Posted November 3, 201014 yr Hi guys, my sub amp (Soundstream 2000 monobock) is acting weird. You will hear the subs pop out and then the amp goes into protect. Any time of day, any volume level, music/no music. It's totally random. Just wondering if any of you would have any ideas. I have 165A alternator (stock), 1/0Ga wire to amp. The batt meter on the car stays at 14 volts. The gain on the amp is all the way down. No bass boost. It also seems random when the amp resets itself so I can begin to use it again. Let me know if you need any more info. I'm also wondering if my subs could be the problem. They are dual 3 ohm wired in series to 6 ohm per speaker input (there are 2 on amp). The speakers wired in paralell should have a final load of 3 ohms. The amp has an auto ohm calibrater with 4/2/1 ohm settings. After calibration it sets itself to 4 ohms. Could one of the coils went out on a sub causing a different ohm load? Thanks for any help you can give me.
November 3, 201014 yr Author Measure RCA voltage at the amplifier when this happensDaaaamn, thanks for the fast reply!
November 3, 201014 yr "Could one of the coils went out on a sub causing a different ohm load?" verify the ohm reading of the subs @ the amp to eliminate that as a problem as well.
November 4, 201014 yr I suspect something lose inside the amplifier, considering it goes into protect. Driver board maybe. RCA voltage will not put it into protect. Shake it and see what happens. I'd stop using it and find out what is wrong.
November 6, 201014 yr Author *Update* I followed all the advice you guys gave me and nothing worked. voltage was fine, RCAs were fine and nothing rattled when I shook it. When the amp went into protect again I unhooked 1 speaker and the amp came back on! woohoo. I measured the ohms at the box and got 6 ohms/speaker. I then measured at the amp and goe 1.5/speaker. That confused me a little bit but I continued on and wired the subs in parallel. The amp stayed out of protect and pounded HARD. I should have but I didn't take a final ohm measurement at the amp. I'll have to wait and see if it stay out of protect. The way I installed everything, it is impossible to check anything. I'm going out for a road trip to see if the amp will be "normal" now.
November 6, 201014 yr Author Well that was a short trip. The amp is still being dumb. I also switched RCA cables to rule that out. My only other option is to just run 1 speaker at a time to eliminate each speaker. After that it only leads me to believe the amp is bad for some f*ed up reason If there is anyone that lives near me, I would drive to your place to get this figured out. (98GMC, or ///////////////M5) Anyone else near Montevideo, MN?
November 6, 201014 yr Do you have another amp to try on the subs. Sounds like the amp itself as it's intermittent. Maybe contact Soundstream Technical.
November 6, 201014 yr Author Do you have another amp to try on the subs.No I don't. If I'm getting good ohm readings from the subs then wouldn't I need to have other subs to try on the amp? I don't have that either! Bah!! Maybe contact Soundstream Technical.I just might have to do that.
November 6, 201014 yr Check each voice coil at the speaker first. If they check fine then it is most likely the amp. As Adrian said above probably a driver board or a bad trace on the board.
November 6, 201014 yr *Update* I followed all the advice you guys gave me and nothing worked. voltage was fine, RCAs were fine and nothing rattled when I shook it. When the amp went into protect again I unhooked 1 speaker and the amp came back on! woohoo. I measured the ohms at the box and got 6 ohms/speaker. I then measured at the amp and goe 1.5/speaker. That confused me a little bit but I continued on and wired the subs in parallel. The amp stayed out of protect and pounded HARD. I should have but I didn't take a final ohm measurement at the amp. I'll have to wait and see if it stay out of protect. The way I installed everything, it is impossible to check anything. I'm going out for a road trip to see if the amp will be "normal" now.You need to shake it with it turned on and connected. An improper joint at the driver board will not make sound when shaking it. If you feel so inclined, open it up, take a picture and I'll show you what components to check visually.
November 6, 201014 yr Author I got these off ROE as it was easier. I think that the little board on this last pic here is what you're reffering to. I'll have to take a batter pic of that tomorrow
November 7, 201014 yr With the amp powered on NOT playing music, (on pause) connect your DMM to the speaker leads at the amp, push on the cone of each sub 1 at a time and see if the ohm reading changes, I have heard of your problem before, an in that situation it was a short in the vc/ solder join on the terminal.
November 7, 201014 yr With the amp powered on NOT playing music, (on pause) connect your DMM to the speaker leads at the amp, push on the cone of each sub 1 at a time and see if the ohm reading changes, I have heard of your problem before, an in that situation it was a short in the vc/ solder join on the terminal.The readings are going to change as the coil moves in and out of the magnetic gap. Really not going to be able to tell unless it reads 0000.
November 7, 201014 yr By checking the DCR on each coil! If it reads something way off from spec, it's messed up.
November 7, 201014 yr Yes I understand that aspect, but what if the sub reads fine with the dmm pushed into the terminals, but you push on it and there is a short. I guess its harder to explain then show, but the tensil lead could be loose, multiple things, but it sounds like a short which is changed the imp causing the amp to protect.
November 7, 201014 yr By checking the DCR on each coil! If it reads something way off from spec, it's messed up.Tough to tell by DCR. Best option to check for shorted voice coils is to measure inductance. Duran, from any pics, it's hard to tell a bad solder joint or connection OP..is that extra board the one with the rca inputs and setting knobs ? Triple check the connectors and wires on that. I had an amp that was on and off erratically, turned out to be a bad wire in a plug. Look for any components that are not soldered in. I see a few integrated circuits on the sides, can't tell if they are soldered or on sockets.
November 8, 201014 yr Your DCR measuring tactics are confusing the hell out of me. Measuring at the box and at the amp is the SAME thing.. same wire.. etc...Unhook ALL speaker connections going to that amps and unhook ALL coils going to each other.Measure EACH coil (4 total) and see what it reads...Then wire in series each sub and see what it reads...Then parallel them and see what it reads.
November 8, 201014 yr Author Ok, took some time today to take some readings. Heres what I gotThis one is from the manual on how to hook them up All the tinsel leads had no signs of breakage I wanna say thanks alot for all the help given so far. I'll get my camera back tonight so I can take pics of the insides of the amp. ( 98GMC Hows tomorrow looking for a visit)
November 8, 201014 yr unless u wired\types it wrong, there is a problem with the diagram that shows final load of 1.8ohms...that diagram shows 2 subs being wired in parallel all the way to the amp.Using 2 dual 3.2ohm subs, a final parallel wire load should be - 0.8ohms, not 1.8ohms.. . Something is not right there.
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