bozzchem

Everything is in, the dash/console/passenger seat are sitting in the garage.

Double check all connections, put in the fuses and hit the power button..........

Front left comps not working, left subwoofer not working! (left rear speaker - working!)

I haven't had time to pull of the driver door to see what is going on there.

From troubleshooting the sub not working, it looks like the left channel of the amp has given up the ghost.

I've never had this happen before. Is it common to lose just one channel of an amp? I was initially scared it was my new HU or EQ. Since the rear left speaker works, I know it's not them. I swapped RCAs between the right/left of the subs and no matter what RCA went into the left channel....no sound. I tested the left sub from the right output and it's working fine.

Is there a way using a voltmeter to measure what's going into the amp and what's coming out of it to determine whether it's truly blown or not?

It's about 4 years old (USAcoustics 2200F) so I wouldn't have thought this would happen. Maybe in the process of removing it from my last car and storing it in my office, I knocked something loose.

Any suggestions?

Southbound

bozz,
Swap inputs to the amp to see if a signal is there. If the right side of the amp works REGARDLESS of which input is plugged into it... then you can assume that the amp should have an input signal, since BOTH inputs work when plugged into the good side of the amp. You have already checked your left side subwoofer wiring by swapping outputs. So you don't have a subwoofer wiring problem.

YES, it is just as common for ONE amplifier output channel to blow as it is for both. IN fact, in MOST cases it would only be one side or the other.
Are there any speaker line fuses with the new amp? I still don't quite understand what exactly feeds INTO your new amp inputs and what THE NEW AMP'S OUTPUTS FEED??? Sounds like you are still using a new HU and new EQ to feed the rear door speakers? IS that correct? Just the rear doors? What feeds the front door components? I think it sounds like the new amp feeds your front door speakers. and also your subwoofer? How is the subwoofer feed derived? Is there a second output from the new amp that is a low pass output made for subwoofers? IN ANY CASE.... I'D TAKE THE LEFT DOOR PANEL BACK OFF AND SET IT IN THE GARAGE TOO. ODDS ARE YOU HAVE A SHORT ON THAT CHANNEL WHICH IS SHUTTING DOWN THAT HALF OF THE AMP. If you're lucky, removing the short will bring the amp back to life without permanent damage. It's REAL easy to short out the wiring in the doors because of the lack of depth before the window. Also the window could have pulled the wires off of the speaker by rolling it up and down. IN that case the speaker may not be working simply because it's not hooked up, (but then the sub should still work) SOOOO, it may be laying in the bottom of the door frame and shorting out the entire amplifier channel... in which case, NO speaker on that channel would work, due to the fact that the amp has either blown or gone into self protect mode. Let's hope for the latter! It's happened SEVERAL times with the DX6 install, so it could be happening here as well. Check your wiring behind the left front door. My bet is that you'll find something shorting out somewhere. CHECK VERY CAREFULLY to see if a wire is just barely cutting into the door frame metal, etc. COMPLETELY disconnect the speaker leads and any splices so that you can visually see that no shorts are happening. If this causes the subwoofer to NOW start working. That would prove that you had a short somewhere on that channel. Put everything back together very carefully with PLENTY of insulation EVERYWHERE!

Good luck!
Southbound

bozzchem

Ahh, it's always nice to hear from one of the "masters" of this board

I'll try to put my problems into written words and hopefully you can point me in the proper direction for troubleshooting. I have nowhere near your ability for written descriptions, so I'll do the best I can.

1) Alpine CDA-9813 HU - NEW
2) AudioControl THREE.1 EQ- NEW

3) Image Dynamics Chameleon components for front doors - USED
4) Polk DX6 speakers for rear doors - NEW

5) Front/Rear amp - USAcoustics USX4065 (65Wx4) 4 channel amp - NEW
6) Sub amp - USAcoustics 2200F 2x300W @ 2ohm stereo - USED.

Upon power up to the HU, I immediately noticed that the front left comps weren't working and I immediately noticed that both subs weren't working.

I figured I'd tackle one obstacle at a time. To me, the easiest would be the subs. Since these were the same subs/amp taken from my previous car, I figured I knew them pretty well.

Once I realized that at least the rear Polk on the left side was getting sound, I ruled out the HU and EQ as having a bad left side.

So, on to the subs. The right side is hitting hard. My first thought was that the left sub had croaked. I used a set of speaker wires to series off my right sub and input it to the left sub which came to life and let me know that the sub is still good!

Hmmm, it must be something related to the amp then?. I unhooked the RCAs from the EQ and the amp. I left the right RCA from the EQ to the right input of the amp - woofer was rockin'. So, I swapped the RCAs and I used the left RCA from the EQ to the right side of the amp - still rockin. That ruled out the RCAs as the culprit. No matter what I input to the left side of the amp...the woofer is not responding.

I checked the speaker wires for continuity and all of them came up cleanly. Somehow my amp that was working perfectly when I took it out of my last car has stopped working on the left hand side. If the amp was 10 years old I could understand. It's only about 4 years old. Maybe I was too quick to tout the "bulletproofness" of the USAcoustics amps.

So, it looks like I'm going to go with the JBL digital class D amp as a replacement.

Any other troubleshooting tips will be greatly appreciated. I don't want to buy a new amp if I don't have to. I don't understand how it was working flawlessly in my previous car but I have somehow destroyed it moving it between the two......

I'm tired of my 2003 TL-S not having a passenger seat. I have to button this baby back up ASAP. If my amp is dead...it's dead. I'll give it the Viking funeral and kiss it goodbye. I would like to think that they don't die this easily though.

Oh well. Maybe I'm just too anal about all of this.

Thanks for all of the help you guys have provided to me in the past!!!!!

AcuraX2

It sounds like you have done about everthing you can to check out the amp. I think it is bad news. Sorry to hear about that. You finally get all your stuff in and your amp goes bad. Crap.

Iggy

Bozz,
Try this. connect the leads currently going to the right sub to the left sub. Then do the same at the amp side. This will determine if there is some kind of short in the left side speak wires between the amp and left sub. Just because you have good continuity in the left speaker wires doesn't rule out the possibily of a short.

Fingers crossed,
Iggy

bozzchem

I tried again today with a NEW set of wires going to the left sub. No dice. RIP........

I'm not totally brokenhearted. I did want to switch to a class D amp. The US had a tendency to overheat during the summer. It get's very damn hot in NC.

Thanks for all of your help guys.

bozzchem

OK, sub amp has been replaced.

I got a JBL BP1200.1 mono digital amp and a Stinger Pro 1 farad cap off ebay for $320 shipped. I could have gotten the amp new for ~$275 and the cap new for ~$100.

Since I've been somewhat of an anti-cap person, I figured I'd see if it's time for me to eat some crow. If the cap keeps my lights from flickering, I'll be hooked.

Either way, I'm going to have some SERIOUS power going to my IDQs soon! Now, do I present a 4 ohm, 2 ohm, or 1ohm load????

Hmmmmm.

Southbound

bozz,
One thing I hate is an uncontrolled nosedive. I think Iggy can relate!

There still seems to be one bit of confusion in my understanding of your setup.

You appear to have TWO aftermarket amps
ONE for BOTH the front and rear door speakers.

and ONE for the subwoofer. Is that correct?

If so, please explain your full system signal flow configuration.

What I am getting is:

1. You have a NEW HU.

2. This HU feeds LINE LEVEL SIGNALS to the NEW three.1 EQ.

3. The full bandwidth LINE LEVEL OUTPUTS of the NEW 3.1 EQ feeds the LINE LEVEL INPUTS to your NEW USAcoustics USX 4065 (four channel amp at 65watts per channel.

4. The four outputs of this amp then feeds ALL of your four door speakers.

5. You are using a LOW PASS SUB SIGNAL output from the NEW 3.1 EQ to feed you other aftermarket amp, the USAcoustics 2200F. (This assumes that the 3.1 EQ has both full bandwidth, AND low pass SUB outputs to feed both of these amps).

6. Then the outputs of your subamp, the USacoustics 2200F are being used to feed your actual dual subwoofers.

7. Do I have your configuration understood at this point???

IF the answer is YES, it seems to me that you have TWO problems.

1A. The fact that your left front door speaker does not work is an issue with the NEW four channel USAcoustics USX4065 FOUR CHANNEL AMP.

1B. The fact that your left channel subamp output is not working is a COMPLETELY differenct problem.

What are the chances of TWO amps having gone bad in your install? YES, if that is truly the case... you have stalled and gone into a spin. I suppose it could happen, but is there ANY POSSIBILITY that the two failures have SOMETHING in common? I'm not familiar with your NEW HU or the Three.1 EQ, but do they require some kind of configuration process to produce the proper output signals? Are there choices between low level and high level outputs? Are there choices between the bandpass and/or frequency response of the outputs? Are there muting controls, etc. If so, maybe one of those units is the common link to both problems? Maybe there is a mis-configuration set up on the head unit or EQ? This is wishful thinking... but you do have TWO separate problems involving TWO separate amps. That sounds rare to me, unless there is some kind of common link feeding both of them. That common link can only be the HU or EQ.

Again, take the door panel off of the left side and see if you can find out why the left front component speakers don't work. Also, READ all of the HU and EQ manual and make sure that there isn't some kind of setup procedure that could be causing this problem to both amps that follow. Then make sure that ALL channels of the amps work by swapping input and output cables around. You should be able to swap cables in a troubleshooting manner which would provide you with results to make deductive reasoning conclusions. After that, you would know what you have to do by knowing exactly which input or output is absent of a signal. Make sure there are NO HIDDEN fuses, etc. in any of the amps as well.

It sounds like you have done a lot of this already. But as Iggy stated, doing things with clip leads may or may not actually expose the culprit. Also if you indeed wired your subwoofers IN SERIES with test leads as a test... both speakers would still play with ONLY ONE channel of the amp feeding them. So that test may or may not have been valid. If you "OHM OUT" the speaker wires and they show continutity, that is a good thing. However, don't forget to ohm ACROSS the two speaker wires. It should provide you with the DC resistance of the speaker. Either 2ohm, 4ohm, or whatever. If it instead ohms out as a virtual dead short, then you may very well have a short on that speaker line per Iggy's thoughts. If you get a virtual short, disconnect the attached speaker and the short should completely open unless you indeed have a confirmed short. A 1ohm subwoofer may look a lot like a dead short when ohmed out by certain low quality volt/ohmeters. In fact, MAKE SURE THAT YOUR AMP CAN TRULY DRIVE THE IMPEDANCE OF THE SUBWOOFER SETTING. (I guess you have proven this with the right channel, but maybe you have things set different on the two channels?) An amp that can drive a 1 ohm speaker is truly impressive. While CLASS D amps run VERY efficiently and produce little heat... they are certainly nowhere as linear or as clean sounding as a common class AB amp. That's why they are typcially used only on subamps where the signal is huge (for rap and hip-hop,etc.) and SQ can be somewhat sacrificed. The ear is much more sensitive to the midrange and higher frequencies.

There could still be some good news for you, but it will take some more testing to be sure. Use some SHORT RCA cables that you can attach to an oscilloscope or AC voltmeter or a small speaker for testing purposes. (you may need to cut one end off and expose bare wires on that end to make things easier to perform testing WITHOUT SHORTING ANYTHING OUT DURING THE PROCESS!) Be sure you know which lines are what and DON'T CONNECT A SPEAKER TO A LINE LEVEL OUTPUT, or it could be damaged by the extremely low impedance... If you don't have an oscilloscope, you should be able to put a voltmeter across a signal line and in the AC mode, it should show some random readings corresponding with the music. It may be small fluctuations because the meter may have some damping circuitry to stabilize the readings. A voltmeter with an analog meter should also show movement with the music signal. The DC mode on the meter shouldn't show ANY voltage, unless the line is extremely high impedance. COMPARE THE METER MOVEMENTS/READINGS BETWEEN CHANNELS. THIS SHOULD TELL YOU THAT ONE CHANNEL IS ASLEEP OR SMOKED, OR NOT... If NEITHER channel produces any movement with your AC voltmeter, then your meter is unsuitable for this method of test. BUT MOST ANY METER SHOULD BE ABLE TO TELL YOU SOMETHING. Start out with it around the 2volts fullscale setting and then slowing turn up the music. IF you get nothing, lower the scale to a more sensitive setting. Again, an A-B test between the good and bad channels should tell you a LOT!

After that, connecting any cheap speaker to the speaker level outputs of ANY OF THE AMPS should produce music. USE one of the old BLOSE speakers on a short set of speaker wire to test these amp outputs.

IF YOUR VOLTMETER TESTS ON THE "LINE LEVEL" SIGNALS SHOW THAT SIGNALS ARE PRESENT ON THE INPUT OF AN AMP... OR ON THE OUTPUT OF A LINE LEVEL HU OR EQ... and the amps output does not produce any music into a hobby speaker... then you have just proven that your amp is dead. If, however, you find a missing signal somewhere... then you have some more troubleshooting to do with wiring, or connectors, or configurations of the device in question.

PULL UP... PULL UP... You can recover from this nosedive. I just hope it doesn't cost you an arm and a leg. If the NEW amp is found defective, that should be covered by warranty. If the subamp was indeed bad, your new JL amp should fix things. But part of me can't help but hope that there is something in common causing BOTH problems that can be solved without replacing amps?????

As usual... GOOD LUCK!
Southbound

systek

SB is right, your initial post sounds like the left front channel on ur 4 channel amp and left channel sub amp went bad at the same time. yet you posted that you only replaced the sub amp. please clarify cause if there is something else causing the failure, i'd hate to hear your newly purchased amp goes by the wayside as well...

bozzchem

Front amp is fine. Left side works great when I swapped the front and rear patch cords. The front left speaker played fine when I used the patch cord I was using for the rear. The front left patch cable didn't work anywhere I tried it.

Patch cables are bad. I shouldn't have even used them.

DO NOT BUY THE TRIPLE SHIELDED cables from Carmedia1. One set broke on me just trying to get them out of the package!! I'd guess the wire guage to be 24 or greater from looking at it. Hell, it looked like thread!! I don't know if that's normal...but they looked really flimsy. They sent me a new one free. I'm guessing they get a lot of complaints about them.

There's $50 down the toilet.

I still can't get the sub amp to work properly. I'll play with it more this weekend. I need to order some new cables now.

Thanks all.

Southbound

Thanks for clearing things up. It does appear that your only problem now is with the subamp or the feed from the EQ or HU to the subamp.

Good luck... You're on the right path!
Southbound

bozzchem

Thanks SB.

I'm convinced it's not the HU or the EQ based on the other troubleshooting I've done. The right woofer plays great whether the L or R patch cord from the sub out of the HU is connected to the R input of the amp. Neither plays when the R or L patch cord from the HU is connected to the L input of the amp. The L sub plays great when I swap it to the R output of the amp. I think the L out has given up the ghost...so to speak.

I've ordered new interconnects for the whole system. I should have known better when I ordered the ones I did. They weren't cheap but they weren't expensive. However, they WERE a no-name brand.

Live and learn. I'm happy that the front amp is good. It still sucks that my sub amp is bad, but the new one is much more powerful as well as requiring less amperage draw from my alternator since it is a class D amp.

BTW, have you ever heard of a term called "motorboating"? I heard this term years ago when a speaker starts making a constant sound that resembles that of an intermittent motor sound. The reason I ask is that I noticed that when I had both patch cords feeding the sub amp, the right woofer hit well. However, when I removed the left patch cord, the woofers started "motorboating".

Assuming you're not familiar with the term, it's a constant bump at the same interval. I could explain it better with sound than I can do so with words. Picture a constant bump sound over and over at the same time interval.

Based on your knowledge of amplifiers, I'm figuring there's a good chance you've experienced this but may have heard it called something different.

I guess after hearing it I thought it was the final nail in the coffin of my amp.

The last time I heard it was back in the old days (early-mid 80's) when Crutchfield sold amps with their name on them. I had an Alphasonik EQ that was shorted out by a Crutchfield amp and the speakers just "motorboated" when it was hooked up. (I got the term from the Crutchfield rep I spoke with on the phone)

Funny how there are no longer Crutchfield amps isn't it? They lasted a grand total of about three years. Even less funny is how they touted that my EQ needed a floating ground and that it was the EQ that was bad and not the Crutchfield amp. I took the EQ to a local shop and they told me it was fried.

I didn't order from Crutchfield again for about 9 years. Go figure

Southbound

bozz,
Your first paragraph from your post above does indeed confirm that something is wrong with the LEFT SUBAMP CHANNEL. You clearly explained your troublshooting techniques, and they are exactly the way that I would have proceeded.

The term "motorboating" is indeed a common amplifier/speaker anomalie. What it actually is, is a LOW frequency type of oscillation. It usually occurs whenever an amp has a defective power supply, or defective decoupling circuits between stages of amplification. It can also happpen very commonly whenever you have a ground loop situation or lack of proper grounding, etc. Sometimes it's a bit hard to pin down as to the actual cause.

The motorboating occurs as a result of insufficient power supply decoupling or improper grounding between the input and output of the amps BALANCED signal. It can also be produced by an amp that has lost its ability to provide current into the load. This would happen if all of part of the output transistors have popped. The amp can bias up and provide a voltage output... but as soon as it is applied to a load, it folds back and shuts down. First, The amplifier circuits bias up normally and begin to produce sound into the speaker. As soon as the speaker begins to draw current, the amplifier becomes improperly biased and shuts down... As soon as it shuts down, the speaker quits drawing current. As soon as the speaker stops drawing current, the amplifier bias comes back up to normal... as soon as this happens, it begins to feed the speaker again. The speaker current again unbiases the amp and it shuts back down... THIS CYCLE continues to go on and on thus producing the "motorboating" sound.

The system will continue to motorboat until the cause for why it becomes unstable is determined. Basically, in this case, the amp is in a situation where it is unable to provide enough current gain to provide a constant source of current to the low impedance speaker load.... Meanwhile, it has the capability of producing a high voltage gain which causes it to keep trying over and over again. As stated before, This can be due to bad filtering or decoupling in the amps power supply, A bad high gain voltage stage, a bad high gain current OUTPUT stage (most likely), or a myriad of grounding problems. The higher the gain of the amp... the more important the grounding becomes. Especially if you are dealing with a "balanced" input and an "Unbalanced" speaker output.

Replacing your amp with a new one sounds like it should cure your ills. As you are doing, REPLACING ALL OF YOUR RCA CABLES could also cure your ills. There could be a bad shield/ground connection on one of the cables which requires you to need BOTH cables installed to keep the amplifier grounded properly. One quick check for that condition would be to make sure that the amp motorboats regardless of which SINGLE cable you have connected to the output. It may be that it will work fine with ONE of the GOOD cables???

One last issue of confusion for me... How are your TWO SUB WOOFERS connected to the subamp? Do you have two separate subamp outputs feeding two separate subwoofers? OR do you somehow have the two subwoofers connected in SERIES and then bridged across the two outputs of your subamp?

If the former is the case, then everything should be straight forward to troubleshoot and replace, etc. If the latter is the case, you could have some more internal amplifier phasing issues that would come into play and cause your amplifier problems. You can't simply go across the two outputs of a dual channel amp and make it behave as a mono bridged amp. You have to reverse the phase of one of the output stages INSIDE the amp (USUALLY WITH A MONO/BRIDGED SWITCH LOCATED SOMEWHERE ON THE AMP) in order for it to work in a mono bridged mode. Make sure that this issue isn't at the root of your problems...

As always, GOOD LUCK! Happy fishing with your new MOTORBOAT!

Southbound

bozzchem

Wow, you never cease to amaze me.

As far as my sub config goes, they are (were!) configured in 2 ohm stereo. Each sub got its own 2 ohm feed from a separate I/O channel. No bridging whatsoever. That's what made it so easy to troubleshoot. Both RCA cables made the right sub work. Neither RCA cable made the left sub work. Pretty much cut and dried in my book. I'd just love to know what the hell happened between cars?!?!?

For some strange reason, my amp has died. If I had the equipment, I'd love to troubleshoot it to see what happened to the left channel. It worked great in my previous car, sat in my office for 4 months, and croaked upon installation to the TLS.

As I stated earlier, ALL of my RCAs are going to be replaced. The new ones should be here by Tuesday. Now I've got to pull all of the seats out again......etc.

Once the JBL amp gets here, the system will be configured differently. I'm going to configure the two subs to present a single 4ohm mono load.

The amp is rated for 600W x 1 @4ohm. I could go with a 2ohm load but I don't really see the need for 1200W AND I don't want to place the added stress on the alternator.

Thanks again for all of your help.

This will be another one of your messages saved to my favorites.

Cheers!
Pete

Southbound

Thanks bozz,
Sounds like the amp definitely crapped on you. The only thing that is typical to happen when you let a used amp set idle for several years, is that some or sometimes a lot of the electrolytic capacitors will dry out and become either leaky or essentially appear open without any signs of capacitance left in them.

Sorry for your bummer in progress... but the new amp should have you hooked up!
Good Luck!
Southbound

bozzchem

The sad thing is that it only sat idle for about 4 months.

Oh well, stuff happens. It did have a tendency to overheat during the summers here in NC. I hope the class D amp won't let me down. Based on the reviews of it I've read, it seemed to provide the best cost/watt ratio of any quality amp available.

I guess I'll find out next weekend!

Thanks again to all who have helped.