Amp selection help needed PLEASE!!!

[Johnny Racer]

Okay so I have decieded to amp the four 6.5's I have in my doors on my 99 Yukon and now I have two choices... the amp I wanted and was recommended by a local stereo joint by me was the following:

Pioneer GM-D9500F
FD Series Class D 4-Channel Car Amplifier
RMS Power Rating:
4 ohms: 75 watts x 4 chan.
2 ohms: 100 watts x 4 chan.
Bridged, 4 ohms: 200 watts x 2 chan.
Max power output: 800 watts x 1 chan.
Pulse width modulated (PWM) MOSFET power supply
4/3/2 Channel operation
Balanced isolator speaker-level inputs
One-pair of pass through RCA outputs
Compression-type speaker terminals
Hi-Volt input level control (200mV-6.5V)
Variable low-pass filter (40-500 Hz, 12 dB/octave)
Variable high-pass filter (40-500 Hz, 12 dB/octave)
CEA-2006 compliant amplifier
Frequency response: 10-35,000 Hz
Dimensions: 8-7/8"L x 7-7/8"W x 2-1/4"H

That one was out of stock when I went to order it online and this is what they recommended in its place:

MTX Audio JackHammer JH404
JackHammer Series 4-Channel Class AB Car Amplifier
RMS Power Rating:
4 ohms: 50 watts x 4 chan.
2 ohms: 100 watts x 4 chan.
Bridged, 4 ohms: 200 watts x 2 chan.
Max power output: 200 watts x 4 chan.
Patented Pure N-Channel technology
LED power, overheat, and voltage indicators
Smart Engage circuitry automatic turn-on circuitry
Bridgeable operation
Preamp RCA outputs
Stereo gain control
Built-in active fan cooling technology adjusts fan speed according to the usage of the amplifier
Nickel-plated RCA level inputs
Nickel-plated screw terminals
Variable high-pass filter (40-5000 Hz, 12 dB/octave)
Variable low-pass filter (40-8000 Hz, 12 dB/octave)
CEA-2006 compliant amplifier
Frequency response: 20-20000 Hz
Dimensions: 14-11/16"L x 8"W x 2-3/8"H

This amp is going to power four of these speakers:

Polk Audio db651s
6-1/2" 2-way Slim Mount Coaxial Speakers (Marine Certified)
Power Handling:
Peak: 330 watts per pair / 165 watts each
RMS: 110 watts per pair / 55 watts each
3/4" Liquid-cooled silk/polymer composite dome tweeter
High pass and low pass crossover filters
Low-mass 2-Layer 25mm kapton voice coil former
Frequency Response: 50 - 22,000 Hz
Sensitivity: 92 dB
4 ohm Impedance

Now... for not knowing much about stereo stuff, I have been told it is better to have an amp that has too much power as opposed to not enough power. As you can see, the Pioneer appears to me to have more power at 4 ohms (75 watts x 4 chan) versus the MTX at 4 ohms (50 watts x 4 chan). They appears to be the same at 2 ohms and bridged at 4 ohms. Not sure about the max output seeing that the MTX is 200 watts x 4 chan and the Pioneer is 800 x 1 chan.

Soooooooooooooooo, I am wondering if this MTX amp was the right way to roll. What can your stereo guru's tell me bout this mess? Did I go in the right direction? Should I stick with the Pioneer? Are they both junk and you got something else in mind???

Really need some help here.

Thanks in advance.
Mike

 

[Done Deal DR]

I think both might be over doing it in all honesty. Your speakers are rated to handle 55W RMS, and even though the MTX is rated at 50W RMS, they (better amp manufacturers like MTX, Alpine, etc) typically understate their power levels and I wouldn't be surprised if it actually put out 75W+ RMS and the Pioneer put out 100W+ RMS. If you overdrive speakers you run a good chance of blowing them.

With those speakers, I'd be looking at amps from decent companies rated at no more than probably 50W RMS. Most amps these days will come with a birth certificate to show what they actually put out, and as long as its around 70W or less you'll probably be fine. Even if they only put out 50w RMS, that is still more than double what any aftermarket headunit will put out, and it will be a massive difference.

P.S. - Your speakers are 4 ohm speakers, so the power levels you should be looking at on the amps are the 4ohm levels. No other figure matters.

Let me know if you have any questions. I'm not a professional, but I've been doing it as a hobby off and on for around 10 years and should be able to answer questions about everyday setups like this.

 

[Johnny Racer]

Shit... that helped a ton. The one guy that sold me on the MTX pretty much said the same thing, you can have a larger amp but you dont really want to exceed like 20% what the speakers can handle or something like that. So from the sounds of it, the MTX will do me just fine and honestly, I cannot complain since I got it for the same price as the Pioneer... there was an $80+ difference in the two and if I am not happy with it... guess I can send it back. Something tells me I will be though.

One last thing... I am order the following to install the amp, this stuff should work right? Good quality and all?

http://www.crutchfield.com/p_211ZN5450/StreetWires-Zero-Noise-5-4-channel-Patch-Cables-16-4-feet.html

http://www.crutchfield.com/p_211PSK08B/StreetWires-Power-Station-PSK08B.html

http://www.crutchfield.com/p_211UCT1425/StreetWires-14-gauge-Ultra-Cable-Speaker-Wire.html

I am going to mount the amp under the passenger rear seat and pull the rca cables and speaker wires through the center of the truck under the carpet like I did with my iPod cable. Power wire and remote lead will run down the passenger side rocker area. The only PITA thing I see is going to be the speaker wires... connecting the new wire to the old stock wires in the dash but I think if I just cut the wires at the aftermarket stereo harness and connect em there, I should be good to go.

Just good to hear that there are people out there that know about this kinda stuff and they agree with what the "professional" sales people tell you and recommend. Somewhere down the road I need a good set of 6x9's for the rear cargo area and an amp for them too. That will be a winter to spring project. Then lastly, replacing the front Polk 6.5's with components. Not sure on weather or not I want to do components up front... I keep hearing in the reviews that they are very "loud" as in tons and tons of trebble. Since I am not going to run a sub, I think it might be over kill.

Who knows, might end up doing a small 8 or 10 incher under one of the rear seats. Only problem there... I have to be able to move it since I fold those seats down constently for the cargo area.

Thanks again for the input and the help.

 

[Done Deal DR]

The only thing I would advise against is the amp wiring kit, I would recommend 4ga as I'm sure that's what the amp is designed for (though I'd need a model # to verify). I've been very impressed with the Kicker amp wiring kits, which can be found very reasonably online.

16 feet should be plenty, just ensure you run is separate from whichever power wire you end up going with. You'll probably want to pull your front seats and pull up the carpet on the passenger side which will save time in the long run and allow you to run the lines properly to where ever you want the amp.

---------- Post added at 11:06 AM ---------- Previous post was at 11:04 AM ----------

Just saw you had in fact posted the amp model, and they do recommend 4 gauge.

"4-gauge power and ground leads recommended — wiring and hardware not included with amplifier"

That should be a good amp. They're all over online for about $160 shipped. Something to think about.

 

[Johnny Racer]

Ah yeah I see that. Found a good Kicker 4 gauge kit complete with everything I need for about $100. Done deal.

Thanks again for all the help my man.