What kind of amp should i use?

Question

to power 4 Alpine SPR-13C.

Here are the specs :

Peak Power: 270W

RMS Power: 90W

Frequency Response: 70Hz - 27kHz

Sensitivity: 86dB, 1W/1m

Installation Diameter: 117mm

Depth: 55mm

should i use a 4 channel amp? that runs at 4 x 85 RMS?

somthing like this amp 'Ground Zero Titanium GZTA 4000TX':

4 x 85 WRMS @ 4 Ohm (14.4 V, 1% THD)

4 x 120 WRMS @ 2 Ohm (14.4 V, 1% THD)

4 x 145 WRMS @ 2 Ohm (14.4 V, 10% THD)

600 watt maximum output power

2 ohm stable

Bridgeable

MOSFET power stable

Adjustable Lowpass 30-250 Hz

Adjustable Highpass 30-500 Hz

High Level Input

is 4 x 85 WRMS @ 4 Ohm (14.4 V, 1% THD) its maxium?

Answer 1

Depending on the professional who is installing it, you can go higher rms but make sure that the amp is set so it isnt too high. Often times companies will overrate the rms per channel on an amplifier. If you buy an excellent quality amp, this is generally not the case. Many top notch companies will underrate their amplifiers, so you can get say 65 watts per channel instead of 85 and still get the same loudness but usually better sound. A Class D amplifier is typically an excellent choice amp and is considered competition worthy. These amps often are underrated for wattage and will get you better sound than a cheaper amp. (You rarely see other class amps ever rated as Class C etc) You can usually find a lower wattage class d amp at a reasonable price. Kicker, mtx, alpine etc are some examples of companies that have class D amps.

As a side note 1% THD (total harmonic distortion) is pretty high compared to other amps out there. I've been told to look for .10% or less as standard rule of thumb when looking into THD

Answer 2

Yes, 4x85 is the maximum per speaker rating in RMS. This is the constant power they are able to handle. That amplifier would work, but you'v egot better options. I would recommend name brand. Alpine's own amps are high quality and I would recommend them. Class D amps are good, but they are generally used for subwoofers. Get a decent four-channel amp with anywhere between 45-90W RMS and you will be in business.

Answer 3

Class D amps are for subs only, to high THD for mids and highs. Look for a  4 channel amp, unless your an audiophile your not going to hear the difference in an amps THD rating, assuming it's not a Class D lol.