I now have a thump when I didn't before (MKII #335). Here's what I did:

I got a CD/Radio which I wanted to switch on with empeg, not the ignition. I installed this a few days ago and all had been going great, no thumps, could power up empeg after the key came out (radio was wired to ignition switch)

Today, wanting to get the radio to switch with the empeg I crimped the radio's switched power lead (red)in with the amp turn on lead (blue). I left the radio's full time 12 V (yellow) alone.

I turned on the ignition to position 2 (acc power). The empeg & radio turn on. I switched the key back to position 1 (no acc power) and the empeg turned off with a blinking LED. I turned the empeg on with the LH top button. The radio came on as well. All's good at this point.

With the empeg still on I put in the key and started the car's engine. Still good.

I switched the engine off and THUD. Now every time I switch between key position 2 and 1 (1 is just after the postion where you can remove the key) I get a thud. The continuous power line is still 12V (I checked). The switched lead goes from 12V to 0V when the key turns from 2 to 1 (I checked). So what is it?

I have the developer kernel 1.0 installed as well as the voladj kernel.

I'm willing to check anything (have multimeter, will travel), but as it worked once but then quit it sure feels like it might be a bug.

I wired it back the way it had been before (took radio switched lead off amp wire) and it still thumped. I checked the memory lead fuse & continuity, still good.

After a few more checks I can with certainty say that the memory lead stays +12V the whole time (measured inside the sled) and the switched lead goes from +12V to 0 when the key is switched from position 2 to 1.

(a very confused)
-Zeke

just say you weren't paying much attention...

Aha! I've got an iffy crimp on the back of sled on the orange lead. I'll be contacting empeg customer service soon. I can wiggle the orange wire where it enters the back of th sled and get continuity on and off. This must be the problem. I wonder if this has happened to others.

-Zeke

just say you weren't paying much attention...

I crimped the radio's switched power lead (red)in with the amp turn on lead (blue).

You what? Argh, no wonder you're having troubles. I think you should just activate the CB radio and the Empeg separately and not worry about it.

___________
Tony Fabris

Sorry it took so long for me to respond to this--- but I checked and double checked my power connections and they are all correct. I am however running the .99 version of the player (I haven't received my serial cable yet to upgrade it to 1.0). Could this be part of the problem?

My second post was completely wrong. The orange crimp on the sled is OK (the socket was moving away from my test lead when I wiggled).

No, Tony, the red is the switched lead for the Kenwood CD/radio (not CB) and it also has a yellow full-time power wire, which is hooked up with the empeg's to the full time from the harness. It thumps even when I cut the red radio lead out entirely.

Needless to say I'm pretty frustrated, and here's the weird bit: I can remove the car's fuse which is for the empeg's switched lead when the keys are in position two. The empeg shuts down gracefully (into sleep mode) and no thump. If I use the keys to turn off the switched lead, thump & the unit quits hard (display right out & no LED). All I can figure is a spike is going through when I use the keys. My multimeter doesn't pick anything up, but it's pretty slow (digital).

Does anybody have a suggestion for a good cap value to try to test my spike theory?

-Zeke


just say you weren't paying much attention...

A note for eyee: I reprogrammed my unit from MKII 1.0 developer to MKII 1.0 consumer & there was no change in the thump behavior (FWIW).

-Zeke

just say you weren't paying much attention...

Does anybody have a suggestion for a good cap value to try to test my spike theory?

Well, I have an entire thread on the subject of caps and stuff here, but my concern is that you started off with no thump problem, then you started having a thump when you tried wiring your radio power to the Empeg's amp remote. You shouldn't need to wire any capacitors with the Mark 2 unless something else is wrong.

I fear that by wiring a high-amperage line (the red lead from your other stereo) to the relatively low-capacity amp remote line (on the empeg), you may have damaged something which is making the thump happen now.

Can you draw us a diagram of the system's wiring scheme and post it here so we can see what we're dealing with?

If you still want to go the capacitor route, remember that you need a rectifier/diode as well. Here are the capacitor values, and here is the proper schematic as to how to wire them with the diodes. Although this is a simplified wiring diagram for an empeg-only installation. Yours would be much more complicated since you have multiple head units.

___________
Tony Fabris

I am however running the .99 version of the player (I haven't received my serial cable yet to upgrade it to 1.0). Could this be part of the problem?

I'm not sure. Possibly. If upgrading to 1.0 solves the problem, make sure you post that information here.

When you checked your wiring, did you get out the Empeg user's manual and look at the color-coding of the cables? Did you use a voltmeter on the car's wires to make sure that continuous power was really continuous, and that the ignition wire really switched properly?

___________
Tony Fabris

I crimped the radio's switched power lead (red)in with the amp turn on lead (blue).

You should be very careful doing things like this, as the switched power lead is not intended to supply any significant current (I believe it's fused at 1A). Since it's the accessory input to the radio it MIGHT not take much current, but some head units actually power up through the switched input and only use the permanant power feed to preserve memory.

Have you checked the current rating for that power line on your CD head?

Hugo will probably have to think about the thump problem - if it didn't do it originally, and now it does it after returning the configuration to the original state, SOMETHING must have changed.

Rob

Danger will robinson! The empeg +12v amp switched line will supply a MAXIMUM of 1A. Powering your CD head unit from this is *NOT* a good idea - it *will* probably blow the internal fuse in the empeg (which is resettable if you leave it for 10 minutes or so to cool down).

This probably accounts for your problem - the head unit is drawing so much current that the amp remote line is being dragged down and causing a "blip" which makes the amps thump.

If you want this setup, use a relay on the amp remote line to switch a permanent 12v line into the accessory power input of your CD head unit.

Hugo

This morning's progress:

Step 1: Cut CD/Radio switched power lead out of Amp relay circuit. Now empeg is wired exactly as it had been all week (with no thump).

Step 2: Slide empeg into sled.

Step 3: turn keys to positon 2 (acc power on). empeg starts up & plays.

Step 4: turn keys to positon 1. Thump.

Step 5: turn keys back to position 2, let empeg begin playing.

Step 6: pull fuse that controls switched power line. No thump and there was a correct LED & shutdown.

Results of the multimeter: switching the keys from 2 to 1 drops the switch power line to 0.001/0.000 VDC. Removing the fuse (with key in position 2) drops the switched power line to 0.030 VDC. Hmmmm. I checked all voltages at the sled, so I'm certain there's no continuity issues. I also confirmed the switched line voltage at the vehicle harness (empeg & radio harness disconnected) to be sure the something wasn't backdriving the switched line that 0.03V.

I also checked the load from the amps (two 2 channel amps) on the blue lead at 0.22-0.23 A, well within the 1A limit.

I think my next step may be to get a relay as Hugo suggested but use it for the switched power line (ie command line side from key switch and switched side between permanent 12V and empeg's switched 12V line). Further, if this helps the thump I'm going to get another relay and put its control lines on the amp line and the power side from permanent 12V to the switched power into the CD/Radio to achieve my original goal.

A thought on the didn't thump before, does now situation: most times I'm not switching the unit on/off multiple times. So, if it didn't thump the 1st time, I wouldn't have noticed it. However, it did thump 1st time round this morning, so I'm not sure what to think.

Thoughts?

-Zeke

ps: for what other product is a company principal going to answer a question on Sunday morning? -NONE-

just say you weren't paying much attention...

Hmm, I may have a related problem. I get the same boom while turning off the car. I thought at first that I had a wiring issue or that my 12volt constant lead might not be that constant. Then something weird happened. For 1 day everything worked fine, no thumps. I turned the car on and off several times with zero problems. The next day the thumps where back.

I have not had a chance to tear apart the wiring yet, but I am reasonably certain that my connections are solid (they are all soldered and encased in shrink tubing. I have the remote turn on leads for two amps running from the empegs remote lead. I am probably going to check the wiring this afternoon, so I will post back if I turn up anything.

-Mike

Radio Shack 12V/30A automotive relay P/N 275-0226 SOLVED MY THUMP!!!

How to wire it: Put the switched line from the car harness into the on/off, the car harness ground to the ground terminal, the 12V constant into the 12V in and the empeg switched lead into the 12V out. VOILA. NO THUMP!!!! (can you tell I'm a little excited?)

I don't know for sure why it solved my thump (I'll stick with my voltage spike theory), but there it is. There must be _something_ about how the keyswitch was dropping the voltage from 12 to 0, otherwise what explains the fuse pull/keyswitch difference I observed? Any electrical engineers in the audience tonight? I'm just one happy camper. The stats on the relay can be found below:

http://www.radioshack.com/ProductSupport/DocumentDetail/Index/1,2360,,00.html?Doc=/support_auto/doc38/38002.htm

Since it draws only 160mA I'm going to put my 2nd one in the amp output line to switch my Kenwood head unit.

joy!

-Zeke

just say you weren't paying much attention...

Kenwood CD/Radio & empeg are both relayed & working wonderfully. I can't imagine I'm the only one who would try to set a second head unit as slave to turn on/off with empeg, maybe a FAQ on this subject? Now, about that clogged washer drain & flooded basement floor....

-Zeke

just say you weren't paying much attention...

Yep, definately appear to have a bug with the empeg here. I verified my wiring. The 12 volt constant is staying at 12 volts (consantly ;) and the accessory lead is turning off with the vehicle. And yet, the empeg shuts off abrubtly when the car drops power on the accesory lead and I get a thump as a result. If I physically remove power from the accesory lead the empeg shuts down gracefully as expected.

Is it possible that the empeg expects the accesory lead to go all the way to zero volts and if it stays just a bit above that the empeg shuts off abrubtly causing a thump?

For now I have wired memory and accessory to my car's constant on line so that the empeg stays on to avoid this thump.

Oh, by the way, the empegs memory appears to get cleared when it shuts off with a thump. I lose my playlist or position in the playlist as well as fader and equalizer settings.

-Mike

Oh, by the way, the empegs memory appears to get cleared when it shuts off with a thump. I lose my playlist or position in the playlist as well as fader and equalizer settings.

This indicates something serious going wrong with the power feed to the Empeg (or as you suggested, something possibly wrong with the Empeg itself). This is what happens when the Empeg gets a "powerfail" state, and it is not the intended behavior.

Can you make us a wiring diagram of how everything is hooked up, including amps, etc.? Maybe there's something obvious we can debug for you.

___________
Tony Fabris

Tony, I don't really think a wiring diagram is necessary as I disconnected everything in the process of testing. At one point the only three wires I had connected to the empeg where ground, 12v constant, 12v accessory.

I verified (with one of those automotive probes with the test light in it) that the 12v constant feed was always on and that the 12v accessory feed was going on and off with the key as one would expect. Whenever I shut off the ignition the empeg goes into the 'powerfail' state you mentioned. If I simply disconnected the accessory wire the empeg did a gracefull shutdown.

I also tried running the 12v constant feed straight to the battery with the same results.

I think this isolates it to the 12v accesory feed which is going on and off, but with my limited on hand testing gear, I can not determine the exact voltage level of the "off" state. Maybe I will try to dig up a multimeter tomorrow to determince exactly what is happening with the accesory line. For now, it seems to me that the line may be in some intermediate state between full on and full off that is confusing the empeg. Been a few years since my last electrical engineering course, but I think there is even a name for that :-)

Any of the empeg hardware dudes want to chime in and tell me if that is a possibility?

-Mike

For now, it seems to me that the line may be in some intermediate state between full on and full off that is confusing the empeg. Been a few years since my last electrical engineering course, but I think there is even a name for that :-)

YES!!! It's called "Debounce"!

You may have hit on something!

Hugo, is the sense on the 12v switched line debounced?!?

___________
Tony Fabris

I can't see how this would happen: obviously, it's a binary input so can either be 1 or 0. If it's 1, the empeg stays powered. If it goes to 0, the empeg *still* stays powered (as long as the permanent 12v feed does not go away *at all*). The empeg turning off is a *software* action - for example, if you quit the player then turn the ignition off, the empeg will stay on forever. This is how the configurable software delay works.

The fact that your player turns off suddenly sounds very much like a glitch in the permanent 12v line when the accessory input is also low.

I'd like to verify this with some proper test gear (ie, dual channel storage scope) but we can't replicate the problem on my MX5, beetle, or the empeg a-class. Steve hasn't reported any problems either on his Volvo :(

Hugo

See my last message - it's not debounced, but doesn't have to be as powering off is a software action. I've tried to reproduce some bounce (our dashboard we use for shows has switches in both main and accessory power lines) but I'll try again. Maybe there's a race condition in the player which is causing the problem.

Actually, this might give me useful info. Can someone with the problem hook up a laptop in-car (you will need to ensure the laptop gnd is the same as the car ground due to the missing pin on the in-car serial connector :( ), quit the player, then turn the ignition off and see if the empeg dies? If it stays on, it's a software fault...

Hugo

But you could drive a relais with the amp remote - line. And the relais switches the direct battery-power to the CD-headunit. That's the same thing amps do.

TeeMcBee
Got my Mk2! # 080000143

Ooopss - as I just read you've already done this by now... sorry..

TeeMcBee
Got my Mk2! # 080000143

I might be able to hook up a laptop this week if I can sneak one out of the office for a night. Can you tell me specifically how to ensure the laptop is grounded directly to the car? I'll have to take my relay out, but this is not a big deal.

-Zeke

just say you weren't paying much attention...

Mike,

You wrote:
"And yet, the empeg shuts off abruptly when the car drops power on the accesory lead and I get a thump as a result. If I physically remove power from the accesory lead the empeg shuts down gracefully as expected."
This is precisely the behavior I observed.

You also wrote:
"...the empegs memory appears to get cleared when it shuts off with a thump. I lose my playlist or position in the playlist as well as fader and equalizer settings."

This also happened on my unit when the player dropped after a keyswitch with a thump.

Repeatability is a wonderful thing.

My vehicle is a 99 Subaru Forrester S that came equipped with (HA!) "premium sound package" (radio/tape head and single CD player slave).

-Zeke


just say you weren't paying much attention...

Hugo,

you write: "...sounds very much like a glitch in the permanent 12v line when the accessory input is also low."

This thought does not jibe with my relay solution. I did not change the permanent 12V input line, just the switched line. It also doesn't match with Mike & my observations about proper operation when power is manualy removed from the switched 12V line (ie it works properly).

You say that the power is at either 0 or 1 (0 or 12 V). In reality the shutoff is never going to be a nice square wave. (Not knowing how you have things set up on the inside...) Could it be that depending on when the voltage level is sampled it may not be this simple and this is misinterpreted by software as a powerfail? It just seems that the behavior of the empeg is affected the quality/shape of the 12V to 0 step down. Or, perhaps the strange step down pulls the ground level of the empeg up briefly so that the empeg thinks it's getting less than 12V from the unswitched main? I don't know how things are laid out in there and I'm just spitballing possibilities.


-Zeke


just say you weren't paying much attention...

This is the exact problem I had earlier. I posted how I fixed it in this message. When I was doing testing I did just about everything except quit the player and see if it would stay alive.

-Finally received my Mark2 no thanks to customs.

I've yet to read anything in this thread that says where you have connected your car cables too on your empeg. Are you sure you have 12V (perm) going to the 12 V (perm input, empeg), the 12V (switched) going to the 12 V (switched input, empeg), and ground-ground? You haven't for example connected the switched lead to the empeg Accessory control (output) line?

Are you using an ISO connector or splicing in?

One of the few remaining Mk1 owners... #00015

If you're suffering from this problem, please refer to the thread I started in the Technical forum.

Thanks.