Mutant MT5AS

Compact under seat subwoofer with a five inch driver with 50w RMS amplifier. There are RCA and speaker level inputs. The crossover may be adjusted between 80Hz and 200Hz and there are Allen headed bolts holding the matt black silky-coated panels together. A 3.2mm microjack is used to connect a wired remote control that is used to switch the unit on and off and has a volume control knob. This is also finished in the same silky black matt coating. Both are good looking items and have prominent ‘Mutant’ branding upon them. It is supplied with fixings and feet and a manual sheet. This makes reference to use of the MT5AS in the boot but for all practical purposes, this is really a specialised under seat product.
– Frequency response: Not Quoted
– Power Amplifier 50w RMS (100w max) Says ‘200 Watts’ on the case, though.
– Five inch driver with 1 inch voice coil
– Input Sensitivity 200mV to 6.0V
– Die cast Aluminium enclosure chassis with cover panel over driver so could even be bandpass loaded
– Silky armoured finish in matt black
– RCA input and high level speaker wire input
– Wired remote control with on/off and gain functions
– Phase reverse switch, Crossover in/out switch
– Crossover adjustment from 80Hz to 200Hz
Review by Adam Rayner
Some of the more deeply involved bass heads who read Talk Audio Magazine, may find this item puzzling. In their world of woofers with four voice coils, each having two strapped three thousand watt amplifiers hooked up to them and sound pressure levels high enough to cause petechiae (capillary bleeding seen in the face and eyeballs of strangled corpses) the likes of this sort of thing seem to be piffle.
However, the under seat bass device remains a market that just won’t go away, with several also being available from the major Japanese companies. Of course, a single eight inch woofer with a 2 x 25 watt amplifier bridged into it and running in a nice box will outperform any of these devices when it comes to bass but there is one thing they really are hard put to do and that’s to fit under the seat. The Mercedes minibus thing has an eight inch woofer location under the driver’s seat that can have the OEM driver simply swapped out (You should have heard the INSANE three-eights install I heard in Vegas at the CES when Pioneer took me last year!) but for most of us, it’s a small space and kinda flat. And that’s where these things come in.
There can be many reasons why you’d want to avail yourself of such an item and one is simply to underpin without booming. A decent amount of any sort of lows can help the rest of your system sound bigger all round, not just in the bass. It can even improve the feel and shape of your front soundstage.
I hooked a Mutant MT7007DVD deck up to the Genesis Stereo 100 Amp through a posh JL Audio RCA and did the same with the MT5AS, using a rear line RCA output from the deck for it. I Played a dts demo disc. It has some clips from movies like Lord of the Rings and music from amongst others, Blue Man Group. There’s fat bass lines and in the Day After Tomorrow clip, the ocean inundates New York and it’s loud.
MT5AS really took some getting used to as I wanted to simply turn it all the way up and it wasn’t having it, sounding horrid. It can be made to unload quite easily and I even worried that the flat diaphragm rigid driver was a bit too close to the top cover it nestles beneath. I thought the suspension was rubbing and interfering with the bottom of it and had a feel. It is almost certainly not the case as the driver is not massively high excursion, but the distortion was high until I got it crossed over deeper towards the 80Hz point and then turned the rather wobbly-in-the-box gain knob-on-a-wire down a good bit. I experimented with the phase switch on the unit and found in my rig it was all in-phase and sounded best when left thus.
At first I wasn’t too bothered and was a bit underwhelmed but then, once set up so it didn’t gurk, I felt compelled to ‘Take It Out & Measure It’ as they say at AudioControl and fire up the SA-3055 Real Time Analyser (RTA) that I have had sent from the USA and it has become a ‘How did I live without one of these?’ thing in my professional life. Idly, I let it dance on RTA for a moment or two to see the blue LEDs (anniversary edition, yah!) reveal that it was tracking the bassline well and then flicked it to SPL and positioned the microphone a reasonably even distance between the B&W LM1 test monitors and the MT5AS front grille.
I found when switching the sub on and off with the remote that when playing at an average level of 85dB at the microphone on the LM1s, that when I hit the go button and got some fatness in there, it was up to around 105dB. And when I tried again, – as no matter how close-to-subjective the method was I wanted to make sure it was reproducible ( I believe in anechoism, honest!) and thus meaningful. I found on another track that when running to be around 80dB from the stereo speakers alone, it went to around 100dB when the bass kicked in. So although it is limited in performance and isn’t an SQ paragon, what it IS is a good value item for this application. I know of another from one of the Nipponese that costs a cool �90 more. It might be bigger in power and output but in every sector it is good t have a good, better best and for under seat woofers, this is the one labelled ‘Good’.
Sound Quality 6.0
Build Quality 7.0
Power Handling 5.0
Efficiency 7.0
Value For Money 8.0
Overall rating 6.6