VMPS NEW LARGER SUB
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What is it?
A passive subwoofer consisting of a 12" and 15" active driver with a 15" mass-tuned/slot loaded passive radiator.
I hope I can write this so it communicates sincerely. There is a fine line between enthusiastic and being a fan boy. I am a healthy skeptic. I have been away from 2-channel listening (except for armature-type earphones) for many years. I no longer have a lot of the original hyper expensive high end gear I accumulated in the 90’s and early 00. I will say that I have been on a DIY and modding tear for the past few months. I am developing a 2-channel music rig that isn’t going to have the huge overhead costs. As weird as it sound, in this economy I am attempting to make a 2-channel music system that isn’t a money pit. I tend to keep gear now, no more of the quarterly or semi-annual “upgrades.”
Soapbox:
There is no replacement for displacement. If you are talking street performance or subwoofers, it’s all about moving air mass. In a medium large to large listening area, I have yet to really enjoy a small sub. I have been recommended powered subs that sounded musical, but not particularly potent. Don’t even get me started on those home theater ported subs that rattle things with globs of 80hz energy but taper to nothing in the 30’s. Those are truly Satan’s handiwork. They are a demonic plague foisted on fidelity-loving humanity; much like Bose and Mp3’s. I have a word for a transducer that reproduces audio down to 30hz and tapers off. I like to refer to them as a “woofers.” The term “SUB” doesn’t apply. I have heard the argument that 15” and 18” drivers are sloppy. Cheap drivers with a weak motor certainly are. Stuffing a big sub into a small room will do it too. Why use them in a room that won’t support low bass? A 15” sub in a 10x12 room? Please.
I subscribe to the philosophy of parts express Dayton titanic sub kits. In many subs under a grand (or more), you are getting an abysmally cheap driver. I can’t argue with that because I have heard too many examples that bear this out. (Anyone remember Radio Shack subs? I shudder at the thought.) I hate it when subs bottom out easily trying to keep up: that horrible rattling and clicking during a Mussorgsky piece. “SUBS” have found their way into homes that don’t even use them as subs. Listening to mp3’s or movie explosions isn’t a test of a music sub. It’s more of a test of compressed but heavy mid bass and personal tolerance to noise. It seems like when I hear subs mentioned in conversation, it’s usually about car subwoofers, or the aforementioned HT subs. I wanted orchestral deep bass with 20hz fundamentals, not passing off mid bass as low bass. Ideally, this would bring a proper sense of scale with an equivalent SPL. Yes, I have tried 12” “tube” subs in the past. They work for some things, but don’t have the same impact effect, for example as a forward firing 15” Velodyne. I prefer the boxed sub like the high end Velodynes, just can’t justify the expense right now-especially the 18” model. Hell, maybe I am nuts right now for thinking I needed to spend $1,200 on a new sub. Or maybe, I just miss bass quality and quantity bad enough to rationalize buying the VMPS.
My order
I do remember the original larger sub, it was a vertical sub, with the 12” driver above the 15” active. The reviews have all been excellent and part of the reason I went this route. The new larger sub has a “lowboy” horizontal configuration with the active drivers side by side. I opted for light oak, because the cabinet is going to get a new finish (red chestnut-see pic) and a clear coat to match my refinished speakers. After talking with the John “bioforce” Casler (Summit Audio here in the forum) about options, I requested the carbon fiber megawoofer which is a $140.00 upgrade. I agreed it was best that I went with external amplification. It can’t be good for anything electronic (like a plate amp) to get shaken brutally while attached to a big sub. The plate amp is one of the weaknesses of my DIY sub. For use in my HT system, it’s not that vital.
Unpacking and setup.
The amp and the sub base frame arrived day 1. I was hoping the sub was there too, it was not to be. With that “teenager watching a twilight movie” glee, I finally got the big, heavy box from the driver hand-dollied into my garage. My first step was to unbox and inspect, and then immediately work on it’s new finish. I had every intent of going out and enjoying the sunny day while it dried. I also prepared some audioquest IC’s and speaker cable.
The subwoofer amp: (from the VMPS instructions)
Thank you for purchasing the VMPS 1000w subwoofer amplifier, one of the most versatile and powerful subwoofer amplifiers available. The tabletop or rack-mountable design is perfect for all VMPS Model Subs and high-end home theater and Audiophile apps. With 1,000 clean watts of power into 4 ohms, it can drive ALL our subwoofer systems.
It’s a Dayton audio SA1000 class a/b sub amp.
I prepped my amp eq by the following instructions posted by Brian Cheney:
“When you get your amp please notice the "EQ" section which should be used to notch out the floor-to-ceiling room mode that does not yield to placement or other remedies.
Measure your ceiling height, which will tell you what mode frequency to cut. Using a Q=0.25 cut the following frequencies by 3 to 4 dB:
8ft ceiling 71Hz
9ft ceiling 63Hz
10ft ceiling 56Hz
Also be sure to do "putty pinching" as per the instructions here. This will trim system Q to your equipment, speaker wire, and associated equipment. A fingernail full of putty at a time removed from the center of the PR is all you want. Go slowly.
If your ceiling is taller than 10 ft simply divide the number 565 by its measured maximum height, then cut that frequency.
Example: 12ft ceiling = 47Hz.”
I measured the room, and set up accordingly. The extreme versatility here is that I am not just using electronic bass management, but I can also use physical bass management by adjusting the passive radiators mass damping putty by a few grams here or there. This sub is not relying on a servo (which as you can read elsewhere-aren’t the solution for every bass situation) or electronics alone. This sub takes a little more tweaking, but as a result will give you more of a tuning and damping range. Since my floor is concrete...it means less fiddling, and less room structural excitement.
A few comparisons:
The parts express Dayton titanic sub kits do outperform the HT subs out there for music, and tend to be pretty close to the best of them for HT. For music against a music sub, that’s a different story.
I like to classify the ability of subs in these categories: 1) Incapable of significant 1st octave bass (many HT or small subs) 2) Presence of 1st octave bass, but with compromises 3) Strong of 1st octave bass, but with compromises 4) Presence of 1st octave bass with significant quality, but not superior energy 5.) 1st octave bass with significantly powerful impact and high quality. The 12” Dayton is a category 2. The 15” Dayton is a category 3. The Hsu and REL strata are category 4. They have quality, decent power (but not massive air-moving slam in the lowest reaches). I started with Nikolai Andreyevich Rimsky-Korsakov’s Scheherazade” and John Ottman’s soundtrack to “Superman returns.” That was enough to determine the limitations of the 12 and 15” Dayton titanic III kit subs. Those subs ship with a class G (500w) and class D (1000w) on board plate amp respectively. Here is the bottom line: The 12” sub was adequate to provide deep bass presence, but not heft. It was obvious these recordings had low bass energy in parts, but there was a unfocused quality, much like an HT movie explosion. The 15” Dayton titanic kit had significantly greater low end and great slam. The same problem existed though. For music like this, the focus/definition was lacking. I can rightfully classify these subs as fine for 80% HT, 20% music, but cannot say these subs hold up to critical listening. Surprisingly, my Hsu TN1220HO sub had better definition than either sub, but lacked the impact of the forward firing 15” Dayton kit sub. The HSU has its own rack-type amp. The Hsu sounded like it filled in the bottom, but didn’t communicate it with that huge body-punch effect of good box subs. The REL strata III was wonderfully musical, and was in between the 12” and 15” Dayton in terms of heft, albeit with better definition. Great music sub, but not the seismic generator I am after. I cannot recommend the Dayton titanic for use in high end audio. It just won’t match the definition of top notch main speakers.
Dialing it in.
I was instructed to remove bits of damping putty from the passive radiator in the “fingernail” full. That is, about 1-2 grams at a time. I ended up removing about 4 fingernails full. I ended up setting the sub amp to cutoff sharply at 60hz. Rule #1 I learned in the 80’s: Never start with synthesizer bass, because you have no real frame of reference as to how it’s really supposed to sound. I have medium carpet over concrete in my listening room, so unlike some environments, I don’t have a lot of sympathetic noise from the room. The concrete is pretty good at reflecting the bass and not rumbling with it. This simply gives me cleaner bass than is possible in my upstairs HT room.
Mjolnir. You know how the output is listed for tube subs (HSU/SVS) and things like REL strata? They might as well take the back seat. The amount of air they move and impact is considerably less compared to this sub. This sub is Mjolnir: Thor’s hammer. It has output similar to an 18”, 4 grand Velodyne sub. “Thou shalt be moved” This sub has overwhelming power compared to even my 15”/1000 watt Dayton titanic III sealed box sub. It has the ability to unleash orchestral bass that would scare those HT subs out of the house. Here is where I separate from the small two way only or any bass limited system Realism, to me is palapable, 1st octave bass. Without it, there is no way to sound like a live drum kit or electric bass because small or bass limited speakers just don’t produce the same energy as the real thing. You should not expect the same flabby, boomy midbass you get from HT subs. At first you may think “feh” in some circumstances, yet when the recording calls for it---the concrete floor shakes and the air is energized.
The very definition of bass.
It has musical definition like the REL strat, a smaller and highly rated sub.You know the sub is blending, and in the zone when it doesn't load the room up with 2nd octave and duplicate the main speakers. The sub should be defined and sensitive enough to tackle guitar strings, yet brutal enough to reproduce cannon shots , organ notes and other 1st octave energy with the same alacrity. I am getting a realistic, palpable attack and body from the guitar strings on "Man of constant sorrow" (O brother where art thou) and symphonic weight from telarc's "space spectacular." Listen to the opening of Star Trek: the motion picture of Battlestar galactica theme. That is some potent bass. Don’t expect every orchestral bit to have massive low end because some recordings just don’t have it to begin with. For example, as good as Basil Pouldaris “Anvil of crom” is, it doesn’t have the same energy as a telarc recording of Mussogsky: night on bald mountain/pictures at an exhibition. The best of Tony Williams: drums sound like drums. The punch, the low end, the presence. Not possible without a serious 1st octave output.
EPILOGUE:As good as the original tallboy was (Reviewed back in the day by Bert Whyte), the lowboy has better drivers, now, even better than the carbon fiber drivers offered before. There is a storm coming. No, not the new Thor movie, but that’s cool too. What I am referring to is the OMG series new larger sub that includes the un-freaking-believably omnipotent TC sounds drivers. Those drivers will be able to deliver subsonics powerful enough to recreate a REAL subway going though your listening room. When I get the scratch, I really want to upgrade. Much like Thor’s hammer, TC sounds drivers have the potential to crack the earths crust. In the meantime, I am happy with a sub that won’t just hang in there with the huge, megabuck velodynes, it does it for a fraction of the price. The Dayton titanic may separate the dreck from the high end, the VMPS new larger sub separates real performance from high end toys. Stay out of the boutiques, and you don’t need a servo sub or to spend several grand. This sub does it all and it cost me all of $1,200 shipped with an amp. Spending 3 times as much won’t improve anything. However, buy one or two of the OMG subs and you will be playing with something that dwarfs Velodyne, and still spend less than one Velodyne. Note the cost of Velodynes top end 18” sub. Now look at a TC-sounds equipped very large array sub from VMPS. No contest! The Velodyne hasn’t just met its match, it’s now not the most capable sub for under 10 grand.
Recommended subwoofer tests:
Telarc: space spectacular
Time/Life classical thunder (telarc)
Rob Wasserman: solo
Enya: greatest hits
James Horner: Titanic soundtrack
Basil Pouldaris: Conan the barbarian soundtrack
Andreas Vollenweider: various
Bela Fleck and the Flecktones: flight of the cosmic hippo
Al Dimeola: Kiss my Axe
Crystal method: Vegas
Propellerheads: decksanddrumsandrockandroll