Threshold of Farting

Discussion in 'Amps and Cabs [BG]' started by Joe Beets, Apr 3, 2005.

  1. Joe Beets

    Joe Beets Guest

    Nov 21, 2004
    Suppose you have two bass amps. To make it fair, they are both from the same manufacturer. One is an amp head rated at 350 watts driving a 4 ohm speaker cabinet with a 15 inch speaker. The other one is a combo amp also rated at 350 watts and it has the same 4 ohm speaker. Here is a real mind boggler for all of you electrical engineers and bass gear experts. Which rig will experience T.O.F. first, the amp/cabinet rig or the combo amp? I don't know why, but I bet the combo amp will reach the "Threshold of Farting" long before the other rig. There could be a psychological factor involved here too. I know when I stand in front of an amp/cab setup, I feel better and play better. When I stand in front of a combo amp I feel like a weiner and for that reason may be pre-disposed to noticing T.O.F more easily. I'm sure many players on the forum have experienced the nightmare of T.O.F. Were you playing a combo amp at the time?
  2. Fuzzbass

    Fuzzbass P5 with overdrive Supporting Member

    TOF == SBD?

    sorry, I have nothing useful to add.... :D
  3. Sorry, don't know what T.O.F. is but I can say that in your hypothetical scenerio both amps would perform the same. The electronics don't care if the housing is in a cab or on its own. This is all assuming that cab volume is the same and all electronic components are identical.
  4. If all other things are equal like enclosure size and porting, there should be no diference. But to save weight and bulk on a combo, manufacturers will often stick a speaker(s) in a space that's too small and performance suffers as a result. That's one of the reasons I don't care for combos because function too often takes a backseat to form and the result is inferior performance.
  5. T.O.F = Tonally Offensive Farting?
  6. gilbert46


    Sep 21, 2004
    Sacramento, CA
    I got it - Tone Of Fart
  7. :eyebrow:
    T.O.F. is "Threshold of Farting". Look at the thread title!
  8. yea, in this situation, your pumping the same amount of wattage, just that the comob has the same elements but it's packed into one enclosure
  9. Theoretically, there should be no difference. I agree with Mudbass, in that companies sometimes will cut corners on a combo amp, leading to a speaker that may not be able to deliver the tone that the amp is capable of producing. That said, I should mention that of all the combo amps I've ever played, the most powerful of which being a Bloc amp (quite good, I must say; I think it had an 18'' driver), never exhibited the problem you describe. In fact, I would be inclined to think that, if done properly, a combo amp will experience T.O.F. *later* than the head/cab setup, being desinged to operate as one. All technical reason, however, points to there being no difference.

    P.S. I side with you on the "feel better and play better in front of an amp/cab" :p

  10. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    i think really in the hypothetical case presented, TOF isnt the issue. FOLLAW is (fear of looking like a weiner). :D
  11. I caught that right after my last post. I'm Such A LOSER! :bawl:
  12. PunkerTrav


    Jul 18, 2001
    Canada & USA
    You = SAL
  13. Joe Beets

    Joe Beets Guest

    Nov 21, 2004
    "Threshold of Farting" is the technical term for the point at which the sound of your bass goes over the line between a clean or even mildly distorted tone, to a sharp, percussive, broken tone that resembles the sound of a fart.

    When the "Threshold of Farting" is reached it may at first be heard only on the attack of the note but as it becomes more severe it may continue on for the duration of the note.

    T.O.F. may result from numerous causes, beginning with your hand technique. Heavy finger plucking or string thumping will bring the onset of T.O.F. sooner than a light finger or pick action. Other causes are:
    - too much pre-amp gain
    - too much bass or low boost in the EQ section
    - main amp or power amp working too hard (lack of headroom)
    - not enough speaker capability to handle the amp power
    - using a combo amp in a loud rock band

    The easiest way to prevent T.O.F is to get a different gig, like backing up some folk singers. Or you can increase your headroom with a bigger amp and the speakers to handle the increased power. Or add a compressor to your rig. Adding more power is usually easier than refining your hand technique, turning down, or reasoning with a loud guitar player. Once you experience the humiliation of T.O.F you will never want it to happen again. I recommend doing what I did. I got a PLX3002 and several Eden cabinets. No more T.O.F. ;)
  14. TOF isn't applicable to every amp/speaker combination. Some never reach it. My rig with the amp on '10' not only doesn't fart but it sounds awesome (obviously distorted). Unfortunately, it's also loud enough to peel the paint off the walls. ;)

    Speakers will fart when their excursion limits are reached. Some amps will make a similar sound when they reach their output limits, some won't. Depends on their output circuitry and limiting circuitry. As usual with technical stuff, it can't be boiled down to any one particular scenario....:D
  15. Joe Beets

    Joe Beets Guest

    Nov 21, 2004
    T.O.F. can attack a bass player from many directions, that's for sure. When it hits a newbie it can scare the heck out of them. They don't know if they blew something up or what. It's good to learn about the causes and cures before it hits. ;)
  16. My QSC USA900 and 2 Avatar cabs keep me safely out of the FART zone.

    As far as your original post goes I can't see why T.O.F would happen sooner if all components are housed in the same enclosure. I guess neither one of us need to worry about that! :bassist:
  17. Folmeister

    Folmeister Knowledge is Good - Emile Faber Supporting Member

    May 7, 2003
    Tomball, Texas

    1. Good band name

    2. Sounds Tantric

    3. Tim Curry said it best. "Antici. . . . . . . . . . . . . . . . . . . pation!

    4. Did L. Ron Hubbard write a book about that?

    5. Someone consult NASA
  18. It's obvious to me now that you have never stood in front of the jaw-dropping tubey goodness combo known as the Eden Metro
  19. Nick man

    Nick man

    Apr 7, 2002
    Tampa Bay
    2.73 beans burritos
  20. Every Metro I've ever tried had the fartage at what I would consider very low volume unless there was an extension speaker connected. Like not even at coffee shop volume. I have a feeling that the cab portion of that particular amp isn't optimally designed because the regular Eden 210 cabs sound good and can handle a fair chunk of power.... Now that was a few years ago so they may have corrected it but I remember being very disappointed in it compared to the other Eden gear I tried...