I have a Rockford Fosgate Prime R500 powering my Idmax 12 D4. It plays fine and sounds good while driving around town, but if I take a longer trip and play bass heavy music for more than about 30 minutes, the amp overheats and goes into protection mode.

More info:

Amp is rated:
320 Watts RMS x 1 @ 4-Ohms
500 Watts RMS x 1 @ 2-Ohms

Gains are set at about 1/3

Power wire is 4 gauge (legit) to a distribution block in the trunk, then a 2-3 foot run of cheap Lanzar 4 gauge which is probably really 6 or 8 gauge.

Ground wire is the Lanzar stuff grounded to the same spot as my other amp (Sony 500 watt rms).

The Sony amp is wired with the legit 4 gauge wire from the distribution block and has no problems.

Any ideas? Would upgrading my power and ground wires help? Could the amp be defective or is that just something you should expect when you buy a cheap amp?

 

4g is plenty for the amount of power you're running. I wouldn't hesitate to say its just a bad amp. Prime line is pretty bad.

I would say if your gains are set correctly, it's either a bad amp OR you're wired at an impedance that it doesn't handle. Positive you have it wired at 2ohms??

 

How is the signal getting to the amp? Line driver? Line out converter? My guess is that the 1/3 gain setting was set by ear and you are actually over driving the input, therefor asking the amp to produce more than the 500 watts, and the amp can only do that for a period of time before it has to shut down. Turn your amp gain down further and it will probably be just fine. I know, you are losing volume, but to gain that back, you have to upgrade to a larger amp or use a more efficient enclosure (ported or Infinite Baffle), assuming your box is sealed.

Or, you have your sub wired wrong and driving the impedance too low like Trunk Monkey said.

 

Ah okay, I guess I'll call Sonic/Rockford and inquire about a warranty claim. I'm fairly certain that it's wired at 2ohms. Since it's a dual 4ohm, I believe the only other option would be 8ohms and that definitely shouldn't stress the amp, right?

 

The signal is coming from my processor (Alpine PXE-H660) which I believe outputs at 4V. The sub is mounted infinite baffle. It's my understanding that a single dual-4ohm sub can't be wired at less than 2ohms (2ohm/8ohm)

 

Yeah I'd at least open a claim before its too late. If you find out it as user error then you don't need to send it back.

When you say overheating...do you mean physically? Or is it just going into protect?

 

I mean you could cook a steak on that thing

 

Ok. So, you are overdriving your amp into protection. I checked and your h660 does output 4 volts. You amp accepts up to 8 volts input, but you still may be over driving the input with your gain switch 1/3 the way up. You can technically over drive an amp with the gain switch all the way down if you have enough input voltage. Try turning the gain down to about 1/4 the way.

Also, if you are using the bass boost or remote gain knob, you are DEFINITELY over driving your amp.

 

Ahhh...didnt think about that. No remote bass knob hooked up? I would do what Jerry said and turn the gain down a little and see what happens. It shouldn't be getting that hot after 30 minutes with a good input voltage/low gain

 

Those things are not great amps. If it is not going into protect, then it is probably working as designed... it is just designed to be economy level. Heat kills electronics. Hot amps don't last long.

Try it at 8 ohms. I have no idea how the power supply and channels work on that amp, but it might be more than enough output for you. Some of the better RF amps put out nearly the same power at 8 ohms as they do at 4... but I don't know how the prime are built.

Are there any install restrictions on it that you might be violating? Does it have to be flat, or with a certain side mounted up? How do you have it mounted? What does the manual say about mounting?

 

Update:

Great news. Called Rockford tech support and the technician implied/unofficially confirmed that this particular amp sucks. He recommended that I call Sonic and request that they replace it with the Prime R500-1D which is the updated Class D model of this amp and would run a lot cooler.

I called Sonic customer service and the rep told me that they couldn't do a return since it had been more than 30 days and that if I did a warranty claim the best they could do is fix it or send me a refurbished one.

I went on a minor rant about how it had only been a month and a half since I bought it, that a refurbished amp would likely have the same issues, and how companies should go the extra mile to make the customer happy...blah blah blah

He finally agreed to speak to his supervisor and when he came back he said they did some checking and it turns out they have had numerous complaints and returns with this amp so they agreed to give me store credit - Whooohooo!

Alright, so now that I get a do over which amp would you guys suggest?

Again: (1) Idmax 12V3D4 - Infinite baffle, 4 gauge wire
Budget: 200ish ($130 in store credit + $75-$100 more if needed)

 

Oh dang....that's a class A/B amp?! Yeah....

Let me check out Sonic for that price and I'll give you my personal preference of amps

 

Sweet. Thanks!

Any opinions on:

PPI P1000.1 ($209/make an offer)
http://www.sonicelectronix.com/item_...r-P1000.1.html

Hifonics Brutus BRZ1200.1D/BRZ1700.1D ($179/$239)
http://www.sonicelectronix.com/item_...RZ1700.1D.html

Or any others that may be a little over that range, but worth the extra money.

Needs/preferences:
1. Infrasonic Filter
2. Runs cool (Texas summers are pretty brutal)
3. Resale value
4. 1ohm stable/ability to add another Dual 4ohm sub in the future

 

1. PPI p1000.1 - http://www.sonicelectronix.com/item_...r-P1000.1.html

I made a fake offer on this amp and was told it can be had for $188

1. PPI BK 1300.1 - http://www.sonicelectronix.com/item_...BK1300.1D.html

2. PPI BK650.1 - http://www.sonicelectronix.com/item_...-BK650.1D.html

3. Pioneer 8500D - http://www.sonicelectronix.com/item_...GM-D8500M.html

4. Kenwood 9105D - http://www.sonicelectronix.com/item_...KAC-9105D.html

That would be my list in order. The PPI Phantom seems to be a solid amp. The BK is supposedly based off the Soundstream Rubicon, but better. The Pioneer's 4-channel sister amp got a solid review from PASMAG. And I see that damn Kenwood amp plastered all over Craigslist all the time! I'm sure it's a decent amp for the price...


I wouldn't go with anything Maxxsonics makes (Hifonics, MB Quart, etc). They just aren't the same as they used to be

 

AB does not have to be hot. Price-point and smaller footprint have driven a lot of them that way.

I would just get the D that the are replacing it with. All of those above are probably about the same. I would appropriately set your expectations of the lifespan of an amp in this category if run at one ohm for long - even though they might be stable, I would be shocked if the heat did not make for a short life.

If you get another sub, I would run them at 4 ohms. A solid A/B channel bridged to put out 600-1000w are available, cheap and usually reliable. I would look for old school 2 channel like MTX 2300, PPI a600 (old one) or Fosgate 800a2 will all bench out at over 800 real watts (1000 or so on the Fosgate) and are about $150-175 used (even being 10 years old).

 

Looks like the P1000.1 has everything I'm looking for. Thanks for the info! Especially the make an offer price.

That's a good point about running two D4's on a 4ohm load vs 1ohm. I'd rather not stress the amp if possible. I don't think I'll be adding another sub anytime soon anyway. The one Idmax is more than enough for now. I was mainly looking at 1ohm stable amps because I figure if they can handle 1ohm then they should do 2ohms without breaking a sweat.

I'm all about buying used gear, but this time I'm limited to what Sonic has in stock. I'd consider a two-channel, but it would have to be able to do 2ohms bridged since right now I just have the one D4.

 

Let me first say that I have no idea how much this actually matters, but the one you have now has 2 30A fuses...the one they want to replace it with it 2x25A lol. Not a huge deal, but when their top of the line T500-1 has 100A worth of fuse, that would make me a little leery.

He needs to buy new from Sonic also, so old/used amps are out of the question. Plus...some of them need external crossovers. Can't remember if you're running one, but still..you get my point. Some of those older amps were very nice though! I had a a600.2 at one point back in the day

If you wanted to stay with Rockford you could look at their Punch line, but it's still $300 for an amp that puts out 400@2ohm. Completely up to you though

 

Nope. I only bought the Rockford because it was cheap.

 

I dunno...the PPI phantom line is pretty stout for the price. Small and supposedly don't get hot at all. Plenty of power/headroom.

 

Yep. I think that's what I'll get.

 

Ordered the PPI BK1300.1D for $189

http://www.sonicelectronix.com/item_...%5BIgnore%5D=1

Hopefully should have no problem pushing the Idmax now

 

Should be plenty for IB. Probably right around 550 @ 2ohms @ 12-13v if it's rated like the Phantoms, which I would assume it would be..

 

Just modeled it. 500w to a single 12" Max infinite baffle will push it to xmax as long as you have a subsonic filter at 20hz. If not you will be a little past xmax.

On the flip side, 1,000w in the factory recommended enclosure will be 4mm shy of xmax. It will actually be louder in the lower frequencies off of 500w in IB than 1,000 sealed.

 

Awesome. I was actually going to ask you if you could model it for me because i was curious how much power I could feed it before reaching xmax. I've been running it off of a 1000 watt alpine for the last couple days while I wait for my new amp to get here and it sounds incredible.

I'm really loving the IB setup. With the parametric EQ and subsonic filter I can make it sound any way I want it. It can go from low end monster to SPL fart box to completely flat and everything in between with a few button clicks.

 

I fully agree with your opinion. That's the beauty of IB, you start out flatter so it's so easy to shape the sound to your liking and you don't have to worry about running out of power for the low end. Looking forward to your results. I've seen great reveiews with the IDMax IB.

 

Once I move into a house in a few months and have a garage, I'll likely switch to IB and give it a try.

 

Do it! I'd like to hear your opinion on how it compares after trying both setups.

 

Picked up some new components! I'm not ready for the Dyns yet, but I got a sweet deal on some ID XS-65's from Niebur3 at High Definition Mobile Audio. Thanks Jerry!