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3 answers
Will I have to rebias my Mesa Boogie Dual Rectifier 100watt amp head once I put these in. Also how well do they work in a Mesa Boogie Dual Rectifier 100 watt amp head.
Thank you for your time and effort.
Asked by Anonymous on November 11th, 2016.
Matt H
November 11th, 2016
No, the only time you might need to rebias is when you are replacing power tubes.
Macktires4
November 13th, 2016
Will I have to rebias my EVH 5150 III amp if I put these in
Matt H
November 16th, 2016
No, the only time you might need to rebias is when you are replacing power tubes.
1 answers
I need to retune a Tweed Blues Jr. It currently has JJ pre amp and power amp tubes. I'd like to put the TAD EL-84's in. What preamp tubes would you recommend? (12ax7). I'd like to have a crunch to the tone and natural breakup when on the edge of a clear tone, if that helps. More depth to the tone also, that the JJs seem to currently lack.
Thanks,
Matt
Asked by Anonymous on May 27th, 2016.
JustinG
June 1st, 2016

Staff Member

Top Contributor
I would suggest checking out our tech corner article comparing preamp tubes. Personally I have Tung Sol 12AX7's in mine and I think they are great for the Blues Jr. You also couldn't go wrong with the TAD premium selected 12AX7's.
1 answers
Are these matched or balanced?
Asked by Anonymous on August 24th, 2016.
Hi, we only match power tubes and do not balance preamp tubes.
1 answers
The numbers seem to match up, but will these work in my Orange BT500 Bass Terror Amp?
Asked by Anonymous on May 2nd, 2017.
Yes, according to the Orange website you amp takes two of these tubes.
1 answers
Hi, I haven't been able to find anywhere in the web a straight answer about the actual technical difference between regular and gold versions of these great tubes. I don't mean the difference on how they compare soundwise, but on the technical paper: Is it just the gold coated pins and the rest is the same? are gold pins maybe factory selected under another criterion before gold coating? etc... Thank you very much! Your tube comparison chart is awesome!
Asked by Anonymous on May 16th, 2017.
The pins are gold and this helps to prevent corrosion and buildup on the tubes pins. Other than the pins, they are the same tube as compared to the regular pin version.
1 answers
Will this fit in the space of a Traynor dynabass 400T?
Asked by Anonymous on May 24th, 2017.
When plugged in this tube has the following dimensions: 1.94" (49.2mm) x 0.87" (22mm). You will want to measure your existing tubes to insure a proper fit.
1 answers
Is this the ecc83-s or the ecc83? the image shows its the ecc83-s but the title reads ecc83.
Asked by Anonymous on August 25th, 2017.
The S stand for spiral filament and refers to the internal construction. This will work in any situation where an ECC83/12AX7 is needed.
1 answers
I bought my first tube amp, will these tubes help my vht special 6 sound less boxey/muddy so i can get more tone?
Asked by Anonymous on October 6th, 2017.
Tube characteristics can be different from brand to brand, and because the tone of tubes can be highly subjective, we can not verify if these tubes will get you your desired tone. You can visit the "Tech Corner" of our website for a 12AX7 comparison of current made tubes. This has a wealth of information to help you make a decision.
1 answers
What is the difference between the 12ax7 and the 12ax7-s ?
Asked by Anonymous on February 16th, 2018.
Matt H
February 16th, 2018
The plate design on these is slightly more compact but function just like any other 12AX7.
1 answers
I have Bedrock 600 amp with 415v plate voltage. What power tubes would you recommend?
Asked by Anonymous on June 25th, 2018.
BradWbr
June 26th, 2018

Staff Member
All information we were able to find on a Bedrock 600 stated that it uses EL84 power tubes.
1 answers
I have an older 80's Dean Markley amps signature series 60 that needs new tubes need to go high gain pre amp tubes & loud clean power amp tubes... what you suggest??
Asked by Anonymous on July 20th, 2018.
CurtisG
July 20th, 2018

Staff Member
Please see our 12AX7 comparison chart that has current production 12AX7's listed by gain rating found here https://www.amplifiedparts.com/tech-corner/12ax7-comparison-current-made-tubes
Product Reviews
Purchased to re-tube a block letter 5150. Tubes arrived next day and were extreme well packaged! The amp sounds absolutely incredible!
I put this in my 50 year old Harmony 410A amplifier. This was a drop in replacement for the tube that was originally in the amp. Now my first amplifier from childhood that ended back in my hands after many many years is functioning perfectly.
Really happy with the service from Amplified Parts. This was my first order with them, and I got an order confirmation very quickly, and their site was very good at providing updates. My tubes were shipped the same day I ordered them and they arrived faster than I expected. Thanks!
I was previously running Groove Tube 12AX7's in my amp but see the JJ's highly recommended across various guitar forums I visit. I bought a complete set of 12AX7's and EL84's. I really didn't expect much of a difference, but boy was I surprised. After I plugged these in, my tone was night and day difference over the groove tubes. My amp has never sounded so good, and I didn't want to stop playing. It sounded much more alive, bright, and with a better mid-range punch. These were the gold pin JJ's and I have not compared them to their standard 12AX7's, so I'm not sure how much, if any, a difference the gold pins make. I might try the standard tubes next time just to see if the additional cost is worth it. Bottom line, you won't be disappointed with either JJ tubes or the service from Amplified Parts.
I did not know how many power tube I needed to replace. But since the amplifier is dated 2003, might as well replace all of them. The replacement was successful. Minor adjustment to bias, as advertised. Great tubes, sounds just as good as the OEM tubes.
Very nice, very clean!
Used it to replace the Hughes & Kettner-branded ECC83 on my (low mileage) Attax 100 head (nothing wrong with it, just wanted a fresh one). Sounds a bit clearer and brighter that the H&K. Very happy
Customer service was outstanding. Shipped in a timely manner.
I have a line 6 Bogner amp and this was by far the best improvement to the preamp section. My amp does not sound thin and fizzy anymore. Great job! I paired it with a Mullard reissue to get the best of cleans and distortion. I would buy it again.
Order a pair of ECC83's from JJ's. Great price, quick delivery, excellent customer service.
Installed this 12ax7 in a fender roc pro, I was very impressed with the tone.
I bought a Fender Hot Rod Deluxe used and decided to swap out all the stock tubes for JJs. To my ears the JJs are a bit warmer than the stock Fender tubes which come in the amp. Also, Amplified Parts have the best prices I found online for tubes. Shipping was fast and the tubes arrived securely packaged. Thanks, Amplified Parts!