Need your help regarding Amp & Cab

[lebrett]

I will soon buy my first Amp & Cab rig (always used combos before) and I learned a lot about Ohms, Watts, Neo and stuff here on TalkBass. But I still have two unanswered questions.

As of today I look for this setup :
Genz Benz Shuttle 9.0
SWR Golight 4x10 800 watts 8 Ohms
SWR Golight 2x10 Junior 400 watts 8 Ohms

So here are my questions:

1- If I plug those 2 cabs will the cabs watts add up for a total of 1200 watts? In other words will it be safe to run the 900 watts of the Amp to both cabs (4 Ohms) simultaneously?

2- I know the 4x10 alone will handle the 500 watts in 8 Omhs setup but what about the 2x10? If I use it alone and make sure that I don't go crazy with the volume (say for practice or small venue) will it be safe for that cab?

Thanks for your help.

[Bass_Pounder]

Yes - in theory, the two cabs combined will be able to handle 1200 watts. However, the real answer is that since they are the same impedance and getting equal share of the power, you will be limited to 2X your lowest rated cabinet (800 watts).

Additionally, that "rating" is only the thermal rating of the voice coil. The cab will start hitting it's physical limits long before the "rating".

The 2X10 by itself (getting 8 ohms power) will be fine as long as you listen to your speakers, and back off at signs of stress.

I really don't think that the 2 cabs together is a good idea though..............

You will be sending twice the power to the speakers in the 2X10. That cab is going to fart out long before the 4X10 does, so you will be limited by the 2X10's capabilities.

[lebrett]

Thanks Bass_Pounder. But if what you say is right, why Markbass suggest that their 4x10 104HR would go along with 1x15 151HR or even 2x10 102HF?

I understand what you're saying and it makes sense but I read different opinions and I am not sure what to do best.

Thanks.

[Bass_Pounder]

Markbass is in the business of making money - they would highly recommend ANY of their products to you.

Just the fact that they would recommend a 4X10 together with a 1X15 shows they are not really on the ball.

What you asked about will work - just not a very optimal setup.

If you are looking to do a total of 6X10's, you need to have a 4 ohm 4X10 combined with an 8 ohm 2X10. That way all the speakers will be recieving equal power. Just make sure your amp can handle a 2 ohm load.

[aledeville]

800W cab can handle more than a 800W amp. It depends on the sound, playing style, compressor etc. AND a normal solidstate amp rated with 800W is not able to produce 800W... A class d even produces less than the classical solidstate.

But that's not a problem at all. It makes things easier for you. Almost every combination is possible, just listen to the speaker and as soon as it starts to fart (or produce other strange noises) you know that it was too much power.

I support everything Bass_Pounder said.

[lebrett]

Thanks for your answers guys. I am not settled yet on the final configuration. I chose a 4x10 and 2x10 for practical reasons. It seems not to be a wise choice. So I will change for one or two 4x10. Thank you very much.

[RickenBoogie]

Yes, 2 of the same is ALWAYS the better choice, unless you do as mentioned, to be sure all drivers get equal power distrubution.