2 12" subs in the BRZ!
 

Thought I'd brag about the subwoofer setup I just finished! :party0030:

A few things to note about audio:

-2 12" subs are more than enough to complement the stock system.

-When idling, my RPMs drop by about 500 when the subs play a note. Is this just caused by the engine's lack of torque (which is most likely what it is, I just want to be sure) or do I have a more serious problem?

-Never use bluetooth to listen to music on this stereo. Way too much quality loss, it sounds awful.

-For the most part, I'm satisfied with BRZ's soundsystem. I'll probably drop in some new tweeters at some point, but other than that it's good enough for me.

edit: the picture isn't showing up for some reason... just use this link.

https://drive.google.com/open?id=0B5...S28&authuser=0

https://lh5.googleusercontent.com/Ii...6jM=w1332-h490

I think the RPM loss you're talking about could be due to the alternator not having enough strength to keep a constant voltage.

You might need a more powerful alternator, but I'm no expert.

As an aside I really expected to see this, as given to us by @racecaresuaceb in the "Junk in the Trunk" thread...


http://www.ft86club.com/forums/showthread.php?t=7130


http://www.dudelol.com/img/two-12-subs-in-my-trunk.jpeg

Your subs are sitting on the backseat? Well, that'll certainly work.

Go get yourself a deep cycle battery.

Perhaps a capacitor is needed? Sounds like the voltage is dropping when the subs hit. This could be a bad thing... Do the headlights dim?

Bluetooth audio doesn't sound significantly different than CD to me. USB to iphone sounds the best, but acoustically I'd like to see some data to back this up. Bluetooth is very well researched and implemented as an xfer medium as far as wireless goes.

I do music production and mastering as an aside, my ears aren't legendary by any means but I make it a point to have high fidelity, beautiful sounds in my life every day (Yamaha HS80s, NI, Event 8 inches, fully sound-staged and trapped master room.. tons of DSP, tube processing racks, etc.. I love music. :) )

That being said, the 2013 paper cone system is totally junk in both BRZ and FRS models.. updated pio headsets are a huge step up. Bluetooth music might sound terrible to you because of an improperly set up sound stage combined with a huge disparity in your low-end (read: you're overpowering the already fatiguing stock setup with your dual 12's)

1. What's your drivers and amp specs?

2. Does the alternator kick in for every large electrical load/"sub notes"- or just intermittently?

I'm a bit of an audiophile, just throwing that out there beforehand. Maybe not to the extend of Koa, as I have not done music mastering myself.

Bluetooth audio quality has a gotten a lot better in the past couple years, but still suffers compared to a CD (if mastered correctly and not just with all volumes LOUD as a lot of record labels record nowadays) or a usb device loaded with high-quality audio files (at bare-minimum, a higher-bit-rate mp3, or preferably, a FLAC file or similar).

Recent upgrades in Bluetooth hardware and software protocols have made transfer speeds faster than ever, but at the end of the day, Bluetooth is always compressing the audio file to an extent before streaming it to the device it is connected to. Certain music genres are more noticeably different than others. To me, it just always sounds like an old 128kbps mp3 from early online music download days...

Agreed with everyone else concerning the car problems when the bass is hitting. A capacitor set-up sounds like it might help. You shouldn't need a new battery/alternator for just two 12's, unless you're running some crazy amplifier on this thing...

Guys please don't recommend a cap.. those are very inefficient ways to tackle the problem.


OP you need to invest in a Stinger cell battery or equivalent mods if you're having draw issues. Alternatively, one can invest in a deep cycle battery but I've never had great success running the Optima blues- their QC is terrible. Perhaps it has changed over the years.. There's a reason why serious enthusiast/comp car audio builds are using seperate cell batteries to help with draw.

How are your grounds? Where did you ground the amp to? Those play in huge to proper audio circuitry and if the ground is shitty, your current management will be shitty.

I will agree that the compression from current gen Bluetooth 3.0 and 4.0 aren't better than lossless or even full 320kbps 44 tracks but it does help to distinguish the difference between early Bluetooth technology (BT 1.0-2.X), and current tech.

Iphone 5 I believe was the first to offer Bluetooth 4. I strongly suggest A-Bing the SAME track on USB, cd, and BT 4.0. I stake that a vast majority couldn't tell the difference.. that's a test that requires a bit of a large sample, but would be easily replicated and procedural.. able to be re-tested.. all the requirements to a good empirical trial :)

Get on www.DIYsoundgroup.com and look into the Fusion 10, 12, or 15. Any one of those will just astonish you with its effortless clarity and detail, especially at reference levels.


Then get on AVSforum's DIY forum and look for lilmike's lilwrecker, microwrecker, or cinema F-20 for the low end. A proper horn-loaded subwoofer is an amazing thing. Again, effortless authority, clarity, and power. The lilwrecker has a low end corner of 17 Hz at 115 dB, with a plain old Alpine type S 15" ($115) at 500 watts. If you need moar lower, look into a gjallarhorn, g-horn v2, or othorn. Now you're looking at a low corner of 10-12 Hz at 100+ dB. Those use much much more expensive drivers and much more power though.


For stereo music, I would do Fusion 12's or 15's, a lilwrecker in the front, and a cinema T-6 horn elsewhere in the room to minimize room modes. If I was doing a theater, I'd do three Fusion 12's or 15's across the front, and four Volt-8 or Volt-10 coaxials (wider dispersion, better off-axis response) for my surrounds. Two lilwreckers in the front, and a microwrecker in the rear.


Perfect clarity at reference level volume. It's a glorious thing.

While those are great for home theatre use... I'm talking about music production and mastering, which requires a base of flat sonic monitors and reference points downstream to sample the lossy bytes. In my home studio, I employ the Event active nearfield 2030 3-ways as my mains

http://www.soundonsound.com/sos/apr1...event-2030.htm

Then use Yamaha HS80m's for add'tl reference

http://usa.yamaha.com/products/music..._series/hs80m/

All in a fully bass trapped and sound attenuated room :)

Having done multiple high power audio installs over the years, I would not add 2 subs to this car without adding a new battery/alternator. The electrical output of both battery and alternator are not sufficient to drive two subs without significant power loss. Either tie in a second battery or install a deep load one.

A mild dip or headlight dim is manageable, but losing 500 rpm is some serious leeching that you need to sort out.

He's using a boss amp with what looks like one 30amp fuse. I find it hard to believe his 500rpm drop is due to this amplifier drawing too much current from the electrical system.

I'm probably drawing at least 100A with my setup and my RPMs are rock solid. Granted, yes, I probably would benefit greatly from a hi-amp alternator.

I'm not sure how you get 10-12 Hz response out of a horn loudspeaker. The low frequency rolloff of a horn is determined entirely by the size of the mouth; the bigger the better. But you would need a horn with something like a 32 foot mouth diameter to achieve that sort of low frequency response. Perhaps with a lot of equalization and a MOTHER of a big amp, you could do it, but then you lose the entire advantage of a horn, i.e., low power requirement.

If you plan to use a lot of power, then just use a regular cone driver and equalize the bass until the curve is correct. Cheaper and easier.

For a full wavelength horn, yes. A quarter wavelength horn doesn't need to be quite so big.

A gjallarhorn uses a single 18" LMS-Ultra 5400 driver, which is a beast. Here are some measurements on it: http://www.data-bass.com/data?page=system&id=45&mset=42.

And a couple build threads with their own measurements:
http://www.avsforum.com/forum/155-di...orn-build.html
http://www.avsforum.com/forum/155-di...llarhorns.html

The othorn uses either a B&C 21" 21sw152-4 or an 18" TC Sounds 5100. It won't reach as low as a g-horn, but it takes over at 25 Hz and just walks away with it.

Data-bass: http://www.data-bass.com/data?page=s...id=95&mset=102

Build thread: http://www.avsforum.com/forum/155-di...orn-build.html

The data-bass measurements are ground plane measurements with no corner loading and only a high pass filter, so it's about as clean and unaltered as you can get.