12 tweeters from one amplifier, how did he do that?

[RXdriver11 2]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

[Duran 387]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

Current follows the path of least resistance, so if impedance is the same, power is divided equally

[RXdriver11 2]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

Current follows the path of least resistance, so if impedance is the same, power is divided equally

So.... for sake of convo does that mean that 10 speakers (4 ohm) wired together to 1 1000W (@ 4ohm) amp will see 100w per speaker?

[Duran 387]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

Current follows the path of least resistance, so if impedance is the same, power is divided equally

So.... for sake of convo does that mean that 10 speakers (4 ohm) wired together to 1 1000W (@ 4ohm) amp will see 100w per speaker?

If total resistance is the same, including wire, and you wire to 4 ohms nominal, yes.

[RXdriver11 2]

That clears some things up for me.. and helps me in deciding my options for a frontstage amp too.

[NB50 206]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

Current follows the path of least resistance, so if impedance is the same, power is divided equally

So if I have 7 4ohm speakers 3 in series and 4 in series then those lines parallel they all receive the same power.

[helotaxi 46]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

Current follows the path of least resistance, so if impedance is the same, power is divided equally

So if I have 7 4ohm speakers 3 in series and 4 in series then those lines parallel they all receive the same power.

No, but I think that you knew that. The voltage is equal across each major parallel segment of the circuit. The current is constant through each series portion. Fairly simple math using Ohm's Law can give you the power to each load in the circuit as long as you know the load and voltage and how it is all wired together.

BTW, 12 tweets on a single amp is completely stupid and could not have sounded like anything other than noise. That said, back in the day, Speaker Warehouse (JL Audio) built "the Blazer" that had 37 speakers including 8 10w5s wired to a single PPI 2-channel amp. It won 4 consecutive IASCA titles IIRC.

[RXdriver11 2]

ok.. im a little bit more confused. I need a little bit more dumb down explanation.

[NB50 206]

I know this is an old post but if anyone can explain the power that each speaker will see in the example from SM's tahoe. I understand that many speakers can be hooked up to one amp if the ohm's are stable but how do you figure the power??

Current follows the path of least resistance, so if impedance is the same, power is divided equally

So if I have 7 4ohm speakers 3 in series and 4 in series then those lines parallel they all receive the same power.

No, but I think that you knew that. The voltage is equal across each major parallel segment of the circuit. The current is constant through each series portion. Fairly simple math using Ohm's Law can give you the power to each load in the circuit as long as you know the load and voltage and how it is all wired together.

BTW, 12 tweets on a single amp is completely stupid and could not have sounded like anything other than noise. That said, back in the day, Speaker Warehouse (JL Audio) built "the Blazer" that had 37 speakers including 8 10w5s wired to a single PPI 2-channel amp. It won 4 consecutive IASCA titles IIRC.

Yes I know, just a little ribjabbin.

[NB50 206]

ok.. im a little bit more confused. I need a little bit more dumb down explanation.

Sorry if I confused you a bit, give me a little bit and I'll draw up an example of both : even # of speakers on parallel legs and odd # of speakers on parallel legs.

[NB50 206]

These are very simplistic examples, there is a lot more to it but it gives the example of power distribution.

In circuit one there is four 4 ohm speakers in series on each branch of the parallel circuit.

that would give you 16ohms per branch with two wired in parallel it presents a 8 ohm load to the power source.

Using ohms law E=I*R, E = voltage, I = current, R = resistance

120v/8ohms = 15A. There is 15 amps of current being provided to the circuit. Being that both branches are 16 ohms you can easily see that there is 7.5 amps per branch 120v/16 = 7.5A. So taking the 7.5A per branch you can calculate the voltage drop for each load 7.5 * 4 = 30V. Four loads of 30V voltage drops = 120V (voltage drops must add up to supply voltage). So each load in the circuit is droping the same voltage and seeing the same current so they are seeing the same power P=V*I, 30*7.5=225W each speaker is receiving 225W.

In circuit 2 there is four 4 ohm resistors in parallel with 3 4 ohm resistors.

Branch of four = 16 ohms the branch of 3 = 12 ohms paralleled together = 6.85 ohms. So 120V / 6.85ohms = 17.5A in the total circuit. Branch with 4 loads = 120 / 16 = 7.5A of current for the branch. With 30V of voltage drop over each load each load is seeing 225W in the branch with 4 loads.

Branch with 3 loads = 120 / 12 = 10A of current, so 10A*4ohm = 40V of drop. 40V * 10A = 400W of power to each driver.

I may have missed something but I dont think I did.

[helotaxi 46]

I may have missed something but I dont think I did.

Looks right to me.

[RXdriver11 2]

First off happy holidays to you guys. and i appreciate all of the help and knowledge you guys are teaching the inexperienced like myself.. ok.. so right now im running 1 10" Fi Bl (dual 1 ohm) in series to a RF 1500bd cp @ 2 ohms. So its getting close to 1800w (per the birth sheet) so if i decided to add a second and wire it series/parallel down to 1 ohm does that mean that the birth sheet 1800 something w that the amp gives at 1 ohm will be divided equally? (so each sub will get 1800 something divided by 2)

[Impious 1,476]

First off happy holidays to you guys. and i appreciate all of the help and knowledge you guys are teaching the inexperienced like myself.. ok.. so right now im running 1 10" Fi Bl (dual 1 ohm) in series to a RF 1500bd cp @ 2 ohms. So its getting close to 1800w (per the birth sheet) so if i decided to add a second and wire it series/parallel down to 1 ohm does that mean that the birth sheet 1800 something w that the amp gives at 1 ohm will be divided equally? (so each sub will get 1800 something divided by 2)

If your current sub is wired to 2ohm, then it's not getting 1800w, it would be receiving half of that.

And yes, if you wire two subs of the same impedance together they will each receive half of the power.

[RXdriver11 2]

First off happy holidays to you guys. and i appreciate all of the help and knowledge you guys are teaching the inexperienced like myself.. ok.. so right now im running 1 10" Fi Bl (dual 1 ohm) in series to a RF 1500bd cp @ 2 ohms. So its getting close to 1800w (per the birth sheet) so if i decided to add a second and wire it series/parallel down to 1 ohm does that mean that the birth sheet 1800 something w that the amp gives at 1 ohm will be divided equally? (so each sub will get 1800 something divided by 2)

If your current sub is wired to 2ohm, then it's not getting 1800w, it would be receiving half of that.

And yes, if you wire two subs of the same impedance together they will each receive half of the power.

so what you are saying is that its receiving the 1800 total (900 each voice coil)??

[Impious 1,476]

First off happy holidays to you guys. and i appreciate all of the help and knowledge you guys are teaching the inexperienced like myself.. ok.. so right now im running 1 10" Fi Bl (dual 1 ohm) in series to a RF 1500bd cp @ 2 ohms. So its getting close to 1800w (per the birth sheet) so if i decided to add a second and wire it series/parallel down to 1 ohm does that mean that the birth sheet 1800 something w that the amp gives at 1 ohm will be divided equally? (so each sub will get 1800 something divided by 2)

If your current sub is wired to 2ohm, then it's not getting 1800w, it would be receiving half of that.

And yes, if you wire two subs of the same impedance together they will each receive half of the power.

so what you are saying is that its receiving the 1800 total (900 each voice coil)??

No, your current sub is not.

It is receiving 900w (based on your 1800w figure), with each voice coil receiving half of that. So 450w to each voice coil, 900w total to the sub.

When you get a 2nd sub and wire to 1ohm, then each subwoofer will receive 900w, 1800w total to the pair.

The amplifier outputs power based on the final impedance of the connected load. 2ohm final load (two 1ohm coils in series) equals 2ohm power output (around 900w @ 2ohm based on 1800w @ 1ohm). That power is then divided equally to each individual load (in this case with 1 subwoofer, each voice coil, since each voice coil is the same impedance).

[RXdriver11 2]

First off happy holidays to you guys. and i appreciate all of the help and knowledge you guys are teaching the inexperienced like myself.. ok.. so right now im running 1 10" Fi Bl (dual 1 ohm) in series to a RF 1500bd cp @ 2 ohms. So its getting close to 1800w (per the birth sheet) so if i decided to add a second and wire it series/parallel down to 1 ohm does that mean that the birth sheet 1800 something w that the amp gives at 1 ohm will be divided equally? (so each sub will get 1800 something divided by 2)

If your current sub is wired to 2ohm, then it's not getting 1800w, it would be receiving half of that.

And yes, if you wire two subs of the same impedance together they will each receive half of the power.

so what you are saying is that its receiving the 1800 total (900 each voice coil)??

No, your current sub is not.

It is receiving 900w (based on your 1800w figure), with each voice coil receiving half of that. So 450w to each voice coil, 900w total to the sub.

When you get a 2nd sub and wire to 1ohm, then each subwoofer will receive 900w, 1800w total to the pair.

The amplifier outputs power based on the final impedance of the connected load. 2ohm final load (two 1ohm coils in series) equals 2ohm power output (around 900w @ 2ohm based on 1800w @ 1ohm). That power is then divided equally to each individual load (in this case with 1 subwoofer, each voice coil, since each voice coil is the same impedance).

so @ 2 ohm my sub is only receiving 25% of the rms from the amp?

[Impious 1,476]

What?

No.

It's receiving 100% of the amplifiers 2ohm power output (assuming you have the gain set correctly), which is probably 900w @ 2ohm.

Ohms law. You should review these before you ask anymore questions.

Read Me 1

Read Me 2

[NB50 206]

Impious, RF isn't doing the normal rating scheme, they are rating full power (1500W) into both 2ohm and 1ohm.

http://www.rockfordf...en_US&p_status=

[Impious 1,476]

Impious, RF isn't doing the normal rating scheme, they are rating full power (1500W) into both 2ohm and 1ohm.

http://www.rockfordf...en_US&p_status=

Don't mind me.....just sleeping at the wheel.

I missed he said he had the Constant Power amps

Then yes, I fucked up. Your sub is getting the 1500w (1800w if you go by the birthsheet) right now, with half of that going to each coil.

Wired to 1ohm, each sub would receive 750w (900w if you go by the birthsheet)

[RXdriver11 2]

What?

No.

It's receiving 100% of the amplifiers 2ohm power output (assuming you have the gain set correctly), which is probably 900w @ 2ohm.

Ohms law. You should review these before you ask anymore questions.

Read Me 1

Read Me 2

ok im even more confused. I read this site often trying to understand thing better but it always confuses me, that why i come to the forums.. its rms @ 2ohm is just under 1800w (i used whole number for simplicity) and the gains are set with an O scope..

[Impious 1,476]

Like I said, I missed that you said you have the "Constant Power" amp.

So yes, at 2ohm your amplifier is outputting 1800w to the subwoofer.

At 1ohm the 1800w will be divided equally between the subwoofers.

[RXdriver11 2]

Like I said, I missed that you said you have the "Constant Power" amp.

So yes, at 2ohm your amplifier is outputting 1800w to the subwoofer.

At 1ohm the 1800w will be divided equally between the subwoofers.

dude thanks for putting up with my stupidity.. i think i figured it out in idiot terms. I think my best bang for the buck would be to get another single BL (dual 2) and wire that puppy parallel which would show a 1ohm to the amp. now just to be sure that i am learning if i were to do that setup would that sub see the 1800w each coil or 900 each coil (wired parallel)?

oh yeah the birth sheet says 1153 @ 4 ohm, 1739 @ 2 ohm, and 1890 @ 1 ohm

BTW the only reason im asking is because i want to push that thing to the limits (gained down a little of course). right now my current BL (10" dual 1 in series) is in 1.3 cubes with 15sq in port area and sounds pretty good.. but I want great. i want to get all out of it that i can and it seems like it is currently being underpowered with the series configuration. so i figured i could purchase 1 more dual 1 add those 2 together and wire it parallel for a total 1ohm and still get close to full output from my amp.. just looking at what my available options are..

Edited November 29, 2010 by RXdriver11

[helotaxi 46]

You will not hear one bit of difference between the dual 2 sub and the dual 1 sub that you currently have UNLESS the new sub is also larger, there simply isn't a big enough difference in power between the 1 and 2 ohm power of that amp. To get a real difference you either need to increase cone area of the single driver or go with a pair of drivers. The pair will likely net you the biggest gain since it is the option that will reduce power compression and actually increase the efficiency of the individual drivers.

[Impious 1,476]

dude thanks for putting up with my stupidity.. i think i figured it out in idiot terms. I think my best bang for the buck would be to get another single BL (dual 2) and wire that puppy parallel which would show a 1ohm to the amp. now just to be sure that i am learning if i were to do that setup would that sub see the 1800w each coil or 900 each coil (wired parallel)?

oh yeah the birth sheet says 1153 @ 4 ohm, 1739 @ 2 ohm, and 1890 @ 1 ohm

BTW the only reason im asking is because i want to push that thing to the limits (gained down a little of course). right now my current BL (10" dual 1 in series) is in 1.3 cubes with 15sq in port area and sounds pretty good.. but I want great. i want to get all out of it that i can and it seems like it is currently being underpowered with the series configuration. so i figured i could purchase 1 more dual 1 add those 2 together and wire it parallel for a total 1ohm and still get close to full output from my amp.. just looking at what my available options are..

I think the part I bolded in red was a typo?

Like helotaxi said, the subwoofer being wired in series won't have anything at all to do with it being underpowered. And the difference between the amplifier's 2ohm power output and 1ohm power output is completely negligible and inaudible.

Also as helotaxi pointed out, you'll actually get slightly better performance out of each subwoofer if you purchase a 2nd dual 1ohm BL and run 2 subwoofers. In theory, adding a 2nd driver without increasing power would yield a 3db gain (keeping the alignment the same as well).....but you are probably experiencing fairly signficiant power compression with 1800w on a single driver. Adding a second will decrease the power to each subwoofer which will decrease power compression, which is a good thing. It would be possible for you to actually increase peak output by more than 3db due to the decrease in power compression, which robs the driver of output for a given amount of power input.