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Sundown sae1500d's and sa15's output

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Hay guys i got two questions about my setup. 2011 f150 with factory charging system with extra 1000 cca marine batterie "not a audio battery". I'm running 2 sae1500d amp on 4 sa15 subs. They are the rev3's and are 2ohm coil's. I am running the amps seperat gain matched "to the best of my ability" and I'm at . 5 ohms at each amp not counting rise. I have the rear seat out and built a good sturdy enclosure that's sealed good with a port that's tuned to 35 hertz. I'm over the recommend size on the enclosure I know at 19 cubes total shared air space but i did that do to the fact that i wasn't running very big setup on the amps, i know there getting the rated rms power but i also know that's not near what these guys can handle if it's clean. My question is what kind of numbers should i be getting with this setup? I don't believe something is right because I'm getting a 138 to 140. Had some issues straped where they kept going into protection mode so went back to running them separate and it still did it until I fixed it somhow mysteriously lol They will still go into protection seperstly but only at a lot higher volume than when they where strapped at 1 ohms. But it seems they are slowly going into protection mode sooner and sooner but it could be me thinking that. Any help would be awsome. 

Ps the box isant the issue unless it's do to size or porting or possible center port location other than thatnit's rock solid.  I used a special sealer on and inbetween each piece of mdf and used 4 3/4 layers of mdf on all sides not just the baffel and i used 2/6s to brace it front to back back to too Bottom bottom to top twice over. And liquid nailed and sealed all corners with sealent 

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The enclosure design is about the most important thing in an audio setup especially trying to get higher numbers . So even if the enclosure is buit the best it possibly could if the design isnt good it will not do/sound good. The enclosure definitely is an issue as its not designed for the subs . . . . .  Have you been monitoring your voltage while bumping? Cause I bet pretty bad voltage drop is causing the amps to protect more than having them at .5 each. 

Sould be able to get at least in the mid 40s with what your running

 

Edited by frogcase2002

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Yea I got a dual 12 set up hitting 143 in my jeep. Like frogcase said, design plays a huge factor. And 4 15s in a truck should be bumping. Is it a wall or blow through?

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Also how much port area is there?

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My other worry, as you also stated, is about the amplifiers seeming to not handle the loads like they used to.  

The SAE line was never designed to be as robust as the SAZ line in the first place. More of a budget friendly option while still very solidly built was the goal I believe. You’ve been running them below their minimum rated impedance and while you have some upgraded electrical I am not certain it’s enough to properly feed those under that kind of load. I’m afraid that you’ve been running it on the ragged edge long enough that there are damaged MOSFETs in the amps and you are close to an imminent failure. 

I could be wrong, but every time resistance (impedance) in an electrical circuit the current load will double, its ohms law. The amplifiers when wired to 1/2 ohm are going to attempt to flow double the current used at 1 ohm. Sure there’s a change in impedance as the frequency changes but that will also technically be half of what is seen at 1 ohm. Trying to run double the current it’s designed for without  very stable voltage input (low voltage also increases current draw) is a recipe for disaster and equipment failure. Like I said, I could easily be wrong but the information suggests at least warranting a look at the amps themselves. At least for the protection issue, there’s also a slight possibility they were already damaged from when they were strapped.  Technically speaking if everything is designed and installed correctly the amps should never go into protection when running normally. 

That’s just my worthless .02 

Edited by altoncustomtech

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On 2/3/2018 at 11:40 PM, frogcase2002 said:
On 2/4/2018 at 1:07 PM, altoncustomtech said:

My other worry, as you also stated, is about the amplifiers seeming to not handle the loads like they used to.  

The SAE line was never designed to be as robust as the SAZ line in the first place. More of a budget friendly option while still very solidly built was the goal I believe. You’ve been running them below their minimum rated impedance and while you have some upgraded electrical I am not certain it’s enough to properly feed those under that kind of load. I’m afraid that you’ve been running it on the ragged edge long enough that there are damaged MOSFETs in the amps and you are close to an imminent failure. 

I could be wrong, but every time resistance (impedance) in an electrical circuit the current load will double, its ohms law. The amplifiers when wired to 1/2 ohm are going to attempt to flow double the current used at 1 ohm. Sure there’s a change in impedance as the frequency changes but that will also technically be half of what is seen at 1 ohm. Trying to run double the current it’s designed for without  very stable voltage input (low voltage also increases current draw) is a recipe for disaster and equipment failure. Like I said, I could easily be wrong but the information suggests at least warranting a look at the amps themselves. At least for the protection issue, there’s also a slight possibility they were already damaged from when they were strapped.  Technically speaking if everything is designed and installed correctly the amps should never go into protection when running normally. 

That’s just my worthless .02 

The enclosure design is about the most important thing in an audio setup especially trying to get higher numbers . So even if the enclosure is buit the best it possibly could if the design isnt good it will not do/sound good. The enclosure definitely is an issue as its not designed for the subs . . . . .  Have you been monitoring your voltage while bumping? Cause I bet pretty bad voltage drop is causing the amps to protect more than having them at .5 each. 

Sould be able to get at least in the mid 40s with what your running

 

I have Two meters I'm running, one on front battery and one on my audio system battery, the battery for audio isn't made for it technically but it's 1000cold cranking amps and 140 amp hour @ 1a battery. I'm getting 14.5 to 14.7 volts steady with minimal fluctuation .1volts max and that's normal listing with my mids amps and highs amps running as well at engine speed of 1800rpm so the alternator is consistent. That's at both batteries with mysteriously no changes between the two.  Same setup running and engine speed the same except now we are up in volume and front battery is at 14.6 volts with Fluctuations from 14.6 to 14.1 volts and rear dedicated battery is 14.5 to 14.1/14.0volts. My meters Iv calibrated with my snap on volt meter and it's been recently calibrated  by the dealer. I used my volt meter and graphing tool to layout a volt fluctuation over a 2 min run time for theses numbers. Ran unit for about 25 mins before hand to get Amp and battery's to normal conditions. I knew that the enclosure was important " in my opinion more so than the  equipment". It's oversized a little for power issues besides that it's a decent design other than my failure to think about port loading for my cab and placeing the port in the center. Thanks for the help 

On 2/3/2018 at 11:40 PM, frogcase2002 said:

The enclosure design is about the most important thing in an audio setup especially trying to get higher numbers . So even if the enclosure is buit the best it possibly could if the design isnt good it will not do/sound good. The enclosure definitely is an issue as its not designed for the subs . . . . .  Have you been monitoring your voltage while bumping? Cause I bet pretty bad voltage drop is causing the amps to protect more than having them at .5 each. 

Sould be able to get at least in the mid 40s with what your running

 

 

On 2/3/2018 at 11:45 PM, ManzKea said:

Yea I got a dual 12 set up hitting 143 in my jeep. Like frogcase said, design plays a huge factor. And 4 15s in a truck should be bumping. Is it a wall or blow through?

Well it's actually not either but almost a wall. It goes from roof to floor but sides and top are not sealed to truck yet since I'm having to work on it and stuff so it's more like a big box, picture a high end pro box except big center port and has 7 sheets of mdf in it lol

 

On 2/3/2018 at 11:50 PM, frogcase2002 said:

Also how much port area is there?

278.8 inches and im not exactly sure I got enough. I think I'm right in the bare min for my setup at 19mm xmax. If it's way off and time is abundant, please advise me from start to finish how to obtain the correct area and length for porting. I got common sense but putting it in terms that's reasonable would be awsome, first time I ever installed a speaker or did anything audio was only 9 or so months ago lol.

 

On 2/4/2018 at 1:07 PM, altoncustomtech said:

My other worry, as you also stated, is about the amplifiers seeming to not handle the loads like they used to.  

The SAE line was never designed to be as robust as the SAZ line in the first place. More of a budget friendly option while still very solidly built was the goal I believe. You’ve been running them below their minimum rated impedance and while you have some upgraded electrical I am not certain it’s enough to properly feed those under that kind of load. I’m afraid that you’ve been running it on the ragged edge long enough that there are damaged MOSFETs in the amps and you are close to an imminent failure. 

I could be wrong, but every time resistance (impedance) in an electrical circuit the current load will double, its ohms law. The amplifiers when wired to 1/2 ohm are going to attempt to flow double the current used at 1 ohm. Sure there’s a change in impedance as the frequency changes but that will also technically be half of what is seen at 1 ohm. Trying to run double the current it’s designed for without  very stable voltage input (low voltage also increases current draw) is a recipe for disaster and equipment failure. Like I said, I could easily be wrong but the information suggests at least warranting a look at the amps themselves. At least for the protection issue, there’s also a slight possibility they were already damaged from when they were strapped.  Technically speaking if everything is designed and installed correctly the amps should never go into protection when running normally. 

That’s just my worthless .02 

Thanks for the reply, I tottaly see what your are saying and that's could be the case. I just like to check all my rugs for dirt before I tell someone els to clean there's if you catch my drift.  Couple questions if you don't mind? I hear the fuss

about strapping, I have to ask why do they not prefer it? Simpler to do and more consistent and just looks better to me. They say it's bad on the amps but how? If one fails it doesn't necessary mean that the other will fail, but if your running let's say huge subs and huge air space and loads of power and your unstrapped and one amp goes out the other will still play and if you loose half the drives in a shared air space that's excessive in size and and was already approaching max excursion...."which I would believe is common for a amp to fail do to heavy loads" wouldn't the drives left in the enclosure still playing almost be certain to get damaged? Just a thought I had and would like better understanding. When I first got these Amps I had this issue and I was at 2 ohms a piece and that's why I believe it's not the Amps it's me. I'm running factory alternator but I have good grounding and I'm useing actual 0/2 cable that's welding cable for just about everything and just useing a addapter to neck down at Amps so it fits. Got one long run of 0/3 cable from engine block to battery to chassis and back to audio battery. It's way excess but I'm planing on something large very soon but that's another story!!! And I'm not saying 2 gauge or 3 gauge This wire is like 1.3 inch diameter and heavy as hell, real American stuff here 

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Hay guys I think I finally found the issue. I'm useing a separate eq that's my main control, so I was turning the low pass all the way open and useing my eq filter, well it's is about fried and I was getting burst or spikes of 500 hertz to the subs while playing. The filters can cause this issue correct? It's working good so far. Also anyone got anymore imput on the strapping vs not 

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