So, I've been dabbling in car audio for the last 15 years or so and have plenty of experience with a variety of brands. Started with a single JL Audio 10W1, bumped up to a pair of 10W6s, then an Adire Brahma (1st gen), followed by various other brands before settling for a long trend of using only Image Dynamics ID & IDQ series.
Recently I decided to trim down my system and go small, with a single Boston Acoustics GT-40 powering a set of Image Dynamics CXS64 (v1) and an Elemental Designs SQ10 in a stealth installation.
Elemental Designs rates the SQ10 with a power handling of 350w RMS. I think eD was being a bit optimistic. At 240w, and being responsible with the gains the SQ10 would bottom out. I'd say 200w is a safe place for the SQ10 to be and I'd advise a high pass crossover point around 38Hz as it really struggles with anything below that. This was in the proscribed 0.3ft^3 sealed enclosure.
The stealth install looked good and it was nice to have some rear hatch space again for grocery runs but I was underwhelmed by the sound quality and output of the SQ10 so I decided to look at other options. Don't get me wrong, at moderate volumes the SQ10 was fine. Anything close to 'loud' really put the SQ10 to shame.
So, I pulled out my ID12V3, put it in a 1.25ft^3 enclosure and lost most of my rear hatch space. I was very happy with the Boston Acoustics GT-40 so I picked up a GT-22 for a great deal and it powered the ID12 while I looked at other options. I also upgraded my head unit from an Eclipse CD5425 to a CD7000 and decided to go semi-active since the CD7000 has some fantastic crossover capabilities. By'semi-active' I mean running the CX64 mids bandpassed from 80Hz to 3.1kHz and the tweets at 3.1kHz but keeping the NX4 passive crossover in the mix for tweeter protection. Overall I was pretty happy with the way things were sounding, except for the sub. The ID12v3 is a good sub, but not a great SQ sub and after many years of ID & IDQ subs I figured it was time for a change.
I decided to focus on a 10" or 12" SQ subs with a power handling around 500w. The DIYMA was high on my list but I was unable to find one. Considered the W7 and IDMax but they were a bit pricey.
Luckily I ran into an old friend who had a Boston Acoustics G5 12" in a sealed enclosure. He raved out the sound quality and the output. I brought over some of my favorite CDs and took a listen. Very impressive. Tight, loud, accurate, and hit the lows right on target. And it did it with around 500w which was in the power range of my GT-22 when bridged mono.
I did some research and was very impressed with the G5 in terms of specs and it also looked to be a very high quality built sub. Throw in the fact that you can buy soft part replacement assemblies for under $100 and I was sold.
Unfortunately retail on the G5s was a little out of my budget so I kept looking for a good deal and finally found it this weekend.
A local dealer was closing out his Boston Acoustics products because he was dropping the brand from his inventory (bummer for him, great for me).
With size again being an issue for my installation (I drive an '06 Scion xA) I decided to go with a 10". Fortunately he had the G510RS which is a 0.5ft^3 net enclosure with the GTR10 passive radiator tuned at 35Hz.
I've never really seen passive radiators used in car applications but decided to give it a shot, and it was a choice I won't regret.
Boston claims the passive radiator will give you a boost of 3dB with the sub/radiator combo giving a larger moving mass.
The G510RS is a 2ohm load and is rated at 450w RMS which is a perfect match for my GT-22 bridged mono (around 500w RMS). Using Boston's 'QTune' settings I adjusted gains, set high pass crossover at 34Hz, and set the 'Q' to the recommend 1.0 settings (this is a feature on Boston amps, not sure how it would relate to other amps), and did some tweaking.
After listening to some of my favorite CDs I was extremely impressed. Kick drums were tight and could be felt in your chest. Trance bass lines hit hard and true. Popped in some jazz with upright bass and each pluck of the strings sounded dead on. Old skool rap, like NWA, Public Enemy, Dr Dre shook my ride with that sick ghetto bass.
The G510RS has a pretty small footprint. It is wedge shaped with the sub and radiator on opposite sides of the enclosure. I still lose some of my precious rear hatch real estate but it is a compromise I'm willing to make.
During the research phase of my sub search I really came across nothing about the G5 subs. Not many credible reviews aside from a few customer reviews on Crutchfield and SonicElectronix which should be taken with a grain of salt.
I have to give the G5 two thumbs up and would definitely recommend anyone considering a SQ sub to take a look and a listen.
The build quality of these subs is incredible. One of the first things I did after picking up the G510RS was to take it apart to look at the sub, the enclosure, and the adjust passive radiator system. Top notch, and I don't think I've ever seen a sub that looks as impressive as the G5 does.
Another cool thing is that the passive radiator is adjustable by using weights that come with the sub. The have clear instructions on how to tweak the radiator to achieve different tuning frequencies. I was happy with the 34Hz so I left it there but I'll probably spend some time this week tweaking it to see what sounds best in my little xA.
I'm really surprised the Boston G5 series subs aren't talked about more. They simply kick ass
I should probably also comment on the Boston GT series amps. Small footprint, 2ohm mono/1ohm stereo friendly, conservative RMS ratings and great controls. They feature active cooling, a solid heat sink and the internals show excellent build quality. (Take a look at Ampguts.)
Here's a stock photo. I neglected to take pictures of my own sub after taking apart the enclosure. If I get around to it I'll add pictures of the G510RS components, including the G51044, the GTR10 radiator, the tuning system, and the enclosure itself.