Wiring an amp

[fraserjr]

@Mainah I just noticed that the MB Quart is an A/B amp too. Its sitting in my garage waiting to be installed but giving that info, I am wondering if I should return it and get this one instead:

https://www.amazon.com/Rockville-Am...&sr=8-1&keywords=marine+class+d+6+channel+amp

Thoughts?

 

[jcyamaharider]

@Mainah I just noticed that the MB Quart is an A/B amp too. Its sitting in my garage waiting to be installed but giving that info, I am wondering if I should return it and get this one instead:

https://www.amazon.com/Rockville-Am...&sr=8-1&keywords=marine+class+d+6+channel+amp

Thoughts?

Are you going to be playing your stereo all day long cranked to the max in 100+ degree heat???? If not then you will be fine. I have 2 of the MB quart class A/B amps and they get ran hard and do just fine. Ask everyone that boats with me.

 

[Mainah]

@fraserjr
Really good class D amps are around 90 percent effcient. Really good class A/B amps with mofsets like the mb quart are around 75-80 percent efficient.

So lets say you are drawing 200 watts on average. The class D amp will "waste" 20 watts while the class A/B amp will "waste" about 40-50 watts. So lets say the average delta is 25 watts for your use case. Now multiply that delta over time and it just means will have less play time out of your amps. Running only a single 4 channel amp pishing 4 polk dbs you are likely fine unless you want to run for days with recharging the batteries fully.

I am dubious about the Rockville brand. They promise a lot for very little money, use some bs marketing about the grade of the internal components and I wonder how well that housing dissipates heat.

 

[FloJet]

With this amp, the only thing I would say is research a little more to make your decision. It has a channel separation of >60db. Which is odd for them to list that like that. Most of the time you want to see what the DB sensitivity rating is. >60db doesn't always mean a bad thing for channel seperation but with them not listing the sensitivity rating, I am very skeptical of the amp. For what most boaters are looking for, sensitivity rating is one of the most important to look at IMO. Also an amp with 8 channels at that price point is just sounds way too good to be true.

• Minimum THD: <0.05%
• Damping Factor: >200 at 100Hz
• Input Voltage: 150mV - 6V
• RCA Line Output
• 80A Fuse rating!
• Channel Seperation: >60dB
• Input Impedance: 22K
• Dimensions 6.7" W x 2" H x 11.5" L

 

[FloJet]

Also after looking at the specs closely, I don't see voltage rating. Meaning it's important to know what voltage it runs optimum. You don't want to get something that is rated high. I'm sure its not higher than normal amps, but again it's an important spec that really needs to be listed for stereo junkies.

• Rockville RXM8BTW 8 Channel 1500 Watt Marine Amplifier W/Bluetooth White
• Compact design and extremely high power (Do not be fooled by the compact size; this amp is a beast!!!)
• 1500 Watts Peak System Power
• 750 Watts RMS System Power
• RMS Power Output at 4 Ohms: 65 Watts x 8 Channels CEA Rated
• RMS Power Output at 2 Ohms: 95 Watts x 8 Channels
• RMS Bridged Power Output at 4 Ohms: 190 Watts x 4 Channels
• Peak Bridged Power Output at 4 Ohms: 380 Watts x 4 Channels.
• Configurable to 8-6-4 channels or 6.1 or 4.2 System
• Bluetooth Wireless with Auto Pairing
• UV and Salt Water Resistant Paint, Silk Screen and Heat Sink Enclosure
• Marine-Grade Conformal Coated Boards Resist Corrosion from Salt Spray and Moisture
• LED Power and Protect Indicators
• TI Digital Class D Audio Topology
• High Speed MosFET Power Supply
• Studio Grade Bipolar Output Stage Transistors
• Micro Size Architecture with SMD Component Circuitry
• Compact Design and High Power
• Non-Corrosive High Gloss White Aluminum Casing
• Selectable Bass
• Non-Corrosive Brushed Aluminum Casing
• Conforms to the American Boat and Yacht Council (ABYC) Marine Electronic Standards
• Bass Equalization: Fully Adjustable 0 - 12dB at 45Hz
• 4-Way System Protection Circuitry (DC, Short, Thermal, Overload)
• Heavy-Duty Aluminum Alloy Heat-sink
• Stainless Steel RCA Level Inputs
• Stainless Steel Bolt Down Molded Terminals
• 4CH / 8CH Input Selector Mode
• Independent Crossover Controls between CH1-4 and CH5-8
• Full Range / Low Pass / High Pass Configurable
• Variable High-Pass Filter: 50Hz - 250Hz at 12dB/per Octave
• Variable Low-Pass Filter: 50Hz - 250Hz at 12dB/per Octave
• Frequency Response: 10Hz - 40KHz
• S/N Ratio: >100dB
• Minimum THD: <0.05%
• Damping Factor: >200 at 100Hz
• Input Voltage: 150mV - 6V
• RCA Line Output
• 80A Fuse rating!
• Channel Seperation: >60dB
• Input Impedance: 22K
• Dimensions 6.7" W x 2" H x 11.5" L

 

[Jgorm]

Sometimes you win buying cheap junk, sometimes not. I guess it's 10x cheaper than a comparable amp, so buy two and keep a backup on hand for when it craps out. I'd rather buy a car amp that has a bunch of reviews instead of this amp with no reviews and outrageous claims for the price. It's probably a tiny $30 amp inside a big heat sink.