Exile Audio X800.4
Disclaimer: This review is strictly "my opinion", and should be taken as such. Any information provided should be considered yourself, as I am not a "professional reviewer", nor am I an "expert" on amplifier design. Also, I am not paid or compensated in any way (other than getting to play with the product in question for a short period of time) by the manufacturer of this product, so don't expect any portion of my review to be "sugar coated"
Awhile back I had the opportunity to review an Exile X600.4 amplifier. If you are not familiar with Exile, they are a new company formed from some Phoenix Gold refugees. They have a solid lineup of entry level products with simple, effective construction, competitive performance, aggressive looks, and a nearly unmatched fit and finish quality.
Like many audio products of today, they are manufactured in Asia (China for this specific model and I believe most, if not all of the others). For some this is a critical issue. Since nearly all semiconductors are manufactured in Asia these days, along with PCBs (printed circuit boards), a domestic amplifier is really only a chunk of American aluminum stuffed with foreign parts. To me, the real critical aspects of amplifiers are engineering, and innovation. My understanding is all Exile products are engineered here in the USA.
Shortly after reviewing the X600.4, Morgan from Exile informed me a highly improved model with far more power was on its way. The new X800.4 was to be the big 4-channel needed to keep up with Exile's mono amplifiers. When Morgan informed me he had one he would loan me for a bit to test out, I was anxious to see how it would stack up.
For reference I highly suggest reading my previous Exile review here: X600.4. I go into a bit more detail about cosmetics and the amplifierís overall quality in the first review. For this review I would prefer to focus more on performance, and what is new about this amplifierís design. As with my other reviews, I will break this down into a few topics, the first of which is construction.
One word defines this amplifierÖ evolution. Exile has really begun to evolve in a short time. This amplifier is a direct evolution of the X600.4. The X800.4 offers increased power, is much more overbuilt, and has additional creative design aspects. And, it is all of this for a list price of only $500.
The box is solid with supportive foam inserts, specs clearly printed on the outside, and with high quality printing all over. A set of wrenches and screws are included.
For the most part the X800.4 is built with the parts of two X600.4s all in one chassis. Dual power supplies are used, and each has no less than four TO-220 sized MOSFETs. I have no clue what MOSFETs are used due to the Exile device clips used to mount them. Maybe Exile can send me a clip removal tool with the next amp (hint hint). Each power supply then has a pair of dual diode packs for rectification purposes. Capacitance consists of three 2,200uF caps per supply on the input, and four 3,300uF, 50V caps per supply for rail stiffening.
Additionally, the transformers used have mounting rings under them. This is a nice feature many manufacturers are moving towards, since it is easier for mass production, places less strain on the circuit board, and helps with winding the transformers themselves.
Output devices are plentiful. Four TO-3P sized devices are used per channel. Channel preprocessing is cleanly laid out, and appears consistent with the design of the X600.4. All of this adds up to a big leap in parts count, and value. This amplifier has the resources need to be competitive with many more expensive products on the market.
Exile added some new and appreciated innovations to this amplifier. The first is a daughterboard for the additional signal processing included with the amplifier. Exile now offers bandpass filter capability, and that will come in very handy for many installation situations. Bass boost is also included. Both of these features require more parts to implement and to conserve space, Exile chose a daughter card on standoffs. The connection between the boards is with a very common and reliable connector found in many industrial products. Also, a cheaper ribbon was not used, and instead individual rainbow colored wires transfer the signals.
Exile also chose a small surface mount PCB for the power supply controller board. I am very pleased to see this, and hope Exile continues towards even more modular surface mount boards. A signal processing board built like this could improve signal to noise, and allow board real estate for even greater processing options.
Three 40A fuses are installed in one end of the amplifier. This is quite a bit of current for an amp of this size. For these fuses to blow, either the amp is very powerful beyond its ratings, or the user would have to really be abusing it.
The amplifier has a remote level control, but I did not find the controller in the box, and really donít know much about it. I am not a fan of remote controls, so I often donít pay much attention to them.
High quality and heavy duty terminals are used throughout the design. The RCAs are pretty standard, and have a pair of screws holding them securely to the chassis.
Large buss bars are used in the amplifier for high current power transfer. This is typical of all Exile designs I have seen.
A pair of large diodes are used across the inputs to help protect against reverse input wiring by blowing the fuse or circuit breaker in the installation.
All of the parts used are good quality, and thoughtfully implemented.
Issues with the amplifier:
When I first opened this amplifier up, I did notice a few flaws. I found two spots where solder was splashed onto some of the amplifierís parts. Both of these spots would not effect the amplifier as they existed. The issue is the one on top of the transistor had no metal to attach itself too. Using an x-acto blade, I picked it off, and the glob broke loose with nearly no pressure or effort. If this amplifier were installed, the vehicle vibration would have easily caused this to fall loose, and if it managed to fall into the wrong place on the amp, serious problems would have resulted. I am not too concerned with this instance, as I believe this amplifier is an early production model, and bugs in its process are probably still being eliminated.
I also noticed a bubble under the finish on one of the amplifier's end covers. I have taken the photos below to illustrate this.
The second photo is after I rubbed the spot with my finger wondering what it was. The bubble grew! Well, on the underside of this end cover several marks were made with a paint marker. My feeling is this is not a shippable end cover, and had some sort of known flaw on it which would not show up in a retail product. The X600.4 I review before showed no signs of any of this.
Initially I connected the amplifier to my set of home speakers I use for nearly all my amplifier repair testing, and amplifier sound quality testing. These speakers are 8 ohms, so they present nearly no load to a car amplifier, and they are home built with some relatively high end drivers (Seas Prestige). They are also very revealing of any flaw in the acoustics of an amplifier.
The X800.4 sounded great. I will admit nothing really jumped out at me as being significantly impressive, but the amplifier did not skimp on sound either. It was neutral and detailed, and since I am in no way Mr. "Golden Ears", nor should my opinion on how something sounds be relevant to anything, I feel its sound quality abilities are very competitive.
I decided to take some raw output power measurements. Due to the limitations of my 40A power supply, I can only test a channel at a time, or bridging with smaller amplifiers. I first measured the maximum unclipped output voltage with no load present. The X800.4 would do 28V AC with a 1kHz test tone and no load.
If you calculate this out, 28V is just shy of 200W. Next I presented the channel with a 4 ohm resistive load.
Output voltage fell to 24V AC, which is equivalent to almost 150W a channel. This is 20% more power than rated, and is highly respectable.
Under load on one channel, I checked the DC input voltage to the amplifier, and it was stable at 13.86V DC. This is similar to what you would find in a vehicle with the engine running.
Now, you may wonder just how useful this test was. If you consider music is dynamic, I feel testing one channel of a multi-channel amplifier is going to tell you something useful. When the output voltage falls as load is applied, this is typically the power supply's rail voltage being pulled down. If I loaded all four channels, the output would likely have fallen even more. But, this is playing a test tone into a resistive load. If instead I played a dynamic load, the amplifiers internal capacitance comes into play and will help maintain rail levels. I would not be surprised if this amplifier could do around 175W a channel into 4 ohm loads while playing music. However, I have no way of proving any of this.
Way to go Exile! This is a huge step in the right direction as far as I am concerned. It beats out the X600.4 easily, and really takes up minimal additional space. Couple this amp with the new X5 mono beast, and any basshead or daily user should be beyond pleased. For someone on a tighter budget, this amplifier easily has the goods to power a whole system by itself, and do it with a very respectable level of output. Sound quality is solid, and so is the feature set. The onboard crossover is powerful, and should be ample for any intermediate installation, or even some more advanced installs.
I would like to thank Morgan at Exile for providing me with the opportunity to review this product!