Bi Amp Ohm load

tderks

When using a Bi-amp configuration on an RTi 12 what is the nominal ohm load for each amp.

tderks

I have been reading in another post that external crossovers should be used. My thoughts were that each amp would not "see" the load since the speakers have active crossovers.

Eric W

8 ohm highs, 8 ohm lows.

Eric W

tderks wrote: »

I have been reading in another post that external crossovers should be used. My thoughts were that each amp would not "see" the load since the speakers have active crossovers.

You wouldn't use external (or active) crossovers in this configuration- the speaker's internal crossovers are still in line. This is "passive biamping".

In order to do active bi-amping with an external crossover you'd have to disassemble the speaker, remove its passive speaker network and power the components directly. This usually isn't done unless you're a die-hard tweaker/hard core audio enthusiast.

tderks

I am using the crossovers inside the speakers and the amps see full range. thanks for the info.

They sound great with a Adcom 555II on the bottom and a Adcom 5800 powering the high end.

tderks

If the Ohm load is 8 Ohms Hi and Low when bi-amped, then shouldn't the speaker be 4 Ohms when the jumpers are installed for a RTI 12? I know that a static Ohm load is not what the amp my "see".

mrblkberry32

tderks wrote: »

If the Ohm load is 8 Ohms Hi and Low when bi-amped, then shouldn't the speaker be 4 Ohms when the jumpers are installed for a RTI 12? I know that a static Ohm load is not what the amp my "see".

Hello, I have a pair of rti-12's n these speakers r 8 ohms if ur bi-amping them high n low ur sending a 4ohm load to one amp high n 4 ohm load to the other amp low that's y u have almost souble ur power depending on ur amp n how muxh power its generates to a 4ohm load

mrblkberry32

tderks wrote: »

When using a Bi-amp configuration on an RTi 12 what is the nominal ohm load for each amp.

Hello I have a pair polk rti-12's n these speakers r 8 ohms when bi-amping ur high see a 4 ohm load ur low amp see a 4 ohm load n almost double ur power depending on how much power ur amps can produce n a 4 ohm load my amp is 300 watts per channel rms @ 4 ohms n 400 @ 2 ohms even though rhese speakers r power hungry 300 watts per channel of clean power n high current is enough.

nguyendot

mrblkberry32 wrote: »

Hello I have a pair polk rti-12's and these speakers are 8 ohms when bi-amping. The high section sees a 4 ohm load, while the low section sees a 4 ohm load. This almost doubles your power depending on how much power your amps can produce in a 4 ohm load. My amp is 300 watts per channel rms @ 4 ohms and 400 @ 2 ohms even though these speakers are power hungry 300 watts per channel of clean power and high current is enough.

See how a little grammar would really help out your post? Seriously.

Second, you are not doubling your power. Do you REALLY think the high section will use anywhere near the power the low section will use? It's simple mechanics, bass units move more air and will require more power.

klennop

So am I reading this correctly?

If you just run power to the bottom speaker poles of say an A9, the amp will see it at a 4ohm load?

Hence the same goes with if you are just powering the tops, your amp will see a 4ohm load.

If you have the speaker poles joined by the gold connections which now links the top and bottom speakers and now they are getting power from just one source, your amp will see an 8 ohm load.

Jed Leland

Hello,
The speaker's impedance will remain the same no matter how many amplifiers you connect to it or how many speaker wires you use between the amplifier and the speaker. The speaker's impedance is a result of the components used in the crossover, the loading of the enclosure and the characteristics of the tweeters, mid-range drivers and woofers. Not, how it is connected to the amplifiers that power it.
Cheers, Ken

klennop

There are 2 crossovers in the A9's aren't there? One of the speaker poles connect to the top speakers using one crossover. Then the bottom speaker poles power the woofers on a different crossover right?

So what is the impedance of those crossovers?

If they are 8 ohm, doesn't it work like wiring speakers? Such as wiring in parallel 2 8ohm crossovers that go to speakers, wouldn't the amp see a 4 ohm load?

When the speaker terminals are linked in the back of the speakers via the gold bars, is that not wiring the top and bottom in parallel?

dorokusai

It's 8ohms for either set of binders when in the bi-amp configuration. The loudspeaker is designed in every way shape or form as 8ohm nominal.

Jed Leland

Hello,
There isn't a parallel connection because the crossover isolates each section of the speaker from the other. If an incoming sound were 100Hz, for example, the low pass section of the crossover would present a low impedance to that particular frequency. When the high pass section of the crossover "sees" the 100Hz signal it presents a very high impedance to that frequency and the sound doesn't reach the speaker components connected to this high pass section. If the incoming sound were 10,000Hz the opposite happens. The low pass section of the crossover has a very high impedance to this frequency and the signal never reaches the woofers. But, to the high pass section of the crossover 10,000Hz is welcome and is given a very low impedance. So the internal components only "see" the frequencies that the impedance of the crossover present them. They aren't connected in parallel but isolated from each other by the crossover. The only way you can change the speaker's impedance is by changing something that makes up the load character itself; put in a different tweeter, or different driver or seal a vented enclosure or change the values of the components used in the crossover. If you connected another complete speaker in parallel with the amplifier, yes the load changes. But not with one speaker connected to one amplifier.
Cheers, Ken

Mcaletz

Im getting tsi 300, I want to bi amp them for their depth of sound; Im in the process of searching an amp to drive those speaker. This is where my mind is, 2x150watt@4ohms amplifier, can I use one amplifier per tsi 300 bi-amped. Or do I need 2x150watt@8ohms amplifier for that to be successful. Im not sure if Im on the right track with searching for the amplifier for these speakers. I mean one tis 300 is 150watt@8ohms if I bi-amp it does that split the watts and ohms?