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jmcl · 06-29-2012, 02:04 PM

I'm looking for a schematic for the HAES M490 amplifier. This amp was/is used on many 986s.

In it's stock configuration this amp drives the dash speakers and the door speakers. It seems that the stereo channel used to drive the door speakers has a low pass filter, so only "lows" are delivered to the door speakers.

I want to keep the stock amp but I would like it to drive "normal" door speakers (yes, I will replace the stock ones).

Since I have replaced my head unit with a Pionner AVIC I can now drive an external subwoofer, so I really don't need the silly woofers on the doors. IMHO a much better use for these speakers would be using regular ones instead of tiny woofers.

Here's an internal pic of the amp that I'm working on.
Any information on a schematic or any information that can help me remove the low pass filter from this amp is welcome.
Thanks!

06-29-2012, 02:04 PM	#1
jmcl Registered User Join Date: May 2010 Location: Lisbon Posts: 23	986 HAES Amplifier I'm looking for a schematic for the HAES M490 amplifier. This amp was/is used on many 986s. In it's stock configuration this amp drives the dash speakers and the door speakers. It seems that the stereo channel used to drive the door speakers has a low pass filter, so only "lows" are delivered to the door speakers. I want to keep the stock amp but I would like it to drive "normal" door speakers (yes, I will replace the stock ones). Since I have replaced my head unit with a Pionner AVIC I can now drive an external subwoofer, so I really don't need the silly woofers on the doors. IMHO a much better use for these speakers would be using regular ones instead of tiny woofers. Here's an internal pic of the amp that I'm working on. Any information on a schematic or any information that can help me remove the low pass filter from this amp is welcome. Thanks!