Amp or Cab clipping?

Discussion in 'Amps and Cabs [BG]' started by lowdownnotes, Aug 1, 2018.

  1. lowdownnotes


    Feb 24, 2014
    Using an Ampeg PF 500 with Augilar SL 112's Thought it would be a perfect set up at 500 watts getting split at 8 ohms into each cab, which handles 250 watts at 8 ohms. I've experienced farting and clipping at high volumes with my passive 4 string jazz as well as my active 5 string. Pedals haven't helped either. I can get a good tone, but only at medium levels. I've tried putting my volume way up and bringing my gain up to around 8 o'clock. I've also tried with lower volume and higher gain. No difference in clipping/farting at high volumes. What am I missing bass brothers?

    Last edited: Aug 2, 2018
  2. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    You're missing the fact that fartout level is considerably lower than the 250w that makes the speaker blow. If you can get 250w worth of power into that stack without frapping the speakers, you're doing well. The cabs are not made for high power. They're made for medium power.
    HolmeBass likes this.
  3. lowdownnotes


    Feb 24, 2014
    Huh... I was under the impression that these 2 12's would be sufficient for most stage sound situations. So you think the amp is sufficient and a bigger cab configuration will stop the clipping? I was thinking that it might've been the amp.
  4. Kro

    Kro Supporting Member

    May 7, 2003
    New Jersey
    I experienced similar with a 500w amp and two 112s (each rated for 300w). While I do expect that they'd work well for most users at moderate volume levels, the combination proved to be not enough cab for my personal needs. I don't play particularly heavy music styles, just have a few hard hitting drummers, and I like a tone with a solid, but not extreme amount of low-end.

    I think you probably just found where the "not enough" line is for you personally in terms of cabs. Odds are the head being underpowered isn't the issue.
    lowdownnotes likes this.
  5. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    Speaker ratings are electrical, not mechanical. It's not unusual for 250w rated speakers to only handle 100w before they've reached their mechanical limit for clean output.
    lowdownnotes likes this.
  6. lowdownnotes


    Feb 24, 2014
    Makes sense. What did you wind up doing?
  7. Kro

    Kro Supporting Member

    May 7, 2003
    New Jersey
    Drove over into Bucks County PA (from Jersey) to @popgadget 's Scabbey Road studio and tested out a Fearless. Tested an F112 (that's a single 12 + mid) head-to-head against my 112 pair, and to my ear it blew them out of the water. I put in an order for that F112's bigger brother the F115 as soon as I left. The Fearless stuff is pricey, but it still cost less than the combined cost of my 112s.

    Haven't had any such issues since, including outdoors shows.

    I feel like you might be somewhat in the vicinity location-wise. If so, I'd find some time to take the scenic road-trip over and maybe do a head-to-head comparison with your pair as well just to see what you think.
    SactoBass, HolmeBass and lowdownnotes like this.
  8. lowdownnotes


    Feb 24, 2014
    hmm...I was thinking just the opposite....that it was rated for 250 for could go even higher. I was surprised the first time I was clipping. And when I added an envelope filter to it, just went out even faster on me.
  9. Amps clip. Cabs fart. Hairs split.

    The conundrum of it is, that the more speakers you have (in general) the louder you will get, and you may end up turning down the amp and not overworking the speakers. It's a crazy world we live in, right?

    Adding speakers is a much more efficient way to increase loudness than adding watts.
    (Stay within your amp's impedance range of course.)

    Two 50 watt speakers are better than one 100 watt speaker.
    But two 100 watt speakers would be even better.

    Having more headroom is very good.
    Headroom is the amount of capability that you don't use.
    Amp headroom means you don't have to crank it to be loud enough.
    You have a 100 watt amp and the most you are using is 50 watts?
    You have a nice bit of headroom there.

    Speaker headroom means that you can crank the amp and won't have a problem.
    Enough speakers will get you loud enough that you aren't causing the voice coils to bang up against their physical limit of movement.
    If it takes 500 watts of speaker to not bang the coils with a 50 watt amp, then it takes 500 watts of speaker to not bang the coils with a 50 watt amp.

    Do not rely on the rated power of speakers to help you decide what to use. Most manufacturers don't tell you the mechanical limits. They just give you the biggest number they can reasonably use. And not all of them even use reasonable numbers. It's mostly going to be trial and error to find what works for how you play.
    Last edited: Aug 2, 2018
    SactoBass and lowdownnotes like this.
  10. FunkHead

    FunkHead Supporting Member

    Mar 10, 2007
    Yup, gotta determine if it's Clipping or Farting. They are 2 different things.

    I would start by backing way down on the bass knob and boost the mids.

    Your Rig should be able to crush even a loud drummer when EQ'd correctly.
    mbelue and lowdownnotes like this.
  11. lowdownnotes


    Feb 24, 2014
    You're right...I do get better tone with a mid boost. It's clipping, not farting.
  12. Seeing a lot of ''is this 212 going to cut it?'' with a bunch of enthusiastic replies about their ''loud drummer''. Newsflash, every drummer is loud, some are louder. Not seeing the same frequency of broken 12's though. Maybe the message is getting through, I don't think there has been all that much of an improvement in common 12 neo drivers.
  13. This is solid advice.
    SactoBass likes this.
  14. SactoBass

    SactoBass A retired civil engineer who likes all-tube amps!

    Jul 8, 2009
    Lake Havasu City, AZ
    Biiiiiiiig +1. :thumbsup:

    A cab's published rating is the thermal rating, not the mechanical rating. As a general rule of thumb (and I *DO* mean "general"), a cab's mechanical capability is about half of its thermal rating.

    So why don't cab manufacturers publish the mechanical ratings? Because the thermal rating sounds so much more impressive to unsuspecting buyers. And, their sneaky tactics work like a charm!

    As always, there are exceptions. Boutique cabs such as Barefaced, Audiokinesis, Bergantino, and Greenboy cabs are much more capable of handling their published wattage ratings.
  15. Kro

    Kro Supporting Member

    May 7, 2003
    New Jersey
    This is exactly what I was forced to do to compensate as well.

    I got tired of being so constrained eventually. Cutting lows and boosting mids in the name of tone? Awesome.

    Cutting lows and boosting mids just so you don't blow up your cabs? Not so much.
  16. Rumbledore

    Rumbledore Inactive

    Jun 2, 2018
    how fresh are your batteries all around? sometimes an active bass will sound clippy on low batt, maybe some pedals too. messed up leads/cable/cords sounds clippy sometimes, as well as any given in/out jack(s). i hope i could help!
    Kro likes this.
  17. Kro

    Kro Supporting Member

    May 7, 2003
    New Jersey
    The only thing that stopped me from posting similar was this:

    But hey, always good to double check. I've seen countless threads where users were certain that their amp was dying that turned out to be nothing more than a dying battery in an active bass.
  18. lowdownnotes


    Feb 24, 2014
    good point. but bases covered

Share This Page