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  • #31
    Re: EL 84s

    I've tried JJ EL84 and TAD EL84 STR in my VHT Super 30, the TAD EL84 sound a lot clearer and bigger bass and stays very tight. The TAD tubes cost a little bit more but I think they are worth it, the JJ's are very good but just not in my VHT.

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    • #32
      Re: EL 84s

      Originally posted by bungalowbill View Post
      OK guys, I'm looking for the fattest and cleanest sounding EL 84s....for a reasonable price. What are your opinions?
      The best EL84 currently produced from my own personal experience is the JJ EL84S. Tone, articulation, construction, reliability and life exceed all the other current production offerings.

      If you are talking NOS though, there are a number of great ones.
      Myles S. Rose
      http://www.guitaramplifierblueprinting.com
      http://la-economy.blogspot.com/
      http://www.facebook.com/mylesr

      Comment


      • #33
        Re: EL 84s

        Originally posted by Myles View Post
        The best EL84 currently produced from my own personal experience is the JJ EL84S. Tone, articulation, construction, reliability and life exceed all the other current production offerings.

        If you are talking NOS though, there are a number of great ones.
        The JJ's worked out great! Very fat and a lot cleaner. I also put one of their ecc83s in V1 and that got rid of a lot of the edgy high end.

        I don't think their pre's would be good in a dark sounding amp, but they work great in a V-32.
        Originally posted by tone4days
        we're not musicians, we're beer salesmen

        Comment


        • #34
          Re: EL 84s

          Originally posted by Fresh_Start View Post
          If you can find them, the Ei version of the EL-84 is warm but still clean sounding. JJs are darker and not as clear to my ear. My Blues Jr. lost some of its chime when I put JJs in. Don't even get me started on the Mesa EL-84s - that's what sent me off experimenting with everything else.

          The Tube Store has the Ei tubes but you may be able to find them for less dough somewhere else.

          Chip

          Chip,

          The Eis were great in a lot of amps tonally. In a Dr. Z Mazerati which has a split bias ... the left two tubes with a seperate bias supply than the right two tubes (not inner and outer as most grid biased amps with four tubes) ... I liked JJs for one pair and Eis for the other pair for some clients.

          But ... the caviat .... the Eis tended to be very unreliable to physical shock such as road travel on tour. If you use these on the road you will need to carry spares as they can fail or become physically microphonic with little or no warning.
          Myles S. Rose
          http://www.guitaramplifierblueprinting.com
          http://la-economy.blogspot.com/
          http://www.facebook.com/mylesr

          Comment


          • #35
            Re: EL 84s

            Originally posted by Yngwiestein View Post
            I've been using Mesa Boogie EL84 tubes in my Budda Superdrive 30 and they are fantastic. Very reasonably priced, $17.99/pair.
            A few things to keep in mind here.

            Mesa used to use the Sovtek EL84 which was the darkest and most constricted sounding EL84 but they were cheap and reliable. If you like the tone of your Mesa with those and have not tried something else you may want to try something else as you may like your amp even more after the change.

            Second ... matching..... Mesa octal tubes (6L6, EL34, 6V6) come with six color codes ..... red, orange, green, gray, blue, white. These codes are on the base of the tube. Red by the way is the coldest tube and white is the hottest within that range. BUT ... you will not see any sort of match or color code on their EL84 tubes. Perhaps their logic is that cathode biased amps are self biasing and they feel the tubes do not need to be matched so these are not matched. If they work and do not make noise individually they pass and are boxed.

            The problem here is that cathode biased amps have a bias network that expects as per design a tube that is close to the design spec of the tube. If a tube is weak it runs cold which sounds grainy and does not allow the amp to produce full power. If the tube is overly strong compared to expected design spec it sounds harsh, runs too hot and has short life.

            The second problem is that when the tubes are more than 20% off on match you will get background hum in the output stage at all levels and loose sustain, articulation and definition as well.

            So ... if you had good luck with the Mesa EL84 offerings it was just that ... luck. It had nothing to do with matching.

            On the other hand, the matching Mesa does on their octal tubes is very good. Due to the fixed bias design of their amps they need to only offer tubes in a narrow range which is a range centered around actual design spec. If you break down the color code and convert it to the GT rating system is looks like this:

            Red = GT 4
            Orange = GT 4

            Green = GT 5
            Gray = GT5

            Blue = GT 6
            White = GT 6

            Mesa grid biased amps are generally overbiased and run cold so I always try to find blues and whites for my Mesa folks that want to use Mesa tubes. If you check the bias on Mesa amps with reds or oranges you may discover that the idle dissapation is as low as 28-30% where 50-60% is expected. Move to a blue or white and you will be closer to where the amp should be running.
            Myles S. Rose
            http://www.guitaramplifierblueprinting.com
            http://la-economy.blogspot.com/
            http://www.facebook.com/mylesr

            Comment


            • #36
              Re: EL 84s

              Originally posted by JumpMarine View Post
              The JJ's are great for sure. TAD's seemed to have a bit higher headroom when I've tried them. The sweetest sounding new production tubes I've tried though were the Ei's. Don't get me started on the GT's, they are the same Russian tubes as the JJ's, but IMHO if you get the JJ's from Eurotubes they do a MUCH better selecting the best tubes from the batch. I've already had the stock GT's fail in my Dr Z and the replacements are starting to get noisey already....popped some JJ's back in and all of my problems went away.
              A few points to try to help here ....

              The JJ is not Russian it is what was Czech, now Slovakia.

              The stock tube in Z EL84 amps were the EL84S (JJ) in a #5-6 rating.

              If you have GT stuff that is going south contact Mike Fineburg at Kaman which took over GT and try to get them replaced under warranty. When I was at GT we would always replace stuff, no questions asked, in any new Z amp.
              Myles S. Rose
              http://www.guitaramplifierblueprinting.com
              http://la-economy.blogspot.com/
              http://www.facebook.com/mylesr

              Comment


              • #37
                Re: EL 84s

                Originally posted by GinoAmes View Post
                Heres my Newbie tube question,(after 23 years of playing I switched to tube,yea!). My amp has Sovtek EL-84s, If I switch to say JJ or Mesa etc. do I have to get rebiased?

                Get rid of the Sovteks .... and new EL84s are plug and play ... no adjustment necessary.

                There are a lot of great vendors but two I use all the time ... and just tell them you want "mid range" design spec tubes are ....

                Supplier of vacuum tubes for guitar, audio, and recording applications. We burn-in, test and match all tubes. Free Shipping on orders $105 and over.

                KCA NOS Tubes. Audio tubes for guitar amplifiers and audiophile equipment. Guitar amplifier parts, guitar amplifier tubes and guitar amp tubes 12ax7, 6v6gt, EL84, EL34, 5751, 12AY7, 6L6GC, 5AR4, GZ34, 5U4GB, Mullard Ecc83, RCA 12AX7, GE 12AY7, RCA 6L6GC, JAN Philips 7581A, RCA 6V6GT Blackplates.


                There are many other great vendors, the two above are just ones that I have years of personal experience with and know how they test things.

                As an example ... from Doug Preston, a matched quad of EL84's is $44. (When I have amps that need a duet I generally buy a quad so I have a backup matched pair). A duet from Doug is $22. Compared to the EL84S from GT the GT cost is $100 for a quad and $50 for a duet so even with a discount the GT version is about twice the price.

                The difference? There is one difference ..... one tube has a GT logo on it and the other has a JJ logo on it.

                From Antique Electric Supply - www.tubesandmore.com a quad is $43 as a side note but if you go there ask for Brandon or Steve or find somebody there that knows me personally and has the documentation I supplied to them so they get you a set of tubes to proper spec.

                All three of the above folks are great but if you want to develop a long term personal relationship with your tube folks and deal with the same person all the time then Doug and KCA are my favorites. Mike at KCA is also one heck of an amp tech as a side note.
                Myles S. Rose
                http://www.guitaramplifierblueprinting.com
                http://la-economy.blogspot.com/
                http://www.facebook.com/mylesr

                Comment


                • #38
                  Re: EL 84s

                  Originally posted by wanmei1 View Post
                  +!
                  The JJ's are not the clearest sounding but they're rich and full with a smooth transition to breakup and a lovely crunch to the distortion.
                  Money spent on NOS preamp tubes is really where it's at.
                  You'll get more of a change in sound from your preamp tubes than you will from the power tubes.

                  Superb point here:

                  You'll get more of a change in sound from your preamp tubes than you will from the power tubes

                  You are right on the money.

                  In many amps the differences in output tubes actually do very little. What you are hearing in many cases is the phase inverter breaking down and that signal being passed to the output tubes. Most 12AX7s these days have plate current as low as 1/2 of expected output and your output section will distort faster in this case or be indistinct of flubby. If you have two tubes that are close to spec, a long plate and short plate you will probably hear a difference as well as the output section is driven harder.

                  In many cases tube makers would rather have you buy a new output set of tubes which are more pricy (and in many cases will require a rebias in grid biased amps) than a plug and play cheaper 12AX7 or other tube in the phase inverter position which has much more effect.

                  Chad Weaver (Brad Paisley) has a selection of phase inverters for Brad's amps that are all documented as to their plate current output, transconductance, plate resistance and actual true gain in circuit (transconductance is a design spec test and not always stated as in an actual amp circuit so both factors are nice to know). Depending on need or venue Chad can change the PI for a given venue or session.

                  But .... the bottom line here is you are right on the money with your statement
                  Myles S. Rose
                  http://www.guitaramplifierblueprinting.com
                  http://la-economy.blogspot.com/
                  http://www.facebook.com/mylesr

                  Comment


                  • #39
                    Re: EL 84s

                    Originally posted by jeremy View Post
                    if myles says jj's then go for jjs/ he is the man when it comes to these things. so much so that groove tubes pays him to be a consultant
                    Actually I was not a consultant for GT I was an employee that did their tube test, development, ran the SAG (special applications group), was their tech support and wrote a number of pieces in The Tube Amp Book so I was there quite a lot and was there from May 2002 until August 15, 2008 when GT was sold to Fender.

                    Part of my deal with them was that I would only work 20 hours a week and would be allowed to be independent so when I felt other folks did something in a better way I could be free to recommend a product that might have come from the competition. This generally worked out fairly well but was the source of many problems now and then An example of one of these was an occasion when I did some testing for Tom McNeil at Ruby Tubes. They had an EL34 that was an exceptional tube. I did a big writeup test report and Tom asked me if he could publish some aspects of the report. Since I put most of my test stuff on my website and feel that anything I put on my website is public domain once it is put on the net I said "sure". The report in it's complete form was put into the front pages of the Ruby Tubes catalogue that was distributed at NAMM that year. Ruby's booth was within sight of GT's booth less than 50 feet away. Many folks showed the catalog to Aspen Pittman I guess. It did not go over well. When people asked me directly if I had something bad to say about the tube I did have one thing to say .... "Ruby has it and GT does not". After that comment got around GT started to buy the EL34BSTR from Ruby and sell it as their EL34C but a bit down the road GT switched to a Shuguang generic EL34 as it was cheaper.

                    So the bottom line reply to what you wrote ... consultant no. Captive employee yes.

                    But today I am a consultant to a number of folks and have no intension of being a captive employee again for anybody.
                    Myles S. Rose
                    http://www.guitaramplifierblueprinting.com
                    http://la-economy.blogspot.com/
                    http://www.facebook.com/mylesr

                    Comment


                    • #40
                      Re: EL 84s

                      Originally posted by Fresh_Start View Post
                      Er, the Blues Jr. runs EL-84s, class AB and fixed bias, and I can tell you that adjusting the bias can help the tone a lot. Of course you have to mod it to be able to adjust the bias first.

                      Many fixed bias EL-84 amps are "less expensive" and manufacturers tend to skip adjustable bias. In addition, a lot of classic EL-84 amps are cathode biased (e.g. Vox) and are therefore self-balancing (no bias adjustment needed).

                      Chip
                      You are on the money here .... the Blues Jr is one of the few grid biased EL84 amps and if you are outside the range they don't work well. The reason Fender went the EL84 route on this amp was price .... a duet of EL84 tubes is less than a duet of 6V6 tubes.
                      Myles S. Rose
                      http://www.guitaramplifierblueprinting.com
                      http://la-economy.blogspot.com/
                      http://www.facebook.com/mylesr

                      Comment


                      • #41
                        Re: EL 84s

                        Originally posted by Fresh_Start View Post
                        IME the manufacturer isn't necessarily going to give you a straight answer either. Do you think a Fender tech at the factory is going to tell you "Yeah, the factory bias for a Blues Jr. is way hot. We really should have put a bias pot in there, but the bean counters wouldn't let us" ?

                        Back to basic rule that if it's fixed bias and there's a bias adjustment, then you ought to check the bias when you replace power tubes. Even if there isn't a bias adjustment, I'd want to check the bias on a new set of power tubes in a fixed-bias amp anyway just to make sure they aren't running really hot (or really cold).

                        Hope this helps,

                        Chip
                        The Blue Jr. works best with the Fender "white" tubes which are GT 4-7 rating. These are mid range tubes (think tubes that are close to design spec of a given tube) and are the proper range. The "blue" tubes (1-3) run cold and the "red" will run too hot. Fender uses all three colors as the way their deal may have worked with GT may have required them to buy some of all the color codes or something like that, I don't know.

                        In any case, if you go to a good tube vendor that tests things properly and ask for a mid range tube or a tube that meets design spec ( RCA / Mullard spec is .... at 250 plate volts, 250 screen volts, -7.3 volt bias the plate current should be 48mA) you will be great.

                        For folks that supply tubes and use a Maxi-Matcher that uses 325 volts and a -12 volt bias just stay in the middle of their silk screened chart on the tester.
                        Last edited by Myles; 11-12-2008, 11:41 AM.
                        Myles S. Rose
                        http://www.guitaramplifierblueprinting.com
                        http://la-economy.blogspot.com/
                        http://www.facebook.com/mylesr

                        Comment


                        • #42
                          Re: EL 84s

                          Originally posted by James Rock View Post
                          More likely they will tell you to stick with the awful (in my eyes) rebranded Sovteks that Fender sells.

                          Fender generally used the GT-EL84R which are indeed the Sovtek. That is the darkest most constipated EL84 around in my personal experience. A great upgrade to these amps is toss those or keep as spares and put in anything else.

                          If the amp has 12AX7R tubes in the front end try replacing those as well with almost anything else. 12AX7EH, 12AX7 Tung Sol reissue, 12AX7C all work great and are not expensive. I like the 12AX7LPS (Sovtek) or the JJ 803S in the phase inverter in these amps but that is my own personal taste for long plates in a PI position in some amps.
                          Myles S. Rose
                          http://www.guitaramplifierblueprinting.com
                          http://la-economy.blogspot.com/
                          http://www.facebook.com/mylesr

                          Comment


                          • #43
                            Re: EL 84s

                            Originally posted by J.LaGrassa View Post
                            I've tried JJ EL84 and TAD EL84 STR in my VHT Super 30, the TAD EL84 sound a lot clearer and bigger bass and stays very tight. The TAD tubes cost a little bit more but I think they are worth it, the JJ's are very good but just not in my VHT.

                            Be sure when you compare two different tubes they both test close to each other. In many cases, most actually ... a person will pick a tube that is at spec over a tube 30-50% below spec which is very very very commmon today.
                            Myles S. Rose
                            http://www.guitaramplifierblueprinting.com
                            http://la-economy.blogspot.com/
                            http://www.facebook.com/mylesr

                            Comment


                            • #44
                              Re: EL 84s

                              Originally posted by Myles View Post
                              Be sure when you compare two different tubes they both test close to each other. In many cases, most actually ... a person will pick a tube that is at spec over a tube 30-50% below spec which is very very very commmon today.
                              cant say for sure how close in spec they were the JJ's were selected from Bob at Eurotubes and the TAD from Dougs tubes, both dealers knew they were for my VHT!

                              My amp sounds very bland with all JJ tubes installed its funny because I always used JJ tubes when I had fender amps and they were great, VHT sounds best with Chinese Pre's (Penta Labs) and TAD Power tubes!

                              Comment


                              • #45
                                Re: EL 84s

                                Originally posted by J.LaGrassa View Post
                                cant say for sure how close in spec they were the JJ's were selected from Bob at Eurotubes and the TAD from Dougs tubes, both dealers knew they were for my VHT!

                                My amp sounds very bland with all JJ tubes installed its funny because I always used JJ tubes when I had fender amps and they were great, VHT sounds best with Chinese Pre's (Penta Labs) and TAD Power tubes!

                                Well .... in the case of preamp tubes there are wide variances that folks call "good tubes". If you are close to SoCal sometime and want me to test and trace some of the stuff you have I would be happy to do so. Actually ... that same deal goes to everybody that might read this. You have to be here in person as I do not ship things back and forth.
                                Myles S. Rose
                                http://www.guitaramplifierblueprinting.com
                                http://la-economy.blogspot.com/
                                http://www.facebook.com/mylesr

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