New Build Issues

[Chaos1187 10+ year member]

Equipment Used:

320 Amp Mechman Alt (Voltage set to run 14.8 when hot @ 2k rpm)

Factory BMW Sealed Lead + XS Power D3400

KnuKoncepts 0 Guage Wire Throughout

RF bd1000.1 (SUBS) and RF 450.4 (DOORS)

New RCAs throughout

Alpine HU

First Problem Under acceleration to take off from a stop, the door speakers cut out for a second. Then turn right back on. Only under acceleration. I have checked voltage and for a split second here and there it does "spike" and hit into the 15 volts for like a split second. Didnt know if maybe the amp is just hitting protect because of it. Reason i say that is once the car is hot it tends to stop doing it. (I recently went back in and set the voltage to run 14.8 when hot, I changed it because I noticed once the car was hot voltage would read only like 14.3 or so)

Second Problem I have set my gains with the SMD DD-1 distortion meter (HU and AMPs) So I know my system begins to distort once I hit volume 30 so I use 28 as my peak. Well at around volume 20 to 24 which sounds pretty good my subs cut out. This weekend I was hammering on them. I noticed a little sound tapping, slapping noise from one sub under close observation of sub, amps, etc. Amp does not go into protect when this occurs only sub cuts out.

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[kenwood23]

sounds to me like they are starting to clip, which will eventually blow the sub. clipping is when the voice coil gets worn out and rubs the voice coil walls. hope this helps!

 

[Flex68 10+ year member]

sounds to me like they are starting to clip. Yes, very possible.clipping is when the voice coil gets worn out and rubs the voice coil walls. uh, no: clipping has to do with the signal, not the mechanics of the sub, itself.

Recheck your output voltage settings, OP. I would suggest you reduce the gain, regardless, and see if this corrects the problems...

 

[kenwood23]

Guys be sure to check out my thread kenwood tornadoes? i need advice!

 

[Full Tilt 10+ year member]

sounds to me like they are starting to clip, which will eventually blow the sub. clipping is when the voice coil gets worn out and rubs the voice coil walls. hope this helps!

lulz

Seriously, clipping might be an issue. But as Flex pointed out, clipping has nothing to do with the mechanics of the subwoofer. Do you have an oscillosocope available? You could check for clipping with one of those.

 

[Chaos1187 10+ year member]

lulz
Seriously, clipping might be an issue. But as Flex pointed out, clipping has nothing to do with the mechanics of the subwoofer. Do you have an oscillosocope available? You could check for clipping with one of those.

I do not //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif I just ran through the DD-1 manual and setup my gains with the DD-1. But from what it sounds like as far as Problem 2 goes is that the sub has played some of its last tunes mechanically worn?? The other sub is hooked up to the same amp (monoblock) does not make any noises but the bassy goodness at these same volumes. Would it cause both subs to cut out? even though the amp during this time shows the regular blue "on" status?

Any other thoughts? Maybe with other problem?

 

[All_Logix 10+ year member]

I would give mechman a call about the voltage problem, sounds like the sudden change in the rotation of the alt's internals is causing some sort of inrush, could be a problem with the voltage regulator. One of the most common problems I have seen with HO alts is how they react to varying rotational speeds.

 

[Chaos1187 10+ year member]

I would give mechman a call about the voltage problem, sounds like the sudden change in the rotation of the alt's internals is causing some sort of inrush, could be a problem with the voltage regulator. One of the most common problems I have seen with HO alts is how they react to varying rotational speeds.

Isnt it normal for the alt to jump up in voltage for a brief second? after that it idles and revs both to where r within operating limits? Only reason i ask is the regulator is 2 weeks old. And reads out fine.

 

[Falcons 5,000+ posts]

I'm thinkin you set your gains using a -3db test tone or more and to are playing songs that's lay greater than -3db which even though when you set your gains on your amp, it is to the -3db tones. But if you play doings that are louder than that, you can very well still be clipping.

 

[All_Logix 10+ year member]

Isnt it normal for the alt to jump up in voltage for a brief second? after that it idles and revs both to where r within operating limits? Only reason i ask is the regulator is 2 weeks old. And reads out fine.

It will change slightly but I dont think it should be getting that high

 

[Chaos1187 10+ year member]

I'm thinkin you set your gains using a -3db test tone or more and to are playing songs that's lay greater than -3db which even though when you set your gains on your amp, it is to the -3db tones. But if you play doings that are louder than that, you can very well still be clipping.

When setting it up I used a -10db track a compromise between SQ and SPL. As for clipping I strongly doubt it could be a factor. These subs are wired down to .5ohm The voltage stays in the 14.0 range would be suprised to see it hit lower then 14. The voltage to me doesnt fluctuate like I imagine it would at a .5 ohm load that is clipping. The RF amp gets warm at best during all of this. Gains havent been set with a scope just the DD-1 but repeatedly checked and checked again, while watching voltage etc.

I took the car out for a cruise watched my voltage during all my bassing / driving. Lowest voltage was at idle 13.x range. The cutting off happens in different songs (bass heavy ones) and at loud volumes only. Another reason for not thinking it is clipping. It cut out at 24 so I turned it up to 26 and jammed it till I got a little deaf and turned it down. Didnt cut out again during the louder playing. Different track volume 24 "Playing with fire" (lil wayne song) heavy bass lines....cut off. Turn it up plays for a while cuts out randomly (voltage stays good). Music never stay off but a second or two, and amp doesnt get hot, a regular warm at best.

 

[Chaos1187 10+ year member]

It will change slightly but I dont think it should be getting that high

Waiting to get a hold of mechman bro

 

[MECHMAN 10+ year member]

15v is normal for many alternators when cold. Briefly going that high, then settling down to 14.8v is totally within spec.

You need to isolate the problem, figure out what exactly is turning off, and diagnose from there.

 

[Chaos1187 10+ year member]

15v is normal for many alternators when cold. Briefly going that high, then settling down to 14.8v is totally within spec.
You need to isolate the problem, figure out what exactly is turning off, and diagnose from there.

Mechman I left you a message to check with you! Thanks for everything you have done, your product is amazing! As well since you are here, do you think the fact that this happens when cold (Problem 1) is just the amp not being able to handle a 15+ volt, so it cuts off for that brief second that it hits around there??

any input on problem 2??

 

[Chaos1187 10+ year member]

BUMP

any more input?