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Posted: Thu Aug 24, 2006 4:31 pm
by two4fifteen
when it says bridged rms thats basically a typo on the woofersetc.com website. that amp is rated at 320w rms at 4ohm, and 480w rms at 2 ohm, as stated on their website below.

http://www.eclipse-web.com/amp/xa1000.html

Posted: Thu Aug 24, 2006 4:32 pm
by SACHEL
so if i did get the 2 ohm cvr 15'' and had the amp @ 4 ohm it would put out 640w? (RMS)

Posted: Thu Aug 24, 2006 4:36 pm
by two4fifteen
What is "Bridging"?

Bridging an amplifier refers to configuring a two channel (stereo) amplifier to drive a single load with more power than the sum of the two original channels combined. For an example, a 100 watt per channel at 4 ohms amp may put out 400 watts(one channel at 4 ohms) after bridging.

There are important things to know about running an amplifier in the bridged mode:
An amplifier running in bridged mode has one output channel to which a load (speaker) can be connected. It is no longer a two channel (stereo) amp as far as input signals and loads are concerned.
If the amp you want to run in bridged mode does not have built in facilities for doing so, you should not attempt to use it in this manner (unless you are thoroughly sure of what you are doing).
If you run bridged amplifiers, you must pay close attention to speaker phasing (see next item). Otherwise, you may have "hollow" or "weak" sound.
You must pay close attention to speaker wiring. The manufacturer will state which terminal is really the "positive" connection when bridged.
The speaker output signals of a bridged amplifier are floating; such connections must never be connected to any grounded device (such as an external accessory power meter, for example). If you do make such an illegal connection, one amplifier channel is basically short circuited (worst case result is a blown amplifier!).
Amplifiers running in bridged mode are generally limited to speakers with impedance ratings of no less than 4 ohms (in other words don't use a 2 ohm speaker load unless the manufacturer specifically allows it).

Bridged amplifiers work basically as follows:
A single input signal is applied to the amplifier. Internal to the amp, the input signal is split into two signals. One is identical to the original, and the second is also identical except it is inverted (sometimes called phase-flipped). The original signal is sent to one channel of the amp, and the inverted signal is applied to the second channel. Amplification of these two signals occurs just like for any other signal. The output results in two channels which are identical except one channel is the inverse of the other. The speaker is connected between the two amplifier speaker output terminals. In other words, one channel "pulls" one way while the second channel "pulls" in the opposite direction. This allows considerably more power to be delivered to a single load.

If we had our perfect amplifier, upon bridging it we would have a single channel amplifier with exactly four times as much power as any one channel of the amplifier in "normal" stereo mode, assuming a 4 ohm speaker load. This is because the effective output voltage available to drive the speaker has doubled as a result of bridging. A doubling of voltage on a given load results in a fourfold increase of power delivered to that load. If we used a 4 ohm load on the perfect bridged amplifier, the output power would be a very substantial eight times the normal stereo single channel 4 ohm output! These numbers should give some clues as to why real world amplifiers cannot meet such expectations. Once again, we are back to limitations of the power supply. In reality, most amplifiers in bridged mode will put out about 3 times the power as any one channel of the amp in normal stereo mode. The fourfold increase cannot be achieved because the power supply is unable to provide the current required for such performance. With 2 ohm loads, the situation is compounded. The amount of current required to drive a 2 ohm load when in bridged mode will tax the amplifier’s power supply to its absolute limits. Not to mention, the output stage may not be able to safely handle the extra heat that will be dissipated.
Bottom line: stay away from 2 ohm loads if you are running an amplifier in bridged mode!

-courtesy of Glasswolf in the FAQ section of CAC.

Posted: Thu Aug 24, 2006 4:39 pm
by two4fifteen
that 640 is another one of those pesky peak ratings that i told you to stop looking at. if you buy that amp and the dual 2 ohm 15" kicker, it will only get 320w rms if wired in series for a 4 ohm load. and that amp isnt 1 ohm stable so you cant wire it in parallel. THE SUB PRESENTS THE LOAD.

Posted: Thu Aug 24, 2006 6:12 pm
by SACHEL
my bad, i dont know why i keep thinkin that. so the eclipse amp is pretty suitting if bridged to the kicker cvr 15'' 2 ohm. how do you get amps bridged?

Posted: Thu Aug 24, 2006 7:09 pm
by two4fifteen
thats a single channel amp. you can't bridge it. did you not bother reading any of the information i supplied. and like i said before, YOU WOULD WANT THE DUAL 4 OHM one if you choose that amp.

Posted: Thu Aug 24, 2006 8:41 pm
by High Society
I ran a single 15" CompVR in a 3 cuft box tuned to 34hz or so. It was nothing compared to the Execution and the TI but for the 500 rms I was giving it, it sounded great.

As for amp look into mono amps, look for one that does 400-600 watts RMS at 2 ohm, or 1 ohm and you should be set.

Sub; for a 2 ohm load get a dual 4 ohm sub: heres how to wire it; http://home.myspace.com/index.cfm?fusea ... 6f738a38ee

For a 1 ohm load get a dual 2 ohm sub: heres how to wire it; http://www.rockfordfosgate.com/rftech/w ... 2+ohms+x+2

Posted: Sun Aug 27, 2006 11:59 am
by SACHEL
if mono amps cannot be bridged then what does it mean for the eclipse xa1000 amp when it says bridged rms 480w
http://www.woofersetc.com/index.cfm?fus ... ct_ID=4619

Posted: Sun Aug 27, 2006 12:19 pm
by two4fifteen
again, you dont listen. i told you earlier in this thread that that is a typo on woofersetc.com's website.


p.s. im really not trying to come off as mean or rude, but having to restate the same point several times gets frustrating.

Posted: Sun Aug 27, 2006 12:44 pm
by SACHEL
oh don't worry, i just take it as me being a dumbass. i was wondering then how then do you switch from 4 ohm to 2 ohm on a mono amp?