4 JL speakers, 1 JL 300/4 amp, and only 2 wires???

I'm adding 2 more JL speakers to my tower, so I'll have a total of 4! I was going to pull the factory amp, JL M2150, and install my JL 300/4 amp! Would it be OK to bridge the JL 300/4, and wire the 4 speakers in parallel? Or is there a better way of wiring them with out running another set of wires up the tower?

Is that OK on the amp? It says when its bridged its 150 watts at 3 to 8ohms! Aren't the tower speakers going to be 2 ohms if i run them the way i described?

depends on the impeadance of the tower speakers. If they are 4 ohm speakers then you could run them in a series/paralell configuration. Wire each "set" of speakers in series, then run the two series sets in paralell and you end up back at 4 ohms and an acceptable resistance to the amp.

the speakers are the jl components. I belive they are 4ohm! If I ran them in a series how much power would be runnning to each speaker at that point?

A JL amp produces the same power at 2 or 4 ohm load, at least this is what I was led to believe.

so which way should i run the speakers parallel or series?

Argh.... paralell and series. I guess I should draw a picture, but......

-each pair of speakers: wire them in series
-now, take the two sets of series speakers and wire them in paralell to the two wires out of the tower.

Does this make sense? This will give you a single channel 4 ohm load that you're amp can handle.

I'm really sorry, but i'm lost! is ther any way you could draw this out for me?

The amp is rated 3 ohm to 8 ohm bridged. It wouldn't be ideal to run a 2 ohm load, but honestly, if you have a separate subwoofer, and don't run any bass to the tower speakers, then the amp should be fine.

I didn't see any impedance curves on their website, but what you will generally find is the low impedance point tends to be just above the resonance tuning in the low frequencies. Upper frequencies tend to have higher impedance, which should be no problem for the amplifier.

To make a long story short, I would do it if I wasn't running any bass to the speakers, if I was running the speakers full range, I probably wouldn't do it. I'd either find an amp with 2 ohm bridge capability or use two amps.

BTW what will generally happen if you run an amp below its impedance rating, is it will get really hot.

Is running 4 wires not an option?

if i have to run 4 than i will! thanks for the help!

With a JL you could run parallel or series I don't think it really matters.

That amp is a turd IMO, there's alot better out there for cheaper. Your not gettign the most our of those speakers with that amp.

The amplifier does not know the difference between a 4 ohm load on each channel and an 8 ohm load on a bridged channel. Electronically the load is identical.

To accomplish this you just need to wire the speakers in series in the tower then hook the two wires to the amp as shown in the manual for bridged operation.

Good call mikeski!

If you are running the speakers full range do it as Mikeski suggested.

yes, i want them to run full range! will I lose alot of volume, when i run them in a series?

call JL (tech support) directly....they will recommend you not wire in series, they can explain why.

w/o going into science behind it you will lose volume running in full range. IT's an easy test....flip the switch back and forth on the HP/FULL/LP corssover on the amp...the HP will soudn the "loudest". FULL will sound the best.

I emailed JL, they said there would be no problem if i ran the speakers in a series! They said each speaker would receive 75watts! Aren't the speakers going to be running at 8ohms? Does that effect the sound quality, or how load they can get in full range?

Woudl you mind pasting that email on here. I'm surprised to hear them say that. Typically why they don't advise running in series is if one of the resistors fails running in series you run a risk of damaging the other speaker or amp. Running in parallel you don't have the risk. This is due to the power running thru one speker from + to - then over to the other speakers - to +. I talked with a tech regarding this and wiring their subs, I assumed it would be the same for full-range speaekrs.

FYI...the speakers don't run at 8 ohms. They show the amp an 8 ohm load.

Techically you should gain a tad SQ by running at 8ohms, but nothing you would be able to tell. Dont forget the environment your in.

Jose Rodriguez <jose.rodriguez@jlaudio.com> wrote:

What you have been told is not true, wiring speakers in series or parallel only changes the impedance the amplifier sees that’s all. By wiring the speakers as I suggested you can bridge the amp and get 150 watts per side. Basically each speaker will get 75 watts.


on 1/23/07 12:55 PM, Ryan Booker at rrbooker@yahoo.com wrote:



I've been told that i won't get a good full range of sound if i wire the speakers in a series! Is that true? What would the ohms and watts to each speaker be, if i wire them in a series? 8 ohms, and 75 watts? Sorry to keep bugging you, i just want to make sure i don't screw anything up!!

Jose Rodriguez <jose.rodriguez@jlaudio.com> wrote:



If you want to save time all you need to do is wire the speakers in series and bridge the amp. Don’t wire the speakers in parallel and also bridge the amp that will cause an unwanted condition for the amp.


on 1/23/07 11:21 AM, Ryan Booker at rrbooker@yahoo.com wrote:




I'm not sure I'm following what you wrote me back. Are you saying i should run another set of wires up the tower? Will I get better sound from the amp/speakers if i run them off all 4 channels?

There is going to be a total of 4 speakers on the tower! I have only 2 wires running up the tower right now. I was going to bridge those 2 wires, so there will be only 2 wires running 4 speakers! how do I want to connect 2 speakers to one wire? if you can send alittle sketch that would be great!



Thanks for getting back with me so soon!




Jose Rodriguez <jose.rodriguez@jlaudio.com> wrote:




Hello Ryan
All you need to do is run each speaker to its respective channel and get 150 watts per side the same as if you were to bridge the amp.

Sam (wake1823) Wrote:

"Woudl you mind pasting that email on here. I'm surprised to hear them say that. Typically why they don't advise running in series is if one of the resistors fails running in series you run a risk of damaging the other speaker or amp. Running in parallel you don't have the risk. This is due to the power running thru one speker from + to - then over to the other speakers - to +. I talked with a tech regarding this and wiring their subs, I assumed it would be the same for full-range speaekrs. "

If by resistor failing you mean speaker failing (since the speaker is the resistor in this case, even though it is significantly more reactive than a resistor), if it were to fail short, you would actually be much better off in series than in parallel. In parallel the amp would blow up or shut down due to the short across the outputs. If the speaker were to fail open, the other speaker would cease to work in a series set up, but there would be no damage.

Also, the way you described running in series is incorrect (btw current "runs", power dissipates). You should wire the negative terminal of one speaker to the positive terminal of the other speaker, not negative to negative (they would be running out of phase in that case).

If you run it the way Mikeski suggests in a bridged configuration then with this amp you will get 150 x 2 at the 8 ohms. The way the slash series amps work is that there is no gain in output by bridging speakers. In a bridged configuration, 3, 4, 5 ,6 7, or 8 ohms, you will always only see the 150 x 2. 75 watts to each speaker, (if you dont get technical). IMO there are better amps, but 75 watts will push those things pretty good, if you want to wake them up, use a different amp that will push about 100-125 per speaker.

What amps would you suggest?