Well, this weekend is the big install in the FJ, but I have a few questions first. Some of these may seem stupid (at least to me), but I would rather be safe than sorry.
First, I have never used a line driver before so I have a few questions. On the SLD44 how do I measure the voltage output on the RCA's? I'm using this to keep the factory headunit, and the amp I'm using is a Xenon 200.4. Next, what voltage would you guys recommend sending to the x200.4. Next, does anyone know what wire I should use to wire up the remote turn on for the SLD44 and the amp and do you guys think there is enough voltage to split it to the SLD44 and the amp? This vehicle does not have a power antenna so I'm not even sure the wire is there. Finally, does anyone know where to get a wiring diagram for a stereo in a 2007 Toyota FJ Cruiser? I'm sure this will come in handy!
Thanks guys, these are the first questions that come to mind, I'm sure there will be more.
Play a 60Hz test tone and measure AC volts with your multimeter between the RCA center pole and shield. Apparently the Xenon can accept 10-12 volts without issue, so feel free to go nice and high if you can. Ideally you would have an oscilloscope, and then adjust this to just below the point of clipping, but not many of us have one.
Alternatively you can hook up the multimeter at your Xenon amp outputs, turn the gains all the way down, and adjust the SLD voltage until you get your desired power out of the amplifier. So if you had a 200.4 you would adjust the gains on each channel of the SLD until you got 200 watts... E-Z!
And a another quick tip, go as high as you can on the SLD level and have the amp gains low. All this does is let your amp see the most powerful, highest signal/noise ratio possible. I personally find the term "gain" to be quite deceiving of the purpose of this knob, I much prefer "sensitivity".
Setting up this way doesn't mean your amp isn't working as hard at the same volumes with SLD lower and amp gains higher or make your amp run cooler at same actual output levels as some may suggest though.
Doing it this way also sets a safe "ceiling" on the signal you can send to your amp, if done right. Tom did this for my system and it sounds just great and I know my amps are well within normal operating ranges at whatever my H/U output level it at so my amps won't burn up or clip.
Well, the preamp stage won't be working as hard at least. In fact, you could even bypass the preamp like they did in the ZPA series, but that would require a wizard like Cecil or Eric to do
I don't think the outputs of the amp will get any less hot or stressed with a hotter preamp signal... if it's got a 2 volt signal coming in, and has to boost that signal with the preamp to 8 volts, or if you have an 8 volt signal and don't boost it at all with the preamp... either way the output stage is seeing the same input voltage, and it should produce the same output voltage as well.
The main cause of amp stress and overheating is clipping! Set those gains properly folks
I do agree that sensitivity is probably a better name, but no matter what you call it, everyone will continue to think "VOLUME".
I love coming to someone's professionally installed car stereo to see the gains and bass boost turned all the way up. I ask them if the store did that... of course not... they turned them both up to full blast because it wasn't loud enough. So now with the volume at 3 on the dial, they are seriously clipping... you can't hear the stock front stage powered off the stock deck over the bass whatsoever. Of course they then crank the volume to 50, and the subwoofers are essentially playing one note square waves. Awesome!
Perhaps this would be less of an issue if people bothered educating their customers, then again, that would be a huge hassle, and most people don't want to be educated in the first place!
Of course, I have seen cars with bass boost and gain cranked straight from the install bay as well... Typically Best Buy + Future Shop.
stipud wrote:Perhaps this would be less of an issue if people bothered educating their customers, then again, that would be a huge hassle, and most people don't want to be educated in the first place!
plus you can sell them more gear in a few months!
my ex-girlfriend said "its car audio or me"
i've had tougher choices at a soda machine...
Is 18 gauge wire good enough for 400 watts over a 5' span? If not I have to go buy some 12 gauge. Normally I use 12 gauge, but it appears that I am out at the moment.
Electronically it would be plenty, but 16ga would be much better. If anything the larger wire is nicer as it will handle the loss of a few conductors due to flexing.
Even though I won't get to it today any suggestions on x-over points and how to set them on the x200.4? I have never used amp x-overs before. The sub is an Exile slimline XT12" in about a .9 cuft box, specs here. The comps up front are Exile slimline XP65's, specs here.
Set them initially to a common position, say 80Hz for example.
Adjust them by ear accordingly when tuning the system.
There is no perfect setting for a vehicle with all the variables such as speaker placement, power, box design, etc.
The goal is not notice where your woofers are located, in other words the lowest possible crossover frequency for them, such that you do not have a hole in your frequency response.
Eric D wrote:Set them initially to a common position, say 80Hz for example.
Adjust them by ear accordingly when tuning the system.
There is no perfect setting for a vehicle with all the variables such as speaker placement, power, box design, etc.
The goal is not notice where your woofers are located, in other words the lowest possible crossover frequency for them, such that you do not have a hole in your frequency response.
like he said but I would try to shoot for 63hz w/ 24 db slope.
Can one send others to war if hes not willing to go himself?
PROBLEMS!!!!! I have the line driver all wired up, and it has power, but it says that it is not getting a signal. I'm using the high inputs because I'm keeping the stock headunit, and it seems to be delivering about .01 volts to the SLD44, yes it reads .01 volts. Also, the button is switched correctly for the high inputs. What am I doing wrong?
What wires did you splice into for the high-level signal? Is there a factory amplifier in an FJ Cruiser? And just to be certain, both of the switches on the SLD44 are in the "UP" position, correct?
dedlyjedly wrote:What wires did you splice into for the high-level signal? Is there a factory amplifier in an FJ Cruiser? And just to be certain, both of the switches on the SLD44 are in the "UP" position, correct?
I spliced into the front speakers, and yes I'm positive. There is a factory amp, but it was in the factory subwoofer box that we sold. And yep, both switches are in the up or out position. I'm kinda stumped here.
So it sounds like the amp you sold must have only powered the factory sub...the factory full range speakers still play fine, right? Sometimes if you grab the signal before a factory amp it is actually low-level and not enough to run into a line output converter. Did you splice in right behind the factory deck? You could test to make sure there isn't another amp somewhere (powering the remaining factory speakers) by using a test speaker and hooking it up where you made the splice for the sld44. If those wires drive the speaker to adequate level then it should be high-level. You could also confirm that the sld44 is functioning properly by testing it in your Saturn (or any deck if you have a test bench). I assume you're using the signal led on the sld44 to determine that signal input is the issue.
dedlyjedly wrote:So it sounds like the amp you sold must have only powered the factory sub...the factory full range speakers still play fine, right? Sometimes if you grab the signal before a factory amp it is actually low-level and not enough to run into a line output converter. Did you splice in right behind the factory deck? You could test to make sure there isn't another amp somewhere (powering the remaining factory speakers) by using a test speaker and hooking it up where you made the splice for the sld44. If those wires drive the speaker to adequate level then it should be high-level. You could also confirm that the sld44 is functioning properly by testing it in your Saturn (or any deck if you have a test bench). I assume you're using the signal led on the sld44 to determine that signal input is the issue.
That and a DMM. I really don't think there is another amp downstream. Here is the electrical schematic for the FJ (audio on page 236). If I read it right there is nothing in between the headunit and the speakers. Maybe I should tap into the subwoffer wires, since there is an amp used there they should be high level??
Does the SLD44 have transformer coupled inputs? If so, are there 4 of them all independent of each other?
I have never seen a SLD44, but if it does not have transformer coupled inputs, there is a chance it is common grounded between all of its inputs. If this is the case and you have the polarity backwards on just one of your factory wires to the SLD44, you may be overloading its ground circuit, or the deck may be forced into a protection mode where it will not output anything.
You could try just connecting one channel from your factory system to an input on the SLD44 and then seeing what you get. Maybe you have done that already.
SUCCESS!!! Apparently the signal out dials were turned all the way down from the factory. After thinking about it all night long I decided to test the speaker leads with a speaker. After I verified that the signal out from the deck was good it was down to the SLD44. After more pondering I decided to try the signal out dials and walla, I had a signal out!
Thanks for all the help so far guys! I'm sure there will be more questions to come.
Good News: Everything is in and everything works!! It sure feels good after working on a project for 3 days and when you turn the key on everything kicks on like it should.
Bad News: There is a hiss. The amp is grounded with both hookups and I sanded the chassis down to bare metal. The grounding point are within 2 inches of each other. I did upgrade both of the grounds under the hood, batt to chassis and chassis to engine block. Both were sanded down to bare metal and reattached. Also, I did sand down the ground for the SLD44 just for good measure. Everything is attached to the chassis. Any ideas??
