adding a horn and driver
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Posted on May 07, 2010 09:38 pm
rayss
Member Since: Mar 04, 2009
i am thinking of adding a horn and driver to a guitar cabinet to use as a pa main for vocals, does that make sense.
if the horn and driver is 8 ohms does that mean the the cabnet has to be 8 ohms or can it be 4 ohms.
ofcourse i dont know about electronics and will take it to a professional to do it i just dont wanna waste my time and his.
thanks for your info.
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May 07, 2010 09:48 pm To a Guitar Cab?????
Not really the best thing to do to a cab. The amps built in to a guitar cab will not be able to handle the large bandwidth that a Live PA requires.
And typically, guitar cabs have an open back to them. Which will not project the vocal range. And one other thing will be the output load of the amp. The guitar amp is not designed to have any increase in the ohm load.
Sorry, not really the best idea to try and make a PA cab out of a guitar cab.
rayssMember
Since: Mar 04, 2009
May 08, 2010 10:06 am what if its just an unpowered cab, or do they still have amps, i didnt know that.
thanks for the info, so are the speakers in a guitar cabinet different thanthe ones in a pa speaker enclosure
i have a 4 12 peavey speaker cabinet, basicall just a big wooden box withspeakers in it, no open back no power, i was toying around with it using a mackie 406m and a microphone saying check test and all that, comes through alright, just i know speakers with a horn are better for vocals.
rayssMember
Since: Mar 04, 2009
May 10, 2010 05:48 pm so is it ok to add a horn to something like a passive speaker cabinet
May 10, 2010 07:51 pm Sure. That's not a problem.
rayssMember
Since: Mar 04, 2009
May 15, 2010 11:16 am so if the speaker cab is 4 ohms does the horn and driver have to be 4 ohms or does it not matter if the horn and driver is 8 ohms?
thanks for your time
May 16, 2010 11:57 am Sorry to maybe add to the confusion on this.......... But, it depends.
It depends on weather you are going to be making this a passive box, or an active box.
If you are adding the horn with an internal crossover, then it's a passive box. And then, you need to do some simple math for the total ohm load of the box. So, you can have an 8 ohm horn, with an 4 ohm LF driver. There is no law stating that you can not do this.
The only thing that you need to do, is add both ohm loads, then multiply the two ohm loads. Then you divide the two sums to find the total ohm load.
Lets say that you have an 8 ohm horn. And that your LF driver is a 4 ohm load. You then take 8 + 4 = 12. Then multiply the two. So, 8 x 4 = 32. Now divide 12 into 32. The answer is 2.6. This is the total ohm load of your box.
Is 2.6 a good ohm load to have for a box? Not really. Most amps do have a 2 ohm load rating. But, this does not allow you to add any other boxes to that side of the amp. By adding another bos to the amp you will be reducing the amount of resistance yet again. And the amp will go to clip very easily at this point. Which could burn your amp up very quickly.
On any horn that you are looking to purchase. Run this equation before you buy. And this will help to ensure that your amp and box will have a little longevity.
Now, if you are going to make an active box, then it not really an issue. Since an active box uses both sides of the amp to run just one box. So, channel one of the amp goes to the LF driver. And the other channel goes to the horn. For this set up, you need an external crossover to send the correct frequencies to each driver.
rayssMember
Since: Mar 04, 2009
Jun 08, 2010 09:37 am thanks for the info.
yes its gonna be a passive box, it is 4 ohms, so what ohm should the horn and driver be?
thanks again.
rayssMember
Since: Mar 04, 2009
Jun 08, 2010 09:51 am also lets say i do end up with 2 ohms rating and wanted to add another box would it be ok i;m using a powered mixer with two amps and and connect the other box to other amp?
Jun 08, 2010 02:11 pm NO! Anything below a 2 ohm load might as well be a dead short! It will blow up your amp.
rayssMember
Since: Mar 04, 2009
Jun 08, 2010 09:20 pm thanks if i use it ill just use it alone if i end up with 2 ohms, i have a 4 12 enclosure that is rated 4 ohms, if i add a horn what ohms should it be so i end up with 4 or 8 ohms if possible.
thanks.
