Xenon 1200.1 low output.

[GreenXa]

I am having some problems with my old faithful xenon 1200.1 and was hoping for some help.

When wired up my sub output is very low, this was not the case in my last install with the same equipment, the source unit is the only difference now.
With gains on full the sub output is mininal with my front stage easily able to over power it, the sub also has some sort of feedback noise when no inputs are connected and gains are set back correctly. I have tried connecting the sub over different channels/configurations.

During the install I stupidly wired my front stage amp off the secondary power terminals of the xenon for a short period, the xenon wasn't connected to any inputs or outputs when this was happening but I am concerned this has caused some damage. Does any1 know if/how this could have damaged the amp?

System comprises of a ford 07' (australian) OE unit modified for RCA outputs, feeding the PG running an Alpine Type X 12"

Thanks for any help.

[kg1961]

have you tried a different sub or amp to see where the problem may lie. I know the x amps love a line driver 8 volts

[vwdude]

So your head unit is an oe unit modified to have RCA outputs...how was this done? What's the signal voltage coming out? You might need a line driver if the voltage is too low.

[Weaklink]

Did you change the box? If so you may have accidentally wired a voice coil out of phase.

[GreenXa]

Source unit was sent back to manufacturer for RCA mod. Output voltage is low approx 1V but my 4 channel POS sony is running off it fine. I understand a higher input voltage would be better but I don't require the xenon to run at its full potential in this install.
Sub wiring has not been touched since last removal, but has been checked over anyway.
I haven't tried another input signal as my other amp is working ok.
I am concerned the amp is damaged as it is producing noise with no input signal plugged in and the output signal is extremely low, ie at full gains and volume barely moving the sub at all.

Thanks for any suggestions so far.

[dvnt88]

Pull the cover off the Xenon and do a visual inspection for anything out of the norm ...and if you can smell a very pungent burnt plastic kind of smell , you may have blown something in one of the many operating circuits in the amp , but do a visual and smell inspection 1st to be sure.

[Bfowler]

1v is super low for that amp. xenons need a pretty hot input to reach full potential. i used to run my xenons at about 14v. if you can...throw a line driver in front of it. im very confident it will fix your problems.

i always use the car analogy. you can run a civic fine with regular gas (the sony) but you can't expect a high high output motor (xenon) to run well without premium fuel

[GreenXa]

1v is super low for that amp. xenons need a pretty hot input to reach full potential. i used to run my xenons at about 14v. if you can...throw a line driver in front of it. im very confident it will fix your problems.

i always use the car analogy. you can run a civic fine with regular gas (the sony) but you can't expect a high high output motor (xenon) to run well without premium fuel

So are you saying you think there maybe nothing wrong with the amp? What about the noise produced with no signal input plugged in?

The manual states to set the gain knob at your approx input voltage, and its settings go as low as 0.2V so I thought it would be fine.

I hope you are correct, ill plug my ipod in directly to give it a quick test.

[kg1961]

that is what they said but real world has shown it need 4volts plus so 4 time more than you are using

[GreenXa]

Ok plugged in my ipod dock to RCA cable directly to the Xenon, fed in some gain and it was firing the sub very nicely - looks as tho I need to boost that line voltage, im assuming the ipod would be feeding 3V at most so a signal of 4V upwards should work nicely.
The small amount of noise is still present but I will live with that for a while and see if it will actually be audible once the system is completed.
Im guessing a PG line driver would be the way to go? It's either that or I go to something like a Audison Bit unit.

[GreenXa]

Ok looking for further advise.
I used an Audiocontrol EQS unit as a line driver and I still have next to no output from the PG. Again tested over all channels etc and it is the same. If I plug my ipod directly to the PG it will run the woofer well still...
Any thoughts?

[vwdude]

How many volts does audiocontrol unit put out?

What kind of head unit/ vehicle are talking about?

[GreenXa]

Audiocontrol unit states max peak output of 14v.

Ford fairmont 2007.

[Weaklink]

Unplug one rca at the amp. They may have gotten one out of phase in the modding

[GreenXa]

Ive tried switching rca inputs, and channels around, using only 1 rca lead, adding a Y adapter, removed working RCA from running front stage amp then plugging into PG etc. But still no good, its as if the line driver has made no difference, but that is working on my other amp.

[Weaklink]

Ok got a long shot. Could they have gotten the pis and neg switch on the rca outs? And the pg uses a chassis rca shield on the amp and the sony is isolated? So when the rcas are plugged into the pg the pos is shorting to ground?

[GreenXa]

I borrowed an old Alpine deck and temp wired that up to the amp. With amp gains full and headdeck volume on full it would run the sub hard.
I have the sub installed, Audiocontrol pre-amp input and output gains at full, added some boost via equalizer tuning, xenon gain full and lpl44 turned up bout 3/4 and it runs the sub hard enough to keep up with front stage, but it sounds rubbish.
I figure something must be wrong with the amp as with all that gain and input voltage I would think it should be trying to turn that 12" inside out.

[knightrider358]

There could be something wrong w the amp, if uve tried swaping diff units in and have those volt level controls up and ur ac level up, its something w the amp, also it doesnt soumd like you swaped the amp, if u habent try that and see what happens, the signal coming out of ths ac unit should be min 8v rms being set right, try swapping the amp

[vwdude]

Are you able to open the amp up and take some detailed pictures to post? There might not be anything obvious that one of us might discover. There very well could be a cooked bank or resistors or a bad output transistor.

[GreenXa]

Next step will be removal and inspection of amp.

[Weaklink]

Was the audio control hooked to the alpine or the other deck in the last test?

[GreenXa]

No didn't use AudioControl with Alpine deck.

[GreenXa]

Ok bit of an update for peoples thoughts. At this stage I am trying everything before removing the amp and sending away as it is not a cheap or quick process in Australia apparently.
I measured the input signal to the 1200.1 using a 60hz test tone - went up to 10volts on one channel only. So i installed a splitter on this channel to feed both inputs on PG and this gave me a noticable increase in output.
I still feed there maybe something wrong with amp tho, as I would have thought with this much input voltage and gains set at maximum it would be hitting this sub extremely hard and I would notice it going into clip quite early.
Is it possible for something to fail internally which would just effect output without the amp stopping operation completely I suppose it what I'm asking now?
This sub and amp combo running in my old setup (4V max input) was making a lot more volume.

[trickyricky]

This is how I would test it. Set all the gains to 8v (or turned "down" all the way)...same bass boost controls on the amp. Set it to bypass the amp's crossovers (very important). You can test it on a bench w/power supply (15amp power supply should be enought to power it up and test it without loads) or have it hooked to your vehicles power. Fuse size is not very important so even a 15amp fuse should be plenty.


-Line driver sending a 60hz sine wave @8v to the Xenon amp.
-Set the DMM probes inside the speaker output terminals and set it to AC. Now adjust the gains in order to get 69v...remember this is a mono amp so if it has dual speaker output terminals they are PARALLEL and both should read exactly the same.

If for some reason the amplifier is not able to put out 69v without a load (by load I mean subwoofer) then the amplifier may have problems....assuming you did feed both RCA inputs with the same voltage signal (RCA y-splitter)


If you already tried this then let me know what you got as far as output voltage... Its also a smart idea to monitor the amperage the amplifier may be drawing...for this you need another DMM or Amperage Clamp Meter (make sure it reads DC current). While doing this test the amperage shouldn't rise above 5amps. Monitor the input voltage as well ON the amplifier's power terminal not your battery.


You mentioned the AC voltage went up to 10v "ON ONE CH"....but the 1200.1 is MONO so its only one channel. If this is the case then the terminal set that didn't produce voltage may be damaged (cold solder, crack solder joints, open trace).

[GreenXa]

Thank you for that info. I will run that test and get back to you.
BTW when I said 10v AC "on one channel" i meant on the RCA inputs to the amp - not it's output.