Mixing Different Cabs With Different Ratings

[Ruck]

So basically I was wondering if its ok to combine:

500w amp at 2 ohms,

4x10 250w cab at 4 ohms,

2x12 600w cab at 4 ohms.

My main rig is down and I have a medium/large venue to play without PA support! 500w is abit overkill and I dont need all that volume but 250w on its own will fall a tad short of moving enough air.

Is this going to put alot of stress on the 4x10 250w cab?

Ta for looking, opinions and experience needed please!

[chris_b]

You'll be OK putting an amp rated at 250 watts into a cab rated at 250 watts. I doubt you'll be running the amp flat out so it won't really be 250 watts. The cab will be safe.

You'll have more people telling you you shouldn't run the 2 cabs because the speakers are not the same size, but if it sounds ok to you, do it.

Let us know how it worked out.

Edited March 28, 2013 by chris_b

[Mr. Foxen]

Speakers not being the same size isn't the issue. Its all over the specs of the cabs being different. There is a lot more scope for things going wrong with two cabs, if one is a bunch louder than the other, it can mask the sound of the other farting out, and being damaged. Plus a cabs impedance is only a nominal figure, at certain frequencies most power could be going to one cab because it has a lower impedance than the other. It isn't about watts, because watts aren't a useful specification.

[xgsjx]

You can run both cabs from that one amp, but like Mr F says, there's more important variables than watts (tolex Vs carpet is probably higher up on the importance scale ).

I'd be tempted just to go with the 2x12.

[JTUK]

The only thing that I don't like about the plan is the 250w 410. That is a very low output figure and suggests very old chassis; imo,,,
in which case I wouldn't trust them running loud or hard.
That apart, the plan would normally work pretty well.

[BassTractor]

Skinny:
1) Read Mr. Foxen's answer five times
2) Take the 212 if it sounds good or loud. Take the 410 if that one sounds good or loud.
3) EQ down the bass frequencies.
4) Success!


There may also be (considerable) differences in the cabs' efficiency, and you might find the 410 is louder. The 212 has less cone surface, and would need larger excursion.
Chances are it's less efficient. Can't know this though.

Another thing is the difference between 250W and 500W is not that much

Also, it's unclear whether the amp's specification says it gives 250W into 4 Ohm. OK if you know this, but if not, it might just be more. Not that it would play an important role though.

Edit: I seem to have deleted an important aspect:
Your punch through in the mix is in your overtones. The human ear can "hear" the fundamental even if it's EQ'ed out. The fundamental needs way more excursion and thus Wattage than the overtones. So it's a good idea to EQ down the lowest frequencies when in a situation like this. I'd rather do that than to combine two unknown cabs.


best,
bert

Edited March 29, 2013 by BassTractor

[Ruck]

Ok thanks people, Im going to test using just the 2x12 at tonights gig which is a smaller venue. Its an old Epifani 212UL which weighs a ton!! funny as I thought UL meant ultra light.