$40 Amp+LOC Install to OEM Radio

:
2008 Mazda5 GT
Keeping the trend of cheap is good... adding mo'powa to the wimpy OEM radio for $40. This was done Oct/Nov. Not sure if anyone here added an AMP to the OEM radio but I had some lessons learned that I hope will help others..

The amp is 6 years new (now discontinued, it was $30-35) ;) and the Install Bay LOC is the cheapest 4 channel passive LOC I can find @ $8 (now $5).
Nitro Bmw-x43 300 Watt 4 Channel Car Amplifier
Install Bay IBLOC04 4 Channel Adjustable Line Level Convertor 60 Watt Each

RpUDyQm.jpg

OJD1uh3.jpg


-Used Molex mini-fit jr connectors for speaker channels to quickly go back to OE
-Added pin OEM radio connection for 1J! I haz amp control BUT the results is not what I was expecting. The cheap Clarion radio was never intended to have true amp control where it powers the amp on/off with the radio. This is IMPOTANT to warm/delay amps for on/off control to prevent "pops". The 1J is a straight ACC +12v pass thru. It gets power with the key on ignition even if the radio is off - this really freaking sucks! Every now and then I get a pop when I turn the car off but it is minor and low volume; howver, if the radio is off and I turn it off, no pop. I can decrease the LOC gain to minimize the pop more but this also decrease the volume (what fun would that be). Perhaps a premium active LOC (Audio Control) can mitigate this. Its a minor annoyance for now.
-There is a 'decent' amount of space under the stock radio! Had to do some minor dremel cutting but this mini AMP fits underneath the radio and LOC fits behind it.
-Frist tried to piggy back off the radio harness +12V and ACC but blew the room fuse. Had to run dedicated power line (choose 16 AWG). I was hopping not have to do that but to be fair, the amp's manual does call for dedicated +12V supply. It was my fault for assuming all mini amps can just piggy back off the radio's power supply. At least it has good/clean power supply.
-There is a huge cavity where the info display panel is located (on top dash). I believe the OEM navigation (where offered) took some of this space. You can definitely (I think :p) fit a bigger amp in there but may run into heat issues b/c the top panel is exposed to the sun (heat) and heat from cabin vents go up to that spot. You may want to cut a small hole/slot and install a mini PC fan to vent.
-The issue is heat. I am pleasantly surprised this mini amp generate little to no heat (even with gain pretty high). What does cause heat behind the radio is the vent/duct work around it. The inner of the dashboard gets hot if you turn heat on. I don't think enough to melt things but still not desirable. I prewired for mini fan but didn't use it.
-Factory workers in China got the LOC wires codes all mixed up. Removed all pigtails and solder on shorter cables for direct wiring without needing intermediary wire.
-To make cubbie pocket, scan the base of the OEM radio and print out template. Pick a desired material and cut to size. Screw it on using cassette deck attachment points. You can get fancy and add wireless charging underneath or add a female USB charging port inside.


Results? Very good! aside from the occasional pop when turning car off but this is not the fault of the amp at this priced point, I blame the cheap Clarion radio for lack of proper amp control but some quality amps do have delay on/off to prevent pop. I like that it takes up zero interior space -this was my ultimate goal given the car is tight as it is. Don't let the size fool you, this little class A/B amp gives a nice bump to the OEM deck. Amazon reviewer tested it for + ~18watts RMS gain. For reference, stock radios typically output 9-11 watts RMS (safe to guestimate this cheap radio is on the bottom end). There's also mention of upgrading the capacitors inside for high drain. The board is pretty accessible easily modd-able. I can now actually distinguish that I have very sharp/high tweeters and the front stock speaker rattle (but not the rear, I think that space has too much air and poor dispersion). The gap with the OE radio is simply need for more power. The speaker (output) sound fine. Now, I want more EQ control. Too bad there's no place to mount one that is accessible. I'd like to use an old Pioneer digital EQ.
 
Last edited:
Yes, the Alpine and Clarion are two very good/better than options. My motivation was size. Believe it or not, these two mini are almost 2x size of the Nitro and they won't fit behind the OEM radio. However, I think they will fit in the upper dash panel. Also, there's a nice sized 'vertical' pocket behind the shifter, under the radio. These should fit there too HOEVER, you'd have to disassemble a lot of stuff to mount it. Adding the amp only makes me want more power... What I've want to do is rip put the rear speaker panel and replace that with a MDF boards with 8" shallow mount IB subs + 4" coaxial. But, no place for amp to drive it.


https://www.amazon.com/dp/ (commissions earned)
 
They're bigger because they use better guts and include the line output converter in the same chassis... but yeah. I used a PPI 5 channel class D amp under the passenger seat in the wife's 5. 4x60 to the corners, and 200w to the subwoofer. If you remove the storage tray in the rear under the floor, there's enough volume for about 1.2 cubic feet of subwoofer box. That's enough for a compact vented box for a 10, or even sealed for a pair of 10s. That's with keeping the spare too. I was going to fiberglass in a sub box under there with a cavity to lay the spare tire on top- but alas no more.
 

Latest posts

Back