MartinLogan Depth i Review
Over the last couple of months I have been enjoying the company of a new subwoofer by MartinLogan, a company famous for their electrostatic speakers, and superlative they are with a few people here who own them. I know of a couple of staff members who use MartinLogan speakers and that is what got me thinking about the two subwoofer offerings from MartinLogan, which are the Depth i and Descent i. Both are unique in that they feature three drive units, three 8" drivers for the Depth i and three 10" drivers for the Descent i, versus the one or two driver arrays that are typically used in other sub designs. The MartinLogan Depth i comes in at roughly £2000 here in the UK and about the same in U.S. dollars.
I have had my fair share of commercial subwoofers over the years, ranging from low end to high end with offerings from the likes of Rel, BK, Velodyne and M&K. The M&K being a hard act to follow due to its high SPL and quite spectacular movie performance. The Velodyne subs I had were dual DD12's, which were no competition for the M&K for both movies and music, but still good subs none the less. The Velodyne DD models have just recently been updated to the DD+ version.
Design, Connections and Setup
The first thing that struck me was the weight of this sub, coming in at approx 32Kg, although it sure seemed to be heavier. It is built to the highest of standards and looks very nice for a subwoofer with three drivers. This is a patented technology by MartinLogan using their TriLinear Driver Array and BalancedForce Driver Alignment. The Depth i locates the three drivers of its TriLinear array precisely 120 degrees apart on the cabinet. Each driver unit is also servo controlled so that the signal is kept intact and distortion kept to a minimum. This design has recently been seen in the new Paradigm SUB 1 and SUB 2, except with six drivers per cabinet.
Connections and setup was a breeze with all the dials for Gain and Crossovers being accessible on top of the sub and covered by a solid aluminum plate. There is also a PEQ for the lower frequencies in the 25-30Hz range to help in room correction.
Connections are via RCA and speaker terminals depending on how you are using the sub. It also has inputs and outputs for daisy chaining the subs if you want to really beef up the bass and use more than one sub, the only connection missing is Balanced inputs which may be a problem if long runs are required, although they are available on Descent i sub.
My connections only require 1M RCA leads. It sits just inside my left speaker, which has always been the best location for all my subs.
Sound for Movies
Recently movies have not played a major part in my listening and viewing sessions, at least not since our daughter was born. Late night viewing is kept to a minimum, but during the day I can let it rip and get the SPL levels up quite a bit.
The usual material I have for demonstrating movies and my systems performance have become quite common because they have excellent mixes and soundtracks. I have become very familiar with them on quite a few systems, although my memory is getting a tad worse as the years fly by.
For demonstration purposes I used War of the Worlds, Minority Report and Flight of the Phoenix. Most of you will know these films fairly well. I suspect you have watched the machines coming out of the ground in War of the Worlds many times over. The Depth i did not disappoint in any way at all, with plenty of slam and movement of air. I was actually not expecting the performance to even come close to my previous sub, but it went very low and with no audible distortion. The volume was around -10db below reference, which was loud enough and very enjoyable.
Minority Report was pretty much the same with plenty of bass in the car factory scene. It pressurized my room quite nicely, with the car seat coming down creating a nice bit of slam and punch to finish off Mr. Cruise (not sure how he escaped that one).
Flight of the Phoenix has an excellent soundtrack in DTS HD MA. The Depth i handled the storm/crash scene with ease and brought justice to the excellent sound mix, keeping me on the edge of my seat. Obviously over the last few months I have watched many films, but the ones demonstrated stand out quite well and separate the men from the boys when it comes to subs. It has delighted me on many soundtracks. With it being so compact it matches my kit extremely well and even my partner said, "Thankfully no more big black boxes". She has given it the seal of approval and it is most certainly staying put.
Sound For Music
This was the most important reason I wanted this sub. I had just purchased some new ProAc D28's and for music they are sublime with a gorgeous mid range and top end, but also with a powerful bottom end. For a 2-way floor stander they surprised me and made me wonder if I really needed a subwoofer at one point. I decided I would look for a sub with the quality of bass that could match the 28's and then some, but most importantly integrate seamlessly, of which the Depth i does with ease.
I have always been the type of person who is against using a subwoofer for 2-channel music and believe in keeping the sound as pure as possible with no sub. I typically use the ProAc's in direct mode from the Arcam AV888. My Arcam processor is the only processor I have came across that plays 2-channel so well and also does movies justice. When partnered with my ProAcs and Martin Logan Depth i, there certainly seems to be a synergy going on with the Depth i complementing my D28's perfectly.
I love all sorts of music with Jazz probably being my favorite. Acoustic Alchemy has made some excellent albums, of which I own them all. Another favorite is Claire Martin with the combo of sub and speakers bringing out the best in their music. I recently purchased the soundtrack to the remake of the TRON film, which is performed by Daft Punk and has some low bass to test your subs abilities.
What I like about the Depth i is that the smaller 8" drive units are very punchy and dynamic, matching the performance of my speakers. The bass is very rich and deep, with a texture to it that lesser subs cannot match. The Depth i easily beats my previous M&K sub for music.
As you can tell this sub is certainly firmly rooted into my system with an excellent sound. It has deep rich bass that will certainly keep any audiophile content. I personally recommend an audition if you are looking for a compact and quality performing subwoofer for your room.
The sub was supplied by Guildford Audio which offered an excellent service and come highly recommended
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