1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
     
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

Fender Bassman 100T silent recording help

Discussion in 'Amps and Cabs [BG]' started by mmbass21, Dec 1, 2017.


  1. mmbass21

    mmbass21 Supporting Member

    Dec 10, 2016
    Florida
    Hi everyone, I need some help from other 100T owners. Let me start off by saying that I've been in contact with Fender about my issue and I'm not 100% happy with their answer.

    When I use the head for silent record, I've noticed that the light for silent record comes on as well as the 25w light. I don't have any cabinet connected or speaker cable plugged into the head. Anyone else out there have this head and does the same thing? According to the manual only the silent record light should come on. Now according to Fender, both lights being on isn't necessarily a bad thing that the transformer fail safe will prevent amp failure but the amp showing in 25w will only hurt the life of the tubes.

    I'm not comfortable with those answers at all. This was the second time I used the amp for silent recording and didn't really pay attention to it the first time. This time I noticed that the head was quite hot, actually as hot as if I was running it in 100w mode. I know for a fact that it doesn't get as hot in 25w mode using it conventionally with a cab connected.

    The head is under warranty and I'll exchange it if I have to, however if other owners have the same issue as me then I know it isn't an issue. If any of you only have the silent record light on then I know I need to exchange it.
     
    Last edited: Dec 1, 2017
    Rodrigues likes this.
  2. Rodrigues

    Rodrigues

    May 20, 2016
    Hamburg
    Maybe this helps

     
  3. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    Looking at the schematic, when the switch is in silent record, the speaker output is routed to the dummy load resistors AND the amp is switched into reduced power, 25W. Both the silent record and the 25W LED's should be illuminated. There isn't a way to have the amp in silent record and the power amp turned off. Your amp is working as it is designed to.

    When the amp is in 25W mode, the power tubes are still operating, only at a lower voltage. Since the output is connected to the dummy load instead of a speaker, the audio output is all being dissipated as heat by the resistors. So you have heat generated from both the power tubes and the dummy load. This explains why the amp is running hot.

    When set to post, you are getting a contribution of the power tubes in your XLR output signal.
     
  4. mmbass21

    mmbass21 Supporting Member

    Dec 10, 2016
    Florida
    Thanks beans, I actually saw a demo video on youtube where a guy flipped the switch and I saw both LED's were on so I figured there's no way 2 amps could have the same issue randomly. I couldn't figure out how to delete my original post considering it's from almost 2 months ago. :bassist:
     
    beans-on-toast likes this.
  5. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    For completeness, it still helps others who wonder about this.

    Hope that you are enjoying the amp.
     

Share This Page