TRIANGLE ▻ Delta Signature

Triangle’s Signature Series was launched in 2013. Replacing the Genesis series, it is now a double hinge between the Magellan and Esprit EZ, on a technical but also economic level, which brings the Magellan’s flagship technologies to more accessible models.

Four speakers are listed within the Signature family, two Alpha and Delta columns (which we are going to present to you), a compact Theta and a Gamma centre channel which symbolises the universality of sound and image use of this range.

The three-way, four-speaker Delta column was the basis of the Signature range. This combination is commonplace with the manufacturer, which in other words means that it is perfectly mastered. The implementation takes up recurring themes for the brand, namely a bass supported by two boomers, a midrange reproduced by a paper cone speaker, a material Triangle has been using since the creation of the brand, and a semi-dome tweeter loaded by a front horn. The cabinetwork has benefited from the attention already paid to the Magellan’s bodywork. It is made from seven 3mm thick HDF (High Density Fiberboard) panels that are assembled and then bent under press. The total thickness thus reaches 21 mm for all the walls… except for the baffle support which is 25 mm thick to make the loudspeaker heavier, perfect the mechanical reference of the speakers and improve stability. The finish is luxurious with a total of ten coats of paint. Between each coat, a manual polishing is carried out before obtaining a surface with a piano lacquer finish. Three gloss finishes are available, white, black and mahogany veneer. The bass reflex loader used for the low register employs a Twin Vent front port that is inserted between the two boomers. This dual-conduit vent channels the rear wave from each bass driver mounted in an independent volume, reducing intermodulation between drivers and distortion of the register.

The two 165 mm boomers have a fibreglass membrane stiffened by a second paper cone suspended by an inverted rubber half roll from an injected aluminium bowl. The profile of this membrane has been studied by computer tools for a specific use in the bass. With a central aluminium core cover, the rigidity and lightness give the loudspeaker an excellent acceleration power up to the high cut-off fixed at 280 Hz. The double-layer voice coil and double ferrite coating provide high power handling and sensitivity. The 165mm midrange uses the same bowl as the boomers, a model designed for the Signature range. The rear clearance ensures no compression and good ventilation of the double-layer coil. The profile of the treated paper diaphragm has been redesigned for better dispersion. There is a low travel suspension made of small-pleated fabric, a tradition at Triangle. An ogive-shaped core cover replaces the usual solid ogive, a more airtight method that prevents air leakage when a loudspeaker is mounted under closed load. This is the case with the Delta midrange, which emits up to 2700 Hz. The tweeter is none other than the famous TZ2500 whose phase piece has been redesigned for the 25mm titanium dome. The new die-cast aluminium horn is a variation of the Magellan program. Its larger «active» surface guarantees a better dispersion of the high frequencies. The volume of the rear chamber has been increased in order to obtain better damping and to avoid the return of rear waves to the dome, which translates into more precision, finesse and transparency of detail and a much lower level of distortion when listening. The tweeter is mounted in a half-cuffed slot at the top of the Delta. It largely gets rid of the possible vibrational effects of cabinetry and possible cabinet diffractions.

Filtering corroborates the improved performance of the speakers. As a result and by a judicious choice of the transition frequencies, the quantity of components in each section has been reduced for greater fidelity. The inductive components used in the low and mid frequency ranges have been oriented to avoid magnetic coupling. The double terminal block for bi-wiring or bi-amplification uses four copper alloy plugs designed and manufactured by Triangle. The internal wiring is made of Kimber Kable «multistrand» (several conductors of different cross-sections) selected independently for bass and treble. Finally, the Delta is based on a base with an improved SPEC II (Single Point Energy Conductor) spike system. The die-cast metal base beneath the Delta rests on two spikes at the rear of the speaker, while a solid polished steel cone on a cup is positioned directly underneath the baffle support. Similar to the point of support of a cello, this cone evacuates a large part of the mechanical energy to the floor. The vibrations of the cabinetwork are immediately eliminated and their influence on the sound is infinitesimal.

Directivity curves 0, 15°, 30°, 45°. 
Excellent directionality, not very pronounced and perfectly regular off the mid-axis, on the horizontal plane. The decoupling of the horn tweeter above the cabinet limits the effects of edge reflections. Combined with the exponential profile of the midrange, these elements are conducive to the stability of the stereo image as well as perfect spatialization.
Impedance versus frequency curve.
Profile of a three-way bass-reflex system tuned around 35 Hz. Module with
a nominal impedance of 8 Ω and a minimum of 3 Ω at 115 Hz. In view of
its efficiency and the amplitudes of the impedance variations, it should not
cause any notable problems for the electronics.
Curve per third of an octave in the axis.
Good linearity of the response curve. The progressive attenuation of the low frequencies gives it a pleasant feeling of «non-overbidding» of the low frequencies, free of any distortion. Good sensitivity of 92 dB at 1 m at 2.83 V.
Waterfall curves.
Very fast overall damping. The two independently tuned loads provide
excellent damping and greatly improve transient accuracy.

The Delta are imposing columns that need to breathe, and therefore need a minimum of living space. At less than 20 square meters, the game is not won! Moreover, as they give off a very beautiful energy, they will not be able to accommodate the angles of a room, and if the proximity of the back wall (30 cm minimum all the same), is not a problem, it will be necessary to take care to move them away from the side walls. We have observed a slight focusing in order to make the sound scene more precise. Even though the 92 dB output is quite favourable and the Delta’s are quite easy to load, it is still true that they encourage «live» level listening. A well-dimensioned built-in will therefore be welcome to drive them: a Hegel H190, a Devialet Expert 140, or a Primare I35 will be quite appropriate. Even a «tube» with a sufficient power reserve… Ultimate precaution: the speaker terminals are hyper-qualitative, but the jumpers (as on 99% of the speakers) will preferably be «forgotten» and replaced by pieces of good quality stripped speaker cable, or even better, good quality branded jumpers.

These lush columns are not what you think they are. If their flattering aesthetics might lead you to think that they will embellish or even overload the sound message, you’ve given in to the ease of facial offense. In fact, Delta speakers are much more mature, neutral and subtle than that. We started our tests by trying out different connecting cables in order to achieve the best tonal balance and optimize the sound experience. We were struck by the precision with which the Delta’s highlighted the differences between each type of cord. If you think you’re detecting an imbalance in your listening, don’t blame the Delta’s, but rather check its chain mates: the problem will undoubtedly come from them. Triangle columns deliver a great, beautiful sound, pure and authentic. The bandwidth is wide, with a luminous treble that rises high with a lot of energy but without any unpleasant tonic. It offers the good sides of the compression chamber, and less its faults: excellent! The middle register is very open, expressive, capable of reproducing the feeling of flesh without affectation, but with delicacy. As for the low register, it is tense, tonic and fast. On a double bass, it underlines all the finesse of the melodic line, but does not force the flattering effect. On an extract of modern music, it supports the message, accompanies the line, but doesn’t make you feel full of it. That said, if your amplifier is doing its job properly, this beautiful column will not bring you any frustration, because the bass descends low and level. The sound stage is particularly pleasing because it offers a wide, well-spaced panorama. The structure of the picture is excellent, and the sound planes drawn with care. At times the Delta seems to push back the walls and emancipate itself from the physical boundaries of the room, so much so that it reproduces an airy and credible space. Transparency, balance, spatialization, but also dynamic, as the Delta’s master the rhythms with brio. On a simple or very complex message, the degree of purity, legibility and reactivity is always at the highest level. But more than this list of virtues, it is the homogeneity of the Delta’s that is their greatest strength. These speakers are balanced, and therefore very pleasant to listen to, over long periods of time, and even at fairly high sound levels. Of course, they are above all fluid and luminous. But depending on the personality of your system, you may be able to «steer» the balance somewhat towards a flavour that is closer to your taste. A great vintage, for sure!

We hadn’t listened to Triangle loudspeakers since the Austral a year before, and the arrival of the Delta in our walls gave us long hours of musical pleasure. They display the traditional qualities carried by the brand: liveliness, transparency, precision. But they are also divinely balanced and homogeneous. In all sincerity, at this price, they are an excellent bargain. Of course, at 5.000 €, there are more «quoted» brands, but listen to them absolutely before you buy at this price: you might be very surprised. 


€ 5.000
370 x 1230 x 386 mm on base plate
33 kg
32 Hz – 20000 Hz at +/-3 dB
120 W
8 ohms with minimum at 3.2 ohms
92 dB/W/m