A new model that builds on the same principles
used on all the other MJ Acoustics subs. Enter the Pro 55 Mk1 Subwoofer.

MJ Acoustics is world famous for their small miracle musical subs, but the Home Theatre (HT) guys wanted more “Bang” so MJ Acoustics was faced with the dilemma of how to build a HT sub that can still sounds musical as well. This is not and easy task because you need a different approach for each and this is not generally understood by the ‘man in the street’ or even by “reviewers” in Hifi magazines. It is understandable that some of these reviewers have a personal view of what products are good and what are bad. Many people also believe that this is driven by how much a company is prepared to spend on advertising in the magazine. Beware of these types of magazines. You can spot them easily; they do not back their reviews with scientific measurements and proof.

The problem is the uninformed ‘man in the street’ relies on these “experts” for guidance. A bad review can rob them from the opportunity to experience the products for themselves. A few years back we use to go and listen to the products ourselves and compare that to others in the market.  Not any more, it’s much easier to just “surf the net” for info. There in lies the danger: you rely on others (with their own personal taste) to make the decisions for you which can leave you unhappy.

A good example is the case of the new MJ Acoustic Pro 55 Mk1 Subwoofer: below is my first notes that I wrote for the importer and I later found a review in a British Hifi magazine “The world’s No 1 home entertainment magazine” (their slogan not mine). They reported some aspects completely different to what I have experienced. There were no scientific measurements  unlike some of the better known British and USA magazines. So I was very surprised how is this possible?

The debate of honest and unbiased reviews are as old as Hifi itself and it stuns me sometimes that cheaply made horrible sounding units get 5 stars and other well made units that use scientifically proven methods only get a few stars. Makes you wonder what value these reviews have other than trying to boost a cheaply made product of a big company with a huge advertising budget. Compared to well made honest products of small companies that try to make the best product they can for your money and using the advertising money to actually build a much better product.

Its scary how we rely too much on advertising rather than our own judgement, not only in what we buy, but also in what we do everyday – what we eat, even what we think. I am from the old school and do not buy into this. I use mostly commonsense and then further study aspects of these senses to help me in making informed decisions on what is important for me and what is not. The end result is far more enjoyable than just having something that another guy told you to have. So let us revisit the commonsense and scientific principles of what is important in choosing a sub for music and/or home theatre? This is covered in our Subwoofer FAQ’s, but I thought I’d repeat it here as it seems appropriate.

To get the best advice in life you have to go to a specialist. If you are feeling ill you go to a doctor but if you are really sick, or need an operation, you have to go to specialist. A specialist is just that: a specialist in his area of expertise.  So is it with everything in life, if you need the best bed you go to a bed specialist store. If you need the best sub you must go for a specialist sub builder. There are only a handful of these companies in the world today that can be called a sub building specialist, MJ Acoustics is one of them.

The following 6 principles can guide you in making a choice for the right sub for your needs.

1. Build Quality:  The best subwoofers are the ones that are designed and manufactured in their home country, ideally in their own factories, with their own dedicated staff, not in a far off country were they pay the poor workers peanuts and expect them to be proud of their work, it will not happen… ever.

2. Brand Pedigree: The brand must also have a “pedigree”, that is it must stood the test of time.

3. Driver Size: The simple key to produce more bass is” The bigger the driver the better and the quality go hand in hand with the weight of the sub.  The basic physics of bass sound is to move air at low frequencies. The more air you want to move (for good bass) the bigger the driver you need. To design a good small sub is a very challenging engineering job and a hot topic nowadays, but its not easy and its expensive.

4. Design Principles:  There are basically 3 types of sub designs:

• TYPE 1 – Bass driver inside the cabinet and the only bass that comes out are from a port. They are the worst sounding subs with a “hollow, drooney, tube like” bass sound. Remember when you were a kid you talked into a tube to lower your voice. Well that is the same principle used here. This type is used by the mass market “all in one sub/sat sets” from Sony, Panasonic, Pioneer, JVC, Bose etc. because it’s cheap to make, you only need cheap small drivers  6″ that do not need to move a lot of air to fake “bass” sounds. DO NOT WASTE YOUR MONEY ON THESE TYPES of SUBS

• TYPE 2 – Bass Reflex – This design is mainly used for  Home theatre (HT) subs. HT basically  consists of a lot of dialog, high frequency effects and lots of “distortion” in the bass frequencies. That is why bass quantity (volume) is far more important than quality and for that you need a big sub woofer and to increase bass volume a bass port is also used to push air out – the so called bass reflex design. However, you introduce distortion (typically 10% to 20%) and also port noise. This is not critical for HT which is distortion and noise in any case at the low frequencies. The advantage of the bass reflex design is that you can build these subs much cheaper, with cheaper cabinets, cheaper drivers and cheaper amplifiers.

• TYPE 3 – Sealed Enclosure – For music, the bass reflex design and big subs is not ideal, in fact nearly the opposite is needed: you need a well designed small sub with accurate bass and less distortion and no port noise. Bass reproduction for music is very important (turn the bass control on your amp completely down and listen how the scale of the music disappears). However “lots” of bass can tire you out very quickly, especially when it drones. Quality bass is far more important, the bass must be tight, well defined and must have bass weight. The best music subs are from the sealed enclosure type (not bass reflex). Sealed subs generally goes lower and have less distortion than bass reflex subs and do not have the dreaded port noise. Sealed subs are expensive to make because the sub’s amp needs to be at least 3x more powerful to drive the driver against the trapped air inside the sealed box. The cabinet must also be made super strong to have no vibrations of its own. That is why the best and most expensive sub from major sub builders in the world use subs of the sealed enclosure type

5. Driver Placement: Another important factor is the placement of the driver. These are very heavy units with huge magnets and it makes sense to fit them in a down-firing way to support themselves. This also has the added advantage of using nature own force, the gravitational force, to help pull the driver down on the start and damp it on the backward movement. This is Ideal for a fast tight bass without the dreaded overhang. It also remove the necessity to turn  your big driver (on front firing subs) every few years at 180 degrees to compensate for the dragging  force on the driver’s rubber surround and voice coil.  The driver also fires at right angles to the main speaker’s drivers making correct phasing and placement in the room less critical.

Now let us see how the MJ Acoustics PRO 55 MK1 sub fits against the above principles.

1. Build Quality: Its 100% designed and built in England.
2. Brand Pedigree: MJ Acoustics have probably won more awards for each of their subs than any other.
3. Driver Size: This is a 12″ driver only beaten by a few 15″ drivers and its big brother the Ref 800 with an 18″ driver
4. Design Principles: Sealed enclosure, the best
5. Driver Placement: Down firing – Yes

So, it ticks all the boxes… the question then “Is the MJ Acoustics Pro 55 Mk1 a ‘Best of both worlds’ sub suitable for Music and HT?”

This is my notes I wrote the John, the NZ importer of MJ Acoustics subs, when I first auditioned this sub.

Hi John,

I now had the opportunity to listen to this new model. What and interesting and very enjoyable day! My immediate thought was – this is good stuff!

I listened to the new Pro 50 Mk1 first as a musical sub with my ProAc Reference 8 small bookshelf speakers, again I heard the same unmistakably unique MJ Acoustic characteristic sound that underpins all MJ Acoustics subs this really separates all of them from the rest of the subs from other brands… clean, tight, fast bass with slam and bass weight, yet still able to reproduce subtlety and detail. The Pro 55 mk1 has heaps more of everything! even at low volumes. As the volume is turned up, the Pro 55 mk1 continues to shine… it just keeps getting louder, yet the sound still remains tight, detailed and controlled, even at very loud levels…fantastic! Why do you need big floor-stander speakers and big amps at huge cost to drive them if you can get the same, no better! With this combo at a 1/10 of the price?

“But wait there is more!” I took the Pro 55 Mk1 down to the home theatre room and invited my wife to come and listen as well (we love to listen to live recorded musical DVD’s). I set it up basically using the same settings as for music and we started the show… we looked at each other and I could see the disbelief in her eyes, we were shocked! We know that track so well, yet we were hearing bass detail that we have never heard before. I turned its volume up another notch and the power and massiveness of the bass thumped at our chests… we heard things like double bass… different types of bass… different types of slam… totally separate of one another… not a single rumble of all instruments stuffed together like with most subs. I turned up the main volume of my AVR and we sat back and listened track after track, we could not stop; we did not want to turn the volume down because it was all sheer enjoyment and when it all stopped, we felt a bit disappointed and a few seconds later I realised what it was… we wanted an encore!

I only ever heard this quality of bass with my $4000 Jamo D6, $5500 Paradigm Servo 15  (both 15″ bass drivers at many times the power) & the bigger MJ models… The MJ Acoustics Pro 55 Mk1 must be the best bargain in Subwoofer History! Suitable for both Music and Home Theatre… how does the saying go? “Yes MJ.. Has done it again”.