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i dont really understand bridging of speakers and amps. if i connected 2 subs together and the one sub into channel one of the amp lets say its 8 ohms each sub does that mean each sub will be getting 4 ohms? Also if i have different 4 ohm subs and wanna keep them at 4 ohms and bridge them to get more power is there a way to do it without connecting the 2 cause my amp doesnt go into 2 ohms

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Very simple.

 

You read specs.

You see the bridge amp as a single amp.

You use regular ohm calculations, i.e. 2x8ohm=4ohm, 2x4ohm=2ohm etc.

You respect minimum load of the amp.

Each cabinet with same ohmage gets half the power delivered by the amp under that particular load.

 

That's it.

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i dont really understand bridging of speakers and amps. if i connected 2 subs together and the one sub into channel one of the amp lets say its 8 ohms each sub does that mean each sub will be getting 4 ohms?

 

Two 8 ohm subs on one channel present a 4 ohm load to the amplifier. Two 8ohm subs will split/share the 4 ohm output of the amp channel.

 

 

Also if i have different 4 ohm subs and wanna keep them at 4 ohms and bridge them to get more power is there a way to do it without connecting the 2 cause my amp doesnt go into 2 ohms

 

 

When bridging you connect the load (your sub) to the 1+ and 2+ terminals, assuming you set the dip switches properly, this effectively "bridges" the power of the two separate amp channels together. If you have two 4 ohm subs, the only way to not present a 2 ohm load to the amp would be to only connect one sub to each bridged amp. Only very good and generally more expensive amps can handle a 2 ohm load when bridged.

 

Read and then reread the manual. And, what Agedhorse said! Winston

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I think it important to know that running dual mono and bridging are different things. I ran across a band last weekend that claimed they were bridging so I took a look and all they did was run a jumper from input 1 to input 2. They said they were bridging because they only needed one feed to get signals from both sides of the amp. I didn't try to correct them because that would have been a disaster waiting to happen.

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I think it important to know that running dual mono and bridging are different things. I ran across a band last weekend that claimed they were bridging so I took a look and all they did was run a jumper from input 1 to input 2. They said they were bridging because they only needed one feed to get signals from both sides of the amp. I didn't try to correct them because that would have been a disaster waiting to happen.

 

 

Good point, generally those who get into this kind of trouble also don't recognize proper terminology.

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Do any "pros" still bridge since 8kw amps are readily available now? I think it is just the amateurs that still bridge
:lol:
.

 

You know that is a good question? Guess its a lot cheaper to bridge than buy 6, and 8K amps. You better find a really good circuit or two to hook up a couple of big boys like that.

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If you don't understand this, you do not want to bridge your amp.

 

 

I guess in the end if your smart do you really want to be pushing your speakers that hard? Its like boat diesels to me. With no turbos or small ones the damn things run forever. Put big turbos and you go fast but get 1/3 the life.

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You know that is a good question? Guess its a lot cheaper to bridge than buy 6, and 8K amps.

Peaveys' new 6k amp (shipping soon) is being quoted at under $500 :eek:.

You better find a really good circuit or two to hook up a couple of big boys like that.

Not true - an Itech 8000 draws about the same as an RMX4050 as it is about 2x as efficient. A bridged RMX2450 driving two 8 ohm loads draws about the same as a RMX5050 running two 8 ohm loads in stereo - in both cases putting about the same power into a pair of 8 ohm cabs.

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Peaveys' new 6k amp (shipping soon) is being quoted at under $500
:eek:
. Not true - an Itech 8000 draws about the same as an RMX4050 as it is about 2x as efficient. A bridged RMX2450 driving two 8 ohm loads draws about the same as a RMX5050 running two 8 ohm loads in stereo - in both cases putting about the same power into a pair of 8 ohm cabs.

 

I'm sure your right. I havent gotten use to these new amps yet. Still using my boat anchor amps until they die I guess. I can justify buying new amps at least not yet.:cry::cry::cry::

 

If these new peaveys deliver and are reliable I guess we will all be saying goodbye to 25 to 60 pound amps.

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A bridged RMX2450 driving two 8 ohm loads draws about the same as a RMX5050 running two 8 ohm loads in stereo - in both cases putting about the same power into a pair of 8 ohm cabs.

 

 

Correct.

 

What determines power draw is efficiency (at the power being discussed) x audio output power. As long as everything is done using the same m4easurement technique the numbers will be pretty acccurate. There will be differences as you move between topologies though as efficiencies change with output power from 0% to 100% of output power. A typical class H amp will be 0% efficient at no volume to maybe 50% at full power and will vary NON-LINEARLY in between due to the discontinuities in the tier switching.

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I guess in the end if your smart do you really want to be pushing your speakers that hard? Its like boat diesels to me. With no turbos or small ones the damn things run forever. Put big turbos and you go fast but get 1/3 the life.

 

 

First off, you're not necessarily pushing the speakers any harder, you're pushing the amp harder. The speakers don't care if they see bridged power or stereo power, only if they see too much power.

 

The other equation is the harder one. Better to buy a more expensive amp to run in stereo or bridge a lower priced one and accept the likely shorter lifespan? How much shorter? Is there a right answer?

 

Winston

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First off, you're not necessarily pushing the speakers any harder, you're pushing the amp harder. The speakers don't care if they see bridged power or stereo power, only if they see too much power.


The other equation is the harder one. Better to buy a more expensive amp to run in stereo or bridge a lower priced one and accept the likely shorter lifespan? How much shorter? Is there a right answer?


Winston

 

 

Provided the amp is designed for the load, and of like quality, there should be no difference between stereo and bridged operation UNLESS there are problems like shorted speaker lines, which tend to be more catastrophic under bridged mode operation.

 

Really, the biggest problem is with folks that do not understand what they are doing and end up overpowering speakers because they do not understand the specs and how they apply.

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Provided the amp is designed for the load, and of like quality, there should be no difference between stereo and bridged operation UNLESS there are problems like shorted speaker lines, which tend to be more catastrophic under bridged mode operation.


Really, the biggest problem is with folks that do not understand what they are doing and end up overpowering speakers because they do not understand the specs and how they apply.

 

 

I was under the impression that running an amp in bridged mono mode is harder on the components than stereo operation whether or not it is designed for it....

Is that wrong for say our QSC PLX level of amplifier?

 

Winston

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I was under the impression that running an amp in bridged mono mode is harder on the components than stereo operation whether or not it is designed for it....

Is that wrong for say our QSC PLX level of amplifier?


Winston

 

 

The voltage levels are lower and the current is higher. It's a tradeoff. Provided that the amps are designed to similar benchmarks, the difference will be almost zero.

 

There are some valid schools of thought that say bridged amps are more reliable because voltages are quite lower.

 

But there are other schools of thought that say there are twice as many components in a bridged amp making them twice as likely to have a failure.

 

But there are the mechanisms that are used to achieve higher powered amps in stereo that add additional failure risk (class G/H).

 

But there's the common thread that when bridged amps face a shorted load they tend to fail more readily.

 

So when you balance out all the tradeoffs I don't think it's all that clear.

 

I do see a higher percentage of amps in use fail in bridge mode, butthat may be due to improper use, failure of a driver causing the amp to see a shorted load, etc.

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Hey all. Prior to my music days (about 7 years) I was heavily into competion care audio. Sound quality all the way. But I have an amp made run bridged all day long into a 1 ohm load. Or 1/2 ohm stereo. It is an Orion HCCA 225. It is kind of a "cheater amp" because its only rated to 25 x 2 into 4 ohms. But it made to be run into 1 ohm bridged at 400 watts. This was run into 2 10' Orion subs, each with dual 4 ohm voice coils. Parallel everthing to get it to 1 ohms. Ran it that way for 10 years or so. The system had a 36 db/oct low cut at 27 hz and a 12db/oct high cut at 90hz. It was tri-amped with 2 tweeters, 2 mid/woofers and 2 subs. Anyway, just a little aside on the world of bridging and impedance. Rock on everybody.

 

Peace,

Alex

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