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2 questions

Discussion in 'Amps and Cabs [BG]' started by TooL_051685, Jan 3, 2006.

  1. TooL_051685


    Jan 19, 2005
    before I begin , i did do searches and found some useful info, but didn't find direct answers to either of my questions, so please don't yell at me

    Well I've decided its time to upgrade to a better rig. I've pretty much narrowed the head down and decided on the nemesis 650

    Question 1 : Now I'm trying to decide on a cabinet
    i've been looking at avatar's b410 neo and b410 kappa Pro
    Just wondering if anyone had heard both cabinets and could tell me the main difference is, other than power handling and weight?

    Question 2 : I know it is not a good idea to under power a cabinet because people tend to run the amp into clipping to compensate for the low power output. My question is how loud would I be able to turn this head up (for example 1/2 way, 2/3 way, etc...) before it starts clipping? would i just be better off buying a cab w/less power handling? Thinking about these power issues is making me reconsider my head and now im thinking about the kustom groovebass, but I really like the features of the nemesis.

    sorry I know question 2 was really like 3 questions instead of 1

    thanks guys
  2. It really doesn't matter about the cab having a larger power rating than the head. Just be careful about how high you turn up your amp - and back off the low end a bit when you crank it.

    When it comes to the cab - go for a 8ohm model - then you can re-wire it to 2 ohms to get the most out of the head.
  3. fatsobasso


    Dec 24, 2005
    Ormond florida
    I thought you cannot rewire a cab for ohms,speakers have set ohms,2 16ohm speakers in parallel=8 ohms in the cab,how do you change that?
  4. AxtoOx


    Nov 12, 2005
    Duncan, Okla.
    My Nemesis NC210 has a 250 watt amp, It clips at 1/3 gain w/ an active F Bass BN5 on my B string,but I have no issue w/ the volume it puts out, for a little 250 it cranks.
    My Eden WT1205,they changed the gain on and I have to turn up the gain all the way and slap to get it to clip. That thing is REALLY loud.
    I would think yours would be like my Nemesis.
  5. Okay - if you have for example - a 4x10 cab at 8ohms;
    These are usually wired in "series-parallel". Thats four 8ohm speakers, with a pair of each wired in series (2 x 16ohms), and then both in parallel = 8ohms.
    Your average 4 ohm cab will tend to have four 4ohm speakers in this same config.
    So - assuming you have four 8 ohm speakers, wiring all 4 in parallel will give you a total load of 2 ohms. I'd be careful about this kind of wiring tho - many amps will drop their guts running this kind of load. :eek:
    Wiring in series = double
    Wiring in parallel = half - as a rough estimate only of course.
    Hope it helps.
  6. theshadow2001


    Jun 17, 2004
    I think that you have the wrong approach to the wattage rating of your speakers. The time when your going to do damage is when the amp is clipping. This is when you try to get more out of the amp than its capable of outputing.

    Changing the speakers for a lower rated wattage isn't going to make your amp magically stop clipping if your running it too hot.

    I think that the idea of underpowering arises from people who have a speaker cabinet that can take more power than the amp can output. So they think that its ok to drive the amp as hard as they like without damaging the speakers. This isnt true. If your amp is clipping it can still damage speakers that have a higher wattage rating than your amp.

    If I did have an amp clipping though I'd rather a highly rated cab take the signal than a low rated one.Either way the amp will damage the cab. But I would imagine the higher rated cab would handle it a little better.
    All that being said the bottom line is: Don't clip your amp!

    People have amps rated 1.5 to 2 times the wattage of their speaker cabinets to provide head room. That is they don't use the full power of their amp. This will almost guarentee that a clean signal is constantly given to the speaker cabinet(s)

    As for how much you can turn up depends on what way you have your eq set up and what type of bass your using how hot it's output is etc. If theres no clip LED on the output stage of the amp try bring the volume up to what you need. If the speaker starts to sound like its farting bring the output back until it stops farting.

    I think that one way of looking at buying a new rig in terms of wattage would be to ask how much wattage your going to need. Then get speaker cabinets that can handle the wattage (RMS). Then buy an amp that can output 1.5 to 2 times the rated wattage of the cabinets. This means you'll be getting the wattage you need without clipping and you'll be getting the most out of your speakers
  7. TooL_051685


    Jan 19, 2005
    thanks. that makes sense, but i remember hearing that your amp can start clipping far before it makes audible "farting" or unwanted sounds. Is it just not clipping enough to damage it until it gets to point of farting? Is there another way to tell if its clipping?
  8. Clipping doesn't *automatically* equate to damage. Speakers get damaged when one or more components are (1) given more power than they can handle or (2) asked to move more than they're readily capable of (overexcursion). The thing to watch for in clipping is that it means you can be putting out *more* than the rated output, so sometimes when you think you're within a speaker's capacity, you're actually giving it too much power. This can be a particular problem if you're giving a tweeter too much juice.

    I would say the sensible approach is to (1) get a bigger amp than you need and then (2) buy a cab that can handle at least the amount of power that you're likely to be using. Anywhere from 50% of the amp's rated power on up to 100% or 150% or more is a reasonable rule of thumb, if you're not driving the amp too hard.
  9. Whether you "tend to run the amp into clipping" has absolutely nothing to do with the ratio of the amp's power to the cab's power handling. It has to do with the ratio of the power the amp can put out to the power you actually need to do your job.

    If you even think you might be running your amp into clipping, getting a lower-rated cab would probably be exactly the wrong thing to do, because it would get you in trouble *sooner*. (The exception might be if the lower-rated cab was much more efficient, so that you could run your amp lower and still get as much volume or more. But this is by no means guaranteed.)