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Ohms FAQ
- Thread starter IvanMike
- Start date
Glockenklang sells a transformer that will convert a 4 ohm load to 8 ohms (and vice versa), see "impedance transformer 600" under accessories:
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sounds like you'd be losing some watts somewhere along the way with that transformer. also, how much does it cost???
My understanding is that it is approximately 95% efficient, i.e. if your amp delivers 200 watts into an 8 ohm cabinet and 400 watts into a 4 ohm cabinet, and you used an 8 ohm cabinet with the impedance transformer then you'd get about 380 watts to the cabinet. It might be 97% efficient or 93%, I'm not sure of the exact value. I read it somewhere and it was better than what I expected.
The cost of the unit is about $250, with the case and speakon connectors.
would i be able to get a lower watt head like the new GK fusion 550 for example, and also buy a separate power amp to boost volume levels to meet up to my cabinets high watt standards? if so should i be looking into stereo or mono how would i hook it up etc..
better question for a new post but here goes -
you need a head that has a post preamp & eq output to send to the poweramp's input. many heads have a line out, most have a post eq effects send - either one of those can be plugged into a poweramp's input. I use a y cord to hit both inputs of my poweramp when i do this.
If I'm reading this right, it sounds like you want to run 2 power amps into a single speaker cabinet to increase wattage to the cabinet.
DON"T DO THAT.
What Mike said is good if the fusion and power amp would be feeding separate cabinets, or if you are using only the preamp of the fusion.
Just wanted to make sure you aren't using the power output of both amps.
so you're saying i can get however many power amps as long as i just run the preamp of the head not power?
Step back a bit here! Your cab does not have a "requirement" for input wattage from an amp, it has a maximum input wattage :scowl: The Fusion 550 will likely have enough power to damage your 700 watt cab even though it is "rated" to output 500 watts, at burst it puts out around 800 watts.
Never try to run two amps into a mono speaker cab unless you like to BBQ.
Really need help guys.Have a gallien 700rb and am running 2 markbass 102 hf cabs of it.They are 400 watts at 8 0hm each.I was goin to swap the gallien head for a genz benz gbe 1200.Would this work with my cabs the genz is 1000 watt at 4 ohm but cant figure out the puzzle of will it be to powerful or am i doing something stupid here.Really need advice as can only do the trade on wednesday.
should be fine, just listen to the cabinets to make sure you aren't overdriving them. Go check out the FAQ on over and underpowering speakers.
Both cabs won't change, they are 8 ohm cabs rated to "handle" 400 watts. The two together make a 4 ohm "load" to the amp head, the total power they can "handle" together is 800 watts.
You should be fine as long as you don't crank the GenzBenz up real high or use to much low end boost at moderate levels!
Not sure if someone asked this or not, but what would be the advantage to wiring an 8 ohm cab to 2 ohms, even if you had a head that would safely go down to 2 ohms?
Sorry, I'm at work and the search didn't produce the answer and I have run out of time trying to find it in all the posts here.
the advantage is you use more watts and can get a bit louder. so if you have an 8 ohm 4x10 that handles 600 watts and is 8 ohms, but your amp puts out 200 into 8, 350 into 4 or 550 into 2 then by re-wiring the cab to 2 ohms you'll use 550 watts rather than 200, and get about a 4dB increase in volume, which isn't a hell of a lot. Better off getting another cab if you have volume issues.
Not knowing exactly what 4db sounds like, I'll just stick with what I gots!
3 dB is generally considered the minimum increase most people can hear. 4 dB isnt much different. some folks can hear a 1 dB increase, but it's tiny.
