Curious how the watts are split. Lets say I have an 800 watt head going into a cab that can handle 1000 watts, if I connect the head to a second cab, does the second cab also need to be able to handle at least 800 watts? Do both cabs get 400 watts? Ohms shouldn't be an issue. Thanks
Enjoy the benefits of a premium membership!
Upgrade Account
-
TalkBass has been independent since 1998. Add your voice.
Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
Join free Log in
Want zero display ads or expanded classifieds tools? Compare plans.
Pairing two cabs together
- Thread starter epic!
- Start date
Depends on the impedance of each cab. For example, if both cabs are 8 ohm cabs, the power will be split evenly. So basically, the cabs will split the power outputed. If one cab has a different ohm rating, the cabs will not split evenly. If the impedence ends up too low (the overall impedences will be lower than either cab seperately) you can fry your amp.
Last edited:
A 4 ohm and an 8 ohm cab yields an overall 2.66667 ohm load when in parallel (most common). The 4 ohm cab will get twice as much power as the 8 ohm cab.
In addition to getting answers here, there are various online that you can use to check your understanding and run other scenarios
Example https://geoffthegreygeek.com/calculator-speakers-in-parallel/#jumpto
Example https://geoffthegreygeek.com/calculator-speakers-in-parallel/#jumpto
Yep.
Determine how much power the amp can make at 2.67ohms. Divide the total available power by 3. This is the power available to the 8 ohm cab. Multiply by 2 and you get the power available to the 4 ohm cab.
Just because you can doesn't necessarily mean you should. What cabs are we talking about? What amp?
What cabs are you considering using? Because in some circumstances that can be a savvy way to pair your cabs, and in other circumstances it can be kinda bad.
For example, if the 4 Ohm cab is two 12" speakers and the 8 Ohm cab is one 12" speaker, each driver will probably receive the same amount of power. That's could be a pretty good setup, assuming the speakers are all compatible and your amp can handle the load. (The Mesa Boogie Subway speakers are designed this way: You can pair the 1x12 (8 Ohms) with the 2x12 (4 Ohms), or the 2x10 (8 Ohms) with the 4x10 (4 Ohms), and so on.)
If you're pairing dissimilar cabs, you may end up with a system where you're effectively only hearing one speaker because the other speaker isn't getting enough power to match it in volume. Or other problems may arise.
Just as @lug says, if you run a 4Ω cab and an 8Ω cab out of the same amp, the 4Ω cab will get twice the amount of power that the 8Ω does. So the 8Ω cab would get about 267-watts and the 4Ω cab would get about 533-watts.
But the important info about combination is that the ohms load on the amp will be 2.67Ω. If your amp is rated at 800-watts into a minimum ohms load of 4Ω, that combination of cabs can ruin your amp. Your amp will produce more heat than it was designed for and interior components can smoke and melt if its protection circuits don't kick in and turn it off first. We used to call that "releasing the magic smoke" and that typically turned your amp into a very expensive paper weight. Once your magic smoke is released, it's really hard to get it back and your amp won't work without it.
If you want to use both a 4Ω and an 8Ω cab together using a parallel connection (industry standard connection) your amp will need to be able to handle a 2Ω load or at least a 2.67Ω load. Otherwise you will damage or ruin your amp.
We used to see the combination of an 8Ω and 4Ω cab more commonly when most amps went down to 2Ω, or at least a lot of amps did. One of the favorite things for Eden users was to run an 8Ω D210XST with a 4Ω D410XLT. That sent twice the power to the 410 cab which had twice the number of speakers. That way, all the individual speakers got the same amount of power. The 8Ω D210XST produced the really low and tighter bottom end while the 4Ω D410XLT had that low-mid hump which sounds so great in the mix. But with class D amps it's not nearly as common to see amps that will handle 2Ω and you really need to be careful about not going lower than the minimum ohms load.
Currently using a mesa subway 800 into a Darkglass 212. I’ll more than likely just get another DG212 but am toying with the idea of getting a 4 ohm 410 of some sort
Ric5
Inactive
- Jan 29, 2008
- 29,772
- 30,452
- Disclosures
- I like 5, 8, 10, and 12 string basses
With those cabs theoretically the 800 watt cab would fail first, if you were running high volume. My concern is your ears may fail before your cabs fail.
JeezyMcNuggles
Inactive
- Feb 23, 2018
- 14,723
- 20,970
- Disclosures
- I suck, but nobody really notices
This can cause phasing issues. Best not to mis-match speaker sizes. At the very least, try b4 u buy.
Assuming your not a Hobbit, adding a second identical 212 in a vertical fashion will bring those speakers closer to ear level and perhaps offer some more definition.
Last edited:
Thats what I’ll likely end up doing. Plus the 212 is incredible light and easy to carry around (a bit more so than the 410). Big fan of those cabs.
