1. Win a Broadcaster or one of 3 Teles! The annual Supporting Member Giveaway is on. To enter Click Here. To see all the prizes and full details Click Here. To view the thread about the giveaway Click Here.

Tweaking the Bugera V5 Circuit

Discussion in 'Shock Brother's DIY Amps' started by tele_wah_fuzz, Jan 19, 2014.

  1. dragonfly66

    dragonfly66 Friend of Leo's

    Posts:
    2,159
    Joined:
    Jan 14, 2010
    Location:
    USA
    Decided not to do the bright cap on the volume pot as I really don't want to mess with the circuit, but did decide to try out the Eminence 820H speaker. Hoping for more clarity not necessarily more efficiency, though I'll probably get that too. Currently has JJ EL84 and Tungsol 12AX7.
     
  2. scout2112

    scout2112 Tele-Holic

    Age:
    54
    Posts:
    658
    Joined:
    Nov 6, 2017
    Location:
    Colorado, USA
    I just upgraded my Bugera speaker from a Jensen C8R to a Jupiter 8SC. I highly recommend the Jupiter, as it takes away some of the cardboardy, mid harshness of the Jensen that makes it sound like an 8" speaker. The Jupiter sounds more natural to me. It doesn't sound like a 12" Celestion greenback or anything, but for the money it's a great value as I'd consider the Jupiter to still be in the 'budget' range as far as 8" speakers go. At the time of this writing the Jupiter is $12 more expensive than the Jensen. It's got a bigger, heavier magnet on it than the Jensen, too which is usually a good indication of quality.
     
    Last edited: Jun 28, 2018
  3. walkingspanish

    walkingspanish NEW MEMBER!

    Age:
    43
    Posts:
    1
    Joined:
    Oct 18, 2018
    Location:
    Seattle, WA
    I just wanted to reply to the thread that I appreciate everyone sharing their experiences!

    I was really disappointed with how dark the amp sounded when attenuated. My living conditions require it, and I hate headphones.

    This gave me the courage to mod a V5 Infineon.

    I ran some wire from the gain and volume pots to a DPDT switch, and am currently experimenting with various cap, cap/resistor combinations to see what sound I like best.

    I am incredibly surprised at how much I can sculpt the tone with these mods alone. So cool!
     
  4. gip111

    gip111 TDPRI Member

    Age:
    66
    Posts:
    92
    Joined:
    May 5, 2016
    Location:
    New Jersey USA
    Are these mods also good for the T5 infinium head amp?
     
  5. gip111

    gip111 TDPRI Member

    Age:
    66
    Posts:
    92
    Joined:
    May 5, 2016
    Location:
    New Jersey USA
    So to answer part of my question.. I removed the bottom cover of the T5 (should have taken pics) and looks different than the V5, looks like they have upgraded some electrolitics and tube location is different. I did some tube swapping till I found a combination that made a nice improvement, more clarity and gain. Great sounding amp with bright sounding guitars as Telecasters. If nothing else changes with the sound I'm happy but would still love to get that extra bit of clarity towards the highs. I have it playing through an old fender FM65R using the 12 inch speaker.
     
  6. oscarlat

    oscarlat NEW MEMBER!

    Age:
    28
    Posts:
    1
    Joined:
    Dec 2, 2018
    Location:
    Paris
    I guys, thank you for this very interesting thread, I am very happy I found it!
    I bought a bugera v5 infinium last week, but I found too dark sounding with my ibanez rg2550 with seymour duncan jazz/jb humbuckers. The amp sounded better through the 12" celestion vintage 30 of my mesa-boogie f30, but still was dark with humbuckers and a basswood body. Reading this thread I decided to install the bright caps, instead of returning it to the shop and it changed drastically the eq of the amp, I am so happy of the improvements. With a 220pf on the gain knob and a 270pf on the volume knob, now it has almost too many highs (but still controllable with the tone knob) when I play it through the 12" celestion.
    A little note which could be useful to other noobs like me. The pots of the infinium version are mounted directly on the PCB and have 4 pins. The two central ones are those to be connected by the capacitor to install the bright cap.
    Thank you again!
     
    aquafied likes this.
  7. johnnymg

    johnnymg TDPRI Member

    Posts:
    24
    Joined:
    Apr 8, 2012
    Location:
    Central Cali Coast
    Anyone have info on the V5/T5 hum fix? Found a couple references to this hum and it might be related to the reverb circuit.

    Note: This is not a tube swap issue.
     
  8. BadBen

    BadBen TDPRI Member

    Posts:
    48
    Joined:
    Apr 13, 2013
    Location:
    Gorham, ME
    I just got done spending 2 weeks trying to fix a hum and ended up swapping out a bad cable.

    Dumb cable...
     
  9. eddnix

    eddnix Tele-Meister

    Posts:
    143
    Joined:
    Aug 10, 2019
    Location:
    Leeds, UK
    Apologies for necro-ing this thread but...
    Just want to extend my thanks to the OP. I spent an hour or two today running through the vast majority of the mods and my amp now sounds splendiferous! So good in fact I can now use it with my Les Paul and ES, 'twas far too muddy before. My neighbours will be much happier as the Bugera is the only low level practice amp in the house.
    From me, my neighbours and my pending tinnitus. Many thanks!
     
  10. Flutterecho

    Flutterecho TDPRI Member

    Age:
    48
    Posts:
    4
    Joined:
    Jul 6, 2020
    Location:
    Connecticut
    I added the bright caps on gain and tone. Removed C13 and C22. Added a cap parallel to R24.

    It sounds great but I lost the amp’s reverb. Any ideas?
     
  11. zizyphus

    zizyphus TDPRI Member

    Age:
    33
    Posts:
    6
    Joined:
    Aug 5, 2020
    Location:
    Chicago
    Not sure. Do you have the original v5 or the infinium? I don’t know whether the circuits are the same.

    I have the infinium, and I want to try some of these mods, but I don’t know what applies and what doesn’t. I did remove c22 and got the desired result, but... I’m not sure about the rest
     
  12. Flutterecho

    Flutterecho TDPRI Member

    Age:
    48
    Posts:
    4
    Joined:
    Jul 6, 2020
    Location:
    Connecticut
    So I did the v5 mods on a v5 infinium, and that was my big mistake. I didn’t realize they were different.

    The circuits are not the same, as far as I can determine. The regular v5 schematic is available online, but the v5 infinium schematic is not. I asked on a Bugera Facebook forum if anyone has an infinium schematic, or if they know what the values are for the components I removed, so I could replace them. No one responded. I really wish I never tried the circuit board mods. The bright caps are fine, but even that I feel is unnecessary.




     
  13. zizyphus

    zizyphus TDPRI Member

    Age:
    33
    Posts:
    6
    Joined:
    Aug 5, 2020
    Location:
    Chicago
    Hmmm... I could use a little bit less high end fizziness at the moment. I don't have quite as much treble content as I would like – I'm keeping the tone from 8 to 10 all the time – but the treble that I do have is overly buzzy. Are you having this problem? I may try adding the cap parallel to R24 if that's not something you're experiencing, because presumably that's easy to reverse

    I'm looking for the infinium schematic. I'll post it if I find it...
     
  14. Flutterecho

    Flutterecho TDPRI Member

    Age:
    48
    Posts:
    4
    Joined:
    Jul 6, 2020
    Location:
    Connecticut
    Until we have an infinium schematic to compare against the regular v5, I would caution against any circuit board modifications. I do not see a reason not to experiment with putting bright caps across the gain and tone potentiometers.
     
  15. aquafied

    aquafied NEW MEMBER!

    Age:
    38
    Posts:
    1
    Joined:
    Oct 30, 2020
    Location:
    Manhattan Beach, California
    are these the style of the correct caps to use for the volume and gain?
     

    Attached Files:

    • caps.jpg
      caps.jpg
      File size:
      135.4 KB
      Views:
      46
  16. Kimmo Juutinen

    Kimmo Juutinen TDPRI Member

    Age:
    52
    Posts:
    4
    Joined:
    Apr 5, 2021
    Location:
    Finland
    Hello!
    I have Bugera V5 and was not getting enough highs with guitar humbuckers even when Tone was set to maximum. Made a few studies on tube amplifier circuits. Next post is what I did to my Bugera V5.

    With high voltage equipment always remember safety issues. There may be voltage left in capacitors even when the power cable is disconnected. So be extra carefull.
     
    Last edited: Apr 5, 2021
  17. Kimmo Juutinen

    Kimmo Juutinen TDPRI Member

    Age:
    52
    Posts:
    4
    Joined:
    Apr 5, 2021
    Location:
    Finland
    Inkedv5revcd2_LI.jpg

    Hello!
    I cut the Bugera V5 circuit (red line) and made a jumper (blue line). Sound difference is huge. Lot of highs when needed.

    Afterwards I also changed both cathode resistor bypass capasitors C9 and C13 (2,2 microfarad) into 22 microfarad 50v. Those act as an electron reservoir. You may want to look at to tube amp page:


    https://robrobinette.com/How_Amps_Work.htm#Load_Resistor
     
    Last edited: Apr 5, 2021
  18. Kimmo Juutinen

    Kimmo Juutinen TDPRI Member

    Age:
    52
    Posts:
    4
    Joined:
    Apr 5, 2021
    Location:
    Finland
    o_O By the way Bugera V5 C22 capacitor (47 pikofarad) is meant to be there for cutting off high frequencies which human ear cannot even hear.
     
    Last edited: Apr 5, 2021
  19. Kimmo Juutinen

    Kimmo Juutinen TDPRI Member

    Age:
    52
    Posts:
    4
    Joined:
    Apr 5, 2021
    Location:
    Finland
    Bug3.jpg

    Hi! I changed the Bugera V5 10nF C15 capacitor into 2n2 (2,2nF which is 0,0022 microfarad) to get rid of the lowest muddy frequencies. Enough low frequencies now when playing guitar with Gain knob all the way to maximum setting or with/without boost or overdrive pedals.

    https://robrobinette.com/Voicing_an_Amp.htm
     
    Last edited: Apr 9, 2021
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.