Announcement

Collapse
No announcement yet.

1967 Super Reverb sounds harsh

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 1967 Super Reverb sounds harsh

    My 1967 Super Reverb sounds harsh. I had a bud do some maintenance on it because it had stopped working. Previously I had gotten used to it over the decades and really liked it. Then it died.

    He went through it and replaced a particular cap he couldn't replace directly because they aren't made anymore. He also replaced the power tubes and maybe a few more. The power tubes are not balanced, I do know that.

    The amp was formerly very bassy. It has the dual-gang master volume that turns down both power tubes that I had installed in the mid-80's. That cost me some highs but I got used to it around the house.

    Now it is brittle-harsh and has lost all of its musicality. It sounds like a really cheap amp. In fact a cheap solid state amp might even sound better than this thing now.

    Do I need to get into the chassis or do I have a bad tube or what?

  • #2
    Are the old tubes still available? Put them back in, and see what happens, but I doubt that is the issue. What about this cap that "isn't made anymore"? All the signal caps are available, and the modern power supply filter caps differ in value by a slight amount that is routinely substituted and makes no difference in performance. 20uF vs. 22uF or 70uF vs. 89uF. A 60's Super Reverb is one of the best sounding amps ever made, if yours sounds harsh, something is certainly amiss. <looking at your bud>.
    It's weird, because it WAS working fine.....

    Comment


    • #3
      It's hosed. I'll trade you for this Roland Cube.

      Just kidding of course. There are A LOT of things that may have made your amp sound darker than it does now, but a capacitor is not likely to be one of them. Most of the parts in that amp aren't made anymore, though every part on that amp has a suitable equivalent part that IS made today. And your dual pot master doesn't turn down the power tubes. It turns down the signal to the power tubes. This is actually an important distinction depending on where this goes for you.

      It could be a bad tube, or tubes. Not likely though. But you mentioned that the tubes "are not balanced" and I'm not sure if you mean the tubes are old and no longer well matched or if you are talking about a "balance" control on the amplifier. At any rate, there are a dozen or more other things I would suspect to make an amp sound "shrill" before tubes.

      Unfortunately I believe that the more you "fix" the amp the more fidelity you'll hear. It is, of course, possible that your friend has something wired wrong or grossly out of adjustment, but I think it's more likely he fixed something that was causing the amp to under perform at some level that you enjoyed. The odds of back breaking the amp through modding are about as good as, well... Go get your Lottery tickets today.

      If you trust your friends abilities as a service tech you should bring this issue up with him. If you don't then you should bring it up with a service you DO trust. I don't know what we, here can do though to be honest. Unless you have some electronic chops and bench gear it will be impossible and even dangerous for you to work on the amp. Even with guidance, because it is severely remote guidance and you may have no skills at this at all. A further complication is that we can only find out if something is wrong. We can't find out what might have been wrong that you liked because your only clue so far is that a new capacitor is in there, somewhere. But that shouldn't cause your problem. In fact your problem is that you no longer have a problem? I think you see the conundrum.

      The next step to REPAIRING or restoring the circuit would be to open it up and take voltage readings from specific locations. This is a high voltage circuit and some familiarity with that is in order before any pawing around. There are a great many safety tutorials on line regarding working on tube amplifier. There are a great many BECAUSE YOU CAN SCREW UP AND DIE if you don't know about and respect this stuff. So...

      Get a decent DMM and read up on the safety issues. If you follow through with this you likely won't be happy with how the amp sounds, but you'll know it's operating correctly.

      Welcome to the forum.
      "Take two placebos, works twice as well." Enzo

      "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

      "If you're not interested in opinions and the experience of others, why even start a thread?
      You can't just expect consent." Helmholtz

      Comment


      • #4
        Thanks for replying everybody.

        My tech friend has a master's in electronics. He replaced some/all tubes with tubes he checked himself. I guess he knows how. Now the amp is just about unplayable without turning down the tone knobs to way low in order to get the shrill out, which robs balls, and I know it's a dirty amp and I've lost the dirt. I mean you can play through it, but it just sucks.

        Plus I wanted it gone through and he said he did. I think it had one leaky busted open filter cap.

        Maybe I need to get a whole new tube set and go from there...

        I just don't feel like spending the dough.

        Without fresh tubes I'd think trying to figure out what it sounds like would be like trying to intonate a guitar with dead strings.

        You could be right, maybe it's time to take it to a regular electronics tech.

        Comment


        • #5
          I suggest you find out exactly what was changed. There's always the possibility that, for example, a cap was accidentally replaced with the wrong value.

          The risk of going to someone else without that knowledge is you add another layer of uncertainly. Your buddy can use this forum too.
          Experience is something you get, just after you really needed it.

          Comment


          • #6
            Agree, go to a real amp tech. Nothing against your engineer friend, he may be an electronic genius. But engineers are usually not technicians. He may know everything there is to know about some capacitor, yet your amp came back unplayable. And further agree, if your buddy is interested in these amps, invite him to come join us.

            I could be way off base here, but when you say it has lost all the dirt - as in a loss of gain perhaps - plus it sounds real tinny, my first thought is you have a break in the signal path and you are listening to the remaining crosstalk.
            Education is what you're left with after you have forgotten what you have learned.

            Comment


            • #7
              Another thing I would suggest is to verify that the speaker section of the combo sounds good on it's own.
              Originally posted by Enzo
              I have a sign in my shop that says, "Never think up reasons not to check something."


              Comment


              • #8
                Originally posted by g1 View Post
                Another thing I would suggest is to verify that the speaker section of the combo sounds good on it's own.
                Indeed! Since the amp was apart (how apart we can't know) is it possible one or more speakers could now be wired in reverse polarity?
                "Take two placebos, works twice as well." Enzo

                "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                "If you're not interested in opinions and the experience of others, why even start a thread?
                You can't just expect consent." Helmholtz

                Comment


                • #9
                  Air_bouquet, what's your location? If you're near one of our competent members perhaps they could help you out.

                  I say this advisedly because we did have a case where the owner of a deflicted amp replied, "Oh I see, you guys just try to sweep business to your members. Wahwahwah, I don't like that!" Whereas all he had to do was drive half an hour across Phoenix and he could have got his amp sorted out by a pro who happens to be an active member here. And another case where a fellow with a '64 Bandmaster peppered us with literally thousands of questions, then sent his amp twice to a self-described amp guru in Texas, was charged over a thousand dollars in fees PLUS shipping, ripped off in other words, and his amp was STILL broken. Then he sent his prize to an honest tech near Sacramento CA who found & fixed the real problem: a ground wire whose solder connection had come loose although it looked good until he tugged on the wire and it popped out. Another couple hun in shipping & shop fees. Now we don't really give a rat's hindquarters where you send your amp for proper servicing, but we do like to see your problems handled honestly and without excess cost. We have a brain trust of excellent techs spread across the USA, Canada, UK plus a couple other countries so why not take advantage if you choose.
                  This isn't the future I signed up for.

                  Comment


                  • #10
                    I'm willing to ask if any wires were re-routed in the course of repair... sometimes, "best engineering practice" doesn't really work in guitar amps... some of the fact that those particular Fender layouts worked as well as they did was dumb luck, and to alter them in the name of "best engineering practice" can also result in "dumb luck."

                    Justin
                    "Wow it's red! That doesn't look like the standard Marshall red. It's more like hooker lipstick/clown nose/poodle pecker red." - Chuck H. -
                    "Of course that means playing **LOUD** , best but useless solution to modern sissy snowflake players." - J.M. Fahey -
                    "All I ever managed to do with that amp was... kill small rodents within a 50 yard radius of my practice building." - Tone Meister -

                    Comment


                    • #11
                      I haven’t played a lot of Blackface Supers. Mainly because I didn’t like them much. I found them excessively bright and not particularly great a getting a warm break up. You really have to crank them and still it’s an open back cab with four 10” speakers. Jazz, country, and clean blues boys tend to use them or people that get their dirt from pedals.... Like Twin Reverbs. It may be working exactly like it should and you liked the way it sounded defective. They tend to be a bit ice picky, especially with some guitars. AND .. an added master volume can really complicate things. It’s rarely done with Supers. If you are playing at a higher volume since the repair to try to get breakup the old speakers may be brittle or damaged as well. If you are in or near a city, try to find a similar one for sale at a store and see if it’s different would be my first suggestion.

                      Comment


                      • #12
                        Chuck brought up some good points. I want to hit a little harder on the idea that maybe your Super didn't sound right and you just got used to that sound.

                        People either love Supers or hate them. The 4x10 make them pretty dog-gone loud for a 40W amp and if you crank that amp to get it into the sweet spot your ears will be bleeding. When you say you lost the dirt, I have to comment that I can't imagine getting any dirt out of mine in the house without the SPL being at the painful level. It's definitely a stage amp and not what I think of as a practice amp for the house. I also don't think of it as a particularly dark sounding amp. when I hear someone talking about a dark sounding Super it makes me scratch my head.

                        The fact that you were using it as a house amp, and say that it was bassy sounding (not at all typical IMO) suggests to me that you had become accustomed to the sound of an amp with worn out tubes. Worn out tubes sound dull and lifeless to me, and they definitely lose their top end. If the amp just up and died on you in a home environment that means that it wasn't being properly maintained. When an amp like that gets serviced the combination of replacing a bad filter cap and worn out tubes is going to make the amp sound VERY different. IMO that amp probably sounded nothing like it should have before it died, and you just got used to the sound of a malfunctioning amp. Now the amp is working as it should and that sounds strange to you.

                        My first move wouldn't be to jump up and hire another tech to look at the amp. I'd ask your pal to make an itemized list of what was fixed/updated/changed and tell us what he did. Unless there's something done that was blatantly wrong, my money is on becoming acclimated to a worn out amp that doesn't work right and thinking that's normal. I like dawg's idea of going out to play another Super for comparison. If it sounds like your fixed Super that'll give you the answer.
                        Last edited by bob p; 01-08-2018, 12:27 PM.
                        "Stand back, I'm holding a calculator." - chinrest

                        "I happen to have an original 1955 Stratocaster! The neck and body have been replaced with top quality Warmoth parts, I upgraded the hardware and put in custom, hand wound pickups. It's fabulous. There's nothing like that vintage tone or owning an original." - Chuck H

                        Comment


                        • #13
                          When it comes to a dark sounding Super, I think this is about as dark sounding as they get if they still sound right:

                          Badfinger. Two Supers. No problem figuring out which amp is giving the great tone, the answer is BOTH!

                          "Stand back, I'm holding a calculator." - chinrest

                          "I happen to have an original 1955 Stratocaster! The neck and body have been replaced with top quality Warmoth parts, I upgraded the hardware and put in custom, hand wound pickups. It's fabulous. There's nothing like that vintage tone or owning an original." - Chuck H

                          Comment


                          • #14
                            I can't see the amps in this video, but the tone is unmistakable.

                            "Stand back, I'm holding a calculator." - chinrest

                            "I happen to have an original 1955 Stratocaster! The neck and body have been replaced with top quality Warmoth parts, I upgraded the hardware and put in custom, hand wound pickups. It's fabulous. There's nothing like that vintage tone or owning an original." - Chuck H

                            Comment


                            • #15
                              As someone who owns a '64 and a '70 Super Reverb- it should NOT be that harsh.
                              Can you possible post some inside the chassis pictures? Anything is possible.
                              Part of the tone stack may have a bad solder joint; possibly incorrect values during replacement.
                              Possible an additional component may have died. All the caps are available.
                              I'm guessing you friend was talking about the dual 25uF caps in the preamp as the one that is "no longer available" - but you can just use 2 individual caps in place of the one dual cap.

                              My '64 is stock and my '70 is modified (Marshall phase inverter values, phase inverter input cap .02 uF and the normal channel tone stack setup with 56K slope, 250pF/.02/.02) and yes they sound very different.

                              As mentioned - check all the speakers. If unsure of the electronics, bring it to a tech - don't risk injury!

                              The tone control should allow a bright sound, but you should be able to roll it off with the treble control.
                              Do all the tone controls work? please check them; start with them all on 1 and the turn each one up individually one at a time and verify.

                              I also agree that you either love or hate a Super Reverb mostly depending on what style of music you play.

                              Comment

                              Working...
                              X