Ideon Audio IΩN+ DAC and preamp

REVIEW
Alan Sircom
Mar 26, 2025

The Ideon Audio Absolute ε range of products is an unparalleled collection of digital audio products. The full range (tested here) can stand toe-to-toe with the best of them. The Absolute ε DAC (itself tested here) has recently received a ‘Meta’ upgrade. This will be the subject of a review later. But, as the name suggests, ‘Absolute’ has a large price tag. For those who can’t quite reach Absolute levels, there’s Ideon Audio IΩN+. The IΩN DAC (with optional preamp, which is known as the ‘IΩN+’) shares much with the Absolute model. However, it is priced at a considerably more attainable level.

Like its bigger brother, the IΩN DAC uses an ESS chip. It uses the ES9028A PRO converter chip, with the ES9038 PRO in the Absolute ε. Both use dedicated software written in-house at Ideon Audio’s Athens design studio. This software is firmware-upgradable should the need arise. The USB audio input module features another ESS chip from the PRO family. Again, this chip is subject to a lot of custom coding in-house. Both Ideon DACs process PCM signals up to 32 bit/384 kHz, plus DSD64 to DSD512 natively.

No bristling

The IΩN does not bristle with digital inputs. It has USB Type B and coaxial S/PDIF via BNC or RCA. However, the inputs sport galvanic isolation. It outputs to XLR and RCA. The IΩN+ adds two analogue inputs (XLR and RCA), with one stereo set of XLR and RCA outputs. Idion uses a fully balanced circuit topology.

Ideon Audio can change the IΩN from a high-performance DAC to a high-performance DAC-meets-preamp. That change gives a heavy clue about the internal architecture of the product. It uses a discrete, low-noise, low-interference linear power supply, not a switch mode. Lots of high-quality capacitors flank the toroidal transformer. That transformer announces its presence when you try to lift the IΩN+ out of its flight case.

Ideon implemented a ‘true zero’ signal path on IΩN+ preamp stage. Less than half a millimetre separates the tracks of the internal DAC chip from the preamp stage. This short signal path minimises noise and harmonic distortion while maximising transparency and dynamic range.

The Ideon Audio IΩN+ also features a digitally (software) controlled analogue attenuator. Once again, this helps to reduce noise and distortion while increasing overall accuracy. Ideon eschews the more commonplace ‘bit chopping’ approach to digital attenuation. Instead, it designed the preamp stage as a separate device. However, this architecture requires the highest-grade components and a refreshing absence of compromises.

No compromise

Ideon Audio does not compromise component quality elsewhere, either. The IΩN and IΩN+ use the same high-precision femto clocks as their big brother. They also share an extremely low jitter power supply. Two of these clocks sit on the USB board (one for multiples of 44.1kHz sampling frequency and one for multiples of 48 kHz) and another on the actual converter board.

Even before the digital stream is tied to that clock, if it passes through USB, the signal is fed through the company’s proprietary three-stage noise-busting circuit, which is – once more – a technology drawn down from the Absolute ε. The data stream is fed through that HyperStream eight-channel digital architecture into Ideon’s own capacitors output stage… and it all seems remarkably familiar to anyone who has seen the Absolute ε design.

It invites a question: So much has trickled down from the top line, what remains to justify the big-hitter DAC? The chunky Absolute ε has a larger multistage power supply that dwarfs that of the Ideon Audio IΩN+, it runs a more selected range of chips and components, and that gives a still greater signal-to-noise ratio, and it’s even more tank-like in build!

Having heard both (albeit with some time between them and not the latest ‘Meta’ version of the Absolute ε), I can confidently say that you get what you pay for in the bigger DAC, but the IΩN comes exceptionally close in outright performance terms. Moreover, unless you are playing at the absolute (pun intended) pinnacle of audio performance, the IΩN is more than good enough.

Bass – now with added grip

They share an incredibly bold, powerful and organically ‘grippy’ bass. The Ideon Audio IΩN+ grabs hold of your speaker cones like a happy terrier and won’t let go of them until it’s satisfied with a spot of Rammstein or Infected Mushroom. That stupid smile breaks out across your face at that moment as you realise just how much precision the Ideon Audio is putting into that bass, and just how rewarding that sounds.

For non-bassheads, this also has a boon. It underpins the music in a way that gives instant solidity and authority to a piece of music. The final movement of Mahler’s Eighth Symphony [Solti, Decca] is delivered with such force that you start to wonder if the music should come with minimum safe distance recommendations. Hell, the DAC unleashes such powerful bass energy into your system you could get a suntan from Pablo Cazals playing a few Bach Cello suites [Archiv].

Listen to the title track to Night Train by Oscar Peterson [Verve] or, better yet, ‘Straight, No Chaser’ from Genius of Modern Music Vol 2 by Thelonious Monk [Blue Note]. In the former case, Peterson might play very laid back, but his vast hands were working that piano surprisingly hard. And Monk, well… he was just 20 years ahead of everyone and remains so today, but his power and control over the instrument just shines here.

Good foundations

Good bass alone does not make a DAC. Fortunately, that solid foundation underpins the rest of the performance. It is a joy to sit in front of. The level of detail and precision to that sound is only matched by its sheer musicality, very much in line with the IΩN’s bigger brother’s handling of music. Play something small, lithe and acoustic, or big, syrupy and electronic, and it just extracts the best from the performance, adding none of its character or influence. I went from Anna B Savage [in|FLUX, City Slang] to The Orb [UFOrb, Big Life] via everything from Albinoni to ZZ Top, and it just brings out those little details (like finger squeaks on nylon-stringed guitars) without losing sight of the intent of the musicians.

Few DACs in the field are equally comfortable with expansive soundstaging and an orderly sense of rhythm. It’s a mission statement of Ideon Audio because the IΩN nails both exceptionally well. I think this is the balance point, as other DACs in its class tip one way or another, even slightly.

More lobsters

We went with the DAC with the optional preamplifier. Mixing two things can either produce great things (like the guy who saw a steak and said, “I know what this needs… lobsters!”) or terrible things (like the guy who saw a steak and said, “I know what this needs… Nutella!”). Adding a preamp section to a DAC has typically delivered ‘variable’ results. The skills required to make a good DAC differ from those that produce a great preamp. The Ideon Audio IΩN+ is one of the exceptions, and the preamp is more than just some afterthought or a convenient way to cut down on some shelf space.

The IΩN+ preamp stage perfectly matches the DAC, with that outstanding bass presentation, authoritative dynamic range and superb detail shining through. It also has excellent soundstaging properties. It’s not the most feature-packed or input-laden preamp on the market. It has just two line XLR/RCA inputs and one XLR/RCA pair of preamp outputs alongside the DAC outputs. However, in sonic terms, it’s no slouch.

More inputs?

Shortcomings are very thin on the ground. Its rotary control knob takes some getting used to. The RCA, BNC, and USB digital inputs should be joined by AES/EBU and other connections at this price. Some might also expect a clock input on a DAC at this level. And that’s about it.

The Ideon Audio IΩN DAC (and IΩN+ with preamplifier) are a welcome addition. They are made for those after some proper high-end performance without the Absolute costs. Unless you are in the market for a pinnacle digital statement piece, the IΩN really stands out among its rivals. That bass is so intrinsically ‘right’ that it single-handedly justifies the price of admission, in my opinion. Set aside the sleek advertising and fancy front panels of some of the better-known big hitters. Instead, concentrate on what sounds fantastic. And then, the Ideon Audio IΩN DAC is the one to beat.

Technical specifications

Type: DAC with optional preamplifier stage
Digital inputs: 1x RCA S/PDIF, 1x BNC S/PDIF. 1x USB Type B
Analogue inputs (IΩN+ only) 2x RCA stereo line level input, 2x XLR line level inputs
Supported formats: 44.1kHZ-384kHz PCM, up to 32 bits. Native DSD up to 8x DSD
THD (A-weighted, 20Hz-20kHz, DAC section): <-110dB
Channel Separation (IΩN, IΩN+): >130dB
Dynamic Range: 132dB (IΩN), 121dB (IΩN+ line inputs)
Finish: Black, Silver
Dimensions (WxHxD): 46x8x30cm
Weight: 13kg
Price: IΩN £16,950, $17,900, €16,900
IΩN+ £19,950, $22,000, €19,900