I just bought these jbl speakers, they should rock

[srt8-in-largo]

^^^ These 2 posts are GOLD... at least for someone like me who doesn't know too much in this area.

[53driver]

I looked at their specs on http://www.sonicelectronix.com/item_12267_JBL-P562.html
Some things you might want to consider.

The speaker impedance is rated at 2 ohms. Not a big problem for amplifiers that are capable of operating with 2 ohm loads. The OEM speakers are like 3.8 ohms. I know that I tried , as a comparison, running the 2.7 ohm speakers I used with the OEM amplifier and you could tell the OEM amp was running out of steam. Just a thought. You're asking the OEM amplifier to powere a 2 ohm load and I'm not convinced it will like it.

As far as water proofing, the material construction is stated as woven glass so you may be ok. Just wouldn't be directly spraying them down with a hose.

I'm pretty sure you're going to need an adapter or make an adapter to install 5.25" speakers. The stock speakers are like 6" . They have a mounting bolt pattern that is the same as most 6.5" speakers, but the frame is narrower. Some have installed 6.5" speakers and trimming the speaker frame down to fit.

Another consideration is the clearance behind the speaker. The stock speakers have a very small magnet. I don't know the type of magnet, but the Polk Audio MM series component speakers I installed have a neodymium magnet which are small because of the Neodymium magnets. Neodymium is more expensive than traditional magnets.

Just some things to consider. Hope it works out great for you.

2 Ohms is quite a load - that why they can boast the power rating they do.
1. I would make sure that the amp is capable of a 2 Ohm load. Not sure where to find that out.
2. Do not daisy chain these speakers in parallel- that would give you a 1 Ohm load and will in all likelihood blow the amp.

So some quick "Weapons of Math Destruction:"
To get a 2 Ohm speaker to 55 Watts, that requires a 3.7 amp current at 10.4 Volts.
To get a 4 Ohm speaker to 55 Watts, it only requires 1.85 amps but 14.8 Volts - much less of an amp requirement.
To get an 8 Ohm speaker to 55 Watts, it takes less than 1 amp, and 21 volts.
Obviously the amplifier must be up to task for 2 Ohm loading.
If an amplifier at "full-tllt-boogie" is driving two, 2 Ohm speakers to 55 Watts, not counting electrical losses, that's a 7.4 amp requirement on the bike's electrical system.
I do not know what the OEM spec amp is capable of, even though the Fuse Box has a 40A fuse in the "External Amplifier" slot - don't know if that's the Sound System or something else.

I guess my recommendation is get all the info you can and just be careful.
JimmyTee has very valid points as well. Neos are very lightweight and pack a punch.

[Jimmytee]

2 Ohms is quite a load - that why they can boast the power rating they do.
1. I would make sure that the amp is capable of a 2 Ohm load. Not sure where to find that out.
2. Do not daisy chain these speakers in parallel- that would give you a 1 Ohm load and will in all likelihood blow the amp.

So some quick "Weapons of Math Destruction:"
To get a 2 Ohm speaker to 55 Watts, that requires a 3.7 amp current at 10.4 Volts.
To get a 4 Ohm speaker to 55 Watts, it only requires 1.85 amps but 14.8 Volts - much less of an amp requirement.
To get an 8 Ohm speaker to 55 Watts, it takes less than 1 amp, and 21 volts.
Obviously the amplifier must be up to task for 2 Ohm loading.
If an amplifier at "full-tllt-boogie" is driving two, 2 Ohm speakers to 55 Watts, not counting electrical losses, that's a 7.4 amp requirement on the bike's electrical system.
I do not know what the OEM spec amp is capable of, even though the Fuse Box has a 40A fuse in the "External Amplifier" slot - don't know if that's the Sound System or something else.

I guess my recommendation is get all the info you can and just be careful.
JimmyTee has very valid points as well. Neos are very lightweight and pack a punch.

The 2 ohm load was my first concern. My experience with the OEM amplifier is that it didn't like a 2.7 ohm load let alone a 2 ohm load. You have to also consider that these impedance ratings are with the cone at zero. As soon as the cone/driver moves the impedance changes and can often dip well below the nominal rating when the cone is at full excursion.

[53driver]

The 2 ohm load was my first concern. My experience with the OEM amplifier is that it didn't like a 2.7 ohm load let alone a 2 ohm load. You have to also consider that these impedance ratings are with the cone at zero. As soon as the cone/driver moves the impedance changes and can often dip well below the nominal rating when the cone is at full excursion.

Jimmytee - do you know if that 40A fuse is for the OEM amp?

Edit: Just found it - yes it is.

[Jimmytee]

There is a 40 amp fuse for the OEM amp. I don't believe it pulls anything close to that. The wiring on that circuit is 14 awg at best. I know I tried to power my new amp using that circuit , just to see. No good. The amp must have been getting quite a voltage drop across that small wire because the performance suffered considerably. I ran separate or new power and speaker wires for my installation. I did use that 40 amp circuit for the trigger to turn on the new amp though.

[smokinjoe187]

There is a 40 amp fuse for the OEM amp. I don't believe it pulls anything close to that. The wiring on that circuit is 14 awg at best. I know I tried to power my new amp using that circuit , just to see. No good. The amp must have been getting quite a voltage drop across that small wire because the performance suffered considerably. I ran separate or new power and speaker wires for my installation. I did use that 40 amp circuit for the trigger to turn on the new amp though.

i had the same concern being the amp needed a 40 AMP fuse,what gauge wire did you run?
i'm running either 8 gauge or 10,i can never remember

[53driver]

Okay, I did some phone calling....and I have reason to believe it's true, and you will never see this number published, but the OEM amp could only be 8 Watts a side.
No wonder they can get away with 14 gauge wire!
Putting in "55 Watt" speakers won't get you any more volume unless the Sensitivity is higher than the OEM speakers.

Thread relevancy: So these JBLs have a rated Sensitivity of 91dB.
Let's assume that the amp CAN run a 2 Ohm load (big assumption).
For the same amount of Volts and current that the OEM amp is capable of producing, if the Sensitivity of the OEM speakers is 88dB or less, you should hear one "noticeable" volume increase. For each 3dB difference in Sensitivity, there will be a noticeable increase.

More data:
When the average human ear detects an increase or decrease in sound pressure, that's a 3dB change.
Each 3dB increase requires a doubling of power.
I doubt the OEM speaker sensitivity rating is below 88.

Jimmytee - you measured the resistance on the OEM speakers and they were 4ish?
So the amp at 8 Watts into 4 Ohm speakers is about 1.4 amps and 5.7 Volts per side.
Into a 2 Ohm load, that would try to hit 16 Watts with the same amp and voltage. Something is going to give out...and do it unceremoniously.
Conclusion: this amp is only rated at 8 Watts into 4 Ohm speakers, I wouldn't think about putting in 2 Ohm speakers.

Bottom line: I NEED to upgrade this system on my bike.

[Jimmytee]

Someone had posted somewhere they had heard or read that the OEM amp was rated at 80 watts per channel. My testing calls BS on that one. No way is the amp that powerful. Looking at the OEM amp though, it is fairly hefty. 8 watts x 4 is hard to believe as well. What I can tell you is that I'm pushing probably roughly 80 watts per channel up front and the difference in output is substantial . As measured with a sound pressure meter.

[53driver]

Someone had posted somewhere they had heard or read that the OEM amp was rated at 80 watts per channel. My testing calls BS on that one.

80? No way. I know 80 Watt sound. This ain't it.

[stroguy]

Few thoughts:

2. Anything above 15KHz is usually inaudible to anyone over 40 years old,

I'm 50 and I can't see some keyboards.

Good information here.....thank you gents.