Reference Raptor loudspeakersA truly remarkable hifi loudspeaker with fabulous looks and close to full range performance
RFC is delighted to announce the release of its all new Reference Raptor high fidelity loudspeaker. The Raptor is a true high fidelity stand mount design with unique and very attractive looks to match its extraordinary sound. Using RFC’s “Constrained Panel” design for vanishingly low cabinet colouration along with exceptional quality drivers from Scanspeak, this loudspeaker offers breathtaking scale, superior imaging and a fine real wood veneer finish.
Sound quality was the driving factor in design, and the slanted front baffle isn’t just for aesthetics; it is there to ensure that the drivers are aligned in the time domain. The off-set tweeter limits edge diffraction effects which helps keep higher frequency distortions low. Carefully pair matched to within 1dB, stereo imaging is exceptional, as is the scale which is nothing short of remarkable. This is made up of two aspects: Frequency response and dynamic range. The wide band frequency range from 32Hz to 20KHz rivals that of many floor standing loudspeakers yet these give away nothing in terms of sheer visceral scale thanks to a very wide dynamic range.
As with our Rhapsody ‘speakers, you can be assured of true craftsmanship, and the finish on these is outstanding. Various wood veneers are available (Crown cut Oak is shown). Each pair is hand veneered with only the best selected veneers, with one whole 8′ x 4’ sheet of veneer used per pair of loudspeakers. Veneer joints are virtually invisible where the edges meet the corners, and the final finish is arrived at over days rather than hours. Most veneers are given between 7 and 10 coats of a special natural oil blend, left to dry and rubbed down between coat. The final coat is left to harden for 48 hours and the surface gently buffed and polished using a sparingly applied coat of natural Carnauba and beeswax. For an alternative finish, a water based high gloss water based lacquer finish is available.
The Raptors excel with almost all genres of music thanks to decent bass performance and a natural well balanced mid range. Whether you listen to close mic’d acoustics or full orchestral or rock, these will deliver. During testing, specific recordings were listened to for subjective assessment, and things such as faint studio reverb could clearly be picked up where other ‘speakers mask such details. Phase relationship between drivers plus a high quality crossover are essential in achieving such timbrel accuracy.
The Raptors use what RFC refer to as “Constrained Panel” design, whereby main panels, such as the sides, front baffle and rear are all jointed and braced internally, even for more compact designs. The design philosophy is that major sections are “broken down” into smaller sub-divisions by the addition of bracing at key locations. the locations are chosen such that no two vertical panels share the same dimensions, thus their natural resonant frequencies differ. This has the effect of breaking up one larger resonant panel amplitude into many smaller differing panels resonance amplitudes. The net effect is to significantly lower the audible resonance that even a very sturdy cabinet contributes towards the sound so that the cabinet resonance occurs at below significant audible threshold. At RFC we don’t believe that the cabinet resonance should contribute towards speaker output at any frequency as such contributions amount to colourations of the natural sound reproduction.
Cabinet construction is from slow grown high quality Latvian Birch ply (LB Ply), with 17mm sidewalls and a lamination of LB ply to over 30mm thick for the front panels. This, in addition to the internal bracing makes for an exceptionally rigid cabinet of low colouration. Glues are specially selected such that in their set state, they remain plastic, allowing some dissipation of unwanted stored cabinet energy via the joints, whilst providing exceptional joint strength.
Internal walls are lined with acoustically absorbent foam to damp down unwanted internal reflections.
Attention to detail is given to the final finish, from careful selection of veneers, to hidden magnets glued into recesses beneath the veneer for the purpose of hold on the grilles, themselves fitted with recessed magnets. This keeps the front profile nice and neat whilst avoiding the use of cheap plastic bobbins which are prone to snapping with long term use.
The Reference Raptors each use one Scanspeak 18w/853 mid-woofer and one Scanspeak Illuminator tweeter. These are exceptional quality drive units giving outstanding performance and low distortion. They have been matched for their outstanding off-axis performance as well as on-axis. The crossover point has been carefully chosen to ensure that no sudden step on off axis response occurs, offering a seamless and truly well integrated design. These drivers are found in some very expensive high-end loudspeakers.
Revelator midwoofers are famous for their Scanspeak Sliced Paper Cones, the slices are filled with damping glue. The effect is to reduce break-up nodes in the 7″ cone, and give a midrange clarity and overall smooth frequency response which has made this top audiophile range uniquely successful. the midwoofer uses as symmetrical drive SD-1 Motor, die-cast Aluminum chassis vented below the spider. Suspension is low loss linear suspension. The driving force is a large, high output ferrite magnet system.
Illuminator Tweeter is a no-compromise member of the superb Illuminator Range. Stunning design with superb vocal rendition and excellent imaging. 6 mounting holes. Black die-cast rubber painted aluminum face plate, Diffraction Damping Rubber Front, 1″ textile dome, large roll surround, 26mm vc, all for wide dispersion. Low Fs, rear chamber design that eliminates reflections and resonances.
This tweeter features the Air-Circ “SD-2″ Neodymium 6 magnet symmetric drive motor system. Excellent wide dispersion from the large roll surround. Fully comparable both in sound output and quality to the Revelator ranges.
The Raptor crossover is designed for acoustic 12dB/octave slopes on both woofer and tweeter. Whilst many companies favour cheaper first order (6dB per octave) crossovers for the advantages of better step response, RFC believes that such designs present more problems than advantages. Lower order slopes allow significant overlap of drive unit output with the requirement for very accurate phase matching otherwise comb filtering can be significant for several octaves above and below crossover point, masking finer details and also risking running tweeters into higher distortion and even overload lower down in the frequency band.
The Raptors use a Linkwitz Riley type filter design which amongst other things allows for quick transient settling behaviour (well damped), and a very flat summed response meaning that there’s no audible peak at the crossover point which is essential where the crossover lies anywhere in the mid range. We keep the crossover point as low as possible to aid wide dispersion and to avoid running the woofer into cone breakup and beaming (although this mid woofer has smooth break up characteristics, it is still better to roll off its contribution below break up).
Many hours of measurement, including off and on-axis, plus impulse and step response measurements are used to fine tune crossover design to present as natural a sounding speaker system as possible. Crossover components are of the highest quality. We use air cored inductors throughout. To maximise speaker sensitivity and damping factors, only very low resistance inductors are used for the bass section.
Capacitors are all high quality polypropylene, including a mix of Claritycap and Mundorf capacitors. Resistors are low tolerance, high power rating non-inductive wirewound ceramics. All components are hand selected and matched to within 1%. We also tailor each crossover for each specific drive unit to ensure good pair matching between loudspeakers. We apply notch filters to squash tweeter impedance at lower frequency resonance and lower output. This reduces distortion and risk of tweeter damage. The mid woofer’s rising impedance (and rising acoustic output towards resonance) are flattened using a carefully made Zobel filter. This ensures that the amplifier sees a nominally flat impedance load and that impedance points at crossover are accurately established. Finally, the tweeter levels are padded down to match the midwoofer using an l-pad calculated to raise tweeter impedance to close to that of the midwoofer.
The Raptors are designed for positioning out from the rear wall by around 300mm, or for free space placement. They should be kept away from sidewalls where possible, and where not possible, the distance between side wall and speaker, and rear wall and speaker should not be equi-distant as this can encourage standing waves responsible for raised levels of bass-boom.
Bass output is impressive, even in free space. Mounting height from the floor to the base of the speaker should be no more than 550mm for listening distances of up to 3.5m, based upon ear height being at tweeter level (this can be adjusted to suit individual seating heights of the listener). For listening distances beyond 3.5m, either the rear of the speaker should be slightly tilted forwards or the speakers set at 50mm lower for every metre further back.
Speakers should initially be toed in so that they point towards the listener, then slowly moved out until the best stereo image results. In most cases, this will be when the tweeter axis points towards the listener’s shoulders, or when you can just see the inside face of the cabinet sides. For best results, where listening distances are no greater than 3m, the spacing should ideally be so that the listener is the same distance from the speakers as the speakers are apart.
The above is just a guide based upon design principles, but obviously,some experimentation is required due to every room having different acoustic properties.
- Type: 2-way Bass Reflex
- Sensitivity: 87dB/1w/1m
- Load: 6.5Ohms Nominal, 5.5 ohms minimum
- Frequency Response: 32Hz-20kHz
- Crossover: 12dB/Octave Linkwitz-Riley type, point to point wired, incorporating impedance flattening and notch filters for low distortion
- Dimensions: 520h X 245w X 350d
- Weight: 16Kg each (approx) (19Kg packaged per speaker)
- Recommended amplification: Minimum 40w Push-Pull (valve); Minimum 60wpc (Solid State). Higher output amplifiers work very well.
The Reference Raptors are available in the following finishes:
- Crown Cut Oak
- figured Curley Maple
- Other veneer finishes provided to special order (please enquire)
The Raptors retail price is £2,800 per matched, hand crafted pair.
The following price alterations apply:
For Maple Veneer finish, please add £135
For (Santos) Rosewood Veveer finish, please add £230
To arrange for a demonstration (home demonstrations are possible) and to order, please use the Contact Us page.
Please note, that these are hand crafted loudspeakers and that a period of 5 weeks is usually required from placement of order until delivery is possible. It is usually no longer than this.
Each pair of speakers comes with a certificate confirming serial number and pair matching, plus an owner’s manual.