Hi everyone,

I have found numerous threads on this topic through searching the forums, but I just wanted added clarification:

Caution: I know nothing about car audio

I have a 1998 GS400 with the stock pioneer unit. I bought the Kenwood Excelon DPX592BT head unit to replace the factory unit. I've learned that the factory amp will not work, thus stock sub will not work after replacing the HU, so I also bought an amp to power the stock subwoofer (I may upgrade later). The amp is Rockford Fosgate R500X1D.

I just wanted a better overall sound with modern technology, not looking for teeth chattering bass or anything (not for now, anyway ). It would also be nice to see what radio station and such that I'm on since the screen on the factory head unit has died, which seems to be common.

My question: is it possible to use the new amp with the stock sub? I'm not sure what the stock sub is rated at RMS wise, but it shouldn't be overpowered by the sub or anything?

Thanks in advance!

 

You'll certainly blow the shat out of the stock woofer with that amp... Just use common sense, if it sounds like the woofer is being overpowered... turn the gain down on the amp. My suggestion is to take your time tweaking the amp for that woofer. make sure the gain is at a decent level to not overdo the sub, make sure the frequencies are set in a place that the sub likes. Personally, I'd keep anything above like 80hz away from the sub, the door speakers do a very good job with those frequencies. But do replace that sub soon just for peace of mind.

Best way to find the right level for the gain on the sub amp for this configuration (and please do this in a parking lot away from people )... with the sub amp at its lowest level, turn the gain on the Kenwood to the loudest that you would ever use it at (dont go over 3/4 the total volume. if it maxes out at 100, dont pass 75. If it maxes at 40, dont go past 30 etc...) anyways, once you find that high level, slowly begin to turn the gain up on the amp until you hear the woofer popping or sounding weird. When you get to that level, turn the gain on the amp down a slight bit.

Doing it this way ensures you that you'll never turn the gain on the deck so high that the woofer will begin to pop or over-modulate. Now, once you've found this point, then at LOWER volumes on the deck, you can fidget with the EQ and add a little bass to the woofer to make it sound clean. With that amp, I dont see you turning the gain very high on the amp, that woofer is pretty soft with little control, that amp can instantly fry it if you let it...


Just my 2 cents in a very short version.

 

I actually have the manual for the OEM amp, it only pushes 40 watts to the factory 10" sub.
Your amp is definitely an overkill. A small 100watt amp is sufficient to power the OEM sub, but if you decided to keep that amp, follow Mr. Jokster's instructions.

I'll be doing some research on how to power on the factory amp. Since the system is AVC Lan based, it must detect a device for it to turn on. This is more on the electrical engineering side of tricking the amp.

Many of the guys here in Taiwan are interested since they want to upgrade the 2GS to a better headunit but don't want any crazy systems. Just want to keep some bass.

 

Thanks for the responses! I'll definitely follow that advice. I figured the amp would be an overkill, but I will likely upgrade more audio components, including the sub, in the future. So, I suppose its a way of "future proofing" for now.

Keep us posted on any research you find out. I think that would be of interest to many people here.

 

Under my understanding since being on this sight for 8 years, there is no way to trick this amp, however I have seen plenty of people replace their head unit Maybe it depends on if its a Pioneer or ML system. There is a thread in which a member opened the amp up and found absolutely no wire for turn on...

Honestly, I dont find it very hard to bypass the factory amp at all (if you dont mind doing some cutting or tapping at the amp location)

 

I did find this though...

 

IMO though, all you have to do (using the below picture) Remove the top plug, remove the bottom plug. Figure out which wires go to which speakers (on both plugs) use some of these on each wire of each plug:




and run a wire from one plug to the other. Or better yet, just cut them and butt connect directly.

 

The avc lan system has been very well studied by guys on the corolla forums. Generally you'll need 2 180 ohm/ 1 120 ohm and 2 zener diodes. If you search avc lan and 180 ohm I'm sure those links will pop up. That's the beginning of my research so far to trick the amp to turn on. There maybe more to it like sending a thread of code. But someone else on my.is confirmed that it works.