Attenuating a Marshall with an Effects Pedal

Discussion in 'Marshall Amps' started by John BNY, Dec 19, 2019.

  1. John BNY

    John BNY Well-Known Member Premium Member

    Joined:
    Jul 13, 2013
    Messages:
    1,943
    Likes Received:
    2,860
    Location:
    New York
    I don't attenuate any of my amps, but recently, a friend bought one of my JVMs. But he was having a little difficulty controlling the volume in a small room. We stuck a TS-9 pedal, turned down the gain and volume, and we were able to attenuate the volume.

    So, are there any harmful effects in reducing the loud amp volume with a footswitch? Why do people buy attenuators when you can reduce volume using a footswitch? Thanks for your input.
     
  2. Chris-in-LA

    Chris-in-LA Well-Known Member

    Joined:
    Jul 19, 2018
    Messages:
    755
    Likes Received:
    432
    Location:
    Los Angeles
    Different strokes for different folks. Using a pedal won’t hurt your amp, you can use it on the front end or in the effects loop.
     
  3. wmachine

    wmachine Well-Known Member

    Joined:
    Dec 18, 2015
    Messages:
    235
    Likes Received:
    333
    Location:
    Ohio
    I'm sure more qualified answer will follow, but I think the gist of it is how you reduce the volume. I doubt the pedal reduces it like an attenuator meaning your altering other things (sound-wise) in the process with the pedal.
     
    BanditPanda likes this.
  4. BanditPanda

    BanditPanda Well-Known Member

    Joined:
    Oct 19, 2015
    Messages:
    5,241
    Likes Received:
    5,478
    Location:
    Montreal
    Hi John..if I may answer a question with a question?
    I basically do the same thing i.e. I run my amp at 7 and then bring down the volume by use of the pedals on my board. I don't know if that is " attenuating " as we know it i.e. getting the power tubes to hum while keeping the volume out put bearable.
    By using a pedal are we not just reducing the signal reaching the pre amp and power amp sections and thereby preventing those tubes from getting the juice that makes them hum?
    BP
     
    Jethro Rocker likes this.
  5. El Gringo

    El Gringo Well-Known Member

    Joined:
    Jul 24, 2015
    Messages:
    1,548
    Likes Received:
    1,414
    Location:
    Shakedown Street
    I have to think there is no harm to the amp by the method of using an overdrive like the TS9 versus a load reduction device which will wear the tubes out faster . I think it's safe and a good method to use .
     
  6. wmachine

    wmachine Well-Known Member

    Joined:
    Dec 18, 2015
    Messages:
    235
    Likes Received:
    333
    Location:
    Ohio
    I can tell you this. The point of the attenuator *is* to run the tubes at where the sweet spot is for the tone. Which is pretty much cranked. And cranked wears out tubes faster, yes, but that what you need to get the sound. If you're not going to crank the amp, you don't need a pedal to bring down the volume, just turn down the volume on the amp. A load box does not wear out tubes, a cranked amp does.
     
  7. Nik Henville

    Nik Henville Well-Known Member

    Joined:
    Jul 18, 2018
    Messages:
    1,206
    Likes Received:
    1,955
    Location:
    Eastern Seaboard, the nook-shotten isle of Albion
  8. marshallmellowed

    marshallmellowed Well-Known Member

    Joined:
    Jun 26, 2009
    Messages:
    3,334
    Likes Received:
    3,605
    I'm a bit surprised to hear that someone was having trouble controlling the volume of a JVM. That aside, using a pedal to reduce a guitar level, or line level signal, is completely different than using an attenuator, which dissipates unused energy from a cranked amp.
     
    Last edited: Dec 19, 2019
    MonstersOfTheMidway likes this.
  9. John BNY

    John BNY Well-Known Member Premium Member

    Joined:
    Jul 13, 2013
    Messages:
    1,943
    Likes Received:
    2,860
    Location:
    New York
    I understand the coloring of the tone, so using an OD pedal may not be the best course. But let's say you want to crank the JVM volume to get the tone you want, but want to control the volume. If you were to stick an EQ pedal, and then reduce the volume, you can theoretically take that tone you want while reducing the output volume. Isn't that what an attenuator does?
     
  10. junk notes

    junk notes Active Member

    Joined:
    Dec 10, 2018
    Messages:
    250
    Likes Received:
    234
    Attenuating a Marshall with an Effects Processor:
    four cable method
     
  11. Nik Henville

    Nik Henville Well-Known Member

    Joined:
    Jul 18, 2018
    Messages:
    1,206
    Likes Received:
    1,955
    Location:
    Eastern Seaboard, the nook-shotten isle of Albion
    No. Short answer.
    Slightly longer response...
    An attenuator allows you to drive the tubes (especially the Phase Inverter and output tubes...) into distortion (that's very loud) and then reduce that loudness to levels more suited to small venues, living room or even night-time apartment living... whilst keeping the dirt. It does this by changing some of the loud for heat, so that the signal the speaker gets is reduced. The downside of this is the tonal change brought about by the reduction in loudness as predicted by Fletcher and Munsen. No idea what any of this means???
    Then Google is your friend :cool:
     
    Last edited: Dec 19, 2019
    Mr. Natural and John BNY like this.
  12. pedecamp

    pedecamp Well-Known Member

    Joined:
    Dec 7, 2009
    Messages:
    13,793
    Likes Received:
    10,185
    You can do this but with a pedal think of it like rolling back your guitar volume knob, this is doing the same thing. An attenuator takes your overdriven signal without "rolling it back" and keeps all that overdrive but at a lower volume. Lets use a real life example, I run my SV20H volume dimed and have a pedal in my effects loop to control volume, I get an edge of breakup tone with it set like this, now if I were to turn off the pedal and keep my amp volume dimed like it is my volume would blow the roof off and I'd have tons of gain in my tone.

    Anyway, I've played JVMs many times and have a hard time believing your friend cant get good tone at low volume. He's doing something wrong. :scratch:
     
  13. RLW59

    RLW59 Well-Known Member

    Joined:
    Nov 30, 2017
    Messages:
    605
    Likes Received:
    459
    At least 2 companies sell a simple passive volume box to plug into fx loops. Literally just a pot, a knob, and 2 jacks. If the amp's existing knobs are touchy and abrupt, yes it can help you dial-in the preamp sweet spot.

    But it's just an additional master volume. It's a signal attenuator, not a power attenuator. It lowers the signal that's going into the power tubes -- it doesn't take the power coming out of the power tubes and turn it into heat like a power attenuator does.

    Power tubes distort when they have a big input signal that drives them to try and produce more power than they can. Lowering the input signal to the power tubes reduces the power tube distortion.
    -----------------------
    With earlier designs like Plexis, power tube distortion is a significant part of their iconic tone. If you have one with a loop (modded or reissue), a volume control in the loop reduces the power amp distortion. The only way to get all the amp's distortion is to run it crazy loud, or put an attenuator between the amp and speaker. An attenuator lets you get a distortion component that only happens when the power tubes are trying to put out more than full volume at a reduced volume.

    JVM's and many other modern amps are designed to get all their distortion from the preamp. Most people say they sound worse if you crank them loud enough for the power tubes to distort heavily.

    So since you don't really want power tube distortion with a JVM, few people use attenuators with them. You can get full distortion at lower volume just by turning down the master.

    If you find the controls abrupt or touchy to set, a volume control in the loop is fine. Totally safe. Set the regular knobs then use the loop volume to raise or lower the volume.

    But it reduces how hard the power tubes are working by lowering their input signal. It doesn't let you get power tube distortion like an attenuator.

    It doesn't let you get any tone that's not already available via the amp's existing knobs. It just makes it a little easier to get those tones.
     
  14. John BNY

    John BNY Well-Known Member Premium Member

    Joined:
    Jul 13, 2013
    Messages:
    1,943
    Likes Received:
    2,860
    Location:
    New York
    You definitely can play the JVM at low volume, but he was trying to get to whisper volume. On the clean channel, the MV volume at 1 is decent volume, though it didn't seem like it in my studio. But, if seemed very loud at his house. I tried going on the OD channel, and then reducing the pedal volume to very low, and I was able to get decent tone at a whisper volume. But, I get what you guys are saying -- you are not getting the proper tube tone at a lower volume by going this route.
     
    BanditPanda likes this.
  15. ricksdisconnected

    ricksdisconnected Well-Known Member

    Joined:
    Aug 11, 2019
    Messages:
    1,255
    Likes Received:
    1,862
  16. pedecamp

    pedecamp Well-Known Member

    Joined:
    Dec 7, 2009
    Messages:
    13,793
    Likes Received:
    10,185
    Whisper volume, most people dont know this but tell youre friend those times he needs whisper volume he can plug a guitar and headphones into any OD or distortion pedal and get in some whisper volume guitar play. :yesway:
     
  17. RLW59

    RLW59 Well-Known Member

    Joined:
    Nov 30, 2017
    Messages:
    605
    Likes Received:
    459
    I've never played a JVM so I don't know how touchy the master is.

    But there are amps like the first gen Fender HRD where the master goes from silent to too damn loud between 0~1. Very hard to get "just right" at bedroom volumes.

    A volume in the loop works great for that. Lets you easily fine-tune low volume settings.

    If your buddy is needing to play so quietly that just touching the master makes the volume jump up too high, an extra volume in the loop is fine.
     
    ricksdisconnected and John BNY like this.
  18. Sustainium

    Sustainium Well-Known Member

    Joined:
    Oct 4, 2019
    Messages:
    268
    Likes Received:
    504
    Location:
    Lapeer, Michigan
    Very interesting, I’m definitely one of the “most people”.
     
    marshalltsl and pedecamp like this.
  19. tallcoolone

    tallcoolone Well-Known Member

    Joined:
    Mar 7, 2011
    Messages:
    773
    Likes Received:
    1,225
    “Whisper volume” and 100w tube amps don’t go together. At those levels a Code 25 will sound a lot better than a JVM
     
  20. pedecamp

    pedecamp Well-Known Member

    Joined:
    Dec 7, 2009
    Messages:
    13,793
    Likes Received:
    10,185
    A multi-effects pedal works extremely well and some even have a headphone jack like the Digitech and a drum machine built in. :yesway:
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice