tell you much.
Electro-Harmonix 12AX7EH Preamp Tube
.The "before" and "after" sound was amazing. I look forward to many hours of pure tone heaven from now on.
I have a Fender Blues Junior NOS and recently had it modified by BillMAudio, having been on the waiting list for just over a year. I had noticed before modification an occasional volume drop and a jangley noise coming from one of the tubes. On Bill's advice I replaced all of the tubes, which included three Electro-Harmonix 12AX7EH tubes and two JJ Electronics EL34's. Not only did it fix the problems, the hiss and noise dropped out completely. Bill made me aware that it is important to buy matching pairs of the power vacuum tubes, which Custom Guitars Friend supplied. Great products from a great company for a great amplifier.
Seems so far to have added all the warmth and the crunch I need.
Great prices from MF.
Electro-Harmonix 12AX7EH Preamp Tube
.Guess the Grove Tube that came in my new Pro Jr were bad or went bad really fast. As you know a PJ is not known for low hum. But its sits dead quiet at idle now. Need say more? Oh! They were in my mail box in three days. Thanks MF.
Electro-Harmonix 12AX7EH Preamp Tube
.I recently bought a Crate V18-212. It was a great deal, money wise, but needed a makeover. It was time for the Sovtek tubes to go! I used three of these EH 12AX7's to match up to my JJ Tesla EL84's and WOW! We're talking anything from the Beatles, to Hendrix, to some Pink Floyd, even to some Brian Setzer sounds! I'm Totally in love! These pre-amp tubes make the overdrive break up slowly,more creamy than the Tung Sol set I tried, and more harmonic clarity all around.Way to go EH!
Electro-Harmonix 12AX7EH Preamp Tube
.i put 1 of these EH 12ax7 along with a EH el84 in my Blackheart little giant and i gotta say WOW!!! these tubes are the BOMB! my amp sounded good before but the tubes made it way, way better! i have tried several tubes i.e. Groove tubes and others as well and the Electro Harmonix are far superior. great tone, great price, and great craftsmanship. these are the tubes i'll buy from now on!
Electro-Harmonix 12AX7EH Preamp Tube
.I have a Marshall Valvestate and I figured, why not put a new tube in. Not really knowing how much it would affect the tone I gave it a try. It made the hum significantly quieter, and I believe it also made my tone a little crunchier. Im sticking with Electro Harmonix for my tube needs.
Electro-Harmonix 12AX7EH Preamp Tube
.It doesn't matter what type of music you are playing, these pre-amp tubes will clean up your sound and you will be very happy with what you got.
So I installed these in my Bugera 6260 with some JJ6l6 and WOW. I have a great clear heavy sound. I highly recommend these preamps. My highs are more clear and not as ear peircing. My mids are more defined and my lows are not muddy any more. I play Heavy Metal/Thrash Metal and I love my sound now. It is clear and defined but yet sill heavy and punches you in the face.
Have no problems with them.
These wheren't to expensive for the sound I am getting. Would easily pay double and not complain for the sound quality I am getting from these pre-amps.
Electro-Harmonix 12AX7EH Preamp Tube
.My '65 Deluxe Reverb Reissue developed pops and a hissing sound which varied in pitch. Troubleshooting narrowed the problem down to a preamp tube (JJ brand). Both preamp tubes were replaced with made in Russia Electro-Harmonix 12AX7s. The amp has never sounded better. The pops and hiss are gone, Shimmering Highs, Great Bottom End.
Electro-Harmonix 12AX7EH Preamp Tube
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