Studio Vintage: High treble channel hiss?

Discussion in 'Marshall Amps' started by Robus, Jun 5, 2019.

  1. Goldtop11

    Goldtop11 New Member

    Joined:
    Jul 8, 2012
    Messages:
    5
    Likes Received:
    7
    OP, I’m having the exact same issue with mine. I’m used to slight buzz and 60 cycle hum, but my SV20 combo has way more idle noise on the Treble channel than any of my other tube amps. I do constantly have both channels jumped and haven’t un-jumpered it since the first few minutes I tried it, so maybe that’s the issue. I’m glad I’m not the only one though, lol.
     
    Old Punker, Robus and tce63 like this.
  2. Sacalait

    Sacalait Well-Known Member

    Joined:
    Oct 15, 2012
    Messages:
    192
    Likes Received:
    545
    Location:
    South Louisiana
    Yeah, it's definitely an issue. I've recorded with mine though and just pretend I'm doing it old school. Back in the day guitars and amps were noisy as sh*t. I'm pretty sure the only fix is something Marshall can do- if you want it under warranty. Otherwise, put a gate in the FX loop and that solves the problem at idle. Not close to a deal breaker for me man! The tone is to die for!
     
    Old Punker, Sustainium and tce63 like this.
  3. Goldtop11

    Goldtop11 New Member

    Joined:
    Jul 8, 2012
    Messages:
    5
    Likes Received:
    7
    Yeah, I’ll probably go the noise gate route then. I agree with you, as soon as you start playing, the tone is the best I’ve heard. I’m just afraid in between songs when I’m talking to the crowd that the thing is going to be buzzing like no other and driving the sound guy nuts, lol.

    I may contact my dealer and see if Marshall acknowledges that this is an actual problem or if that’s just how plexis are, lol. I have a feeling it’s the latter.
     
  4. trovador

    trovador Well-Known Member

    Joined:
    Dec 10, 2012
    Messages:
    93
    Likes Received:
    270
    Location:
    Boston
    I'm using the Boss NS-2 4 cable method and works like a charm.
     
  5. Robus

    Robus Well-Known Member

    Joined:
    Jan 12, 2013
    Messages:
    268
    Likes Received:
    278
    Location:
    Chicagoland
    Let us know the response. I never found any way to speak a human being at Marshall USA. Is there one?
     
    Old Punker likes this.
  6. Robins64

    Robins64 New Member

    Joined:
    Apr 26, 2020
    Messages:
    2
    Likes Received:
    4
    My sv20 was fine.. now bright channel has a ssh. Sound... seems others having same issue..changed preamp tubes....anyone sort out fix?
     
    Old Punker and tce63 like this.
  7. Robins64

    Robins64 New Member

    Joined:
    Apr 26, 2020
    Messages:
    2
    Likes Received:
    4
    Did you figure out why bright channel making noise? Mines also started .. changed preamp tubes
     
    Old Punker and tce63 like this.
  8. South Park

    South Park Well-Known Member

    Joined:
    Sep 14, 2019
    Messages:
    3,402
    Likes Received:
    2,928
    If you don’t want that hissing noice get off that high gain stuff . When tubes get so much gain they become unstable and pick solar activity .
     
    Old Punker and tce63 like this.
  9. marshallmellowed

    marshallmellowed Well-Known Member

    Joined:
    Jun 26, 2009
    Messages:
    4,258
    Likes Received:
    5,912
    If you run these non master amps with the presence and /or treble controls high, you're going to get hiss. If you don't like it, you can try changing the bright cap, but it's the nature of the beast. Any plexi circuit (1959, 1987x...) will do the same.
     
    Old Punker, trovador and tce63 like this.
  10. Wendigo

    Wendigo Member

    Joined:
    Sep 16, 2011
    Messages:
    70
    Likes Received:
    98
    Location:
    Canada
    Try changing your pick. If that doesn't work, check the tubes. :naughty:
     
  11. wardal

    wardal Member

    Joined:
    Jan 30, 2015
    Messages:
    97
    Likes Received:
    63
    I have the sv 20 combo and there is quite a bit of hiss when turning up the treble chamnel. Very frustrating!
     
    Last edited: Apr 27, 2020
  12. marshallmellowed

    marshallmellowed Well-Known Member

    Joined:
    Jun 26, 2009
    Messages:
    4,258
    Likes Received:
    5,912
    The cure is a noise gate in the loop. I run a simple ISP Decimator in the loop, dead quiet when not playing.
     
    Old Punker and tce63 like this.
  13. Sacalait

    Sacalait Well-Known Member

    Joined:
    Oct 15, 2012
    Messages:
    192
    Likes Received:
    545
    Location:
    South Louisiana
    I'm not noticing it- for some reason. I mostly run the amp on 7 jumping both channels. Yes, there is noise but it's pretty typical for turning an amp way up. But the gate in the fx loop definitely works to eliminate it.
     
    Old Punker and tce63 like this.
  14. ChrisvB

    ChrisvB New Member

    Joined:
    Jun 18, 2020
    Messages:
    5
    Likes Received:
    3
    Hi guys,

    I have the SV20H, running it on a 4x12, and I noticed the same noise in the high treble channel. But its not only whitenoise, its a rustling noise as well, sometimes like leaves in the wind, its not very loud, but loud enough that you notice it.

    Symptoms:

    its only in the high treble channel, and it starts as soon as you turn up the high treble channel up starting from 0. The bass channel has zero noise, very interesting.

    I hear the highbtreble channel noise in 5W mode as well as in the 20W mode. It doesnt matter how much I turn up the high treble volume, that noise stays more or less the same (besides volume at 0 of course).

    It doesnt matter if channels are jumped or if a guitar is plugged in, the noise is always there.

    The noise disappears only in case I install a 4cable method noise gate in the effects loop. Then its gone, so itmust be the preamp right?

    Downside of the noise gate: itsomehow damages the guitar sound on peak signals, it sounds sometimes „damaged“.

    My question to you: do you hear that rustling noise as well? Should I be concerned? Can a failing preamp tube damage my amp?

    Thank you guys!

    Stay well and safe!

    Chris
     
    Old Punker and tce63 like this.
  15. Robus

    Robus Well-Known Member

    Joined:
    Jan 12, 2013
    Messages:
    268
    Likes Received:
    278
    Location:
    Chicagoland
    Design flaw. You described it perfectly. Every unit has it.
     
    ChrisvB and tce63 like this.
  16. High on Tone

    High on Tone New Member

    Joined:
    Dec 25, 2020
    Messages:
    1
    Likes Received:
    1
    It doesn't seem to be as bad when running into my Two Notes Captore instead of the internal speaker. Could it have something to do with the internal speaker, wire, or placement?

    Update: So I tried it with an external speaker cab and it's the same. I tried a couple other SV20Cs at the store... same thing so, I believe Robus might be right... is it a design flaw?

    I will say, however, that when playing the guitar it's not really noticeable and the amp sounds awesome. So, if there is a simple fix It would be great to know.

    And, if there are any SV20H (head only) owners, it would be great to hear if you have the issue.
     
    Last edited: Dec 26, 2020
    Old Punker likes this.
  17. acid

    acid New Member

    Joined:
    Jan 4, 2021
    Messages:
    1
    Likes Received:
    1
    i joined the forum just to add my $0.02

    I picked up a brand new SV20C after reading nothing but stellar reviews. I thought i liked the sound... but daaaamn, i dont know about some of you saying it's not really noticeable. I had my first paid recording sessions in months just this weekend and this amp completely ruined the recording session. The engineer wasn't sure if the SV20C so accurately faithfully recreated the 59 plexi circuity that it comes with all the vintage kinks and idiosyncrasies and what not but he also thought it was so bad, so noisey, so unusable for recording dynamic guitar music that it might as well be malfunctional or defective. He was disapointed with it especially considering its actually made in 2019.

    The i jumper the 2 channels but that treble hiss... once you turn that knob to 2 just to incorporate it into the blend it ruins everything. With my wah and fuzz pedals in the mix it was just death by white noise and hiss and radio signals in a foreign language. Wayyyy less impressive than his $800 made in china vox

    EDIT: i forgot to mention that playing at home with more mellow "jazzier" tones didn't make this noticeable. It's specifically a mix of that high treble channel, high volume, dynamic music, and pedals that made it sound absolutely UNUSABLE
     
    Robus likes this.
  18. TXOldRedRocker

    TXOldRedRocker Senior Discount Member Gold Supporting Member

    Joined:
    May 15, 2020
    Messages:
    619
    Likes Received:
    1,513
    Location:
    Cypress, TX
    Fought the high channel hiss a lot myself. My SV20H is my favorite of my amps. I understand, a certain amount comes with high gain. My SV20H is really quiet, but... I have a new house. I have a voltage regulator plugged into the wall. An isolation transformer is plugged into the voltage regulator. A Furman noise suppressor is plugged into the isolation transformer, and the SV20H is plugged in the Furman.

    Additionally, I specifically chose to replace the tubes with quiet tubes. I used this resource, the link below, bought a few, and rolled some. Only old high gain pedals or unpotted noisy pickups bring the annoying hiss back.

    https://www.tubesandmore.com/tech-corner/12ax7-comparison-current-made-tubes

    I am no EE, and I am likely to be flamed for what I've just typed, but I studied the best I could and came up with this setup.
     
    tce63 and Old Punker like this.
  19. Georgiatec

    Georgiatec Well-Known Member VIP Member

    Joined:
    Apr 23, 2010
    Messages:
    5,577
    Likes Received:
    5,080
    Location:
    Looking for something I don't remember what.
    I have my high treble on 10 and normal on 5-6. My amp is as quiet as an angels fart.

    :shrug:
     
    tce63 and Old Punker like this.
  20. Old Punker

    Old Punker Well-Known Member

    Joined:
    Jun 17, 2020
    Messages:
    521
    Likes Received:
    1,254
    Location:
    Ontario, Canada
    "three nipples and webbed feet" - What, that's not normal?
     
    tce63 likes this.

Share This Page