Kudos Audio 505

I’m currently driving a pair of “Editor’s Pick” Kudos Audio Titan 505 loudspeakers with a Moor Amps Angel 6 power amplifier and an Angel-Pre preamplifier.  It doesn’t get much better, or does it?  How about two Angel-6s in an active loudspeaker configuration?  It could be like swapping a Porsche 911 on the M5 to Bristol (Audio Show) for a Bentley Continental on the Bundesautobahn 8 (A8) to Munich (High End).  Enter the Kudos Audio Sigao Drive Crossover.

Design

The Sigao Drive Crossover is an external unpowered crossover for Kudos Audio loudspeakers with active drive capability. It can be used in combination with any amplification, and no power supply is required. Previously, the options for actively driving these loudspeakers were restricted to specialist-powered solutions from Linn, Naim, Devialet, and Exposure.

The Sigao Drive Crossover is designed to sit between the preamplifier and the power amplifiers, with each power amplifier driving either the treble or bass drivers in the Titan 505s (in this case) which are in active mode with their rear links removed. The Sigao Drive Crossover can drive the three-way Titan 808 active loudspeakers if you have them.

Almost any amplifier combination can be used with the Sigao Drive. The amplifier output loading of the crossover can be adjusted to match the technical requirements of virtually any amplifier combination through 5-PIN DIN impedance plugs supplied with the Sigao Drive.

Sigao Drive Crossover – rear

These plugs allow you to match the impedance of the Sigao Drive’s output perfectly to your chosen amplifiers, optimising performance. As Sigao Drive is unpowered, it has no buffer stage, hence the requirement to match its output impedance to the power amplifiers’ input impedance. Matching the impedance reduces distortion, improving sound quality. The net result of this is a tailor-made match for the amplifiers.

Additional gain plugs are supplied to match your chosen Kudos loudspeaker model. The settings are different for the Titan 505 and Titan 707 compared to the Titan 606, which is also different from the Titan 808; the same is true for the Cardea loudspeakers.

Quality

The Sigao Drive Crossover is immaculate in touch, feel and aesthetic. Aggressive angles tuck the unit neatly into the Solidsteel HiFi rack. The machined Kudos logo front and centre catches a side light, and Sigao Drive in Capitals is also ground into the top of the chassis.

Sigao Drive Crossover

Specifications and Price

Height (inc Feet): 81.5mm, Width 430mm, Depth 314mm

Weight (packaged): 11kg, 8.7kg unboxed.

Max. Consumption: 0W

List of Dealers here.
Full details are on the company’s site.

Price; £6500

If additional DIN plugs are required, say through a change of amplification, new plugs are required at £50 per plug, so for the 505, for example, this would be £100.

Impedance plugs for Naim amplification

Performance

Review Equipment

I’m driving a pair of Kudos Audio Titan 505 two-way loudspeakers with two Moor Amps Angel 6 power amplifiers (one on loan from Moor), taking input from a passive Moor Amps Angel-Pre preamplifier. The Sigao Drive sits between the Angel-Pre and the two Angel 6s.

Sigao Drive Crossover (silver) with two Moor Amps Angel 6s

The source for this arrangement is an Auralic Aries G1 streaming transport. It’s about as good as it gets streaming-wise (though one may prefer the newer ‘Outstanding’ Aries G2.2), with the still excellent Lightning DS App offering easy access to networked libraries. Of which, I have a Melco N100 library with the PlixiR Statement power supply upgrade. The library is networked through a Melco S100 Data Switch powered by the PlixiR. The Aries is also networked through the S100. The S100 switch is isolated from the router via the outstanding optical ADOT media converter connected via the built-in SFP optical media decoder. My Reference DAC is an iFi Pro iDSD with a linear power supply.

Melco N100 library, bottom left, with PlixiR Statement Power Supply, top middle; switch to the right of the library

I’m using Atlas Eos Power cables to the amplifiers and an Atlas Mavros RCA with Grun between the preamplifier and the Sigao. The same pair is between the DAC and Angel-Pre. I’m using a matching pair of Vertere Redline interconnects to the power amplifiers. I also have Atlas Mavros USB-A to USB-B between the Aries and the DAC.

I have two pairs of Kudos Audio KS-1 loudspeaker cables, one pair for treble and one pair for bass. In the previous active project, I learnt that physical symmetry in the system is critically important to the outcome, and this is the case here.

Sigao Drive Crossover, rear arrangement of the Titan 505 loudspeakers

Reference setup with Moor Amps Angel-Pre

True, pure musicality

I’m reaching for my Roget’s Thesaurus with this one, trying to avoid the classic HiFi cliches such as Dominique Fils Aimé, Dark Side of the Moon, and the words nuance and musicality. And yet, there is only one word for this setup: musicality. That’s it—true, pure musicality. The number of times I have sat here thinking, just another ten minutes, only to lose another hour or be late for tea is too many to count in the last few weeks. This is it, HiFi nirvana! Finally.

What is musicality? It is that emotional connection to the music that you get instinctively—an accurate engagement with the artist in the studio or on the stage. One of the best examples is just hearing new details in music and getting it immediately. Lifting your head from the iPad whilst listening is like hearing properly for the first time. Take Paul Simon’s Kodachrome (Qobuz 24-bit, 96kHz); the rhythm is all there, of course, but the tapping high hat in the top right-hand corner of the soundstage gets your full attention as you slip into air drums. The same rhythm is here with Stevie Wonder’s immaculate As (Qobuz 24-bit, 192kHz).

A more contemporary expression of these two rhythm kings includes Noah Kahan’s Stick Season (Qobuz 24-bit, 96kHz), and, all-time favourite track, This One’s for You (Qobuz 16-bit, 44.1kHz) by Ed Harcourt. Both tracks get me every time, and they have never felt better than this active setup. The same is true of the best album of them all (comment below!): Ryan Adams’ album Gold (Qobuz 24-bit, 96kHz).

Moor Amps Angel 6 power amplifier: this one is driving the driving the mid-bass driver in the 505s

The Sigao Drive offers profound depth with the 505s isobaric speaker arrangement reaching down to deliver pure control and intensity, particularly in the opening bars of Nirvana’s MTV Live Lake of Fire (Qobuz 16-bit, 44.1kHz). This depth may be attributed to the sound of the silence in the soundstage. Hearing silence in a track is such an amazing experience, and nothing expresses this better than Nils Frahm’s Butter Notes (Qobuz 24-bit, 96kHz), which boasts Wembley Stadium-style openness.

Overall, the excitement with this Sigao Drive has to do with the heightened energy from the overall soundstage. It is the apparent effortless grip of the loudspeaker drivers and the forward delivery of the music and space. Complex classical music does benefit from this arrangement. Only Peter Hurford will do when it comes to Bach’s Toccata (Qobuz 16-bit, 44.1kHz), and here, the rasping organ resonance is something to behold in this modest listening room that sounds like The Cathedral and Abbey Church of St Albans where Hurford recorded the piece.

T+A PSD 3100HV preamplifier

T+A PSD 3100 HV preamplifier with streaming DAC

I ran this system with this sixteen thousand seven hundred pounds DAC/preamplifier, which was exceptional. However, I have reverted to the Angel-Pre because I understand it better with the iFi DAC. The DAC in the T+A is clearly at a different level, as was the case with the DAC 200. The review of the T+A PSD 3100HV preamplifier will follow with passive Titans 505s!

Musical Interlude

https://open.qobuz.com/playlist/26015702

Here’s the Musical Interlude Playlist.

Thoughts

…it feels like Italian caffeinated coffee versus Starbucks non-caffeinated filter coffee

What is the outcome of this external passive Sigao crossover implementation with these 505 loudspeakers? I believe two key things are happening with this system. First, I have a very low noise floor, and second, I am realising a heightened energy. Let’s say it feels like Italian caffeinated coffee versus Starbucks non-caffeinated filter coffee.

The low-noise floor is because I have a truer, cleaner delivery, which is a function of the Sigao Drive. Of course, the drive is unpowered and, therefore, has no noisy power supplies associated with it. The Sigao Drive is capable of delivering the low-noise floor from the source, i.e. the Melco library, Auralic transport, and the Melco switch with the fibre optic data converter.

I referred to the second outcome, heightened energy, like caffeinated coffee. This energy is evident in plain listening with the Sigao Drive, feeding the two power amplifiers.  This means I have direct control of the individual drivers, treble and bass; this delivers the grip I was referring to. It also contributes to a wider soundstage created with depth and heightened imagery. Alongside this effortless power are more resolution, presence, and bass, with the isobaric arrangement performing better and with cleaner power.

Overall

It is nothing but the most outstanding performance and certainly the best I’ve ever heard.

This unreserved excellence reinforces my contention that Kudos makes the best loudspeakers. The Sigao Drive is the purest expression of musicality I have encountered in these last ten years. It is nothing but the most outstanding performance and certainly the best I’ve ever heard. If you are lucky enough to own a pair of Kudos loudspeakers, you might need to chat with your better half or better self and take a listen.