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Electro-Harmonix 12AX7EH Preamp Tube
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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 desirab...Click To Read More About This Product
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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.
Order tubes BEFORE they need to be replaced, and save the gig.
Review Snapshot
by PowerReviewsPros
- Improves sound (23)
- Good quality (21)
- Functional (17)
- Easy to use (15)
Cons
Best Uses
- Concerts (22)
- Practicing (19)
- Back-up (15)
- Reviewer Profile:
- Experienced (22), Professional musician (10)
Most Liked Positive Review
Better than Average 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...Read complete review
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 Musicians 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 Musicians Friend would explain their grading system on tubes though, it is very different from other tube supplier's websites. Musicians 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.
VS
Most Liked Negative Review
can bring new life to amp
Bought this to add to arsenal for tube rolling on Vox Night Train 15 (the first version). Too bright/trebly for V1 spot. Also lowered headroom for cleans compared to some old GE...Read complete review
Bought this to add to arsenal for tube rolling on Vox Night Train 15 (the first version). Too bright/trebly for V1 spot. Also lowered headroom for cleans compared to some old GE long gray plates I bought. Dropped in V2 spot with the old GE in V1 and sounds like a brand new amp. Recorded the tube rolling process and you can really hear the difference. EH way too harsh in V1. If you have Night Train I recommend dumping the Sovteks in pre and power amp sections immediately and get some old Amperex (Holland) EL84s for power section and old long plate (black if you can afford) in V1. Have only tried the EH 12ax7 as far as new manufactured but they really shine in V2.
Reviewed by 59 customers
Displaying reviews 1-20
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Comments about Electro-Harmonix 12AX7EH Preamp Tube:
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!
Comments about 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.
Comments about 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 Musicians 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 Musicians Friend would explain their grading system on tubes though, it is very different from other tube supplier's websites. Musicians 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.
Comments about 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 Musicians 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.
Comments about 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.
Comments about 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!
Comments about 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!
Comments about 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.
Comments about 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.
Comments about 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.
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
I have two Peavey ValveKing heads. One head has Groove Tube Gold Series preamp-amp tubes that i put in new. The other head has these. The head with these sound better and louder then the head with the GrooveTubes. With all the crap rammed down my throat with how good Grooves are suppose to be i just do not agre. I plan on Putting these tubes in the other amp. I also plan on trying Electro Power tubes in one of the amps soon.
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
I replaced my stock 12AX7 tubes from my Fender Hot Rod Deluxe with these things. They sound great. They seem a little darker sounding and have more gain than the stock tubes that came with my amp.
They're worth the price.
Pros
- Improves Sound
Cons
Best Uses
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
I recently re tubed a 1963 Fender "Concert Amp" for a client. I performed a blind test for several guitarists, I rolled 5 different tube brands thru the 1st stage of the pre amp (clean). The consensus was the Sovtec sounded like mush and was horrible in this amp. The Tungsol Reissue sounded nice but was not quite as warm as the EH. Old stock RCA were not quite as warm as the Tungsol. The JJ had a nice bite and edge the other tubes did not have. Everyone agreed, the warm sound of EH was the clear winner. Second place went to the JJ brand. Bottom line, I suggest using different brands of tubes and try "rolling" them thru the 1st stage of your pre amp.
Pros
- Easy To Use
- Functional
- Good Quality
- Improves Sound
Cons
Best Uses
- Backup
- Concerts
- Practicing
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
see my revew for the 6L6-EH tubes, I changed them all at the same time.
Pros
- Easy To Use
- Functional
- Good Quality
- Improves Sound
Cons
- Very Bright Can Be Con
Best Uses
- Backup
- Practicing
- V2 For Vox Night Train
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
Bought this to add to arsenal for tube rolling on Vox Night Train 15 (the first version). Too bright/trebly for V1 spot. Also lowered headroom for cleans compared to some old GE long gray plates I bought. Dropped in V2 spot with the old GE in V1 and sounds like a brand new amp. Recorded the tube rolling process and you can really hear the difference. EH way too harsh in V1. If you have Night Train I recommend dumping the Sovteks in pre and power amp sections immediately and get some old Amperex (Holland) EL84s for power section and old long plate (black if you can afford) in V1. Have only tried the EH 12ax7 as far as new manufactured but they really shine in V2.
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
The tubes arrived on time, unscathed and worked perfectly.
Pros
- Good Quality
- Russian
Cons
Best Uses
- Backup
- Concerts
- Practicing
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
New Sensor Corp. ie Electro Harmonix manufactures ALL tubes that come from Russia. That would include EH, JJ, Genalex, Mullard, Northern Electric....then someone else makes all the Chinese tubes: Shuguang, Ruby...I figure a Russian is a Russian. These work just fine, they are middle of the road on price. I did put Duente Criatura rings on them. I noticed more harmonics on the top end and a small amount of clarity gained on the bottom.
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
I have 3 of these in my USA SVT-CL Ampgeg head. After just a few weeks of moderate playing both preamp tubes became microphonic and the driver tube had a nasty 60hz hum.
Pros
- Easy To Use
- Functional
- Good Quality
- Great harmonics
- Improves Sound
- Warm tone
Cons
- May Get Muddy
- May Sound Muddy
Best Uses
- Backup
- Concerts
- Overdrive Channel
- Overly Bright Amplifier
- Practicing
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
I have a Fender Super Champ XD and Fender Deluxe Vintage Modified. I'm not an electronics expert so I can't tell you why, but !!!! I don't care for these amplifiers with any other preamp tube. This tube really wakes the VM series amps up. The Super Champ XD only uses one 12AX7 and I only replaced the preamp tube closest to the input jack on the Deluxe VM. This was money well spent, these amps now SOUND GREAT !!!
Pros
- Good Quality
- Improves Sound
Cons
Best Uses
- Backup
- Concerts
- Practicing
Comments about Electro-Harmonix 12AX7EH Preamp Tube:
just put a complete set of eh tubes in my peavey classic 30 and it sounds better than it has in a long time. Nice clean tone and nice thick dirty channel and no wierd noises...awesome
Displaying reviews 1-20
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