tower speakers cutting out.

[Afrodan03]

This is my first post, so i wanna start off by saying whats up to everyone. I have an 07 RZ2 with the Tower of Power sound system. When i bought the boat it only had the 2 kicker tower speakers, but i love my music, so i had the dealer add on 2 more. This is when my problem started. With the volume up around 25-29, the tower speakers will completely cut out. I took it back to the dealer and all they told me was the amp was going into protection mode and that they couldnt do anything. So if anyone has any suggestions, it would be greatly appreciated.

[chpthril]

Odds are the amp is just not "tuned" right and needs to be set properly.

When they added the 2nd pair of speakers, it put a 2ohm load (down from 4 ohm) on the amp. This causes the amp to work harder and run hotter. This will cause the signal to clip or put the amp into protect mode.

Answer a couple of questions for us first: what tower speakers do you have? factory installed Kicker Components or other? Do you have the Kicker ZX350.4 amp? if other, what brand and model.

[buffman]

definately agree, the amp is more than likely to small shoot the specs to us...it unfortuante your dealer isnt more helpful as well, especially for an '07

oh yeah and welcome to one heck of a great site!

[philwsailz]

I am about 95% sure of what is going on.

Don't worry about your dealer's inability to take care of it. You came to the right place! Those guys work on boats; we work on boat stereos. Let them keep your boat running, we will make it sound right.

You have the factory Tige system with two speakers on the tower, right?

The amp that you have is almost guaranteed to be a KICKER ZX350.4 and it is probably wired in 2-channel bridge mode.

When the dealeer added the second pair of speakers, I guararntee they did not run the additional wire through the tower to connect the new speakers properly. They probably added the second set of speakers and wired them so that the positive connections just tied together, and the negative connections just tied together. This causes each amp channel to see a 1-OHM load, which is outside of the amp's capabilities.

Assuming this is true, the system will not run reliably for you, and it will eventually cause the amp to fail. However, the fix is easy!!!!

You have two options:

1. Re-configure the existing speakers and wire such that each speaker pair is wired in SERIES. This will provide a 4-OHM load to each amp channel which is ideal for the amp. I will post a picture of series wiring in a minute; it is easier to understand in a picture.

2. Pull extra wire through the tower so that each speaker has a positive and negative connection straight to the amplifier. There are 4 speakers, and the amplifier has four channels. That is easy to explain! Trick is getting the wire through the tower. Chpthril has done it, and can give some tips. This method provides a 4-OHM load to each channel of the amplifier as well, and is a real easy load for the amplifier to drive.

Regardless my assumptions, please take the time to figure out exactly how it is wired right now, take pictures of the wire at the speakers if it shows clearly how it is wired. Look at the amp. How many individual wires are coming out of the speaker connections at the amplifier, and which connections are they attaced to?

These things will help us in determining for sure what you are up against, and how to make it worl and work well for you.

Once we get the wiring right, we will then go and do the other stuff with the crossover gain, and other settings to maximize things for ya.

I am the marine sales and engineering guy at KICKER so trust me, we will get you going, and going properly!

Welcome to the boards!

[philwsailz]

Here is a crude schematic showing the difference between series and parallel wiring.

If your system is currently wired like the example at the left, (parallel)changing it to the example on the right probalby will get it to quit cutting out.


You have a PM from me, by the way...

Let us know!

[spharis]

What he said. +1

I would use option #1 Phil suggested (diagram #2). You aren't putting that much power to the tower, so the wire size is fine. Two short pieces, a move or two and you are done.

[xpjim1]

Ok Phil, I thought I was beginning to understand this stuff. A few Questions
1) If you bridge the channels is it not only stable in 4 ohm
2) If the speakers are 4 ohm would not running in parallel make them 2 ohm
I am so confused

[philwsailz]

Ok Phil, I thought I was beginning to understand this stuff. A few Questions
1) If you bridge the channels is it not only stable in 4 ohm
2) If the speakers are 4 ohm would not running in parallel make them 2 ohm
I am so confused

Let me try to respond without writing a book.

Answers to question 1:
When we bridge two amp channels together to run a single speaker or load, we need to ADD the minimum load alowed for each amp channel to determine the minimum load for the bridged "section". For example most amplifiers today are rated to operate safely at 2-ohms per channel, and no less, so in bridge mode, we can run a speaker or load at no lower than 4 ohms.
For any amplifier, regardless if it is bridged or not, it is always safe or safer to run the amplifier into a HIGHER load. The current draw is less, and the amplifier will run cooler.

Answers to question 2:

Yes, two speakers that are 4-ohms each will cause a two ohm load when they are connected in parallel.

For any pair of speakersin parallel, regardless of impedance, we can use the following equation to determine the resultant new impedance, simply the product of the two speaker impedances divided by the sum of the two impedances:
S1 = speaker 1 impedance in ohms
S2 = speaker 2 impedance in ohms
Sx = resultant parallel combined impedance in ohms

Sx = (S1 x S2) / (S1 + S2)

In summary, I might ask you to clarify what you are asking in #1, and your understanding of #2 is correct! You are not as confused as you think.

[spharis]

To add some info and up the confusion level. If you think of the speakers and wire as circuits and ignore the fact they are speakers it makes it easier to understand for some reason.

2-4ohm speakers wired in parallel create an overall circuit at 2 ohms (2=(4*4)/8).
This is what he probably has on his tower currently. He has 2 4 ohm loads on 2 circuits. This yields 2 2ohm circuits.

The amp is not stable bridged at 2 ohms. The low resistance makes it too easy for the amp (which always outputs the same power) to send power through the circuit. The power has to go somewhere (energy cannot be created or destroyed) so it transforms to heat by grounding, the enemy of the amp. This causes it to go into protect mode.

It is stable at 4 ohms (forget bridging now and just worry about the fact that you can have particular loads on particular terminals, in this case we need 4 or greater). In order to get the overall circuit to 4 ohms or greater, the speakers can be wired in series. To formulate series load, simply add the impedance of all the speakers or loads together. Series on 2-4ohm speakers makes an overall circuit of 8 ohms. So, in turn this creates an 8ohm load on the amp.
This is what Phil's second drawing shows. This is 2-4ohm loads on 2-circuits. This yields 2-8ohm circuits.

While the 8 ohm load on the amp is not ideal, it will prevent the amp from going into protect mode.

Having an ideal load deals with having the most efficiency of the circuit while being stable. This amp is most efficient and stable by wiring each channel to a 4 or 2 ohm load. It is also ideal by wiring split across 2 channels a 4 ohm load (bridging).

The OPTIMAL wiring for this install with 4 speakers would be 4-4ohm speakers to each (4) channel; this yields the most efficient output at highest level.

Optimal may not be in this installs best interest, so for a quick fix, rewiring to series gets it done.


The OPTIMAL wiring for 4-4ohm speakers to a two channel amp is two circuits of parallel speakers (2pos and 2neg to each terminal) like man of us do. Just like what they tried to do but failed due to the 4 channel amp. Had this been a 2-channel amp, this would have worked ok, albiet at a lower power to each driver.


Interestingly enough the power in each circuit bridged at 8 ohms is going to be about the same as 4 -4ohm channels, so with there being sufficient wire size in each circuit, there really is no point in rewiring another leg to the amp. Take the easy route.

I know it isn't accurate, but wiring grade would look something like this for different loads:
60 watts @ 4-ohms | 100 watts bridged at 4 ohms | 90watts @ 2ohms | 90 watts bridged @ 8 ohms
60 watts per driver | 50 watts per driver | 45 watts per driver | 45 watts per driver

[philwsailz]

Sp-

your comment, specifically:
Had this been a 2-channel amp, this would have worked ok, albiet at a lower power to each driver. is maybe slightly over-simplified, for such a complex post, do you not agree???

Had it been a pair of 4-ohm speakers, connected to a stereo amplifier that was stable to 2-ohms PER CHANNEL....
The addition of the second set would have halved the load, theoretically and mathematically doubling the power. The existing speakers in theory would see the SAME amount of power, with the extra power going to the new speakers.

This is all theoretical of course, and is probably not incredibly relevant, but fun nonetheless...

[spharis]

Sp-

your comment, specifically:
Had this been a 2-channel amp, this would have worked ok, albiet at a lower power to each driver. is maybe slightly over-simplified, for such a complex post, do you not agree???

Had it been a pair of 4-ohm speakers, connected to a stereo amplifier that was stable to 2-ohms PER CHANNEL....
The addition of the second set would have halved the load, theoretically and mathematically doubling the power. The existing speakers in theory would see the SAME amount of power, with the extra power going to the new speakers.

This is all theoretical of course, and is probably not incredibly relevant, but fun nonetheless...

Unless of course it was one of these Kicker amps that has more than double at 2 ohms. Don't get too specific you engineer you!

What Phil is saying is that some amps put out greater than double power at 2 ohms so the statement is not entirely true, but for ease of conversation we'll say it is.

[dogbert]

Somehow after reading this I'm reminded of the discussion of how coconuts could get to England in Monty Python's Holy Grail...

[philwsailz]

hah hah hah!!!!!!!!

Yeah, this topic can get wordy and stratospheric real quick!!!

It always does, every time. Every single time...

I am getting better at shorter responses though!!!! Aren't I????

[philwsailz]

What Phil is saying is that some amps put out greater than double power at 2 ohms so the statement is not entirely true, but for ease of conversation we'll say it is.

Wait a minute....

Not what I am saying... (like most of the rest of us could figure it out either way)..

Theoretically, an amp that has its output load halved will double its power. That is the theoretical max; you cannot get more than double, and I don't know of an amp that will deliver more than 2x power at 1/2 the load.

A Kicker amp does not double its power when you halve its load.

The theoretical doubling in fact does not happen in most amps due to the huge amount of heat that the load creates.

In this case, the probable amp in question is the ZX350.4

Its output scenarios are as follows:
4-channel mode:
60w x 4 into a 4 ohm load per channel
90w x 4 into a 2 ohm load per channel

2-channel mode:
90w x 2 into an 8-ohm load
175w x 2 into a 4-ohm load

Are we all getting more confused?

[philwsailz]

We can confuse about anybody at this point, so getting back to the specific issue, we need to get Afrodan03 to series wire like in the right example in the pictutre above. I agree it is the very best way.

Then we can set his gains and crossovers....