- Written by Carlo Lo Raso
- Published on 12 March 2014
The Design of the GoldenEar Triton Seven Home Theater Speaker System
In discussing the Triton Seven's development with Sandy Gross, he made it clear that in order to get this model made at the price point that they wanted; the design team knew that they had to forgo some of the complexity and expense of the powered bass drivers used in the pricier Triton Two and Three models. So (paraphrasing here) they started with a clean sheet of paper and concentrated on the basics of tried and true speaker design, refining the details, taking the time and using the technology in the smartest and most resourceful manner in order to achieve their goal.
The Triton Sevens themselves are a rather elegant looking pair of speakers. They are of a modest height, barely reaching my waist when I stand beside them. They have a thinner width in front and are wider in back giving the speakers a wedge shaped cross section. That shape, combined with having a larger base area and a smaller slanted top means that none of the speaker's surfaces are parallel to each other. This along with having a gentle swept back rake to their design (intentional for aiming the sound of the tweeters to arrive at your ear level) makes for a very striking look. The towers are covered with a black fabric "sock" which is not meant to be removed, save for a service technician. The fabric is meant to provide extra damping to the speakers and, working in conjunction with the narrow front baffle, results in what GoldenEar calls "The Seven's precise and totally box-less image characteristics."
The Triton Seven's main driver compliment consists of a rather interesting High-Velocity Folded Ribbon Tweeter placed between a pair of 5.25" mid/bass drivers. This is commonly referred to as an MTM design or D'Appolito array named after its initial developer, Joseph D'Appolito. The internal pressure created by the mid/bass drivers during their operation is channeled to the base of the speaker where it couples with and excites the two opposing 8" passive radiators. These radiators exist in place of more commonly seen tuned ports and help to create what is essentially a fully sealed speaker design with unexpectedly robust and accurate bass reproduction.
The High-Velocity Folded Ribbon Tweeter or HVFR™ as it is named by GoldenEar, is similar in design to an Air Motion Transformer or Heil type tweeter. What are the benefits of such a driver you may ask? Well, whereas a more common dome or ribbon tweeter projects it's sound by vibrating a diaphragm back and forth, the HVFR™ looks and acts more like an accordion, pressurizing the surrounding air and launching the sound out at an extremely fast speed. The folded design of the diaphragm means it has more surface area and that subsequently more air can be moved than a competing dome or electrostatic tweeter of the same size. The increased surface area allows the accordion's movements to be very small to move a given amount of air, resulting in inherently low driver distortion. While originally developed in the early 70s and used on some high end speakers of the day, these types of drivers are still not in widespread use currently, although some manufacturers like Emotiva and Legacy are incorporating them in some of their offerings. In general, this driver type is said to require great care and attention to both cabinet and crossover design to achieve the best results. Obviously GoldenEar must feel like they are on to something good here, as they use the HVFR™ across their entire speaker line.
The 5.25" mid/bass drivers are also unique to the Triton Sevens. These rigid cast basket drivers were custom engineered to work in tandem with the twin passive radiators. These drivers were developed to have an extra-long throw without generating any additional distortion and they use no phase plugs to ensure that the Triton Sevens remain completely sealed so that the passive radiators can operate effectively.
The 8" passive radiators are installed in an opposing configuration at the base of the Tritons Sevens to help cancel out any unwanted vibrations while they operate. In its simplest form, a passive radiator is like a speaker driver without a magnet and motor assembly. It's a precisely weighted membrane that is excited by the internal forces in the speaker cabinet generated by the other drivers, usually a bass or a mid/bass driver. Passive radiators can be used in place of tuned ports in speaker or subwoofer designs to help generate the lower frequencies. The advantages being that sometimes ported speakers can exhibit "chuffing" sounds as air exits the port. Passive radiators generate no such unwanted noises and they can also be used in smaller speaker and subwoofer designs where longer tuned ports would be impractical to use.
The main downside to passive radiators is that it is more expensive and complicated to design such a system over a similar one using a tuned port. Sandy described the interaction between the mid/bass drivers and the passive radiators this way: "I had a discussion with Bob Johnston, our head of engineering, to go over the bass loading in more detail, as it seems to have worked out extremely well. He told me that they worked 3 months on getting it right. Basically, it has what I am going to call, Frequency Differentiated Damping or FDD. What Bob explained to me is that the cabinet has a fairly dense fill of a special hollow polyester fiber in a very specific configuration (less fill behind the upper driver, quite dense down to just above the passives, which have no damping between them and then damping at the bottom of the cabinet). This functions much like a well damped transmission line down to about 80 Hz (which loads and controls the drivers really well) and then becomes much more acoustically transparent below 80 Hz. This allows virtually all the internal bass energy generated by the 5.25" drivers inside the box to be effectively coupled to the two 8" passives down on the bottom on the sides where they effectively couple the bass energy to the room. Also, since they are opposite each other, their inertia is effectively cancelled, which we call "Inertially Balanced". I think this is another example of utilizing and incorporating technology which has clear acoustic benefits which doesn't necessarily cost more to do (well actually the fiber is relatively expensive, but not crazy) but just requires knowledge, experience, time and caring to get it right. Basically a hallmark and cornerstone of what we do."
Moving on to the accompanying speakers, both the SuperCenter XL and the SuperSat 3 share the same HVFR™ tweeters as the Triton Sevens. They also share the same type of High-Definition Cast-Basket Mid/Bass Drivers with Multi-Vaned Phase plugs, 5.25" diameter on the center speaker and 4.5" diameter on the satellites respectively. The center speaker also has a pair of oblong shaped passive radiators on its top side, again like the idea on the main speakers, these are meant to extend the low frequency reproduction beyond what you might expect of from a speaker of this size. Like the Triton Sevens, it also wears a matching non-removable fabric covering and is finished with glossy black end caps on either side.
I was initially concerned that the SuperCenter's driver layout may limit placement flexibility for some users as you'd want to keep some measure of breathing room around the passive radiators up top. However, Sandy indicated that: "In reality, the center channel only needs a couple (2) inches of clearance, as what is coming out is actually a very low frequency pressure wave and the added slot loading (from an AV rack shelf) actually improves things slightly, rather than causing any problems or boominess."
The SuperSat 3's design is very stylish and svelte at only 2.7" deep and 12" tall. These speakers feel very solid when you hold them in your hands. I originally mistook them for all metal or aluminum construction, but according to GoldenEar's literature, they are in fact made from "a rigid, non-resonant marble powder infused polymer." They also come with easily removable curved magnetic grilles and both a small bracket, which acts as a stand for shelf placement, and built in keyholes for wall mounting.
The ForceField 5 subwoofer is a stout looking little affair. Comfortably sized at roughly 15" wide by 18" deep by 14.5" high, it wears four rather large (palm sized) nubby-rubber isolation feet on its underside. Jammed inside this small trapezoidal package is a full on 12" long-throw subwoofer driver mounted in front, a 13" by 19" oblong passive radiator in the bottom and a built in digital amplifier rated at 1500 watts.
Weighing in at 46 pounds, the ForceField 5 feels very dense, both when you rap your knuckles on the cabinet and try to it pick up. The user controls are fairly standard for a powered subwoofer. There is a Low Pass Frequency dial, a Gain dial, an LFE input jack and High Level Inputs and Outputs. There is also no on/off toggle switch as this little guy is strictly auto signal sensing.
I personally wish there was some sort of parametric EQ feature, even just a single band. While I know auto room correction systems in most modern AV receivers take care of a lot of room issues when properly implemented, they can't always tame every dip or peak in every room. If you're the kind of person who likes to tweak your settings (guilty!) and go through the extra effort, it's nice to have this little extra measure of adjustment for difficult rooms or if your subwoofer placement options are limited. Go to Page 3: Setup