dumb question but have to ask
 

on an amp that is 2 channel, that means like running 2 subs, 1 channel per sub at a certain amount of rms? is that correct

Yes. Or only using 1 Ch. is fine too. or bridging the 2 Ch.'s to get the maximum power out of the amp to 1 or more subs, depending on how they are wired.

regards, Mark

Bridging applies only to amplifiers that are brdgeable. That means the sum total power of the amplifier, to one load. Being careful not to deviate from the manufacturers recomendations.

All depends on the amp. Some amps also produce the same power in stereo mode vs. mono. Also a 2 ch. amp can also run many speakers with a passive x/o setup.

Mark Bruno

ill try to lay it out the way i look at it.

the number of channels an amp has is how many diferent signals it can recieve.

a 2 channel amp can recieve 2 different channels. for example A front left signal and a front right signal is the most comonly used but if you realy wanted to ( just an example) you could run 2 right channels.

i dont like to say a 2 channel amp runs 2 speakers ( or subs ) as the number of speakers you can run on 1 channel of an amp is infinite as long as the amp can handle the final ohm load.

which is why i liek to stick with my first explination as it to me is the most accurate.

Wiring Subs and Bridged Mono
 

And if you don't know what bridging or running a 2-channel amp as 1-channel summed mono means...here's a brief explanation:

Usually, a typical amp's left positive terminal becomes the positive speaker wire terminal for one channel bridged operation, and the right negative becomes the negative speaker wire terminal for the bridged mode...so the left negative and right positive terminals are not used at all. (Please check your owners manual, on some amps this is in reverse).

The trick comes when you run in bridged mode but wire both (or multiple) woofers together and run them off that one bridged channel.... There are at least a couple of ways of doing that, too.

First is SERIES WIRING, where the amp sees impedance of the subs summed together. This is an easier workload for the amp and does not produce as much power as Parallel Wiring will (unless the amp (Like a JL) has heavily regulated power supply in which case it produces pretty much the same power no matter what the load is).

For example, if they are 4 ohm subs, the amp is seeing 4 + 4 = 8 ohms in bridged mode, which is the same load on the amp as running the amp in 4 ohms stereo. Series Wiring is a bit tricky in that it's not intuative...

1). Attach a positive wire from the positive bridged terminal on the amp and wire it to the positive terminal of the first sub.
2). Attach a wire to the negative terminal of the first sub and wire it into the positive terminal of the next sub.
3). Attach a wire to the negative terminal of the last sub, and run that to the negative bridged terminal on the amp.
4). You're done!

Second is PARALLEL WIRING, where the impedance when using two subs is halved from what one sub would be, causing the amp to run at lower impedances...this can be very dangerous for amps not designed to handle low impedances and will cause overheating and ultimately failure of the amp. As the impedance falls lower, the amp has to work harder and as a result often will produce more power in this configuration. It is perfectly fine to run in this configuration as long as the amp is designed to handle the higher load of low impedances. (Counter-intuative again, low impedance = high load for the amp). So two 4-ohm subs in Parallel would give you a 2 ohm load, which is the same amount of work for the amp as running at 1-ohm stereo.

To wire up in Parallel:
1. Run a wire from the positive terminal of the first sub to the positive terminal of the second sub.
2. Run a wire from the negative terminal of the first sub to the negative terminal of the second sub.
3. Now, wire the positive bridged terminal from the amp to the positive terminal of either sub, and a negative bridged terminal from the amp to the nagative terminal of the same sub.
4. You're done!
(You can do a different version of this by running two wires from the one positive bridged terminal....attach one to the positive speaker terminal of each sub. Then repeat by running two negative wires from the negative bridged terminal on the amp...attach one wire to a negative terminal on each sub).


There are so many ways of wiring up subs, and it can get pretty complicated when you have say 4 subs, each with 2 voice coils....and you can then wire up the coils in any manner you wish to try and present the amp with a load that it's designed to oprate the best at. Say for example you have an amp which can handle 1.5-ohms in bridged mono mode, and you have 2 subs each w/dual 6-ohm voice coils. You would wire up each sub's vc's in parallel to cause each sub to sum out at 3 ohms, and then parallel both subs together, ending up at 1.5 ohms.

OR, you could run the amp at 6 ohms bridged mono by first wiring each sub's 6 ohm vc's in parallel to sum at 3 ohms, and then Series Wire both subs together 3 + 3 = 6 ohms.

Last option is to Series Wire all four VC'c together 6 + 6 + 6 + 6 = 24 ohms...not practical, so you'd never do it with these kind of subs but some competition SPL subs have 1-ohm VC's, so in such a case the amp would see a 4-ohm bridged mono load at the amp terminals, equivalent to running the amp at 2 ohm stereo.

Hope I didn't confuse you...:) Main thing to remember, Match your amp's design and capability with the load you present to the amp and how you wire up the subs. That's why some amps are better suited to driving a certain set of subs than other amps even if the other amp is rated for more power...Amps like to live and do perform best in their comfort zone...and the bonus is your amp will be playing music for a long time that way.

You confusificated me.

Can you run that by me again in simpler terms? :P

he is not talking about an amp itself. but how to wire speakers to get a certain load .

if you just wanted to know what a 2 channel amp is then look at my description.

if you want to know how to get a certan load to yoru amp ( ie 2 , 4, 6 ohms ) his post will help you out. or jsut go here for pictures and a clearer understanding

http://mobile.jlaudio.com/support_pages.php?page_id=145

RedZone,

My reply was aimed squarely at islandphile in jest.

I think his explaination was really well written.

Adam

what do you know, nOOb?