Oephi Immanence 2.5

REVIEW
Jason Kennedy
Mar 04, 2025

I’m not sure how Oephi maker Joakim Juhl does it. Especially when you hear loudspeakers like the Oephi Immanence 2.5. Not only does he make a wide range of cables but there are half a dozen speakers in the range and even some electronics, yet there only appears to be one guy. He must get some help when things get busy but the Munich High End show is a place where things are almost permanently busy and he is usually on his own. This year he shared with Supatrac, Lucas Audio Labs and Moonriver and the former at least spent a fair amount of time in the room.

It was one of the booths on the ground floor, so it was not an optimal space. However, with the Transcendance 2 stand mounts, the sound was very engaging and detailed. I reviewed that speaker last year and got a stunning result. It has a typically explicit Oephi balance, but when correctly set up, it delivers a thrilling sound that kept me up way too late.

Bigger is better

The Oephi Immanence 2.5 is a bigger and more powerful loudspeaker that also uses the Purifi drivers that Juhl likes so much, but here, he combines them with a ‘true ribbon’ tweeter in a cabinet that stands a metre tall on its spiked plinth. It looks like plenty of other speakers, but the details differ. These include that the 2.5 indicates that the woofers share bass duties, but the upper one also covers the midband. Purifi makes these drivers in Denmark, but Juhl gets them to omit the doping process typically applied, leaving the plain, uncoated paper. This will reduce weight and damping, but listening to his speakers, it becomes clear that Juhl prioritises speed over other considerations.

Oephi Immanence 2.5

The tweeter is a large 100mm plus example of the breed, which means it has good power handling but would typically have limited vertical dispersion. Loudspeaker design is about choosing your compromises. The perfect loudspeaker has yet to be agreed upon. The choice here is immediacy and transparency, which Juhl found in this ribbon. The plinth mentioned above is black and bolted to the base of the cabinet to allow a degree of horizontal movement. Oephi call this ‘hard decoupling’ as it reduces the rigidity of the fixing provided by spikes and reduces vibration at specific frequencies but doesn’t offer broadband isolation.

Extreme inclinations

The crossover is the most extreme element in the Oephi Immanence 2.5. It consists of massive copper foil inductors, DC biased capacitors and toroidal inductors. This network has a lot of metal, and it’s not on a conventional PCB but hard-wired. This element must significantly impact the sound of these speakers because it is so extreme. There is one pair of cable terminals but they are nice, pure copper examples from ETI. As Oephi makes a range of speaker cables, one might expect them to encourage bi-wiring, but for maximum coherence, a single pair is often beneficial.

The unlacquered, oiled oak veneer cabinets give the Immanence 2.5 an attractive silk finish that is not common in loudspeakers—just don’t leave a cup of tea on top of them.

It took a while

It took a while to get the sort of results I was hoping for out of the Oephi Immanence 2.5s. Joakim had warned me that they are more explicit than the Transcendence 2s, but I failed to appreciate that this meant getting everything around them working its very best. For instance, I don’t usually fit spikes under loudspeakers, as the sound without is generally more to my liking. With the Oephis, this was not an option. The sound, while good, didn’t gel and could even be too aggressive.

I compromised by putting spike receptors on the carpet, which did the trick. It also took a while to find an optimal position for them. The Immanence 2.5s have twin rear ports so cannot be too close to a wall. However, they have a warts-and-all presentation that doesn’t take any prisoners in the mids and high. The bass needs to balance that presentation. This meant quite a lot of experimentation with distance to the wall and angle of toe-in; it was very worthwhile, however.

The timing/balance equation

These Oephi Immanence 2.5s exemplify that perceived tonal balance is directly related to timing, when the timing is right everything falls into place, tonal balance is no longer an issue. Rega’s products have this quality: when something isn’t quite right, they can sound forward and thin, but once the system is singing, it’s the most engaging sound in the world. Oephi’s speakers are like this with knobs on, if something isn’t right they can be ferociously forward but get the system and the cabling working and it’s a whole other experience and one you don’t want to put down. One that won’t let you sit down in fact, at least if there’s any rhythm in the music.

Ribbon tweeters generally have a fairly mellow, relaxed character but this one is much faster and more revealing than usual, it does leading edges like you wouldn’t believe and in my room at least could not be toed in to face the listening seat and remain comfortable. Get the angle right however and you get horn style dynamics and power handling, there is clearly something different going on in the crossover.

Vinyl love

These Oephi Immanence 2.5s love vinyl. They are very good at revealing the qualities of the black analogue disc that are rarely found with digital alternatives. I got a phenomenal result with John Martyn’s Solid Air on the Rega Naia. It was even-handed, presented with strong three-dimensional imaging, and fast but not bright. The voice, guitars, keyboards, and double bass all sounded vivid and real, not least the steel strings of the acoustic guitar.

The Oephis are very sensitive to dynamic nuances. They track fluctuations in the level of notes precisely yet deliver them in a natural fashion that enhances the sense of realism. An album of piano jazz that had been on heavy rotation for a while (Liv Andrea Hauge Trio, Ville Blomster, Hubro) started to reveal greater dynamic range than was previously apparent, and this increased its power to transfix the listener quite markedly. Essentially, it sounded more alive and accurate, and that’s a quality that is very attractive in any system.

Magical realism

On Laura Marling’s ‘Soothing’ (Semper Femina), the bass line was less obvious than usual, which allowed the voice and percussion to be more prominent in the mix. The fretless bass, which usually dominates, was strong but seemed more proportional to the vocals. Joni Mitchell’s ‘Court and Spark’, on the other hand, delivered actual magical realism. It was genuinely mesmerising in a way that rarely happens and indicated that the Oephi Immanence 2.5 is quite a bit more sophisticated than many loudspeakers at this price. This was one of those cases where the timing was so obviously good that the musical message transcended the tonal balance of its presentation.

I made an interesting discovery whilst reviewing Naim’s NSS 333, NAC 332 and NAP 350 electronics through the Oephis, and it’s one that Naim themselves have known all along: DIN plugs make for significantly better timing than RCAs. A basic Naim DIN interconnect outperformed the best RCA alternatives I could lay my hands on when placed between this streamer and preamplifier. Joakim agrees on this point and offers DIN interconnects to Naim users, alongside his other cables; he makes RCA interconnects and conventionally shod but unconventionally built speaker and power cables, where conductors are spaced more widely than usual.

Thrill power

I tried his Reference power cable with my Moor Amps Angel 6 and got a stunning result that didn’t change the balance but enhanced detail resolution and timing quite notably. Playing modern material like Nils Petter Molvaer’s Quiet Corners produced a polished, three-dimensional sound that excelled in bass extension and power. Taj Mahal’s Recycling the Blues & Other Related Stuff (1972) shows its age in the limited bass but delivers the energy and musical genius of the man in a live situation. I was glued to the sound again, powerless to do anything but listen and ascend.

Oephi loudspeakers are not for those in search of easy background listening. They are made to bring the thrill power of music into the home so that you can be fully immersed in its glory. You don’t need expensive ancillaries, but they do need to be well chosen, especially with digital sources. The Oephi Immanence 2.5 is an uncompromising loudspeaker worth its weight in musical magic. Listen if you dare.

Technical specifications

Type: Two-and-a-half-way, three-driver, floorstanding speaker with reflex-loaded enclosure.
Driver complement: One 110mm ribbon tweeter; one 176mm Purifi mid/bass driver; one 176mm Purifi bass driver.
Crossover frequencies: not specified
Frequency response: 30Hz – 40kHz (in room)
Impedance: 6 Ohms
Sensitivity: 90db/2.83V/m (in room)
Dimensions (HxWxD): 1000 x 185 x 300mm
Weight: 22kg/each
Finishes: Oil treated oak real wood veneer standard. Walnut and custom finishes.
Price: £12,495, $13,495, €12,495 per pair