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  • Help fixing a very vintage Peavey

    Hey there folks,

    I picked up an old 1965-1967 Peavey Musician head and cabinet. I have actually had it for a couple of years now. Here is my story: When I got it the clean channel worked find (and still does), The second channel which has the effects does not send the guitar signal through. I took it apart to see if I could see anything blatent and found a couple of things. I called peavey first, got to talk to one of the old timer techs there. He said since it was so early he would have to try and dig up the original hand drawn schematics. We had a good conversation and I was hopeful, but I never heard back from him and I have tried calling back in a few times with only being able to leave voicemails and no further contact. Anyway I'm hoping someone here can help me. I realize that will be tough without a schematic but here it goes. I have several detail pics I am including. My main issue is there appears to be something that was on the board for the reverb channel but all that is left is ends, the leads are fairly long. I have circled them in one of the pics. I also have a capacitor that came off somehow, I can't remember if I pulled it when first exploring a couple years ago or if it was off when I opened it up. I did remount it this morning but it didn't do anything to help the issue yet. I am assuming the piece that is missing is the culprit. Also when there is input into the reverb channel there is hiss at the speaker and if you alter the high and bass controls you can hear changes in the pictch of the hiss it that matters. So on to the pics

    Overall front left


    Overall front right


    Clean Channel board


    Reverb Channel board Top circle is missing part, bottom circle is where the capacitor was


    Back side of reverb channel board


    Capacitor that was out of place


    Reverb control board

  • #2
    Tech tip #1 - instead of pulling wires off all the pots, just take the knobs and nuts off and let the pots dangle when you flip the board.

    This is not a complex amp really. The copper side of the board is big traces easy to follow. In fact, hold the board over a bright light, can you see the traces from the parts side? Even if not, you can trace out the schematic, and that should shed light on what those parts ought to be.
    Education is what you're left with after you have forgotten what you have learned.

    Comment


    • #3
      Help fixing a very vintage Peavey

      Hey folks,
      I have a Peavey Musician head that dates from around 1965-67. I tried to get a schematic for it, but have been unsuccessful. I talked to one of the long time techs at Peavey and he was supposed to try and find me one, but he said they would have been Hartley's original hand drawn ones. Anyway, he never got back to me and everytime I have tried to call back I get voicemail and no response. So on to the issue. The clean channel is functioning properly, when I plug into the reverb channel no signal gets through. I do here some hiss from the cab and if you turn the treble and bass knobs you can hear a change in pitch in the hiss. Upon opening the unit up, I noticed there appears to be something missing on the 2cd input board. There are 2 leads sticking up which are circled on the pic of that board. The lower circle on that board was a cap that either I removed or had fallen out...I don't recall as I first opened it a couple years ago. Im not versed enough in how these circuits work to know what the missing part is and whether or not its the real issue, but Im hoping someone here might. My guess due to the length of the leads is that it was a disc cap and the cap got pulled off somehow, but that is pure guesswork. So here are some pics of what we have.

      Front left side:


      Front right side:


      Clean input board:


      Reverb input board:


      Backside of Reverb input board:


      More pics to come on the next post.

      Comment


      • #4
        Originally posted by Enzo View Post
        Tech tip #1 - instead of pulling wires off all the pots, just take the knobs and nuts off and let the pots dangle when you flip the board.

        This is not a complex amp really. The copper side of the board is big traces easy to follow. In fact, hold the board over a bright light, can you see the traces from the parts side? Even if not, you can trace out the schematic, and that should shed light on what those parts ought to be.
        Yes...I suppose I could have left them on...I will try that next time for sure. I also suppose I could try and trace out what goes where, but Im not advanced enough to know how the circuit works, Im pretty newb at all this....I have fixed several things by being able to solder and being able to recognize a bad capacitor, etc...but thats about the extent of it for me.

        Comment


        • #5
          This is very close to being Peavey's first commercial product

          I've never seen one online or in person

          From Peavey WEB site:
          1965
          Hartley Peavey Establishes Peavey Electronics Corporation
          Hartley establishes Peavey Electronics Corporation in the loft above Peavey's Melody Music in Meridian, Mississippi. In a time of mass conglomeration, buyouts and price hikes, Hartley establishes a new niche in music and audio equipment, providing "quality gear at a fair price." Production begins on the Peavey Musician™ and Dyna-Bass™ amplifiers, hand-built at a rate of one unit per week.

          Peavey.com: Corporate Profile

          one a week!!!

          Comment


          • #6
            Originally posted by tedmich View Post
            This is very close to being Peavey's first commercial product

            I've never seen one online or in person

            From Peavey WEB site:
            1965
            Hartley Peavey Establishes Peavey Electronics Corporation
            Hartley establishes Peavey Electronics Corporation in the loft above Peavey's Melody Music in Meridian, Mississippi. In a time of mass conglomeration, buyouts and price hikes, Hartley establishes a new niche in music and audio equipment, providing "quality gear at a fair price." Production begins on the Peavey Musician™ and Dyna-Bass™ amplifiers, hand-built at a rate of one unit per week.

            Peavey.com: Corporate Profile

            one a week!!!
            go up 2 more years on that peavey timeline and you will see it in the backround....it also might be the one he is working on the backside of in that pic.

            Comment


            • #7
              Well its no Fender Tweed but quite historic none the less!

              Comment


              • #8
                You may not understand the circuit, but tracing the circuit out gives us a schematic, and we can explain any circuit we have a drawing of.

                Peavey made a bunch of amps with transistor preamps, like the ARtist and Classic. I bet their circuits are real similar to this one.
                Education is what you're left with after you have forgotten what you have learned.

                Comment


                • #9
                  That amp was designed in Hartleys garage way back when and I've worked on a few as well. As Enzo said there is really not much to this amp and in all reality schematic not needed if you have done SS amps in the past. I think Gene sent me the hand drawn ones and I was better off just winging it from knowledge. Change all the e-caps and clean the pots and see what that gets you. Check the power supply secondary unloaded and the check for +/- voltages loaded and make sure the power tranny is ok and check the transistors for shorts and you should be good to go. They have a very unique sound and sound great with vintage pedals like the original tube screamer or BK Butler tube driver.
                  KB

                  Comment


                  • #10
                    You are not showing the power transistors or a full power amp PCB from above.
                    Juan Manuel Fahey

                    Comment


                    • #11
                      Originally posted by J M Fahey View Post
                      You are not showing the power transistors or a full power amp PCB from above.
                      Yes true J M the power-transistors are attached to the bottom of the amp on the transformer side using the old timer mounting screws.
                      KB

                      Comment


                      • #12
                        Yes....sorry I had trouble getting the thread started and neglected to add the next set of pics, here they are

                        Tremolo control board:


                        Power output board?:


                        Power supply board?:

                        Comment


                        • #13
                          Originally posted by Amp Kat View Post
                          That amp was designed in Hartleys garage way back when and I've worked on a few as well. As Enzo said there is really not much to this amp and in all reality schematic not needed if you have done SS amps in the past. I think Gene sent me the hand drawn ones and I was better off just winging it from knowledge. Change all the e-caps and clean the pots and see what that gets you. Check the power supply secondary unloaded and the check for +/- voltages loaded and make sure the power tranny is ok and check the transistors for shorts and you should be good to go. They have a very unique sound and sound great with vintage pedals like the original tube screamer or BK Butler tube driver.
                          I can't say I have much experience other than being able to solder and being able to recognize obvious things like a capacitor that has blown its lid...lol. Before I started changed caps and all that I am trying to pinpoint what the missing part would be that is circled at the top of the reverb channel input board. I assume till that part is replaced I won't know any more.

                          Comment


                          • #14
                            Originally posted by fastmerc View Post
                            I can't say I have much experience other than being able to solder and being able to recognize obvious things like a capacitor that has blown its lid...lol. Before I started changed caps and all that I am trying to pinpoint what the missing part would be that is circled at the top of the reverb channel input board. I assume till that part is replaced I won't know any more.
                            The blue electrolytic cap goes into the center of the board with the positive end connecting to the transistor Collector, so in other words towards the center of the board. At this point unless you can test the old cap, just replace it with a new one.

                            The other missing part at the edge of the board is a cds photocell for the tremolo. It should be sleeved to the small lamp that is to the right of it in the photo. The photocell does not need to be replaced in order for the circuit to pass signal. The tremolo will not work unless it has been replaced, but you can do that at a later time if you want.

                            Comment


                            • #15
                              Originally posted by 52 Bill View Post
                              The blue electrolytic cap goes into the center of the board with the positive end connecting to the transistor Collector, so in other words towards the center of the board. At this point unless you can test the old cap, just replace it with a new one.

                              The other missing part at the edge of the board is a cds photocell for the tremolo. It should be sleeved to the small lamp that is to the right of it in the photo. The photocell does not need to be replaced in order for the circuit to pass signal. The tremolo will not work unless it has been replaced, but you can do that at a later time if you want.
                              Ouch. That's gonna be fun to find.
                              KB

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