ohms and other meditational states!!

[thunderider]

ok this is doing my crust in!! my last post wasnt very clear,basically i have an 150 watt pa? amp,i was running 115 and a 212 untill it started making horrible noises,wich i now belive its clipping,with either it sounds ok,but am running the 212, im just wondering what i can run from both chanels,here are the numbers
amp....150w....4 ohm minimum impedance
1x12.....8 ohm 30 watts 40hz
1x12.....6 ohm 30w.....40 hz
they are celestion g12h from a park 412,yet the blown one i have has 15ohms on it??,are these mismatched,ive wired them paralle,should i wire serial to change the ohmage???

the 15 has no makings on it it came from a fal 100w combo but that has no info on that either.
also have i made a mistake as iv bought a laney 150w head thinking this may be better as its actually a bass head and not just a pa amp? would linking these 2 together give me 300 watts being able to drive my both cabs?? i thought this rock n roll was easy!!

 

[Bass_Pounder]

The 12's are guitar speakers, NOT bass speakers.

And yes, they are mismatched - wiring the 2 of them together gets you a 2.9 ohm load (below the 4 ohm minimum of the head).

Honest opinion - sell/trade/dump everything you have now, and save up for a proper bass rig.

 

[thunderider]

so im better off just using the 15 then? so when i get the laney what would be the best configuration?

 

[Bass_Pounder]

Only if the 15" is a bass speaker, and mounted in a properly sized and tuned cab.

Anything else is a recipe for disaster !

 

[thunderider]

yea the 15s a proper bass speaker its from a 100 watt fal combo infact its still in the combo box i just removed the dead head,what would be good to go on a 150 head a 2x10??

 

[Bass_Pounder]

yea the 15s a proper bass speaker its from a 100 watt fal combo infact its still in the combo box i just removed the dead head,what would be good to go on a 150 head a 2x10??

First, you need to know the impedance of the 15" before you try to add anything else to the mix.

*IF* you can add more speakers and remain within the minimum specs of the head, then the best pairing would be another 15".

 

[thunderider]

how can i find impedance? or duz it have to go to a shop to be tested?

 

[BassmanPaul]

Get yourself a digital multimeter and measure the DC resistance of the driver. If the resistance is a bit under 8Ω then it will be an 8Ω driver. Under 4Ω and it will be a 4Ω driver.

 

[thunderider]

ah ha disconnect the wiring and put a 12 thro each output speratly!!!

 

[Bass_Pounder]

ah ha disconnect the wiring and put a 12 thro each output speratly!!!

They are still very low wattage guitar speakers though..........

 

[thunderider]

if i replace theses what would be best??

 

[Bass_Pounder]

if i replace theses what would be best??

That would depend upon the size of the box, and the tuning.

Making a speaker cab is not as simple as just throwing some of the "correct size" speakers in a box.

 

[thunderider]

no i ment just replace the cab with a properly built one such as laney or summat....just junk the cabs i got and buy some off ebay