333Xl Infinium tubes question; also related question about Bugera PS1

  1. #1 by Brandon Signorino on 10-11-2018
    Brandon Signorino's Avatar
    Posts: 2

    333Xl Infinium tubes question; also related question about Bugera PS1

    I am brand new to tubes with my 333XL Infinium. How do I know what tubes can be used in it? I have tried to do research but I keep reading conflicting information. The manual says I must use EL34/6550 or 6L6/5881-based tubes. What other tubes are based on these?

    I have heard samples of other amps using a combination of KT88 and 6L6 that sounded cool, but I can't seem to find any information saying whether KT88 would work in this amp. I also heard a sample of an amp using all 6CA7EH tubes that sounded cool, but again, I can't seem to find any information that says whether or not this would work.

    Is there any sort of master list published anywhere that specifies what tubes are compatible with each other (or straight replacements of each other)?

    I am not unhappy at all with the stock tubes in the amp, I just want to know for future reference, as I know I will need to replace them at some point and I wouldn't mind experimenting if I can do it safely.

    On a related note, can the Bugera PS1 attenuator be used with the 333XL Infinium? The information about it says it can only handle up to 100 watts and this amp is 120 watts.

    Thank you!
  2. #2 by Michael Lapke on 10-19-2018
    Michael Lapke's Avatar
    Posts: 1,849
    Hi Brandon,

    Welcome to the forum! Seeing as no one has responded to you yet, thought I'd take a crack at it. The INFINIUM technology in the 333XL allows for auto-biasing of any tube that you place into the amp. It was relayed to me some time ago that "basically if the tube holes line up, it should work" and because of that you are able to get some very interesting sounds out of Bugera Amp products with different valve combinations.

    I'm not a guitar player myself, but a while ago I found this excellent article that goes over different styles of valves, check it out here.

    On a related note, can the Bugera PS1 attenuator be used with the 333XL Infinium? The information about it says it can only handle up to 100 watts and this amp is 120 watts.
    While not ideal, the PS1 can be used with amps higher that 100 watts. The main caveat is that you would need to MAKE SURE and take special care to not crank the SOAK knob all the way up as doing so could potentially damage the PS1. (by effectively feeding too much power) There's no way to effectively calculate what % scale of 1-100 you would be able to max out at with a connected amp of over 100 watts, so there is some risk involved in using the PS1 this way; it's generally not recommended.

    Hope this helps answer your questions.

    Michael Lapke
    Specialist, Community
    MUSIC Tribe
    BEHRINGER
  3. #3 by Brandon Signorino on 10-22-2018
    Brandon Signorino's Avatar
    Posts: 2
    - Michael Lapke wrote View Post
    Hi Brandon,

    Welcome to the forum! Seeing as no one has responded to you yet, thought I'd take a crack at it. The INFINIUM technology in the 333XL allows for auto-biasing of any tube that you place into the amp. It was relayed to me some time ago that "basically if the tube holes line up, it should work" and because of that you are able to get some very interesting sounds out of Bugera Amp products with different valve combinations.

    I'm not a guitar player myself, but a while ago I found this excellent article that goes over different styles of valves, check it out here.
    Thank you for the information! That page on the Seymour Duncan site is helpful.


    - Michael Lapke wrote View Post
    While not ideal, the PS1 can be used with amps higher that 100 watts. The main caveat is that you would need to MAKE SURE and take special care to not crank the SOAK knob all the way up as doing so could potentially damage the PS1. (by effectively feeding too much power) There's no way to effectively calculate what % scale of 1-100 you would be able to max out at with a connected amp of over 100 watts, so there is some risk involved in using the PS1 this way; it's generally not recommended.

    Hope this helps answer your questions.
    This was the response I expected, but I wanted to make sure. I haven't quite run into the need yet... I actually did a recording with the 333XL Infinium at bedroom volume and it sounded awesome. But if I do, this helps with my decision making.

    Thanks again for your help!

    My bands:
    Lavaborne (power/doom metal): https://www.facebook.com/Lavaborne/
    Scorched Earth (groove/death metal): https://www.facebook.com/SCORCHED.EARTH.metal/