NJ_DRIVER

I currently have these subs and Ive heard that you should match amps and subs together by manufacture but if sony amps suck I'll get something better.

i8acobra

Their current stuff pretty much sucks. I have two of the last good amps they made. I have 'em in storage and won't be selling them anytime soon. I you want a Sony, find one of these.

The Sony XM-7547 Mobile ES 75x4 amp:



Dual power supplies:

DTN

I have had a Sony xplod setup for 5 years with no problems. Guess what? 5 years ago people said their current stuff sucks.

187sks

IMO all Sony Xplod stereo stuff sucked then and continues to suck now.

radu_rd2

I don't see any compelling reason to match manufacturers.. As long as you match the RMS power, you should be good

i8acobra

Well, the new ones with the same power rating as the one I posted are 1/3 the size and weight. Do the math.

faithofadragon

THe general idea is you pay to play why is it that comparable jl audio amp and sub are 3 times as expensive as Sony

I still love old school phoenix gold though

DTN

Even more importantly is the impedance matching. RMS does not mean anything if a 2 ohm setup is used instead of a 4 ohm setup. Distortion and speaker damage can occur. You can always go lower then the power required by the speaker, but if the impedance is wrong then the setup will provide infidelity and possible damage. If you match impedance and lower the power then you just end up driving the speaker less then it's potential.

DTN

Sony has been using class D amplifiers for some time now. http://en.wikipedia.org/wiki/Class_D_Amplifier Class D amplifiers are much more power efficient then Class A, or AB amplifiers without sacrificing quality. They only work on subwoofers because of the nature of square waves through a capacitive/inductive circuit.

Class AB amplifiers run at about 70% efficiency. Class D amplifiers run at nearly 90% efficiency. All that extra power gets pumped out to the speakers rather then generating heat in the amplifier. While some heat is generated in a class D amp, it's not much under ideal conditions. Heat is really the only limiting factor on how big and heavy an amplifier has to be.

I can see amplifiers becomming much smaller then the ones Sony is putting out. The only real limit is the heat factor. When you start making more energy efficient components, they take less space.

Old tube style amplifiers from the 60s take up an entire cabinet, while newer ones generate 1000x the power in a package which is 1/100 the size.

I'm doing the math and it sounds like Sony is making technological advances.

There are a few companys which have stood the test of time. I trust companies which have been around for a long time to create a good product. Sony has been around since 1945. They specialize in electronics. I would not trust a start-up company which makes large components. How is it that everyone says Sony makes bad products? Seriously... I would question rockford fossgate, a company which has 1/2 the experience of Sony.

Sony is the company which made the transistor radio popular. They've been working with signals for longer then any other company out there. They are a large company which has the assets to hire signal electronics engineers. Signal electronics is different then most other electronics. You can see that whenever you see "impedance" rather then just "ohms". Impedance refers to pure signal attenuation rather then resistive signal chopping. Making an amplifier is not something which just anyone should attempt.

I'm just saying... I have no idea what people base "Xplod sucks" off of, but I have not found a single problem with quality or clarity, or functionality yet.

i8acobra

Open a new one and open an old one... same components with smaller heat sinks and smaller (single) power supplies. The XM-7547 is all aluminum and has dual power supplies. The new ones have alot of plastic. This goes for their home stuff too. My old Sony ES receiver weighed a ton. The new ones are very light in comparison. This isn't modern technology, this is cost cutting.