How does one tell if the combo puts out the full rated wattage or if an extension cab is needed? Whats the differences in ohms 4 vs 8, why does it matter, which one is better/more common? is a 1x15 better than a 2x8? I am just lost in a sea of jargon, numbers, and specs at this point. Can someone point me to a resource or explain like I am 5 (which my wife assures me, I act like on a regular basis)?
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If lucky the manual tells you. Combo cabinets with an extension cabinet jack have an 8 ohm internal speaker and usually expect you to add another 8 ohm external speaker. Weirdly, two 8 ohm speakers together are 4 ohms.
4 ohms can pull more power out of an amp than 8 ohms.
Hereâs the Rumble manual. The 8 ohm power number is without any extension. The 4 ohm power number is with an 8 ohm extension.
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They will sound a little different, not better except to your preference. Other factors affect how it sounds also. Itâs possible the 15 goes lower. Itâs possible the 2x8 sounds tighter. Hard to say.
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So for the Rumble 200, you would need to buy TWO additional 200W speakers (because each speaker is 8 ohms) to get the full rated 200W of power?
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Is there a Rumble 200 combo, or do you mean the detached head?
You need two 8-ohm cabinets in total wired in parallel to get 4 ohms. The internal speaker in a combo counts as one cab.
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No. The internal speaker counts as one of the speakers. When you add one external 8 ohm speaker, it will put out 200 Watts.
Each speaker will receive 100 Watts, half the total power output. You need an external speaker capable of 100 Watts.
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BTW, the 2x10 in the 500 still only counts as a single internal 8 ohm speaker for the purposes of this.
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Yep! Basically useful to think of most combos as a head wired to a single cab. Which is literally what they are.
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jesusâŚwtf ; how is someone supposed to know thisâŚ
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They ask, like you did 
If you took electronics training, this is simply series versus parallel wiring. Speaker cabs are wired in parallel to amp heads, generally.
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Nobody does unless they have studied electrical engineering or you find some kind person who takes the time to explain it.
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i mean, as in how is a consumer supposed to know this from the posted specs. its like the reverse of posted food caloriesâŚThis is only 400 caloriesâŚ[but that is per serving and there are 10 servings in 1 thing]. At least with the food you can read the fine print. seems like you need electronics training AND the product manual to undersrand what you are buying.
Does anyone make a combo that puts out the full rated power?
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then thank you kind bassbuzzers
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Smaller combo amps usually put out full power. Like the Rumble 100 and lower.
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Oh they donât, and marketing dudes use this fact to their advantage. Is the Rumble 500 a 500 watt amp? Technically, yes. Does the combo put out 500W of power? Nope, 350. Unless ypu attach an external.
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For reference @Old_WannaBe I have a Rumble 100. I canât turn it up past halfway and use it in the house. So for using at home or small jams its good.
If I were to jump up in size I would go for the Rumble 500 (2 x 10â speakers) For not much more money than the 200 youâve got something that is plenty loud to gig with. Doesnât weigh significantly more and you have the option to add a matching cab to get the full 500w and 4x10 speakers. Loud!
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It turns out it doesnât really matter that much. Thereâs no apples to apples comparison anyway.
The engineering method is the right way to go here. Skip the numbers and add more until itâs enough.
@Barney âs guidelines on which ballpark you are in is close enough for this.
Because of yet more stuff no one could know, 200 Watts is barely noticeably louder than 140 Watts. It better not to think about the idea of wasting leftover Watts. Engineers call leftover Watts âheadroomâ and feel good about them.
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I donât really understand the niche the Rumble 200 is trying to fill. Substantially less capable than the 500, only a little more than the 100. I personally wouldnât consider one.
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Neither do I. It does not make any sense to purchase the Rumble 200.
I think a lot of people are under the misconception that doubling the power doubles the output volume so going to a Rumble 200 from a 100 would give them twice as much output. As has already been mentioned the amp manufacturers really do play on the average consumers lack of understanding.
A Rumble 500 without the external cab is 350 Watts and that is a lot of ear shattering power on itâs own.
Hey @Old_WannaBe what do you plan on using the new amp for?
Also, make sure you are using a good set of ear plugs, although, to be honest, you should already be using them if you are playing, or listening to, anything with the volume cranked up. You donât get a second chance and hearing damage is irreversible and tinnitus is a bitch, as many here can attest to.
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Well, itâs got a different speaker size, which does give it a different sound. That might be important depending on the sound you want.