MTX Thunder X704

Following a trend away from classic design the MTX X704 has all its controls and connections on the front drop, although to follow good practise the RCA sockets are as far away from the power connections as possible. The power and speaker wires are all expected to be used unterminated (unless you use bootlace crimps like on the end of a lace) and you are supplied with the three sizes of Allen key to use them. You also get two sets of four-wire edge connector plugs intended for use with speaker level input and an excellent manual.
The brand badge on the top is simply luxuriant and is all shiny and has a small red LED in its visual centre. This looks like it would be desirable as the buckle for that sort of belt that could instead sport a Harley Davidson logo. (Hey, if I’d put ‘Triumph’ the Americans would only associate that with George Michael’s video) Big and brash, it tells you something about the manufacturer’s intent before you fire it up.
There really is a very weighty heatsink indeed on this amp. The thickness of the ally fins is impressive.
Also impressive are the crossovers. Simple in operation they look a bit daunting and mixing-desky but, like a mixing desk are simple in reality. You can choose to be highpass or lowpass and can switch them all on or off independently. Which means you can also use the amp’s four channels to run a set of component speakers with bandpass crossover settings. The terminals are all set in resin blocks and intelligently angled up and at you (like the Harman Kardon’s) instead of your having to get in the same plane as the nice clean top surface with your scratchy tools.
– Class AB
– 4 x 70w RMS @ 4 Ohms (CEA-2006 Compliant & certificate says tested at 71w)
– 4 x 105w RMS @ 2 Ohms
– 2 x 210w RMS @ 4 Ohms bridged (certified at 429w total)
– Black anodised Aluminium extruded heatsink with large badge on top with red LED
– 8mm power terminals with Allen headed grub screw bare wire socket connection, 6mm for remote wire, 5mm for speakers (micrometer measured)
– High level connection via dual edge type sockets looms supplied
– 4Ch RCA input
– Adjustable input sensitivity: 0.2V to 5V
– Stereo & Mono operation
– Frequency response 20Hz to 20kHz
– Signal to Noise Ratio 85dB
– Channel separation not quoted
– High Pass Filter 12dB per Octave 40Hz to 800Hz or by 10x multiplier switch, 400Hz to 8kHz
– Band Pass Filter 12/24dB per Octave variable anywhere between 40Hz to 8kHz
– Low Pass Filter 24dB per Octave 40Hz to 800Hz or by 10x multiplier switch, 400Hz to 8kHz
– Fuse Rating 30A x 2
– HxWxD(mm) 50 x 315 x 210mm
– Complete with three Allen wrenches and mounting screws
Review by Adam Rayner
MTX are the makers of the utterly Bonkers 22 inch Jackhammer subwoofer (see ‘Hammer Your Brains Out’ under install features) and are famed for making equipment with huge potency. Indeed, one of their ready made subwoofer box lines was so insane that those who heard it gave comments that led to the rise to a new slogan. ‘Holy ****!’
Thus it was with surprised delight that I discovered how good this amplifier sounds.
Evidenced by the sweetness of the high frequency handling characteristics, this was lovely and was even better than the Harman Kardon that had just impressed me on the test bench beforehand. Flashy-looking with the lumpy logo plate it seems as if it would be all mouth and no trousers but it rocks. I could see some folks being a bit put off by how busy-busy the crossover controls seem to be, with a lot of push switches to turn things on and off. The only objection would be that in the real world we sometimes have loose objects in the boot and they can end up biffing into the amp’s panels. Some big Japanese amplifiers have been provided with a big rubbery band to insulate the power terminals to protect against shorts by metallic drifting objects. Thing is, while inferior cheapie three-position switches are commonplace if a bit nasty, these posher push-microswitches are resistant to being accidentally switched. Imagine what would happen if a powerful active tweeter channel suddenly had its crossover on/off switch bished and then suddenly got full range up it. It could really screw your tweeters up and you mightn’t even be aware of it as you would if your woofer’s crossover got switched off. That’d just make the woofer go all ‘middly’ and not harm it. (Lead guitarists’ screaming solos come out of Marshall stacks with 12 inch speakers, after all.) However it’s a minor gripe and only the silly who are also unlucky could ever find this an issue, so no matter.
Again, that slew rate sounds like it’s a lot of volts per second, which is what that ‘fast rise time’ lovely high frequency performance factor is so dependent upon. The output was really crisp with all the odd percussive sounds from shakers and tinkly things in the more Latin numbers from the Focal Spirit of sound #6 disc coming to the fore. Stuff like brushes on high hats are hearable as a mass of sounds making the rustle, not just an ill defined ‘pish-titty-pish’ that’s normally heard.
Bass still hit hard from snare and kick drums and when cranked up, the SPL side of the AudioControl SA-3055 RTA registered 126.8dB. This seems a bit lower than all but the small Genesis Profile four and the PowerBass ASA600.4. This shows that the amplifier’s guts sacrifice a little brute power to the cause of high fidelity which is slightly fabulous given the brand’s image. That said, I guess it simply isn’t an issue as this really is most likely to be running mids and highs or simple full range in any likely MTX system and if you want to make big audio dynamite, well they do have amplifiers fit to drive their Jackhammer, so there’s an answer to that!
Overall 8.4
Sound Quality 9
Power Output 8
Features 9
Build Quality 8
Value For Money 9