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8 to4 ohm

#41
Zigman said:
This is what im doing, im going to 4ohm on the 15 and adding a 210 8ohm on top to kik it down to 2. 6ohm 133wats to the 210 and the rest. Of the 400 gos to the 15
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Zigman, we all wish you the best outcome with your project. Judging from this quoted post, you do not understand how speaker loads work. Also your amp is only good down to 4 ohms. I suggest you read this:

AMPS FAQ!! Info on OHMS, Allsize RIGS-OverUnderPowerCabs DIY TechTalk-Links

Come back and ask questions!
 
#44
And from reading TB in running a 4 and 8ohm 3/4 of the power will go to the 4ohm and 1/3 to the 8ohm so the 210 is rated at 200watts it would be safe at the 133 the amp would be supplying, the rest going to the 15
 
#45
So your 8 ohm 210 and 4 ohm 15 will work. 2.67 ohms. I had a rig like that in the early 90's and used the on-board crossover and a second Peavey head because bi-amping was the cool thing to do back then. Keep in mind there are several BW baskets all with different characteristics. Is your 15 cabinet a 115BX or so? I believe that will have the 1502-DT-8 and you can put the 1502-DT-4 on your magnet and it should perform as designed.
I used one of those cabs not too long ago as a back-up and blew it easily - twice- with an SVT and a 5 string in a rock band at moderate volume. That tells me it's probably good for a not-very-punishing 250 watts.
 
#46
Zigman said:
And from reading TB in running a 4 and 8ohm 3/4 of the power will go to the 4ohm and 1/3 to the 8ohm so the 210 is rated at 200watts it would be safe at the 133 the amp would be supplying, the rest going to the 15
Click to expand...
I might be be completely wrong about this, so somebody please correct me if I am, but isn't this exactly backwards from the way it ought to be done? Doesn't this send most of the power to the single speaker in the 115, while splitting the remaining power between the two speakers in the 210? Wouldn't this be a recipe for blowing the 115 long before you could even hear the 210? The amp doesn't care which cab is 4 ohms and which is 8 -- it sees 2.67 either way -- but your drivers will.
 
#47
Thats not the way i understand it, the amp will deliver 1/3 power to the 8ohm cab and being 1/2 the power rateing or less of the blackwidow it will take less to drive them, and hopefully it will balence out with no danger of blowin the 15 or the 10s
 
#48
Zigman said:
Thats not the way i understand it, the amp will deliver 1/3 power to the 8ohm cab and being 1/2 the power rateing or less of the blackwidow it will take less to drive them, and hopefully it will balence out with no danger of blowin the 15 or the 10s
Click to expand...

The power rating doesn't directly tell you anything about how loud they'll get with a given input level. To suss the sonic balance you need to compare sensitivity ratings for the two cabs, then factor in the power split to the cabs, then maybe look at the frequency response curves of both cabs.
 
#49
So i put the 4ohm bw in my cab and my ears tell me it is louder, and abit clearer, im pleased. My next step is the 210 and then i should be done for a bit? I doubt it its like a never ending thing
 

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