Ad Widget

Collapse

Announcement

Collapse
No announcement yet.

Reverb input impedance

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

  • Reverb input impedance

    I recently found a 2 spring reverb tank I bought back in the eighty’s,(for a project I never finished) and decided it’s time to add reverb to my old Bogen conversion.
    When I checked the part number I found it has a 150ohm input Z. Most of the schematics I find use an 8ohm Z on the input. Would I need a different transformer than the ones typically used? Or should I change something else? Perhaps I should just spend the dough for another tank?
    Money is always a consideration with kids in college.

  • #2
    need a solid state drive circuit

    Comment


    • #3
      That tank sounds like it might be perfect for Merlin's SRPP driver

      The Valve Wizard
      Building a better world (one tube amp at a time)

      "I have never had to invoke a formula to fight oscillation in a guitar amp."- Enzo

      Comment


      • #4
        Thank you for your response. I was hopping to avoid using any solid state circuits in the signal path of this amp. The SRPP looks like what I need. I'm looking forward to studying the math so I can learn something in the process.

        When I bought the tank I was in college studying op-amps. I was going to build a reverb to use in mixing from my Dokorder 4 track. I didn’t even consider the specks when I bought it. I was in Pembletons bargain basement (I miss that place) getting parts for work when I found a stack of reverb tanks for $5.00 ea. Before I got it to work I found a digital reverb for cheep.

        Comment


        • #5
          Heater voltage

          In order to use the SRPP circuit I have to raise the heater voltage. This amp was made from a Bogen MX30A, the heaters in the preamp tubes are in series using the bias supply for the output tubes. The dc voltages are all negative. I came up with a solution I think will work But before I do anything I wanted to get an opinion to see if there's something I missed. Here Is the original power supply (on top) with the changes I think I need to make (on bottom). I would have the heater for the SRPP in the v5 position. this would raise the voltage 50-60 volts positive to ground.
          Attached Files

          Comment


          • #6
            What would happen if one were to drive said tank from your typical fender tube/transformer drive circuit? It may saturate too early?

            Comment


            • #7
              With the right transformer I think the Fender circuit would work. At the time I didn't know enough about transformers to find the right one. I was looking for any solution. If I were to do it today I would try the Fender tube/transformer drive circuit. The SRPP works pretty good, perhaps not as much drive as I want sometimes, but I love the sound I get from the reverb.

              Comment

              Working...
              X