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Hey guys,

If you saw my post in the amp section, you would know that something happened and now my amp and sub are both fried.. Therefore I have been looking at new equipment. Here are the setups I was looking at and I would like your opinions:

I will definitely be going with 2 10" RE RE series subs. 175W RMS in a D4 VC configuration, leaving me with wiring options of only 1 and 4 ohms(correct?). The amps that I have been looking at are the Kicker ZX750.1,the Alpine MRP-M650 and the MRP-M500

The ZX750.1's specs are:

Performance
RMS Power Output (Watts x Channels) 750 x 1
Peak Power Output (Watts x Channels) N/A
Power at 4 Ohms (Watts x Channels) 375 x 1

Minimum Impedance Bridged
Minimum Impedance Unbridged 2
Frequency Response at Rated RMS Power 20-200 Hz
THD at Rated RMS Power 1%
Signal to Noise Ratio 95 dB
Input Voltage 14.4v
Features
Amplifier Class D
Low-Pass Crossover Frequency 50-200 Hz
Low-Pass Slope (dB/octave) 24 dB
High-Pass Crossover Frequency N/A
High-Pass Slope (dB/octave) N/A
Bass Boost 0-18 dB
Bass Boost Frequency 40 Hz
Fan Cooled No
Fuse Rating 40 x 2
Speaker Level Inputs Yes
Preamp Outputs 1 pair
LED Power Indicator Yes
Width (inches) 14-3/4
Height (inches) 2-3/8
Depth (inches) 9-11/16

The MRP-M650's specs are:

* CEA-2006 Power Rating ([email protected] = 1%THD+N), S/N 65dBA (Ref. 1W into 4Ohm): 400W x 1
* RMS Power (at 14.4V THD+N, 20Hz-20kHz):
o Per channel into 4 ohms: 400W x 1 (0.08% THD)
o Per channel into 2 ohms: 600W x 1
o Bridged 4 ohms: 1000W x 1 (0.3% THD)
* Bass Engine Sound Tuning:
o Crossover Frequency : 50Hz - 400Hz LP (-12dB/oct)
o Subsonic Filter (Fixed): 15Hz
o Bass EQ Frequency (Fixed): 50Hz +12dB
* Frequency Response: 20Hz - 200Hz (+3,-3dB)
* Signal to Noise (S/N): 90dBA (Reference to Rated Power)
* Input Sensitivity (For Rated Power): 0.2V to 4.0V (1.0 at Center Detent)
* Input Impedance: 10k Ohm
* Speaker Impedance: 4 or 2 ohm Bridged
* Power Requirements: 14.4V DC (11V to 16V)
* Fuse Type: 30A x 2
* Dimensions (W x H x D): 11-1/64" x 9-31/64" x 2-23/64" (280mm x 241mm x 60mm)
* Weight: 3.7 kg.

The MRP-M500's specs are:

Classification Class D
Input Voltage 14.4V DC
Standard Warranty 1 Year Limited
Manufacturer Alpine Electronics, Inc
Dimensions 2.36" Height x 10.63" Width x 9.53" Depth - Foot Print
2.36" Height x 8.27" Width x 9.53" Depth - Heat Sink
Manufacturer Part Number MRP-M500
Channels 1 Channel
# Additional Information Thermal Control: Thermal Management Control
# RCA Output: Gold Plated RCA Input Connectors
# Crossover: Adjustable Low-Pass
# Connector Plating: Gold Plated Input, Output, Power and Speaker Terminals
Output Power 1 x 300W RMS (20Hz to 200Hz) @ 4Ohm 1% THD+N
1 x 500W RMS (20Hz to 200Hz) @ 2Ohm 1% THD+N
Manufacturer Website Address http://www.alpine.com
Brand Name ALPINE
Certifications & Standards

CEA-2006
Impedance 2Ohm to 4Ohm
Signal to Noise Ratio (SNR) 100dB(A)
Product Model MRP-M500
Product Name MRP-M500 Car Amplifier
Product Type Car Amplifier


So here is my dilemma. The subs will require approx. 350W RMS. The MRP-M650 would suit this best, providing 400W @ 4ohm. The M500 only provides ~300W RMS at 4ohm, but I would assume that Alpine amps are a bit underrated, right? And the ZX750.1 provides 375W RMS at 4ohm, which is also in the sweet spot.

So my questions are basically what amp would do the subs justice, and should I go for more power and keep the gains down? Also, in everyone's experience, how much can these amps be underrated in their power? Can anyone suggest any other amps that fit this range, both wattage and price($150)?

Thanks guys! :)

I've had a Kicker kx600.1 running my subs (kicker compvr's) for about 5-6 years now. It's been a solid amp. I haven't really pushed the amp to it's limits, kinda' like I run it at an idle and have only reved it up a few times. But it'll put out like a cheap hooker if you ask it to. I'd buy another Kicker amp to power subs no question.

I also have a four channel MRP-F550. Good quality and it produces nice crisp clean sound to my 6.5 components. I would also feel comfortable buying an Alpine amp to power subs.

Realistically you wont hear a difference between 120-180 WRMS. 120 WRMS is more than enough to get these subs moving.

Now it comes down to price.

Now I gotta ask, do you have speakers in the doors? Are they amped?

Now might be the time to invest in a decent 4 channel amp that can drive both the subs and the fronts. Sure it will cost a few more bucks, but its cheaper than buying another amp for the fronts later on.

The American Bass SQ600 will drive the subs well with 150 WRMS x 2 @ 2 Ohms available.

The AB SQ945 will power the subs at rated power (180wrms @ 2 Ohms x 2 Ch) and provide you with 150 WRMS X2 @ 4 Ohms for front speakers...

Ryan,

I already have a 4 ch eclipse amp for my front components(diamond audio CM3's) so I am just looking for low end replacement. I appreciate the honesty about not hearing the difference. The RE's are dual 4ohm and I am getting 2, so I would have to wire it at 1 or 4 ohms, right? Is it ok to use a 2 ch amp for the subs?

Oh ok, well you are all set then!

The American Bass SQ600 would work good.

Also Massive P200.2 Cadence XA125.2, XA175.2

There may be more...

Yup, any of those would work and you're not going to hear any difference in 20-40 watts with those subs... You can run a 2 channel amp as long as you run each to a separate channel for a 2ohm load.

cargodz wrote:Yup, any of those would work and you're not going to hear any difference in 20-40 watts with those subs... You can run a 2 channel amp as long as you run each to a separate channel for a 2ohm load.

dont you mean 4 ohm load?

If you're running 4ohm dual voice subs then you can wire each for 2ohms to each channel on an amp that's 2 ohm stable

cargodz wrote:If you're running 4ohm dual voice subs then you can wire each for 2ohms to each channel on an amp that's 2 ohm stable

oh ok I see what you mean. I actually just purchased the cadence amp mentioned above from Ryan, so that is rated at 375W RMS x 1 at 4 ohm bridged, so I will just wire it up to see a 4 ohm load. I am going to assume it is not 2 ohm stable since there are no power ratings for it at 2 ohms.

Actually those Cadence amps are 2 ohm stable... The XA175.2 delivers 175w x 2 @ 2ohm... So you have a couple options :)