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Discussion Starter · #1 · (Edited)
ok guys, i need some honest answers and like no bs, if you don't know don't post b/c this is important.

I have the following items:

- 2x 15'' rockford fosgate 300watt max power/2.0'' voice coil/ 8 ohm subs/speakers idk
- 2600 watt pyramid amplifier w/ 2 channel bridgeable

The following questions need answering:

1) Can i hook these things together without blowing something? (if so please explain? maybe lowering the amp's power or w/e idk how this crap works)

2) Will these kick hard/decent or am i looking at a p.o.s. system?

If you need any more info please don't hesitate to ask, thanks!
 

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Life finds a way
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I'm not familiar with rockford's 15s that much but I would have to say that the pyramid amp would blow before the RFs do. Personally if I were you, sell or even throw away the pyramid amp and get a decent 600 Rockford 2-Channel amp. I got mine and a 10" MB Quart sub for like $140 on ebay and they have been working for the past three years with no problem, even if I crank the system up all the way, the sub keeps pounding and the amp never overheats even though I have it under my passenger seat in brother's Dakota (was mine when I did the install).

Lowering the amps on the amp? If you are talking about the fuse you are only talking about spending gobs of money on fuses because if you lower the amps on the fuse...you will blow them everytime you turn on the vehicle.

Idk though, RF makes some really decent subs and I had a 10" HE2 and that thing pounded like crazy, so for you to have two 15s, make sure to carry some pain medication for your headaches.

btw...could you post some pictures of the bottom of the subs? I would like to know what series they are, thanks.
 

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well a pyramid amp that says its 2600 watts is more likely to put out approx 200 watts max, not a very good amp .. in my opinion that is, i have worked for car audio companies doing installs and sales, so i have quite a bit of experience in this field, now with the subs, having 2 15" subs in the back of your car is going to take up ALOT of room, are you putting them in a truck? or hatch? personally i would sell everything you have, go with 1 12" or 10 " than can handle more juice, high end alpine, or matts sub ... and a 1 channel class d mono amp.. i am running a pheonex gold 800 watt mono amp that is runing at 1 ohm powering a 12" Dual voice coil sub and the last comp i entered i placed 2nd, and hit 152 DB and thats with a custom box built in the trunk, and it doesnt take up much room either... its better to pay a little more $$ up front and get good quality hardware and it will last way longer sound much better, cleaner, and tighter punches..

then again.. thats my opinion :)

:angel:
 

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I Am The Machine
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Well, the amp is way more than you'll ever need for those subs. In fact, without toning down the amp, you'll have a good chance of blowing them if you aren't careful.

Personally, I can't see why you'd get 2 HUGE sub's running such low power and taking up so much space in your trunk. I'm running 1 10" Sony 1100W sub on an amp that puts out wya less than that and it is WAY more than I ever need. I'd get something much smaller or your already small trunk will all but disappear. I think you'll end up regretting it later ;)

That said, you may like this system, and in a small car it WILL kick hard, but you can get the same kick with one better subwoofer instead and the same amp (although I'm not too familiar with Pyramid). So, what I would do when you're ready to roll and its all hooked up is turn the car radio all the way down, the bass level to exact middle (not down or up), and the gain on the amp completely down. From there, slowly turn up the car radio to a comfortable level. The gain on the amp may or may not completely turn off the subs, some are not fully adjustable and only go through a small range. From that comfortable level, slowly adjust the gain to where you like the sound, then turn it down a little bit and leave it there. You don't wanna risk blowing your subs when you blast the music. You should be OK, I just don't see why you'd be running such huge subs.

What kinda box, ported? Just please don't say bandpass....lol.
 

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Discussion Starter · #5 · (Edited)
so if i put the amp to min it wouldnt help?

and the box is vented yes.

buying new things is out of the question guys, i need to know if this will work or not w/o blowing and the problem is, the subs are 8 ohm each, does the amp matter in this area or not?

EDIT: is 2 ohm, 4ohm, or 8ohm stronger on subs?
 

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so if i put the amp to min it wouldnt help?

and the box is vented yes.

buying new things is out of the question guys, i need to know if this will work or not w/o blowing and the problem is, the subs are 8 ohm each, does the amp matter in this area or not?

EDIT: is 2 ohm, 4ohm, or 8ohm stronger on subs?
if your asking will it work.. yes it will .. your amp will not put out 2600 watts.. its a bull sh*t number that they got for power... if you run both subs bridged it will run at 4 ohms.. if you run them in series it will run at 16 ohms.. the lower you drop the resistance the more power you will draw from the amp.. my opinion is to run them bridged at 4 ohms, the amp will run smoothly and should not have any over heating problems at all.. most amps can run smoothly as low as 2 ohms, the reason that subs come in with different ohm ratings is for different wiring setups, running 4 subs or 1 sub, and configuring the amp to run at its peak performance without going overboard..

now once its all hooked up, phantom has the right idea on how to tune the system so that its not overpowering your mids and highs, so you can read that post on how to do that :)

EDIT -- what model is the amp and what model are the subs? i can draw up a wiriing diagram for what will work the best for you .. if you want..
 

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I Am The Machine
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^Thanks, wiring isn't my game so I wasn't sure how to help him there.

Also, as Pete mentioned, the less resistance, the more power your subs will be able to draw. Ohms are the resistance, the lower the number the better, as long as the amp can support it (which it should be perfectly stable at 2ohms, I'd assume).
 

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Don't ask me, I'm a sofa.
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^Thanks, wiring isn't my game so I wasn't sure how to help him there.

Also, as Pete mentioned, the less resistance, the more power your subs will be able to draw. Ohms are the resistance, the lower the number the better, as long as the amp can support it (which it should be perfectly stable at 2ohms, I'd assume).
You know what assumptions are the mother of.
This is not quite correct, electrically.

An amplifer will have a specification of "Output Impedance", which will be in ohms. The lower the load (speaker) resistance, DOWN TO the output impedance, the more power may be delivered.
An amp with an impedance of 4 ohms will not deliver any more power into a 2 ohm load, and you would run the risk of damaging the amp's output. Check.

However, a 2 ohm bridged load is exactly the same load on the amp as a 4 ohm load on each channel. (BTW, it is a myth that bridging will give you any more power than running both channels individually. Ohms Law prohibits it.)

Also, car audio has a standard impedance of 4 ohms, not the 8 used in domestic speakers.
So in either a bridged (or a parallel per channel) config, you will have a 2 ohm load, while in series you will have 8.
 

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Discussion Starter · #9 · (Edited)
if your asking will it work.. yes it will .. your amp will not put out 2600 watts.. its a bull sh*t number that they got for power... if you run both subs bridged it will run at 4 ohms.. if you run them in series it will run at 16 ohms.. the lower you drop the resistance the more power you will draw from the amp.. my opinion is to run them bridged at 4 ohms, the amp will run smoothly and should not have any over heating problems at all.. most amps can run smoothly as low as 2 ohms, the reason that subs come in with different ohm ratings is for different wiring setups, running 4 subs or 1 sub, and configuring the amp to run at its peak performance without going overboard..

now once its all hooked up, phantom has the right idea on how to tune the system so that its not overpowering your mids and highs, so you can read that post on how to do that :)

EDIT -- what model is the amp and what model are the subs? i can draw up a wiriing diagram for what will work the best for you .. if you want..
yeah a diagram would help.

the subs are RFZ2815 and the amp is a pyramid pb2600

You know what assumptions are the mother of.
This is not quite correct, electrically.

An amplifer will have a specification of "Output Impedance", which will be in ohms. The lower the load (speaker) resistance, DOWN TO the output impedance, the more power may be delivered.
An amp with an impedance of 4 ohms will not deliver any more power into a 2 ohm load, and you would run the risk of damaging the amp's output. Check.

However, a 2 ohm bridged load is exactly the same load on the amp as a 4 ohm load on each channel. (BTW, it is a myth that bridging will give you any more power than running both channels individually. Ohms Law prohibits it.)

Also, car audio has a standard impedance of 4 ohms, not the 8 used in domestic speakers.
So in either a bridged (or a parallel per channel) config, you will have a 2 ohm load, while in series you will have 8.
i got lost man, all i need to know if will the 8 ohm speakers bother the amp in any way dude im not planning on being an electrician. do i bridge em or not?
 

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HAHA LOL !! Don't know mate. Seems like aliens have taken over the forum !!

Sorrey I cant help you, but I dont know much about audio and would not really have subwoofer in my car. I personally think its worthless and pointless and just extra weight !

Good luck though!
 

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i got lost man, all i need to know if will the 8 ohm speakers bother the amp in any way dude im not planning on being an electrician. do i bridge em or not?
Well I don't own one and chances are fairly low that other owners in this forum do...
But find me the spec from your documentation for "output impedance" and I can tell you.

Are you sure the speakers are 8 ohm? Car speakers are usually 4.
 

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Discussion Starter · #14 ·
Well I don't own one and chances are fairly low that other owners in this forum do...
But find me the spec from your documentation for "output impedance" and I can tell you.

Are you sure the speakers are 8 ohm? Car speakers are usually 4.
it's a 300watt 15'' sub and it's 8 ohm yes, idk wtf output impedew/e is...
 

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check the specifications page in the manual...
 

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i checked the specs out, sorry for the delay in the response, yes.. you can bridge the speakers, thus it will run at 4 ohms which your amp will have no problems running :)
 
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