Hi gang,

I'm having a weird problem with my car system and maybe someone can help me
ID the cause before I just go and replace everything needlessly. When I turn
on the system, it *sometimes* takes as long as 20 or 30 seconds to start
playing through the speakers. *sometimes* it thumps when you turn it on,
sometimes not. Sometimes it will rumble very loudly and then start playing.
Even after it starts, I cant turn it up at all or it will cut out on the
loudest part of the program material, even if its just talk radio.

I tend to keep car audio stuff for a long time, so maybe it's the age of
some of my stuff catching up with it. Here's what's in the car, a 2002
Toyota eCHO. A lot of the same stuff has travelled with me through a few
vehicles, including a Kenwood 10 CD changer thats at least 10 years old.

Kenwood head unit, one set of preouts
Kenwood 5 band EQ, three sets of preouts, front, rear and sub
Kenwood 10 CD changer.

I just replaced all this stuff with a new Kenwood HU and the problem didnt
go away, so it isnt this stuff.

the front speakers are kenwood separates in the door and dash. These are
only about a year old.

rear deck is a pair of Kenwood 7x10 triaxials. They still sound great even
though they are ancient.

subwoofer is a single boston Acoustics 12" in a large ported custom
enclosure.

The front and rear speakers are pushed by a PPI Sedona series 460 amp.
(4x60w RMS) This amp is pretty old and I think it may be crapping out on
me. I hope not, since it's been a great performer for years and years. I
used to bridge two channels and push the sub (200w) and power the rears with
the other two 60w channels. The fronts were head unit powered for a long
time (useless) then I bought a crappy 2x40w pioneer amp to push them
(slightly less useless but still crap). Finally I bought a US Acoustics
USB2100 to push the sub (bridged to 300W) and started using the PPI to power
the front separates. I used the Xover output of the PPI to send the LP
signal to the US Acoustics sub amp. It sounded incredible.

I used this system for a month or so before this stupid problem popped up.
Here's a couple things that may or may not be relevant:

The problem started happening during a long string of very hot days..over 90
degrees. I drive in my car for a living, so the system is used about 8
hours a day, sometimes turned off and on only 5 minutes apart. I thought it
might be heat related so I dropped the back seat backs to let AC air in the
trunk (amps are mounted on the sub box facing the back of the rear seats
with about 6-8" of airspace).

I should also mention that I know the power feed is inadequate. Its only an
8ga wire feeding 540 watts of amp. I am in the middle of putting in a 4ga
wire split between the two. Both amps are grounded (8ga for each) in the
trunk to a big fat screw driven straight into the metal of the body in the
trunk structure.

the questions: could this inadequate power supply have cooked the old PPI?
Is this weird fading in and rumbling/thumping a symptom of an amp that's
going south? I am upgrading and redoing all the wiring because i think I
may have to replace the amp. I am happy with the US Acoustics stuff for the
$$$ and will probably go with a USB4065 to match the USB2100 since I will be
losing the Xovers in the PPI.

ANy info is welcome. Thanks for your time and knowledge.

~daxe
http://www.snakefoot.com

he front and rear speakers are pushed by a PPI Sedona series 460 amp.
(4x60w RMS) This amp is pretty old and I think it may be crapping out on
me. I hope not, since it's been a great performer for years and years. I
used to bridge two channels and push the sub (200w) and power the rears with
the other two 60w channels. The fronts were head unit powered for a long
time (useless) then I bought a crappy 2x40w pioneer amp to push them
(slightly less useless but still crap). Finally I bought a US Acoustics
USB2100 to push the sub (bridged to 300W) and started using the PPI to power
the front separates. I used the Xover output of the PPI to send the LP
signal to the US Acoustics sub amp. It sounded incredible.

I used this system for a month or so before this stupid problem popped up.
Here's a couple things that may or may not be relevant:

Ok question for you. Are all you switched things all running off the same
remote without a relay? That could be part if not all of the problem.

The problem started happening during a long string of very hot days..over 90
degrees. I drive in my car for a living, so the system is used about 8
hours a day, sometimes turned off and on only 5 minutes apart. I thought it
might be heat related so I dropped the back seat backs to let AC air in the
trunk (amps are mounted on the sub box facing the back of the rear seats
with about 6-8" of airspace).

I should also mention that I know the power feed is inadequate. Its only an
8ga wire feeding 540 watts of amp.

8 gauge is enough for that. Keep in mind that its music your listening too,
very rare do you get the peaks and probably not more than what 8 can handle.
But going to 4 wont hurt it at all.

I am in the middle of putting in a 4ga
wire split between the two. Both amps are grounded (8ga for each) in the
trunk to a big fat screw driven straight into the metal of the body in the
trunk structure.

I am not sure I like the big fat screw. Screws have a tendency to work loose
over time, I prefer a big fat bolt.


the questions: could this inadequate power supply have cooked the old PPI?

Not likely.

Is this weird fading in and rumbling/thumping a symptom of an amp that's
going south?

Could very well be, but there are other things to check out

I am upgrading and redoing all the wiring because i think I
may have to replace the amp. I am happy with the US Acoustics stuff for the
$$$ and will probably go with a USB4065 to match the USB2100 since I will be
losing the Xovers in the PPI.

USacoustics are good performers for the money. Sounds like youve got a good
plan.

ANy info is welcome. Thanks for your time and knowledge.

~daxe
http://www.snakefoot.com

Well I would definantly fix your apparant remote problem. Once that is done see
if you cannot borrow an amp from someone and see if the problem is still there.
Report back

Les

"Soundfreak03" wrote

Ok question for you. Are all you switched things all running off the same
remote without a relay? That could be part if not all of the problem.

I am going to answer yes only because I'm not completely sure what you are
asking and if there's a way to do it wrong then I probably did it! )

The 12V feed from the battery goes into the trunk and straight to the PPI
amp. I ran a jumper from the PPI over to the USA amp for power. To turn
them on, I am using the turnon feed from the head unit, which also goes back
to the PPI, then is jumpered over to the USA. Maybe worth noting that the
USA has a "fade in" feature but the PPI does not, at least not as gradual.
The PPI takes a second to juice up (or used to anyways) but then its at full
volume. Even after this weird problem happens, the whole setup seems to
work OK after a running a while. I thought maybe there just wasnt enough
output in my elecrical sysem (Toyota Echo) to power everything up after
using the battery juice to start the car, but it's not consistent with that.
To experiement, I have left the sound system off for half an hour after
starting the car and then tried to crank it up with the same results. I
also took the USA amp out of the loop completey and it did the same thing.
Remember..this whole setup worked perfectly for at least 6 or 7 years..

Are you saying I should have a relay set up to trip via the remote turn on?
what is the relay going to control?

8 gauge is enough for that. Keep in mind that its music your listening
too,
very rare do you get the peaks and probably not more than what 8 can
handle.
But going to 4 wont hurt it at all.

The USA amp declares that it requires 8ga just by itself, but I will take
your word for it. The 4 ga is already run from the engine compartment to the
trunk, so it will be hooked up ina bout an hour from now if it doesnt rain.

I am not sure I like the big fat screw. Screws have a tendency to work
loose
over time, I prefer a big fat bolt.

easy enough to change. I will make sure the ground is solid at any rate.

Is this weird fading in and rumbling/thumping a symptom of an amp that's
going south?

Could very well be, but there are other things to check out

I tried turning the amp on without any input signal and nothing else hooked
up and it still made the thump/rumble, so I would say it's definitely that
component, just need to know why.

USacoustics are good performers for the money. Sounds like youve got a
good
plan.

thanks and thank you for your input.

Well I would definantly fix your apparant remote problem. Once that is
done see
if you cannot borrow an amp from someone and see if the problem is still
there.
Report back

do you have an URL for an online schematic or reference for this remote
setup you mention?

thank you again,

~daxe