Upgrading AL-III Subs

Thought I'd go ahead and make a quick post about the upgrade we did to Alex's AL-III's the other day.
We took out the stock drivers, and replaced them with JL 10W6D4 drivers.
We had to play around with the wiring a little on the subs, because they are dual 4-Ohm voice coil drivers.

(PROS)
After playing around with them for a while, we opted to run the coils in parallel, dropping the drivers down to 2-Ohms.
We also blocked off the ports in the AL-III's, they seemed to have a better low frequency response.

The sound from the JL drivers is MUCH better in my opinion. Everything sounds about the same until you get down to 50 Hz or so...
then the JL's really start to stand out. The ultra low frequencies really start to growl, compared to the stock drivers both at high volumes, as well as very low volumes.
It's like a small set of "subwoofers" were added to the room, with out messing up the curve.

(CONS)
The 10W6's might not be the perfect drivers to use here... we are going to look for a pair of 10W3's and try those as well.
The problem with the 10W6's is the power handling. They are rated for 500w RMS, which is about 200w more than the ribbons.
So to balance the highs to the lows using a single amp, we have the bass gain on the preamp set to about 2:00-3:00
If and when he bi-amps them, it won't matter at all though.

(OVERALL)
These drivers made a huge difference in the lower frequencies, and made the bass come alive in alot of tracks.
A very worth while test you should try and toy around with !!

Didn't the impedance drop bother you. Are you driving them with Lightstars or Sunfires? Probably not a really good choice for the average Joe. What did the things sound like in series? That should have reduced their sensitivity.

Right... running them in series, the bass was way too quiet vs. the ribbons.
So we went parallel, and the bass came up quite a bit.
The speaker overall is reading 3-Ohms, so it's not really a problem in the end.
Right now they are running on a Lightstar, yes. Later he will have to get his own amps either way.
We'll see what happens with the W3's when we find a set. But for now, these sound VERY nice !!!
Way better than they did with the stock subs !!!!!!!!

I looked at JL Audio & they just didn't reach up into the gap of 100-150 hz (where the ribbons cross over). You're missing some upper bass....

I dono... i ws told by JL, that the W6's and the W7's don't roll off till about 200Hz.
I will call Monday, and get them to run a LEAP sheet for me.

Right... The speaker overall is reading 6-Ohms, so it's not really a problem in the end......

How in the hell are you getting 6 ohms?? Mine are & have always been 4 ohms nominal. Maybe they changed the impedance on the AL-III PLUS models...?

A tad off topic but, where's a good starting place to learn about dual voice coils? I bought a VMPS subwoofer that has dual VCs and I don't want to eff it up by doing something wrong in the connections. Sorry for the hijak!

A tad off topic but, where's a good starting place to learn about dual voice coils? I bought a VMPS subwoofer that has dual VCs and I don't want to eff it up by doing something wrong in the connections. Sorry for the hijak!

Dual voice coil subwoofers are becoming a popular choice among car audio enthusiasts who want more flexibility in wiring their sound systems. While typical subwoofers have a single voice coil, dual voice coil (DVC) subwoofers use two separate voice coils, each with its own connections, mounted on one cylinder, connected to a common cone.
Rockford Fosgate subwoofer Rockford Fosgate's DVC subs can handle lots of power for creating bigger bass.

The key difference between single and dual voice coil subwoofers is the multiple wiring options DVC subs offer:

* Parallel: A dual 4-ohm voice coil subwoofer with its coils wired in parallel presents a 2-ohm load to your amplifier. Since an amplifier produces more wattage at a lower impedance, the parallel connection ensures you'll get the most output from your amp. In the same fashion, if you have a stereo amplifier and two DVC subs, wire both subs for 2-ohm impedance (one per channel) for maximum output.
* Series: Series wiring lets you configure multiple woofers to one amplifier at an acceptable impedance. Wire both coils in series for an 8-ohm impedance, and then wire two 8-ohm subs together in parallel for 4-ohm total impedance (perfect for most 2-channel amps bridged to mono operation). Another example: if you have a high-powered 2-channel amplifier, wire four 8-ohm subs per channel (each channel sees a 2-ohm load).
* Independent: You can wire each voice coil to a separate channel of your amplifier, if you prefer not to bridge your amp. Independent wiring is a nice option if you're wiring two DVC subs to a 4-channel amplifier — one voice coil per channel.

Gary, this thing has 2 sets of binding posts, and the previous owner said that he used the L output from a stereo amp(home type-110v) for 1 set of BPs and the R output for the other set. I also got the amp, a Phase Linear that was produced after Jensen took over. I just thought that if both channels weren't exactly matched for output power, and in sync, that the coil might be "fighting" with itself.

These are "woofers" and most bass is pretty much in sync (i.e., mono). It's the same thing that you are doing when you press the mono switch, just at a lot higher power. It would be a perfect way to get subwoofer output out of a stereo only receiver.

Here is a bunch of info on wiring the JL drivers. It will be the same info for any dual coil driver.
http://mobile.jlaudio.com/support_pages.php?page_id=163
http://mobile.jlaudio.com/support_pages.php?page_id=145

Sorry Gary... it's about 3 Ohms. typo

Great links and info Toymaker !!! Thanks

This is the setup I use in my truck.

I was correct....

I spoke to one of the engineers at JL today.
He said that JL stopped posting frequency curve response charts, due to the fact, that there were such huge differences based on the enclosure people were building, that nothing would be accurate unless you built the exact same box they ran the curve off of.

Good news is... (based roughly on all new JL drivers W3, W6, W7 series)
between 80Hz and 150 Hz, there is less than a -.5db drop, and you won't get to a -3db drop off, till you hit 400Hz.

So no, there are no missing frequencies between 80 and 150Hz at all, and I do not hear any volume change between 50 -150 Hz at all.

I will however be looking for a set of 10W3's just to play with, and try out

This is the setup I use in my truck.

Gary, maybe I'm not reading this right but in your diagrams the top one labeled "Series/parallel" is not series at all. It is a straight parallel connection. Both + terminals connected together, ditto - terminals.

In the second diagram you have direct shorts with both + & - ternminals connected together.

So my question is WTF?