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Seeburg SHP3 Tone Issues


I noticed in my Seeburg Entertainer  (STD2) that the tone seemed to change randomly and that even with minimal treble there still seemed to be too much high frequencies.  The problem was especially bad on worn records.

What I did:

I decided to take off the pre-amplifier board and inspect the tone switches. Below is what I found.


As you can see the switches were extremely dirty.
I cleaned the switches up with a rubber eraser and some deoxit.  (I forgot to take after photos)

Capacitor Mod:

Also, while I was working on the board I changed out the 2 1.5uF capacitors on the treble switch for .33uF capacitors. All I had in stock was 630volt. They are  over kill for the circuit, but they work.

After the cleaning and modification the amplifier sounds much better and did not have any issues with the tone changing while playing. 


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Comments

  1. Greg GOctober 24, 2018 at 6:58 PM

    Having similar issue with an SHP1 amp. It’s a bit too bright on highest treble setting, but muddy on the MED and MIN settings. The brightness is passable on mint 45s but even slightly worn 45s play with some light distortion. (Especially noticeable on the vocals) Would your fix here work for the SHP1, you think? Thanks in advance - Greg G

    ReplyDelete
    Replies
    1. CodyOctober 25, 2018 at 5:28 AM

      Greg,

      It should work just fine. I will follow up and say that the room your Jukebox is in will also make a difference in tone. My Seeburg Entertainer is in a large garage with concrete floors and hard walls. If your Jukebox is in a room with more objects to absorb the sound the tone will be different.

      One last note just for reference. The larger the capacitor in mfd the more high frequency drops. You may need to experiment and find the correct one for your setup.

      Hope this help.
      Best Regards,
      Cody

      Delete

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