Does bridging 2 channels increase the ohms on the amp?

Question

I have a 60w x4 (4ohms) amp. If I bridge two channels does it become 120w x 2 (8ohms) OR120w x 2(4ohms)???

Answer 1

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Answer 2

No.Let me explain what ohm means.Most multichannel amps are 2 ohms stable per channel until you bridge the channels...then they are usually only stable at 4 ohms.Here are 3 differnt explainations of ohms.

All speakers produce a certain amount of resistance which is what we call "ohms". Think of it this way....Think of a water faucet.Open the faucet all the way...more water comes out.....slightly close the faucet and the water will flow slowly or trickle persay. So lets use the water as an example of the flow of electricity(voltage and/or amps).And the faucet's valve that controls the flow is the speakers ohms(resistance). A speaker at 1 ohm would represent the water faucet being opened or turn up at the maxium or high level which a large amount of water would be flowing.The large amount of water would also represent the amount of power/wattage. Now a speaker that is 8 ohms would represent the valve turned down to a minimum level creating a smaller flow of water or "power" flowing .... Thus,lower ohms on your speakers will create more power to flow from an amp.However ,when dealing with Electricity/amps/voltage/current it creates HEAT.This larger amount of power creates large amounts of heat.This is why amps have "FIN'S" or slats.An amps outer shell is called a "heatsink".Its designed to absorb and dissapate heat. So that being said...Eventually the heat will wear down the amp if its not kept fairly cool.The heat wears down the various electronic components on the circuit board,thus increasing the chances of damage. Hope this helps

"An ohm is the resistance to current flow. Assuming the same voltage potential, a higher resistance will result in a lower current. It can be expressed in this relationship: current = voltage / resistance The reason this is important is because amplifiers can only operate at a certain maximum current before their output transistors melt down. To prevent this current from being exceeded, they specify a minimum resistance (ohm) for the speakers. Any speaker ohm below this usually results in activation of the amp's safety circuit. When you wire more than one speaker to the same amplifier output, it changes the ohms that the amplifier "sees." If you wire the speakers in parallel, the amp sees half the ohms (twice the current). This is the most popular method of wiring because it increases the power output of the amp by 2. If you wire the speakers in series, the amp sees twice the ohms and has half the output. You can wire a single 4-ohm speaker to an amp and the amp will see 4 ohms. However you can wire 2 4-ohm speakers to an amp (in parallel) and the amp will see 2 ohms. This is fine as long as the amp is rated for 2 ohms. For speakers with dual 4-ohm voice coils wired in parallel, it is just like wiring 2 separate speakers together."

"An ohm is an electrcal resistance on an amp provided by the sub/speaker. How you load an amp determines the amount of power out. There is a trade off though, the lower the impedance (ohms) the more power is pushed as well as higher distortion and more heat is generated. The excessive heat will shorten the life of the amp. For best overall performance, it's far better to get a higher powered amp and load it with 4 ohms than a lower powered amp and force it to push more power with a lower impedance (2 or less ohms) load. The other trade off is price. An amp that will handle higher power at 4 ohm will be more expensive. You should always match up RMS (Root Mean Square) watts of Subs and amp per channel as well as final impedance's (ohms). The two main methods of sub wiring are parallel and series and any combination depending on the type of subwoofer (if it's a DVC[Dual Voice Coil]). I have wiring diagrams and other info on my site http://spkrbox1.spaces.live.com" sparky3489