Can someone please help with Amp
Thread Starter
Pro
Joined: Oct 2006
Posts: 747
Likes: 0
From: San Antonio Texas
Can someone please help with Amp
Okay simple question. How and the heck do u get a 4 channel amp down to 2 ohms?
At 4 ohms my amp is 55w x 4 and at 2 ohms it is 75 x 4. I know how to drop on a sub but how do u do this on 4 channels?
Please help.
At 4 ohms my amp is 55w x 4 and at 2 ohms it is 75 x 4. I know how to drop on a sub but how do u do this on 4 channels?
Please help.
Le Mans Master
Joined: Jun 2004
Posts: 5,572
Likes: 4
From: Los Angeles Ca
hey man, you are pretty confused on impedance (measured in ohms)
this is something i wrote up in the c5 faq. maybe it'll help you get a grasp on the whole concept:
basically, the only way you're going to get 2 ohms is either find a coaxial speaker that is rated at 2 ohms (there is one out there) or wire up two sets of 4 ohm speakers per chan.
these both are not ideal for your situation, the best bet for you is to return the amp and purchase an amp that can put out the power you want at 4 ohms.
this is something i wrote up in the c5 faq. maybe it'll help you get a grasp on the whole concept:
I have 4 speaker terminals on my sub...what gives?
This is called a dual voice coil sub (dvc) these subs configurations are very popular due to their flexibility in multi sub set ups. So how do you wire them up? Well you have to first find out what impedance (measured in 'ohms') your amp is stable to (note: the minimum impedance of a bridged 'channel' is usually double that of the minimum impedance of the separate stereo channels.
Most dvc subs are either 2 ohm per voice coil or 4 ohm per voice coil. Now you have three options to wire the two voice coils; in series, in parallel or to separate channels.
SERIES: This will 'add' the impedance of each voice coil. So if you have two 2 ohm voice coils wired in series it will equal a 4 ohm load. To wire them in series you'll take one of the positive speaker terminals on one of the voice coils and wire it to the negative terminal on the remaining voice coil. That will leave you with two 'open' terminals: a positive and a negative, wire them to the respective terminals on the amplifier.
PARALLEL: To figure out the final impedance of the speaker you will take the impedance value (2 ohms) and divide it by the number of voice coils (2). so if you have two 2 ohm voice coils wired in parallel you'll have a speaker with a final impedance of 1 ohm. This will cause most of the current amplifiers to go into protection mode and shut off when there is a strong bass hit. To wire the speaker in in parallel connect all the positive terminal to the positive terminal on the amplifier and likewise with the negative.
For an example, My 3-channel Xtant amplifier is stable to 2 ohms on channel 3. My sub is a dvc 4-ohm sub that i wired into a parallel to appear to the amp as a 2 ohm sub. (which my owners manual says is ok/recommended)
keep in mind that this can be applied to multiple subs as well. here is a link to some cool illustrations and calculators.
http://www.bcae1.com/spkrmlti.htm
This is called a dual voice coil sub (dvc) these subs configurations are very popular due to their flexibility in multi sub set ups. So how do you wire them up? Well you have to first find out what impedance (measured in 'ohms') your amp is stable to (note: the minimum impedance of a bridged 'channel' is usually double that of the minimum impedance of the separate stereo channels.
Most dvc subs are either 2 ohm per voice coil or 4 ohm per voice coil. Now you have three options to wire the two voice coils; in series, in parallel or to separate channels.
SERIES: This will 'add' the impedance of each voice coil. So if you have two 2 ohm voice coils wired in series it will equal a 4 ohm load. To wire them in series you'll take one of the positive speaker terminals on one of the voice coils and wire it to the negative terminal on the remaining voice coil. That will leave you with two 'open' terminals: a positive and a negative, wire them to the respective terminals on the amplifier.
PARALLEL: To figure out the final impedance of the speaker you will take the impedance value (2 ohms) and divide it by the number of voice coils (2). so if you have two 2 ohm voice coils wired in parallel you'll have a speaker with a final impedance of 1 ohm. This will cause most of the current amplifiers to go into protection mode and shut off when there is a strong bass hit. To wire the speaker in in parallel connect all the positive terminal to the positive terminal on the amplifier and likewise with the negative.
For an example, My 3-channel Xtant amplifier is stable to 2 ohms on channel 3. My sub is a dvc 4-ohm sub that i wired into a parallel to appear to the amp as a 2 ohm sub. (which my owners manual says is ok/recommended)
keep in mind that this can be applied to multiple subs as well. here is a link to some cool illustrations and calculators.
http://www.bcae1.com/spkrmlti.htm
these both are not ideal for your situation, the best bet for you is to return the amp and purchase an amp that can put out the power you want at 4 ohms.
Thread Starter
Pro
Joined: Oct 2006
Posts: 747
Likes: 0
From: San Antonio Texas
Okay thanks that what i thought. I understand how to hook up subs, but didnt really understand the regular 4 channels. I got a good deal on a Memphis 5 channel so I cant take back. Thanks for your help though.
