Hardware Reviews

Trilogy 909/990

Trilogy 909

Trilogy is a small but ambitious British company that goes to massive lengths to build professional and fully featured electronics. And I mean fully featured, you wouldn’t guess by looking at the 909 preamp that it’s a hybrid design nor does it give any clues as to the flexibility of the control system, although the nature of the display suggests that it’s a little different. The manual extends to 52 pages and is not overly wordy but it does take you down through the many layers of the menu system in pretty comprehensive stages. As it was delivered the 909 displayed the day and the time by default, but as I can usually remember the former and have a good enough idea of the latter I looked into the alternatives. When the preamp is on it can show the input selected, the volume level or the Trilogy logo, or it can remain blank. It can do this permanently or time out after 30, 60 or 90 seconds and the brightness level can be automatic or at one of nine levels. Each of the six inputs can be trimmed to suit the source or set to film mode for unity gain, effectively bypassing the volume control. Are you getting the picture now?
The existence of a timed display hints at the fact that it can be programmed to turn on and off at a time that suits your listening habits, which given that it takes an hour or so to warm up is the facility that I got most use from. Nic Poulson who designs and makes Trilogy equipment recommends you leave it on 24/7 but that seems excessive for two or three hours of listening, not to mention the price of energy these days.


990 natural iso


Given the sophistication of control and very high build quality it’s surprising that the 909 is not a balanced preamplifier but has six single ended inputs and two pairs of outputs. Apparently a preamp with this feature is in the pipeline albeit higher up the wage scale. As much attention to detail goes into the circuitry inside as it does to the casework and interface. The volume control is a relay switched, shunt attenuator with precision discrete resistor arrays, you won’t find many more sophisticated approaches to this job. In the latest version of the 909, this model name has been around for a while, is a zero feedback gain stage using 6H6П triodes instead of the ECC88s of original 909. These sit in a new circuit that has greater linearity and lower output impedance so that the preamp can drive long cables. This is just a snapshot of the effort that Trilogy puts into the 909, for the full story just check out their website, it’s refreshingly short on BS.
The 990 power amp is less complex but equally well made and features scrupulous attention to detail. It has been updated with the same tubes as the preamp which provide all the voltage gain, the output stage is a unity gain MOSFET/bi-polar hybrid which delivers the current. The amp avoids overall feedback and is balanced throughout, those XLR inputs are not just there for convenience. The tube stage’s power supplies are shunt regulated and it has separate transformers for HT and filament supplies, a belt and braces approach. The output stage has a choke input power supply, an approach seen in the better tube amplifiers because it provides the stiffest supply for the output devices. The 990’s styling is blinged up with blue light, this emanates from narrow slots in each cooling tower, the tubes in the billet aluminium central spine of the amp.


990 detail heatsink


I started out using the 909 preamp alone with ATC SCM150ASL active loudspeakers, substantial beasts that were designed for the studio but which sound great in the home too. The pairing produced very strong, three dimensional imaging with the aid of Nils Lofgren’s Keith Don’t Go, a track which offered up excellent micro dynamics; the subtleties of how loud and soft the strings are plucked were clearer than usual in the context of a relaxed, easy on the ear presentation. Most remarkable is the way that the substantial ATCs manage to disappear in the soundstage, something that’s hard to imagine if you’ve ever seen a pair of these fridge sized behemoths. Tonally the result was also strong, this is usually what you get with well sorted tube components so less surprising but it’s not an area where the transistorised ATCs are usually distinguished. The 909 reveals that the limitation does not lie with the speakers at all, Nils’ acoustic guitar had a magical realism that made it extremely convincing. Rarely have I heard such well rounded and complete notes.


909 natural rear iso

990 natural rear


Timing is not always a tube strength but a cleverly conceived circuit like this proves that it’s no fault of the technology and everything to do with its implementation. The timing this pairing delivers is immaculate thanks to well defined leading edges and an absence of overhang in the bass. But my notes soon get back to tone, provided in this instance by the jazz ensemble Kairos 4tet (Everything We Hold, Naim Label), this is a great recording not least because there is so much instrumental timbre, space and colour to be revealed. The same was apparent when moving over to the 990 power amp, this time in partnership with a Townshend Allegri passive pre and Bowers & Wilkins 802 Diamonds. This combination did remarkable stuff with harpsichord and viola on Jarrett and Kashkashian’s Bach interpretations (J.S. Bach, 3 Sonaten fur Viola da Gamba und Cembalo, ECM), the instruments revealing a tonal radiance that was glorious. Going back to the Kairos 4tet proved that the quality of timing remained spot-on thanks to the grip and musicality of the amplifier. The layers of reverb and echo revealed on Michael Hedges’ Aerial Boundaries were simply breathtaking, and dynamic contrast was extremely well presented, which proves that the tube complement in this power amp is doing what it does best.

The bass is likewise reflective of the topology, it doesn’t have vice like grip but there’s plenty of extension, even rumble where its called for, but this is replete with tonal depth and so has dimensions that few solid state designs can deliver. It chugs too when the band is up to it, and on Larry Carlton Live in Tokyo this is obviously the case, there is a juiciness to the low end on here that’s very attractive. Next to the Valvet A3.5 monoblocks I generally use the Trilogy power amp has more body and tonal depth, greater intelligibility and most disturbingly greater musicality – disturbing because I really can’t afford this amp! The Valvet does have a bit more welly in the bass but this comes in a less fluid, thicker form from the all transistor monoblock. It has to be said that the Trilogy has the upper hand, but then again it also has the upper price. Going from the Allegri to the 909 results in more obvious shape to the sound if less total scale in the soundstage, the active device delivering a more rounded and smoother sound with greater tonal polish.



909 natural knob long lens


As a combination the Trilogy amps are very engaging and wonderfully subtle, they have the ability to extract weight and air, producing a sound that breathes life into everything you play. Be it Trentmoller’s electronica or Kairos 4tet’s jazz, there is a musicality that makes the sound very hard to put down. I tried them with a variety of speakers including PMC fact.8s, Caterthun Classics and Spendor D7s and in each instance achieved a result that revealed the upper limit of the speakers’ abilities to bring out the emotional and lyrical in the music. Not in the “too much love” style of some pure tube electronics but in a wideband, high definition way that makes the music pleasing to both head and heart. There’s plenty of power too, the cleaner the speaker (and source for that matter), the harder you can drive them. I had a lot of fun with Yello’s Touch for instance even though it’s not a very slick recording by modern standards.
Trilogy amplifiers are built to a standard that is rare in the UK, their design, construction and sound put them firmly in the high end. The company does such a fine job that it clearly has little time left for marketing and promotion because the products clearly deserve a much higher profile. If you are looking amplification that looks superb and sounds even better your quest may be over.


 Size (WxDxH)     424x428x99mm  
 Weight     7.5 Kg
 Inputs     6 RCA phono sockets
 Main Outputs     2 RCA phono sockets
 Send (Tape) Outputs     2 RCA phono sockets
 Output impedance (Main)     1K5 Ohms
 Frequency response    10Hz-30KHz +/- 0.5dB
 Gain (Inputs to Send outputs)     0dB
 Gain (Inputs to Main outputs)     26dB +/- 1dB
 Film Gain (Inputs to Main outputs)     0dB +/- 1dB
 Phase     Phase correct (non inverting)

 Size (WxDxH)     424x428x113mm  
 Weight     24.5 Kg
 Inputs (single ended)     2 RCA phono sockets
 Inputs (balanced)     XLR 3 pin female
 Input sensitivity     1.5V RMS for Rated output
 Rated Power (8 Ohms)     100 Watts per channel
 Rated Power (4 Ohms)     200 Watts per channel
 Recommended load impedance     4-16 Ohms
 Phase     Phase correct (non inverting)

Price when tested:
909 £6,275
990 £6,895
Manufacturer Details:

Trilogy Audio Systems


Preamplifier & power amplifier


Jason Kennedy

Distributor Details:

T +44(0)1727 865488

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