ok, i already have a sub and a box to go with it. now its time to choose an amp.

i've narrowed it down to two models: Alpine MRD-M501 or JL Audio 250/1

any suggestions?

also, will i need a Capacitor for this install? or should i be ok without it in this case.

 

i guess it depends on what speaker you are using.... i would say that you will be safe without a cap...

 

Infinity Kappa Perfect 10

 

i would say go with which ever one you can get cheapest... they are both going to give you about the same power... but the alpine will double if you have a 2ohm load...

 

i see. any major difference in SQ between the two?

 

If you are going to run your sub at 2 ohms, I would go with the Alpine. Extra 3 db of output is never bad. Both amps are going to give you good quality. For bass amps, it will be hard to tell a difference at the same wattage.

 

ok, i'm a little unclear on this. its a 4 ohm speaker, just 1 of them, so connected to the Alpine M501 would it not be running at 4 ohms? does tapping into the factory wires have anything to do with it?

thanks for all the help....

 

as long as it is a single voice coil sub. DVC can change things.

If the prices are similar, go with the JL. They are not over-rated like Alpine does.

Better yet, if you have some time, wait for a Zapco Studio 300x to come up on Ebay and pay $300 or less. 460 super-clean watts into a sub and a nice crossover.

The Infinity Kappa is fairly efficient, so the JL should be enough. It also is nice in that it is designed for a very small sealed box.

 

oh yes, its single voice coil...

thanks

 

What do you mean by this. Are you saying Alpine overates their amps or that Alpine is overated? Either statement is not true. Alpine is one of the first companies to adopt the new system of measuring power, (CEA-2006). As for Alpine being overated, that is a matter of opinion.

 

Just looked at the Alpine site and see that they started this standard in 2004.

Looky here at the specs for the 9821 head unit (copied right from Alpine1.com):

Key Features
CEA-2006 Power Ratings
16W x 4 (4ohm@14.4V 1% THD+N)
S/N 80dBA (Ref: 1W into 4ohm)

What is the CEA-2006 Specification?

• 45W MAX x 4 High Power Amplifier
• Bass Engine®


Notice the drop form 45W advertised to 16W measured? This is a unit that they were selling at 45 watts.

Looking at the specs for the amp in question here, the M501, I see that the measured signal to noise ratio is 60! That is God-awful. Don't put anything in your system under 80. Mine are all 95 to 105.

Alpine used to make all good stuff. I had a head unit about twenty years back when it was all made in Japan, made for performance and not marketed nearly as much.

 

I will agree with you on the new stuff. Alpine is now a mass market brand and not the cream of the crop they once were.

As for the inflated head unit specs, name a company that does not do this. Most people will be running after market amps and the head unit power is irrelevant. However, the new internal amps of the Alpine head units provide some of the best head unit power out. That is why you need to hook them directly to the battery.


Anyway, off topic of the post, sorry. For a bass amp, go with either one but, I too personally would go with the JL.

 

The stuff is mostly going downhill. I wouldn't buy the new amps. Mine is 17 years old.

The A/D/S speakers I run now are not as good as the old 320is.

The sub delivers good sound quality for me, though.

 

thats a good point you make 9'er

the signal to noise ratio of the JL 250/1 is 95 as compared to the Alpine's 60

very interesting...

 

ok, so i got the JL amp today. cheaper, more power at 12V, and the S/N ratio difference were the selling points for me.

when tapping the line to the factory amp for input, shall i set the amp to high or low Input Voltage?

 

You can try them both, but I would think it needs the LOW VOLTAGE input since your using a preamp signal.

 

that's what i thought, just wanted a second opinion...

thanks