Question about Amps and Subs

MudslinginXJ

NAXJA Forum User
Location
Pennsylvania
I was recently looking around for some amps and subs. I have a Pioneer DEH-P5500MP head unit and 4 Infinity Reference 5002i 5 1/4" speakers. I found a kit at circuit city that comes with 2 Sony 10" subs at 300watts a piece and a Sony 480Watt Amp but its 2 channel. I take it that it will only power A pair of speakers or the subs correct? Would i need a 6 channel amp to run 4 speakers and 2 subs? I'm not really familiar with all this so im trying to catch on as quick as i can. If you have any preferences as to what are some good, well priced subs and amps i'd greatly appreciate it.

Im not worried about a box right now because when i get some subs and an amp i'll be making a custom box. Any idea's for that or some tips to help me in the making of a cool custom box i'd appreciate that too.
 
For money saving purposes, get a four channel amp, bridge the rear channels for the sub and use the front channels to power your front doors. Run the rear hatch speakers off the deck power. I would strongly consider one 10" or one 12" max. I have one 12" in less than a cubic foot of space and it sits out of the way. I listen to every type of music and it is just right.(and I can make it more than loud) I have a two channel going to the front 6.5" speakers and a mono sub amp on the 12" dual voice coil sub. I'm putting alot of power to good speakers. Save up and get good speakers and a decent amp you will be blown away at what you can do. Hit me up if you have more questions.
 
I run factory door speakers and a set of tweeters for the front and in the hatch I have 6x9's then for subs I have 2 orion 12's in a sealed box. I run the doors and hatch off the head unit and my subs have an amp bridged to them. It screams and the bass is really loud. My head unit has a digital processor which allows me to control all the speakers easily. I just shut the bass off to all the speakers except the subs. I have no disortion. As for an idea for a box I have a picture where someone made a plexiglass tire for a box. HTH DuG
 
You might want to consider running two amps. One four channel for the speakers and a second one for the subs. I like power accoustik amps, because they are resonably priced, and I haven't had any problems with mine yet. As for how many watts, I'm not sure. I dont know how many watt your speakers can handle. I have always been told that it is better to overpower speaker rather than underpower them. Oh yeah, I like rockford fosgate's subs. I have a pair of 12's and they suit my need well. That is all I can think of right now, hope this helps a little. Later.
 
SeattleXJ said:
For money saving purposes, get a four channel amp, bridge the rear channels for the sub and use the front channels to power your front doors. Run the rear hatch speakers off the deck power. I would strongly consider one 10" or one 12" max. I have one 12" in less than a cubic foot of space and it sits out of the way. I listen to every type of music and it is just right.(and I can make it more than loud) I have a two channel going to the front 6.5" speakers and a mono sub amp on the 12" dual voice coil sub. I'm putting alot of power to good speakers. Save up and get good speakers and a decent amp you will be blown away at what you can do. Hit me up if you have more questions.

What Speakers do you like? I've got a 98 XJ with 6 1/4's front and rear
Looking to buy Deck, 4 channel Amp and Posibly Infinety Cappas, or ?
Thanks up Front
 
The recomended Amp Wattage range for my speakers are 2-45. The Peak power handling watts is 135. Joe Cool What would you suggest for the amp watts. The Power Acoustics are pretty reasonable. Should i get the Power Acoustic A600-4HP for the 4 speakers and get the Power Acoustik Gothic OV4-800 [font=Arial,Helvetica]for the subs or get the Power Acoustik LT960/4 for the subs? Thanks for everyones help so far.
[/font]
 
Cruzzin_XJ said:
What Speakers do you like? I've got a 98 XJ with 6 1/4's front and rear
Looking to buy Deck, 4 channel Amp and Posibly Infinety Cappas, or ?
Thanks up Front
If your talkin about speakers i really like the Infinity Reference 5002i's but if your talkin subwoofers im going to go with the Rockford Fosgate Punch stage 1 2 pack. They are 10" 4 ohms and for a set its onsale for 99.95 at cardomain.com Although i will probably buy them as well as my other stuff from TheZeb.com
 
Amps, speakers... my thoughts

:compwork: Well, I've done it all really. Cheap amp, good speakers... cheap speakers, good amp... good amp, good speakers. REALLY good speakers, great amp. Honestly, their are alot of decent amps. If you install it properly most will perform close to what they advertise. My personal opinion is to spend more on nicer speakers and get a quality but not too spendy amp. Everyone has a different price in mind. I LOVE LOVE LOVE Image Dynamics subs. :worship: Specifically the IDQ series but the entry level model is nice too. I've done a system in my girlfriends car and 3 friends cars all using ID subs. I did a Rockford Fosgate 4 channel in her car, 75x4, front two to the doors and rear bridged to the IDQ10. Very nice system.

I currently run MB Quart 7" coax format up front (I say format because they are a separates set and I mounted the tweeter over the driver. ) They are the old QM series, which was one model below the best they made back then and they smoke most of the crap that MB Quart makes now. They are getting ~150 watts each via a 2 channel Rockford Fosgate amp. My rear hatch speakers are basic 5.25" JBL running off the Alpine deck. My sub is an Image Dynamics IDQ12 with a dual 4 ohm voice coil. It's powered by a Rockford Fosgate 1000BD mono amp that I've measured to push ~1148 watts @ 2 ohms. Over kill on the power there but its throttled back and the sub loves the match. Very dynamic and musical, tight and I can boom the crap out of it with a turn of the "throttle" (remote gain). I have 2 one farad capacitors and an Odyssey 1700 dry cell (better than 2 optimas)

I'm not sure about the new amps Rockford Fosgate is putting out but I've had great success in the past with them. Can be spendy but shop around. Last years amps (good) may be cheap to pick up. I suggest ~50-75 watts per channel depending on your front speakers handling. (you can usually exceed the RMS by 10-20 watts and be fine) and maybe something that you can bridge the rear channels together.... to power one 10" or 12". Don't skip on the wattage, it really matters.

RF also makes decent subs although I dislike the plastic crap on the new subs. Downside to a Image Dynamics sub is it needs probably 200-300 watts for a 10" to do well. so maybe a mono amp for the sub only is in order. Shop around and ask around. In the end it's your budget that will dictate what you buy. Again, good speakers, decent amp with enough power. It really makes a difference. Consider a capacitor if you are going over 300 watts total.... 4ga wire minimum, check ebay and make sure you know what you are buying. Ask if you aren't sure. I’m all ears. Now at least. *PHEW*
:soapbox:
 
Cruzzin_XJ said:
What Speakers do you like? I've got a 98 XJ with 6 1/4's front and rear
Looking to buy Deck, 4 channel Amp and Posibly Infinety Cappas, or ?
Thanks up Front

Image Dynamics for the subs and they have a CTX series for the coax that is better that most entry-mid level coax sets out there.

I love MB Quart, a little bright but you can adjust that. I'm not happy with the direction of the new entry level lines.... (downhill on quality in everything below the very top end models). Honestly I'm probably going to step up and go with Image Dynamics Chameleon Series or Focal for my next project's front speakers and an IDQ sub. Both are a little spendy but well worth it.

I really have faith in Eclipse decks (I have one that I moved to my girlfriends car that is 8 years old and still SOLID). I currently own a very nice Alpine because of the great price I got on it but I will buy another Eclipse when it comes time.

Rock on. :music:
 
joecool said:
I have always been told that it is better to overpower speaker rather than underpower them.
There's a limit with this thinking.

True, under-powering a sub will destroy it, but having more power on hand than the speaker is rated for will, in time, catch you.

Death from underpowering is not pretty - but you'll hear the "noise" coming through in time to save things.

Death from over-powering is rather quick - POP, fizzle, maybe a small puff of smoke if you REALLY did a number on it - either way, the result is the same - dead voice-coil.

A good rule of thumb for everyday systems is to stick close in power to the RMS ratings for the speakers - you can stick close to the MAX rating (which is the larger of the two numbers when speakers are rated - and still be fine if you're careful with the volume, bass-boost, LOUDNESS, etc.

Here's an example of the rating differences:

This info is for a
Polk Audio GNX124
12" 4-ohm Component Subwoofer
Key Features:
  • poly-mica woofer cone
  • MOMO-designed steel basket
  • 2" voice coil
  • power range: 50-175 watts RMS each
  • peak power: 400 watts
  • frequency response: 18-400 Hz
  • sensitivity: 93 dB
  • top mount depth: 5-13/16"
  • sealed box volume: 1.25 cu. ft.

So what we're seeing here is the RMS power is the actual power the amp is putting out continuously. the definition of RMS is as follows:
RMS
Root Mean Square is a formula that provides a reasonably accurate means of measuring and comparing continuous AC power. The use of this measure is preferred when matching system components, like amplifiers and recievers.


The MAX power is like a spike in power - many amps nowadays can run all day at MAX power, so that, in effect, becomes their average output. Here's the definition:

Peak Power Handling (MAX)[font=Times New Roman, Times, serif]
Peak power handling refers to the amount of power a speaker is estimated to handle during a brief high-intensity musical burst. Since this can vary with both frequency and amplitude, it is a much less accurate way to judge speaker durability and performance than RMS
[/font]

The downside to that high power is big current draw and excessive heat - which will kill the amp eventually (unless maybe it's one of the original Punch 45's from RF - I mounted one under my dash, wired it for 1 ohm and after 2 weeks in the summer opened it up to find 2 diodes melted out of the soldering on the IC board and fused to the heat-sink (remember, it was upside down). The unti worked flawlessly - that was quality. Too bad they don't make them like that any more... :( )

Anyway, the long and short of it is match your RMS powers between the speakers and amps and you'll be happy all day long.

Can you tell I used to install car audio for a living...LOL
Oh yeah - pay attention to the power requirements of the amp and use a good installation & power kit for it. It makes a difference.


 
Wow thats a lot of information :twak:

Ok so Heres what i got in mind...tell me what you think.

i already have the head unit and the hatch speakers.

Head Unit: Pioneer DEH-P5500MP

Speakers(front & hatch): Infinity Reference 5002i RMS: 2-45W PPH: 135W (willing to buy different front speakers if there are better ones.

Subwoofers: Rockford Fosgate P110S4 10" at 4ohms RMS:150W PPH 300W

Amp #1: Power Acoustik PS4-240 35x4 at 4ohms 180W RMS Total (how does this sound for the front and rear speakers? Do you think its enough power or should i go with lets say 70x4 at 4 homs 340W RMS)

Amp #2 Not sure if i should get a 4 channel or a 2 channel? Uhm...can someone point me in the right direction here?:huh:

Also do you think i'll need to run a capacitor?...if so anyone one have any suggestions?
 
it looks like you have good speakers and the head unit from my experience is pretty good, so why go with a cheap amp. I have not had good luck with Power Acoustiks stuff. You might want to ocnsider running a four channel amp for your mid range and get a single or dual channel (that can be bridged) for the Sub. Its not the Power its the quality that makes you groove. As long as the enclosure is built right (depends on the music of choice and vehicle specs) you can get away with 100 watt amp. If you stay low a .5 Farad cap will do just fine for the sub amp.
 
algeroth79 said:
it looks like you have good speakers and the head unit from my experience is pretty good, so why go with a cheap amp. I have not had good luck with Power Acoustiks stuff. You might want to ocnsider running a four channel amp for your mid range and get a single or dual channel (that can be bridged) for the Sub. Its not the Power its the quality that makes you groove. As long as the enclosure is built right (depends on the music of choice and vehicle specs) you can get away with 100 watt amp. If you stay low a .5 Farad cap will do just fine for the sub amp.
Uh-huh.

Stick with the gear you have - Infinity Ref is solid - the Pioneer is good too.

I agree with buying a quality amp to drive the subs.

No need to go too crazy - just wire the subs together for a 2 ohm load, get an amp which is stable at 2 ohms and puts out around 300 watts WHEN BRIDGED MAX.

As for the cap - we were running a heck of a lot more power than what you propose back in the day before caps were a big deal. I personally would skip the cap, but I personally don't mind my lights dimming a smidge when I pimp...:listenmus

Just make sure you buy GOOD QUALITY amp install kits - I can't stress this enough. Too many folks buy good gear and run power to a 500 WATT amp through 12 ga. wire - OUCH!

Here's some tips:

How To Choose The Right Wiring
Harness/Kit For Your System
[font=Times New Roman, Times, serif]
[/font][font=Times New Roman, Times, serif][font=Arial, Helvetica, sans-serif]Look at your amplifier's fuse. It should be at or below the rating for the wiring you are considering. So, if your amplifier's fuse is say, 25 A, then you can use wiring rated at 25 amps or above. Never use wiring smaller than the fuse rating (greater is OK). The fuse rating is your key to the correct wiring package for your installation. NOTE: Some kits are for wiring the power/ground/remote only, while others include wiring for the signal (audio output) as well. Check the descriptions carefully to be sure you choose the correct kit for your needs.[/font][/font]

I will be running 6 gauge wire to the rear of my Cherokee next month (allows me to use a 60 AMP fuse to run multiple amps). That wire goes into the fuse holder/distribution block. This in turn allows me to wire up multiple amps to one power source located in the rear of the truck - just the thing to keep the wiring simple.

...oh yeah, don't forget to run the rca cables and power lines down opposite sides of the interior...
 
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Ok so everything i listed checks out ok right? Except for the Amps and stuff. About the Amps, most of this stuff is still greek to me and im trying to catch on as fast as i can so i was wondering if someone could tell me what amps i should buy and what Amp install kit that way i wont hurt anything.
 
What amp to buy and what kit to buy...well, ultimately, you'll need to decide how many greenbacks you're willing to part with there.

Sticking with brand names is always a solid choice - Rockford, Alpine, Pioneer, Kenwood, Sony, etc. all offer decent gear - BUT, not in their entry level lines. Rockford dumbed down the Punch series...not so good any more (I'm not saying it's not good, just that originally it was better gear with the same name).

Sony offers the Xplode series - junk (ask me how I know...:soapbox: ). Pioneer, Kenwood, etc all have the same issues in their entry level gear.

Basically it comes down to this - what's the budget, but the best possible product for the money. Don't fall for the 10,000,000 WATTS RMS with 0% THD form 20 - 20K crap. Look at your speaker's needs, watch the power consumtion (amps drawn at peak) and go forward form there.

None of this means that lower priced unit won't perform well. Try, if al all possible, to listen to the amp run a speakers of the SAME SIZE you're going to put the amp on. If you have 2-ways, audition the amp on 2-ways - that kind of thing. In the end it'll still sound different when installed - cause your Jeep is not the sound-board at the shop...LOL

If you're gonna push me, go for something like this amp:

Tuner-inspired cosmetics and hard-hitting power define the Octane-R series amplifiers from Phoenix Gold. Sure, they look good, but these amps back it up with dynamic sound control and plenty of muscle to drive your speakers!



Don't mess around with your sound! Install the Octane-R 5.0:4 amplifier in your vehicle, and be sure that all of your speakers are getting the power they need to sound their best. With 50 watts RMS driving each of the four channels, you'll enjoy clean, clear sound at all volume levels.

Phoenix Gold Octane-R 5.0:4 - from Crutchfield


50W x 4 car amplifier


special-sm.gif

FREE Digital Voltage Display — a $59.99 value!
buyfromcrutchfield.gif
Item #218OCR504In Stock Our Price - $249.99
Bridge the amp to 2-channel operation, and power up a pair of subs with 150 watts RMS each. Read more


Key Features:
  • 50 watts RMS x 4 at 4 ohms
  • 75 watts RMS x 4 at 2 ohms
  • 150 watts RMS x 2 at 4 ohms
  • variable high- and low-pass filters (40-400 Hz at 12 dB/octave)
  • variable Twin "T" bass EQ boost (0-15 dB boost at 45 Hz)
  • blue LED logo illumination and optional blue neon attachments
  • preamp inputs
  • preamp outputs
  • requires 8-gauge power and ground leads — wiring and hardware not included with amplifier
  • two 25-amp fuses
  • 15-15/16"W x 2-9/16"H x 10-13/16"D
  • warranty: 1 year
As for install kits, something like this should be plenty:



[font=Times New Roman, Times, serif][font=Times New Roman, Times, serif]Model #POWERKIT3[/font] Power Accessories 6 Gauge Amplifier Power & Signal Wiring Kit With RCA Interconnect
[/font][font=Times New Roman, Times, serif]* 20-foot 6-gauge translucent red power wire
* 4-foot 6-gauge translucent blue/purple ground wire
* 20-foot blue remote turn-on wire
* 25-foot RCA interconnect cable
* 25-foot speaker wire
* Water resistant fuse holder
* 60-amp AGU fuse
* 6-foot split loom


* Complete with connectors & wire ties
[/font]
[font=Times New Roman, Times, serif]

Price $39.95
[/font]




powerkit3.GIF


Now - this is not the be-all-to-end-all gear here. The choices are yours. I'd be happy with this gear in my Heep, though. if you have money quid the throw at it, you may weant to look at the RF Power line-up of amps - that line is basically what the original Punch line used to be.

HTH

BTW, my personal fav amps are Nakamichi or HiFonics if you can fine them and have the money - sweet, sweet sounds!
 
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Im willing to spend some money for good sound. I just dont want to spend to much. I'm willing to spend $500-$600 on the system with everything i need. Also about sub boxes. What is my best bet for a box? Also should i get 2 of those Phenoix gold octane-r ? and bridge the one to power a pair of subs? One more question. If i was to get different subs since you said the punch line is junk compared to the good ol' days should i get 2ohm or 4ohm subs?
 
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First off - I'm not telling you you should get any of the things I suggested - just that I'd be happy with them. :D

...though I was in that biz for quite a while, a number of years ago, I'm certainly not the ultimate authority or anything. :lecture:

If you like the sound of something, you can decide it's worth your bucks.

Now onto your questions:

What is my best bet for a box?:anon:

Well, if you're handy with a saw, make your own using at least 3/4" MDF and good carpenters glue - if you keep all the cuts straight, it'll seal perfectly with the glue. After that, you need to know what kind of music you listen to - jazz, you'll want something that keeps tension on the sub and helps produce crisp, clear bass - of course, you give up boom here.

If you want boom, a ported box (designs vary) is the route to take - they give a big increase in boom (all things being equal), but at the expense of clarity and control - the bass won't be as "tight". If you're making your own, I hope you're good, cause these can get complicated...

It's up to you what you want, so again, listen to the same size (and preferably same power rated) sub in different types of boxes. The actual difference between the two ends of the spectrum may be close enough for you that you'll be happy with either. I'm personally a sealed box guy - I like my bass tight - then again, I like to listen to dance music, too - that's why we have a BASS control! LOL (Not LOUDNESS - ohhhh I hate that thing!!!:soapbox: )

Also should i get 2 of those Phenoix gold octane-r ? and bridge the one to power a pair of subs?

Well, if you go with an amp kit like the one above, you'll have the power covered, so it's your call. I'm a 4-channel guy and I like this set up:

Channels A & B run my fronts (at 4 ohms or 2 ohms depending on whether they are 2-ways or components)
Channels C & D are bridged to run my sub (I have one 12")
Rear fill is handled by my deck power - this allows me to "force" the sound-stage to the front of the truck by turning up the gain on the amp in relation to the head-unit. Basically, the amp is allowing more output in relation to the headunit. Or, I can simply fade the headunit to the front a bit. Since the rear speakers are the only thing using the deck power, they are effectively limited in their volume - and the soundstage stays up front.

What's nice about this setup is it allows me to run only one amp - less overall draw of current, less space needed by my sound gear and less chances of f-ing thing up during the install. Downside is the amps cost more - though with your budget you should still be able to find a decent one. (This idea will work with w bridgable 2-channel amp as well.)

Keep in mind that even amps rated as "low powered" by a lot of car audio guys will surprise you. Ever look at what the highend car audio gear in Lexus, etc puts out? It's usually nowhere near the 1000 + watts most folks want from their systems.

I'm perfectly happy with 25 clean WATTS per channel RMS - I won't be the loudest at the DB Drag, but that's not what I'm after. That kind of power is plenty for your main speakers - you'll go just as deaf with them cranked as you would with 200 WATTS a speaker cranked.:music:

For the sub, though, a bit more is in order, as it's the power that controls the in & out of the speaker's cone. Not enough and it'll over-work itself frying the voice-coil. Too much and POP! Just enough will allow you to tune the bass to match the output of the rest of the system ensuring you the whole thing is a joy to listen too...and can still bump when you're pimpin'!:jester:

If i was to get different subs since you said the punch line is junk compared to the good ol' days should i get 2ohm or 4ohm subs?


To be clear, I was refering to their amps (sorry, I should have been clearer on that point). The speakers are pretty much the same speakers as other manufacturers use. Basically there is one guy in Thailand who makes 75% of all the speakers on the market today - I exaggerate, but you get the idea.

As for 2 ohm or 4 ohm, check the amp - if it's 2 ohm stable and you can keep it cool, go for 2 x 4 ohms wired to net a 2 ohm load - bumps up the output nicely for you. If cooling is a concern, or the amp has 300+ WATTS RMS when bridged at 4ohms, grab 2 x 8 ohm subs and wire them up for a 4 ohm load - or grab 2 x 2ohm subs and wire them up for the same 4 ohm load - your choice on that one.

Just remember these two things:

Listen BEFORE you buy.
Boom responsibly.

Hope all this is helpful, bro.
 
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I feel like i learned something :) Thanks alot man. For now im all out of questions but im sure as soon as i start buying and installing the stuff i'll have more :p

Thanks once again.
 
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