lamar2016

OK, so I have been reading and seeking information about how to get more bass from the back of the system and failed to find an option I liked. I just ordered the Polk Audio MM842DVC 8 inch sub which I will install and hook it up to the current system. I will have to build out a frame for the unit in order to mount it under the rear deck (like the original). The hybrids have a smaller trunk (due to batteries) making a sub box impractical. I will take pictures and have done things like this before with success. I am expecting better performance, however due to the possible power limitations of the Pioneer unit it may not be satisfactory. In this case, I will add a small Amplifier to boost the speaker and see how that works. Last step if the performance is not good is to enclose the sub in a box. I will post plenty of pictures especially if the system sounds really good. This will take several weeks between work, other projects, etc. I will keep you posted. The Polk Audio sub is Marine certified and should have some characteristics that give it a chance to sound much better than the 6.5 inch "sub" that is in the deck now. It does not do much?

Quick update with some pictures. I designed the frame (see attached photos) to mount the subwoofer in the deck. It needed some offset pieces added in the front as the deck has different heights. The frame is designed to fit snug again the bottom of the deck and use the existing bolt holes in place to mount it (the four threaded nuts that now hole the current sub in place). I had to use the router to offset the other screw holes and allow room for the welded on nuts so that the wood would fit snug under the deck. I have cardboard templates for all the dimensions. The sub is now wired and ready to install. It will be a few more weeks until I have a couple of days to install it. I will keep you all posted. I do not have high expectations for performance, however we will see if there is any improvement over the stock sub soon. Also, the Sub is 4 Ohm so I wired it in parallel to get it to 2 Ohms as the original is 2.5 Ohms. Wanted to get close to the original Ohm rating on the stock unit. More to come!





Installed unit


Installed unit wiring hookup

The unit is now installed in the car and working. Able to install with only removing the back seats and lifting the deck up some. Used the factory holes to mount the speaker frame too and utilized sound deadening material as a gasket between the vehicle deck and wood speaker frame. The unit fits very tight and no rattles or ANY problems at all!
Now, here comes the truth of the matter, how much, if any, is the system performance improved? My best estimate, with somewhat limited time to listen so far, is about 15% better. The bass is DEFINITELY better than the stock unit and offers more punch. Overall I am able to adjust the balance one or two levels more to the rear now which achieves a more balanced system. Before, when I balanced to get more sound from the back, the sound quality went down overall. Now, I can play a song with a significant amount of bass, at about a 40 sound level and the sound is impressive. When I watched the woofer cone during the initial tests, it had quite a bit of movement, way more than the stock upside down firing woofer that came with the car. It is, however, limited by the size, lack of a box, and power output of the Lexus head unit. My goal now is to listen to the system for several hours to determine if I am satisfied with the outcome, or if I will add a small amplifier to the system. With the Hybrid, the battery is in the trunk which should make adding one much easier. My first impressions of overall system performance are that I am satisfied and will just enjoy it as is. Last comment, would I do it all over again (given the effort to design, build, assemble, and install the woofer system), likely no. A 15% upgrade in performance versus the effort may not be the best course of action for many ES owners. I sure hope this helps! Anyone who lives in the D/FW Metroplex is welcome to come by and see/hear the system if you would like. Sorry this took so long, and thank you for your patience!!

Moreno0101

I'm planning the same upgrade to my ES300h. The bass roll-off from the head unit is pretty bad at high volume. I think the main issue is the factory head-unit and stock amp (located under the driver seat, I believe). You are still using the same weak signal from the OEM configuration, in this situation, I wouldn't expect much of an improvement. I plan on installing an Audio Control ACM-300.1 amp (175w RMS @ 4ohms) to power an 8" JL audio 8W1v3 4ohm subwoofer rated at 150w RMS @ 4 ohms. I'm going to first try using the same signal from the stock system for the amp speaker level input (same signal you are using) and see if it sounds better coming out of my new amp (the ACM-300.1. Which has a built-in Line output converter and base restoration). If these improvements are not satisfactory I will go under the seat to tap into the speaker signal on the stock amp input. The only issue I have is finding a diagram with color codes for the Stock AMP wires. I just need to find a full range signal (the front/rear door woofer signal). I've searched online for these OEM speaker wire color codes and it has been a challenge. So I hope that I don't have to go this route.

I'll post photos once complete.

Your adapter ring looks awesome BTW, great job!. TBH a 15% upgrade in the bass is nice, the OEM sub output is so muted.

https://www.audiocontrol.com/car-aud...iers/acm-1300/
acm-1.300 retail is $250, i found a almost new one on Ebay for $120 shipped.

https://www.jlaudio.com/collections/...bwoofers-92079
JL Audio 8W1V3-4 Subwoofer is 159.99 new

I'm waiting on a good deal for the sub, prices have been fluctuating recently. All I need is the in-line fuse, battery terminal upgrade and figure out the mounting position of the AMP in the trunk. Im trying to hide the amp so everything looks oem. The amp is so small it could fit almost anywhere.

Thanks for sharing your project.

lamar2016

Hi Moreno:

I was able to listen to the system some more and would now bump that 15% bass improvement rating down to about 8% now. I will look into the ACM-300 Amp you mentioned above as an option to boost the subwoofer performance. Thanks for your insights!!

htxlexuss

Did you use a aftermarket amplifier or just stuck with the oem? I wanted to upgrade my subwoofer and door speakers but not sure if the stock amp can handle it. Would you know how many watts does the stock amp have? I dont want to have to install an aftermarket amp and sub because its too much trouble. Thanks!

htxlexuss

Also can you tell me step by step on how to remove the subwoofer if you dont mind? And what is that piece you made and what is it use for and do i need one?

htxlexuss

One more thing were is the stock amplifier located and how can i get the wire diagram in case i need to tap into the wire for aftermarket amp and sub? Thank you

jallen71

Hey lamar2016, thank you for your detailed posts about the rear sub upgrade. Would you be willing to share the drawing or specs on how you made your adapter ring? Looks like you used wood? I have many tools and a router and probably reproduce one like you made. I have a 2017 ES300h without the ML. I'll double check the 2016 and 2017 rear decks are made the same. Thanks so much for your detailed post with updates. It's very helpful of you.

lamar2016

Hi Jallen:

Sorry for the delay, I do not check this site often lately. I am willing to mail you the cardboard templates if this would assist? If interested send me a mailing address to lynnamartin1@juno.com and I will mail out. Please give me some time as I am busy and work and would need to locate the template. I added a Pioneer Amp. later which made a HUGE difference. The signal goes into the Amp. VIA the stock Lexus subwoofer speaker wire. At first, the sub did NOT perform well at all and I was disappointed. However, after a few weeks it suddenyl began performing rather admirably. I think it was that the subwoofer had to be broken in. I am satisfied with the performance now. It gives off a fairly impressive amount of bass and boom, with no distortion at faily loud levels. If you go over 45 with the volume, however, it bottoms out the sub as it has no more to give due to its size. Good enough for me however. Let me know if you would like the template!

LS500Fan

Thanks for the information you gave in this thread. I have a newer ES and I was considering my first choice to add more bass of replacing just the subwoofer. It appears I will need to plan on replacing the sub and adding an amp, my second choice. Thanks!