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onewheat
03-02-2012, 12:49 AM
I have an '07 X-15 with the 6 channel and 4 channel JL amps. The 6 channel is powering the 4 cockpit speakers and the other two channels bridged for the sub. The 4 channel is powering the tower speakers. All speakers are 1 speaker per channel (except sub, of course). What I was wondering is - would you get more power (volume) to the speakers if you bridged two channels and then ran 2 speakers in series? It has been a while since I was into this, but if I remember correctly, two 4-ohm speakers wired in parallel would drop the load to 2-ohms and put on two bridged channels of an amp results in higher (near double) the power - but then is this double power then divided between the two speakers, giving the same net effect?

sp00ky
03-02-2012, 02:13 AM
I have an '07 X-15 with the 6 channel and 4 channel JL amps. The 6 channel is powering the 4 cockpit speakers and the other two channels bridged for the sub. The 4 channel is powering the tower speakers. All speakers are 1 speaker per channel (except sub, of course). What I was wondering is - would you get more power (volume) to the speakers if you bridged two channels and then ran 2 speakers in series? It has been a while since I was into this, but if I remember correctly, two 4-ohm speakers wired in parallel would drop the load to 2-ohms and put on two bridged channels of an amp results in higher (near double) the power - but then is this double power then divided between the two speakers, giving the same net effect?

Maybe, but wouldn't you then lose your current setup of separating highs mids and lows. And highs don't need the power that the sub does correct? Are the tower speakers and sub aftermarket?

EarmarkMarine
03-02-2012, 08:44 AM
4-ohm stereo and 8-ohm bridged will produce the identical power.
2-ohm stereo and 4-ohm bridged will produce the identical power.
Halving the load resistance will often produce 30 to 60 percent more power depending on the particular amplifier up to a point. Rarely would you get close to double the power. And,
as you lower the load, efficiency decreases, damping decreases, headroom decreases and distortion increases. Unlike DC bulbs or something elementary, with an amplifier you have a switching power supply which acts like a buffer between the boat's voltage supply and the audio amplifier. As you lower the load the supply voltage sags. Eventually you hit the power supply capacity and you no longer see a power increase as you continue lowering the load. So there are a couple layers of applicational considerations before you can apply Ohm's Law to amplifiers.
onewheat,
You could use more power all around and especially on the tower speakers but you will have to add more amplifier.

David
Earmark Marine

sp00ky
03-02-2012, 03:40 PM
4-ohm stereo and 8-ohm bridged will produce the identical power.
2-ohm stereo and 4-ohm bridged will produce the identical power.
Halving the load resistance will often produce 30 to 60 percent more power depending on the particular amplifier up to a point. Rarely would you get close to double the power. And,
as you lower the load, efficiency decreases, damping decreases, headroom decreases and distortion increases. Unlike DC bulbs or something elementary, with an amplifier you have a switching power supply which acts like a buffer between the boat's voltage supply and the audio amplifier. As you lower the load the supply voltage sags. Eventually you hit the power supply capacity and you no longer see a power increase as you continue lowering the load. So there are a couple layers of applicational considerations before you can apply Ohm's Law to amplifiers.
onewheat,
You could use more power all around and especially on the tower speakers but you will have to add more amplifier.

David
Earmark Marine

So subs and tower have their own amps correct

EarmarkMarine
03-02-2012, 04:52 PM
sp00ky,
Perhaps, but the distribution of channels could go a couple of different ways depending on which amplifier was used to supplement the factory.

David
Earmark Marine

onewheat
03-03-2012, 12:08 AM
I have the M4500 on the tower - 4x80w at 4 ohms - 1 channel per stock JL Audio tower speaker. The M6600 for the cockpit and sub - 6x75w at 4 ohms - 1 channel for each of the 4 cockpit speakers and 2 channels bridged for the sub. I just found a spec page that says 100w per channel at 2 ohms, so it is a 33% increase for halving the resistance. I was thinking it would have been more. I know JL amps are typically rated conservatively, but still, it appears I am better off leaving it wired the way it is, unless I upgrade the amps to something with more power. The JL component speakers are rated for 100 watts RMS continuous/225 watts peak and with the recommended power being between 40 - 175 watts per channel at 4 ohms. So the amps are decent, but could be stronger. Seem about right?

EarmarkMarine
03-03-2012, 08:44 AM
Actually those JL Audio amplifiers are excellent in construction and sound quality. And they are honestly rated (if not conservative) which you can't depend on with all brands. MC is about as generous or even more so in how they equip these boats as compared to other builders. The fact remains that more power is beneficial. Wholesale replacement makes less sense. Addition is more like it if you want an upgrade.

David
Earmark Marine

Thrall
03-05-2012, 01:49 AM
The JL component speakers can handle 150W RMS in my experience.
What you have in the boat is about the best way to wire it. You'll get a little more by parallelling the 2 pair of tower speakers to 2 bridged channels each, but to get teh most out of your current system, add 1 amp.
Use the 6600 for the cockpit speakers. 2 front speakers 1:1, 2 rear speakers bridge 2ch each to them. Use the 4500 for your sub (you could get a 2nd sub now!) and get another dedicated tower speaker amp and get 150W/ch to the tower speakers.
It will really wake the speakers up.