Rockford vs MTX brand amp?

[Flyin11]

I'm still thinking about another amp for my system even though it's sounding pretty sweet right now but I know a lot of people around here have good insight so I value what is being said and wanted to see what people would recommend between these 2 amps I'm looking at to use with my 2 8ohm 12" Stage 1 Punch subs in parallel that are in a ported box. I'm looking at either the Rockford Fosgate Punch 325.2 when bridged at 4ohms is 325 X 1 or the MTX TC3002 when bridged puts out 300 X 1...MTX says it's amps are usually under certified and usually have 3% more power than what they are rated. which sounds really good. The MTX is my better choice as it's a lot shorter in width and I don't think the Punch would fit where I want it to. I have never had a Punch before and it does come with a bass knob which is really good to tune with when driving down the road but the MTX does not. I have never had any issues with a MTX amp as the last one I had before it got stolen was kick butt and the best I ever had. They both are equal in every aspect except for the bass knob, wattage, and the Punch doesn't have high level inputs, which I don't need anyways but just pointing out. Of course the size of the amps are different too.

Which one do you guys think is a better choice? The Punch or MTX? Thanks

Just for specs (Not where I'm buying it from):

Punch:

http://www.crutchfield.com/S-BVnK2CX...=Punch+325%2E2

MTX:

http://www.crutchfield.com/S-BVnK2CX...02&i=236TC3002

[junglejuice]

I am not familiar with either models but I have used Punch amps in the past and found them to be excellent, but these were the dsm's so they are old school now but very reliable and very under-rated....

[ppia600]

If they are close in power output, get the MTX.

[ocool_15]

To your ears the 325W will only gain you ~.35 dB in volume over 300W. Which I would never concern myself with. Both manufacturers "under rate" their amps but again its not enough to really matter.

The MTX also appears to have a Bass knob in your link
"variable Thunder EQ bass boost with wired remote control (0-18 dB at 40 Hz)"

My preference has been towards Rockford as in my experience I have found them to run cooler and have previously found them more reliable. I think you will find more Rockford amps are sold them MTX.

A quick search of ebay shows 123 New and 75 used Rockford Amp listings on ebay and 55 new and 19 used MTX amplifiers

[ppia600]

(I recently sold 4 broken fosgates and one used mtx on ebay. At least the mtx had one channel still working )

[Flyin11]

LOL

Yeah, I noticed after I posted that the MTX amp does come with a bass remote. Which I thought was pretty cool but I didn't notice it till after I posted. I also made a mistake on the percentage thing...MTX amps usually are 10% more power than they are rated...I said 3% LOL My bad...

What about Kicker amps? I could get a great deal for one for 375 X 1 into a 4ohm load but am worried about the length of the amp...Other thing is it has 2 25A fuses...That's 50A and the amp fuse I have now is 20A...30A more pull on the fuse...Just worried that that would be too much power draw and dim my lights during bass hits. Right now I'm extastic that I don't have this happen like in the older cars I have owned. One of my local audio dealers said not worry about my current amp before as I they have put stuff in 2003 Honda Civic's that are way more powerful and never had any issues and they were right. For my current amp anyways that is. He also said that Hondas have great alternators. Should I be worried?

[ppia600]

You'll need to stick with a two channel to run the load you have and to maximize power output. If you are running one of those two 300watt amps, make sure to at least have an 8 gauge wire (using a larger 4 gauge won't hurt) and maybe a 40 amp fuse under the hood. Running them bridged will make them draw maximum current and starving them of voltage and current will make them run hotter.

[Flyin11]

Yeah, I have 8 gauge wire and the fuse under the hood is 60amp

[junglejuice]

Originally posted by ppia600
You'll need to stick with a two channel to run the load you have and to maximize power output. If you are running one of those two 300watt amps, make sure to at least have an 8 gauge wire (using a larger 4 gauge won't hurt) and maybe a 40 amp fuse under the hood. Running them bridged will make them draw maximum current and starving them of voltage and current will make them run hotter.

Sorry I gotta say that is an old wives tale about the voltage versus heat issue, amplifiers are only capable of putting out the amount of power that is available through the power supply so if the rails in your amp run at around 28v with a supply voltage of 14v then the same unregulated amp will only have rails of 24v at 12 input which means using ohms law there is less current flowing through the outputs due to the lower voltages therefore less power and less heat dissipated.

Above is for the unregulated style of amps of which most are but for the regulated amps the power supply section generates much less heat than the output stage anyway due to the fact that the fets are hard on or off not partially on like the output devices which is where most of the heat comes from.

This is one of the often touted "known facts" which unfortunately is baseless.....

[Perry Babin]

junglejuice:
In general, you're absolutely correct. Low voltage (unless it's extremely low -- 8v or less) does not make an amp run hot. However, some of the older amplifiers would run hot if the power supply voltage dropped too low (into the 10v range). The amplifiers had stiffly regulated supplies. This meant that the duty cycle was almost always less than the maximum. When driven hard, the duty cycle would increase which meant less dead-time. The amplifiers didn't have an adequate control circuit and there was significant shoot-through on the power supply FETs at the maximum duty cycle. This caused them to overheat. You could simply lower the voltage on the DC power supply and watch the current increase (no load) and the power supply FETs would begin to overheat. I know of no amplifier that does this now but it really was a problem with a few of the older amps.

There's another argument that losing the ground on an amp causes the RCA shield ground of the signal source to burn because the amp tries to ground through the shield. This was possible on a few amplifiers even though they were in perfect working order. A somewhat common fault on a different line of amplifiers will let them do the same thing but they won't do it if they are in good working order.

Not all wives tales are completely baseless.