Dsl 20 what tube for lower gain

Discussion in 'Marshall Amps' started by Javimart1212, Jul 15, 2020.

  1. Javimart1212

    Javimart1212 Member

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    So, I know I might be crazy, but what tube and what location is best to lower some gain on this 20 watt beast? I wish it had some smoother clipping it goes from none to metal in 3 notches..jk
     
  2. pedecamp

    pedecamp Well-Known Member

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    I tried this with a Peavey amp, put a couple 5751 in v1 and v2 and it hardly did a thing, but that doesnt say it wont be different in a Marshall. I suggest getting a few different tubes and try them in V1 and V2 to see what sounds best to you, maybe get one of each to play around with.

    Heres how they compare:
    12AX7 (100%)
    5751 (70%)
    12AT7 (60%)
    12AY7 (45%)
    12AU7 (20%)
     
    Last edited: Jul 16, 2020
  3. Martin Adams

    Martin Adams Member

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    I found changing to lower gain pre amp tubes made little difference in fact it only resulted in about one notch on the gain dial so hardly worth it !
    Try it and see but the change isn’t that drastic
     
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  4. Wojciech

    Wojciech New Member

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    You can try the JJ ECC823, which is half of the ECC83 (12AX7) (the part that feeds the green channel) and half of the ECC82 (drives the red channel). It does a good job in taming the red channel. I've tried it in my DSL 15. It worked for a few months, but then the tube got broken. Not sure if this was a faulty tube, or the fact that ECC823 is not a direct replacement of the ECC83, which could have contributed to the faster wear of the tube.

    I have also tried the 5751 and did not like it at all, as it affected both the green and the red channels.

    Eventually I ended up leaving the ECC83 and modding the amp with the Johny Eggs mod.
     
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  5. pedecamp

    pedecamp Well-Known Member

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    Yeah a JJ ECC823 is a good idea in V1, it will leave the clean channel alone and lower the dirty channel with 12AU7 spec.
     
  6. GIBSON67

    GIBSON67 Well-Known Member

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    Try a ECC823 like suggested above. It worked well when I had a DSL15H I had for a while.
     
  7. Musicmaniac

    Musicmaniac Active Member

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    I use a 5751 in V2 on mine and it works for me.
     
  8. scozz

    scozz Well-Known Member

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    One of the examples above will work, you just need to experiment and find the right tube for the right position.

    I used to always change out one 12AX7 for a lower gain tube in my high gain amps, it does work great once you find the right combination. It lowers the gain to make the high gain channel much more usable imo.

    I’d suggest you buy one of each preamp tube,...12AT7, 5751, 12AY7, and start some tube rollin’!
     
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  9. Antmax

    Antmax Well-Known Member

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    I put a Mullard CV4004 in my V2 for the gain channel. It's almost the same as the regular 12ax7 only quieter so you can turn it up a lot louder. The DSL 20 gets a bit fuller but very loud once it goes higher than 9 o'clock.

    There's a good comparrison chart for 12ax7 type tubes at: https://www.tubesandmore.com/tech-corner/12ax7-comparison-current-made-tubes

    I used a 5751 in my old DSL5c. That worked really well on that amp but sounded a bit restrained and lost a bit of liveliness on my 20hr.
     
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  10. Javimart1212

    Javimart1212 Member

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    I'm probably just gonna buy a cheap attenuator because the tone I find useful, for what we play, is only achievable with low gain and volume at 8 or 9.
     
  11. Antmax

    Antmax Well-Known Member

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    If you fancy some DIY there is a really good thread with ongoing schematics for nice attenuator solutions.

    I'm probably going to buy a Weber Minimass 50W attenuator designed for amps 35w or lower for $160. It's the best affordable one I could find. Has treble compensation, supports 4,8,16 ohm and uses a speaker voice coil motor as a reactive load and also has an unbalanced line out.
     
    Last edited: Jul 16, 2020
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  12. Javimart1212

    Javimart1212 Member

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    I need something a little bigger, I'm fixing to buy an origin 50, just for shits and giggles, in a week; I'm going to need one for sure to tame that baby.

    But for the dsl20 gain topic I'm going go try a 12ay7. I don't think the 5751 will make much difference.
     
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  13. Gene Ballzz

    Gene Ballzz Well-Known Member

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    I have a Weber MiniMass and one of the ones from the thread you linked. The JohnH design from that thread absolutely blows the Weber out of the water! The biggest functional problem with th Weber MiniMass is that it only has two or three "sweet spots" on thew dial that don't mess with tone. Everything in between those "sweet spots" ends up kinda dull, lackluster and wimpy. On the technical side, the Weber is all over the place as far as the impedance the amp sees at different settings. That @JohnH design preserves an important balance between series and parallel impedance, making each setting a "sweet spot" even though there is no dial and they are switched steps od -3.5db each.

    Just Sayin'
    Gene
     
    Last edited: Jul 17, 2020
  14. Javimart1212

    Javimart1212 Member

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    What do you think about the Rivera Rockcrusher? Might buy one of those in a few months.
     
  15. Gene Ballzz

    Gene Ballzz Well-Known Member

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    I think they are well reviewed, but...... It's a lot of $$$! I've never owned one because I'd never pay that much for something that performs such a simple function! If you know how to solder and use a drill, the JohnH unit can be built for less than half the price of a Weber MiniMass! While the designing, development, research and testing gets close to rocket science, building one is not! Even if you need to hire a friend to build it for you, the price would come to about the same as the Weber, +/- $30, depending on material sourcing . And you'll end up with a superior unit!
    Again, Just Sayin'
    Gene
     
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  16. Mitchell Pearrow

    Mitchell Pearrow Well-Known Member VIP Member

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    I don’t have the DSL 20, but I do have the Dsl40c’s, I am at work right now so can’t access the correct locations I installed them in, but I did put a 12AT7 in V2, and a 5751, in either V3 or V4.
    The information is in a thread here but I cannot recall which thread.
    And the difference was less fizz and mud
    Cheers
    Mitch
     
  17. scozz

    scozz Well-Known Member

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    I have a Weber Minimass 50 and I love it and it works great, despite what my good buddy Gene says. These things are subjective and if you read all the reviews on the Minimass you’ll be hard pressed to find a single bad review.

    I’ve owned mine for over a year now and it has made my SC20h come alive, because I’m able to turn the volume up without destroying my hearing! And yes, you are correct, it has some nice features, a 3 position mini toggle switch for treble boost, and it can handle any ohm load, 4, 8, or 16 as you stated.

    Imo for $160 you can’t go wrong,....and you don’t have to build it.

    Bottom line it sounds great, and I’m able to crank my SC20 to get those el34 power tubes really cooking for some delicious power tube distortion.

    I’m an at home player these days, playing in a small room, (14x13). So it’s important to me to be able to take advantage of the tones the SC20 provides when cranked, and enjoy them at reasonable volumes, or low volumes if I prefer.

    Bottom line, it does what it suppose to do,....it does it quite well,.... and it won’t break your bank account.
     
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  18. scozz

    scozz Well-Known Member

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    Double post.
     
  19. Gene Ballzz

    Gene Ballzz Well-Known Member

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    @scozz
    I agree completely with you. My Weber is never going anywhere! The convenience of its easy use for checking out almost any amp for evaluation "on the fly" and as a dummy load on the work bench are absolutely wonderful. I've used mine for several years and have been very pleased. My main point though, is that as good as the Weber works, the @JohnH designed unit is even better, from a tonal and tactile response perspective! Of course, if multiple pedals get involved for "defining" a particular sound or set of sounds, the picture and/or comparison gets a bit more murky. My "core" sound is predicated on guitar plugged straight into the amp and then judiciously and gently adding a few select effects to enhance that "core" sound without compromising it!

    On the other side of this coin, I really enjoy monkeying with stuff, using my hands with shop tools, soldering and fabricating almost as much as I enjoy actually playing music on my guitars! For me, building the JohnH attenuators is more of a fun, enjoyable and satisfying experience, as opposed to being an inconvenience or nuisance! I realize not everyone is so inclined.

    Just My :2c:,
    Gene
     
  20. TXOldRedRocker

    TXOldRedRocker Well-Known Member

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    I love my Weber Mass 100. I'd like to try the JohnH attenuator, but I'm not prepared for that. I've gutted and rebuilt guitars with all new components. I've not built a pedal, or amp, yet. I don't trust myself building an attenuator and hooking it to an expensive amp. I'll get there. But not now. I admire all the guys here that know their electronics inside and out, because I don't.

     
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