Picking out Amp to match Subwoofers

[PHOENIX]

Can someone help me pick out an amp to run these 2 subwoofers I am about to buy?

JL Audio 8" 8W1-4

• 8" 4-ohm subwoofer
• polypropylene cone with foam surround
• power range: 35-100 watts RMS
• peak power handling: 200 watts
• frequency response: 28-250 Hz
• sensitivity: 86 dB
• top-mount depth: 3-3/4"
• sealed box volume: 0.3 cubic feet
• ported box volume: 0.75 cubic feet
• warranty: 1 year

I am getting 2 and they will be in a sealed box. I would prefer the Amp to be matching....meaning JL. And I don't want to over do it or anything so cheap is good for me I planned on buying these subs tomorrow off crutchfield.com so if you find one on cruthfield, I would appreciate it.

I have no plans for competitions or anything like that, just want a good bass sound.

- Dave

[jigtrix]

Hello,
I went to Cruthfield and it lacks selection for small amplifiers. If you want to stick with JL amps, the G1300 is a candidate.
JL Audio G Series G1300 Mono full-range amplifier — 300 watts RMS x 1 at 2 ohms at Crutchfield.com

If you want a more flexible amp, the alpine is not too bad. You can run your woofers and maybe a nice component set on your doors since is a 4 channel.
Alpine MRP-F300 V-Power Series 4-channel car amplifier 50 watts RMS x 4 at Crutchfield.com

Or a Pioneer thats also a 4X channel amp and very flexible to run front /rear speakers or bridge it for the subs only.
Pioneer GM-6400F 4-channel car amplifier — 60 watts RMS x 4 at Crutchfield.com

[o6spdracer]

^^definitely knows his stuff when it comes to audio.

If you are looking elsewhere (besides Crutchfield, who does not have a very good selection of JL Amps), you might want to also consider these. Richard, tell me if you have any other suggestions:
1. JL Audio 300/4V2, this is one of the new V2 series from JL
2. JL Audio 300/2
3. JL Audio G2250
I would go on ebay. They often have good deals. Good luck with your search!

[PHOENIX]

Thanks guys.

So....#3 that you picked out, the JL one on ebay....looks like a decent price. I am quite new to this stuff so excuse me if I ask a dumb question.... (questions pertaining to the speakers above, and the JL G2250)

1. Now I want the RMS on the speakers to match the RMS on the amp right? So at 4ohms on the amp, the G2250 is 60 watts.....and thats in the RMS range on the Amp. Am I getting this correctly? I don't want to go over 100 watts on the speaker cause I could damage it right? And If I go below 35 watts, it might not push it right?

well....I guess thats my only question, which is more than one question....but whatever


# New JL Audio G2250 Two Channel Car Amplifier
# Class A/B G-Series Two Channel
# Power rating

* 60 watts x 2 Ch @ 4 Ohms
* 90 watts x 2 Ch @ 2 Ohms
* Bridged 180 Watts x 1 Ch @ 4 Ohms

# MOSFET Power supply
# Remote bass level port ( RBC-1 Available for purchase separately)
# LED power indicators
# Bridgeable Two channel operation
# Protection Circuitry with Indicator L.E.D Lights
# Advanced Roll back protection Mode
# Differential Balanced input
# Speaker-level inputs
# Preamp RCA inputs/ outputs
# Absolute Symmetry Technology Class A/B Circuit
# Heavy duty aluminum alloy heat sink
# RCA level inputs
# Screw terminals
# Variable high-pass filter (50-200 Hz, 12 dB/octave)
# Variable low-pass filter (50-200 Hz, 12 dB/octave)
# Frequency response: 10-25,000 Hz
# Dimensions: 9-3/4"L x 9-1/4"W x 2-1/2"H
# 1 Year Streetstereo Warranty

[jigtrix]

The JL G2250 amp is even a better choice of amps I had listed above. I assumed that you wanted to purchase the amp @ Crutchfield. But since you are shopping Ebay, then you have a ton of choice. If you want to stick with the JL brand name, the JL G2250 specs recomended by 06spdracer is even better than the amps I had listed. You can run the amp @ 2 ohms and get 90 watts or bridged 180 watts @ 4 ohms. Parallel the speaker wires in order to run @ 2ohms. Here is a link that explain it in a diagram:
Parallel Series Speaker Wiring Diagrams - Car Audio .Biggz.com

1. Now I want the RMS on the speakers to match the RMS on the amp right? So at 4ohms on the amp, the G2250 is 60 watts.....and thats in the RMS range on the Amp. Am I getting this correctly? "Yes", but I would run at 2 ohms and get 90 watts. The woofer will hit harder.

I don't want to go over 100 watts on the speaker cause I could damage it right? "Yes, but it depends. Distortion is what kills your speakers. If it doesn't sound good, turn it down".

And If I go below 35 watts, it might not push it right? It will still push it. But it will not be loud and clean. It will be loud and distorted.

Originally Posted by PHOENIX

Thanks guys.

So....#3 that you picked out, the JL one on ebay....looks like a decent price. I am quite new to this stuff so excuse me if I ask a dumb question.... (questions pertaining to the speakers above, and the JL G2250)



well....I guess thats my only question, which is more than one question....but whatever


# New JL Audio G2250 Two Channel Car Amplifier
# Class A/B G-Series Two Channel
# Power rating

* 60 watts x 2 Ch @ 4 Ohms
* 90 watts x 2 Ch @ 2 Ohms
* Bridged 180 Watts x 1 Ch @ 4 Ohms

# MOSFET Power supply
# Remote bass level port ( RBC-1 Available for purchase separately)
# LED power indicators
# Bridgeable Two channel operation
# Protection Circuitry with Indicator L.E.D Lights
# Advanced Roll back protection Mode
# Differential Balanced input
# Speaker-level inputs
# Preamp RCA inputs/ outputs
# Absolute Symmetry Technology Class A/B Circuit
# Heavy duty aluminum alloy heat sink
# RCA level inputs
# Screw terminals
# Variable high-pass filter (50-200 Hz, 12 dB/octave)
# Variable low-pass filter (50-200 Hz, 12 dB/octave)
# Frequency response: 10-25,000 Hz
# Dimensions: 9-3/4"L x 9-1/4"W x 2-1/2"H
# 1 Year Streetstereo Warranty

[PHOENIX]

Thanks guys, i will be ordering tonight!

Question for you though, don't I want the ohms to match? You mentioned you would have the amp set for 2 ohms so it would have 90 watts and hit harder. Does the ohms matter?

[jigtrix]

Yes, Ohms matter and its a bit confusing to understand this. What are ohms, anyway?
Short answer: The ohm is the unit of measure for impedance, which is the property of a speaker that restricts the flow of electrical current through it. Typical speakers have impedance ratings of 4 ohms, 8 ohms or 16 ohms. The impedance of a speaker is a physical property that (ideally) does not change value, although in reality it does change somewhat with frequency. For this reason, the rating of a speaker is called its 'nominal' value, which pretty much means "in name only". For the purposes of this discussion, we will use the nominal value of the speaker's impedance.

Why are ohms important?
Two reasons:
(1) If you connect too many speakers to your amplifier, you risk blowing it up. You'll see why in the following explanation.
(2) Especially with tube amplifiers, but true in all amps, the amplifier will deliver maximum power (volume) to the speaker when the speaker impedance matches the internal impedance (called the OUTPUT IMPEDANCE) of the amplifier. If the speaker impedance is lower than the amplifier impedance, the amplifier will tend to overheat and more power is used up in the amplifier than is delivered to the speaker. If the speaker impedance is higher than that of the amplifier, its power output will be less than it is capable of. Impedance mismatches can also result in poor tone quality of the sound.

When you install your pair of 4 ohms speakers, then you got to connect the speakers in parallel to reduce impedance. Connect all speaker positives to positive terminal on amplifier. Repeat with negative connections. If all speakers have the same impedance, the total impedance is the impedance of a single speaker divided by the total number of speakers. Two 4 ohm speakers in a parallel connection will have a impedance of 2 ohms. Study the diagram that I attached here. The amp will see 2ohms resistance when you "parallel" wire them together.

Originally Posted by PHOENIX

Thanks guys, i will be ordering tonight!

Question for you though, don't I want the ohms to match? You mentioned you would have the amp set for 2 ohms so it would have 90 watts and hit harder. Does the ohms matter?

[kennyboi9o9of88]

I'm not a genius with the stereo setup, but this is my current setup. JL Audio component VR600 for the fronts and Polk Audio DB351 in the rears. I set up a JL Audio 300/4 amp, not the V2, but the original and I gotta say it sounds pretty damn good. Its putting out 75 rms all around at 4 ohms each speaker. I was considering wiring the rears through the headunit like how it was before so I can setup 2 subwoofers. I was looking at JL Audio 8w1 and plan to wire up the subs to the rear of the amp. My friend tells me 75 is good, but don't expect a lot out of it. I was also considering putting a single 10w3 and bridging to give me 150 RMS to the 10w3 and that should definitely give it some power. If you plan on getting new front speakers, I would say go with a multichannel amp. If you want to get new rear and front plus a sub, I'd say go with a 5 channel amp, but again, dont expect that much power.

I would go with JL Audio simply because of their terrific design and clarity. I originally tried out my friends PPI amp and it gave a lot of thump, but when you raise the volume it was too much thump and crappy sound. With JL Audio, its always clear, unless of course you toy with it and put it on high bass.

[Bak@EMSPowered]

Originally Posted by PHOENIX

Thanks guys, i will be ordering tonight!

Question for you though, don't I want the ohms to match? You mentioned you would have the amp set for 2 ohms so it would have 90 watts and hit harder. Does the ohms matter?

Yes, you want the subwoofers you're running, your amplifier, and how you plan to wire them to match up for the best performance. Have a look at this link for some information about various ways to wire up different types of subwoofers to achieve various OHM ratings for your connection to the amplifier

Subwoofer Wiring Diagrams