Note that this is a discontinued product. You may want to visit the brand's page here to browse their newer products.
What reviewers think
Bloggers and YouTubers have tried this product—so we've summarized their strongest opinions below. Links to full reviews follow.
Product Strengths
- The PA40 impresses with remarkable resolution, spatiality, and dynamics that rival more expensive amplifiers
- It has a defined and articulate sound profile, precise and engaging dynamic behavior, and open, agile mid-high range that are reminiscent of studio-grade equipment
- The bass is dry, contoured, and impressively deep
- In terms of spatial imaging, it sets standards, excelling in separating voices in the stereo center almost perfectly
- When combined with the SA40, the PA40 raises the performance level to the point the reviewer considers it very good, regardless of price
- Soundstage depth will increase with better layering, and it will be more refined
- It improves control and dynamic contrast, with lower background noise and better separation
Product Considerations
- IOTAVX has been experiencing customer service issues, but the company has transitioned to new ownership, and they aim to answer everyone within 24 hours
Takeaway: The PA40 power amplifier offers high-end sound quality that stands out in the hifi market, making it a highlight for all music enthusiasts. It offers an upgrade path and improved sound quality when paired with the SA40.
All
PA40
reviews
Manufacturer details
Brand highlights
Taking a step back to look at reviewers' thoughts of the brand's entire lineup—not just this product—what stands out most is the following:
Select products
IOTAVX SA3
- Positioning: A compact stereo amplifier designed for wired audio setups for smaller spaces.
- Description: Offers Class AB amplification with a short signal path and integrated digital-to-analog conversion for clear performance, which makes it different from the more power-demanding models in the lineup. Compared to the AVXP and SA40 models, it meets basic connectivity needs at a lower cost, suiting users with moderate budgets and modest room sizes.
IOTAVX AVXP 3-230
- Positioning: A three‐channel surround amplifier intended for home theater environments.
- Description: Delivers 230W per channel with substantial buffering through a high-rated capacitor and ring-core transformer for dynamic performance, a technical edge over simpler stereo models. Compared to the SA3 and full system bundles, it offers dedicated front-channel support and robust power management for users needing enhanced home cinema functionality.
IOTAVX SA40 + PA40 Set
- Positioning: A stereo amplifier and power amplifier set aimed at more demanding listening rooms.
- Description: Pairs a refined preamp with a dedicated power section to provide balanced tonal control and extended connectivity options, setting it apart from basic models. Compared to the SA3 and standalone endstages, it delivers improved build refinement and technical versatility.
IOTAVX AVX17 + 2 x AVXP1 + 14 x AperionAudio XLR Audio Kabel Mono 1m
- Positioning: A high-end surround system bundle tailored for comprehensive home audio installations.
- Description: Integrates a preamplifier with dedicated power modules and high-quality cables, featuring advanced signal handling and low noise design that distinguishes it from simpler setups. Compared to the SA3, AVXP 3-230, and SA40 sets, it offers superior technical sophistication and connectivity options.
Our take on the brand
Look inside the brand
Our interview with the brand
What are two key technological innovations or strong opinions that differ you from other brands?
I wouldn't break it down to two key technologies, but rather to a general philosophy. With every product, we strive to optimize it for its intended use and omit unnecessary and redundant specifications. This makes the products cheaper, saves us licensing costs, and makes them less prone to errors. Take our AVX17 preamplifier as an example, which has no network, no streaming, no radio, and no DSP simulations. These are all features that are already present in another device or are never used. In return, you get good sound and picture and parametric EQs per channel, so that every customer can adjust the device to best suit themselves and their room. And the preamplifier costs "only" 1799€ and not several thousand euros.
What's your approach to customer support?
We try to provide support in the same way that we would expect from other companies. (When we shop as a private individual.) Always try to answer every email as quickly as possible (usually max 24 hours) on a business day. We are also always easy to reach by phone, and if not, we always try to call you back as quickly as possible.
First, contact the dealer/distributor. If the dealer can't help directly, we'll help either through the dealer or by contacting the customer directly.
From what we've heard from many customers, we're different to others in that we try to offer very quick and straightforward solutions. Even if the warranty has expired, anyone can contact us, and we've always found a customer-oriented solution.
What are your favorite tracks for showcasing the strength of your products?
- Keep the Wolves Away - Uncle Lucius
- The Curse - Agnes Obel
- Bungee Jump - Captain Hook
We also have an official IOTAVX playlist on Qobuz.
What other products pair best with yours?
Generally, our products can be paired with virtually any product thanks to their neutral/natural sound. We use speakers from AperionAudio (US) and BuchardtAudio (Denmark) at trade fairs and for demonstrations in our showroom.
Used
IOTAVX
What if you spend more?
.svg)
Our summary
Video review
Our take on the brand
Product Strengths
- Delivers a vividly detailed and balanced sound, handling complicated mixes with skill
- Able to extract a lot of information from digital audio files with apparent ease
- A volume lock prevents accidental volume adjustments when the device is in a pocket or bag
- Extensive specification including Bluetooth 5.4 with aptX Lossless compatibility and multiple inputs/outputs for versatile connectivity
Product Considerations
- Some reviewers feel the device is not very pocket-friendly due to its size and sharp edges, making it better suited as a transportable—rather than a truly portable—device
- The gain is set too high, making precise volume control difficult, especially with sensitive IEMs
- Using IEMatch adds output impedance, which can negatively affect the tonal balance and dynamics of some IEMs
- The length of the included USB-C cable is short, making it difficult to position the device on a desk
Comparisons (according to reviewers)
- Compared to the iDSD Diablo 1, the Diablo 2 offers slight sonic improvements and better build quality, but at a higher price
- Compared to the iDSD Signature, the iDSD Signature is considered by some to offer a better result for less money, with a more realistic instrument and vocal timbre, larger soundstage, and customizable features like crossfeed and bass boost
- Compared to the FiiO Q7, the iDSD Diablo 2 has a vivid sound, where the FiiO Q7 has a smooth and wide sound
Takeaway: The iDSD Diablo 2 is a powerful and versatile DAC/amp that enhances headphone listening with its detailed sound and extensive features. It is a good choice for users who want a high-quality audio experience on the go or at their desk.
Video review
Our take on the brand
Anni is our first-ever desktop integrated amplifier. Capable of driving both headphones and compact loudspeakers, Anni benefits from the company's proprietary ULTIMA circuit topology and is perfectly positioned to exploit the full potential of today's high-performance headphones, desktop monitors and high-resolution audio sources.
The new Anni desktop integrated amplifier forms part of the Qutest range and seamlessly complements the resolving abilities of the multi-award-winning Qutest standalone DAC and Huei phono stage. As a system, the Qutest components provide an unrivalled desktop audio solution, offering class-leading digital and analogue technologies for the modern music lover. The company's compact QSS (Qutest Stand System) modular equipment rack provides the perfect support, too.
Anni offers the recently announced dual-feed-forward error-correction circuit topology whether using headphones or compact loudspeakers. Anni's advanced technology allows it to drive any headphone load, error-monitored and compensated amplification at all times.
Benefitting from both 3.5 mm headphone outputs and ¼-inch (6.35 mm) outputs, so two can listen simultaneously, plus 4 mm banana-type loudspeaker outputs, Anni delivers 10 watts of quality ULTIMA amplification, controlled by a fascia-mounted volume control that also doubles as an input selector switch for Anni's two line-level inputs. A two-stage gain control for loudspeakers provides additional flexibility with a wide range of desktop monitors.
Product Strengths
- Joyful sound signature with detailed output
- Can power a wide range of headphones, due to Ultima technology
- Compact design, stacks perfectly with the Qutest and Huei
- Employs trickle-down Ultima technology to allow delivery of enormous peak current outputs
- Solid build quality using CNC-milled aluminum casework and good heat dissipation
- Connectivity options include headphone and speaker outputs
Product Considerations
- No gain switch for the headphone output
- Default gain level a bit high for sensitive IEMs
- More power limitations with speakers than headphones—best for smaller, efficient speakers or nearfield listening
- Runs hot, requiring good ventilation
- The volume control feels a little wobbly and might be difficult to use in a very precise way, and there is some channel imbalance at very low volumes
Comparisons (according to reviewers)
- Qutest/Anni pairing justifies its price premium thanks to a more composed and insightful presentation that offers notably more low-end authority, dynamic punch and tonal richness
- Cyrus ONE HD is plusher, showing that Anni has strong niche appeal
- The iFi xDSD Gryphon has digital inputs and built-in DAC, while Anni can power speakers
Takeaway: The Chord Electronics Anni is a compact and well-built amplifier that delivers a joyful and detailed sound, making it a great addition to a desktop setup for headphone and nearfield speaker listening. Its use of trickle-down Ultima technology ensures high-quality performance in a small package, and its ability to stack with other Chord devices makes it a good choice for those already invested in the ecosystem.
Video review
Our take on the brand
Our summary
Product Strengths
- High-quality build and aesthetics, with a metal casing and elegant fascia made to a high standard
- A clear, powerful, and spacious sound, with a presentation that is appealing right from the beginning
- Plenty of power on tap, specified at 70W per channel into 8 ohms and 100W per channel into 4 ohms
- Fantastic connectivity, with three pairs of line-level inputs, an MM phono stage, and outputs for a recorder and subwoofer
- Capable network DAC/streamer with digital controls
Product Considerations
- The dimpled effect flanking the extruded front panel gives the unit a further distinctive look, but the finish feels like plastic upon closer inspection
- The HEOS app isn't bespoke to the 40n, many of the product's set-up options can only be accessed through the unit using the included remote control
- Bluetooth pairing took longer than expected, and there were occasions when the app stopped being able to see or display the music server when switching inputs
- The lettering on the remote control is impossible to read in dim light, and the buttons are too similar in size, resulting in fumbling in the dark
Comparisons (according to reviewers)
- The Marantz Model 40n is a different proposition compared to the Marantz PM7000N, Marantz is keen to reposition itself as a luxury hifi brand and that intent is clear in the 40n's gorgeous build and aesthetics
- Rival systems such as the Cambridge Audio Evo 150 and Naim Uniti Atom do a better job of engrossing listeners in the music, being more insightful, musically engaging, and dynamically exciting by degrees
- Is super-sexy and distinctive styling, a higher level of fit and finish, a much better remote, and access to Sound United's HEOS streaming/multiroom audio platform wanted—or more coaxial and optical digital inputs, Dirac Live room-correction capabilities, more power, a more efficient topology, and access to Lenbrook's BluOS streaming/multiroom audio platform
- At first glance it's hard to distinguish the Model 40n from its slightly costlier Marantz Model 30 sibling
Takeaway: The Marantz Model 40n is a stylish and feature-packed streaming amplifier that offers a musical and inviting performance. With its versatile connectivity options and impressive sound quality, the Model 40n is a great choice for modern, lifestyle hifi systems.
Video review
Our take on the brand
What competes at this price?
Our Summary
Product Strengths
- Improved battery management offering faster charging rates and better efficiency than its predecessor
- Features a new USB-C data input for greater flexibility alongside other inputs
- Offers the world's first lossless DSP for tone adjustments without degrading sound quality, providing customization options
- Excellent resolution and dynamics with a large soundstage and extreme detail
Product Considerations
- The Mojo 2 can get warm when in a pocket for a period of time
- Complicated menu navigation with color-coded buttons that may require the manual
- Still uses Micro-USB for charging, which some find outdated
Takeaway: The Chord Mojo 2 is an exceptional DAC/headphone amplifier for those seeking high-resolution audio and customized sound in a portable format that is easy to move. Its sonic accuracy, detailed soundstage, and improved features provide a versatile and enjoyable listening experience, making it a worthwhile consideration for audio enthusiasts.
Video review
Our take on the brand
Our Summary
Product Strengths
- Versatile connectivity with both wireless (Bluetooth 5.1 with various codecs) and wired options (USB, S/PDIF, analog inputs) makes it suitable for various setups—from desktop to portable usage
- Eloquent, informative, and entertaining sound quality, able to produce clear, non-artificial sound across different headphones
- Features such as XBass II and XSpace provide additional sound shaping options for the user to customize the sound to their liking
- The aluminum build provides a robust and premium feel, with a design that's described as sleek and comfortable to handle
Product Considerations
- The user interface is not very intuitive
- Decent headphones are needed to reveal its quality
- The OLED screen can be difficult to read
- Battery life is around six to eight hours
Comparisons (according to reviewers)
- Compared to the hip-dac2, the Gryphon offers better sound quality, more features, and flexibility
- Compared to the iFi GO bar, the Gryphon is bigger and has a built-in battery, and the GO bar is much smaller and draws power from the source device
- Compared to the iDSD Diablo, the Diablo has more power for very demanding headphones, Gryphon has more functions
- Compared to the Zen DAC, the xDSD Gryphon has a more sophisticated and detailed sound
Takeaway: The iFi xDSD Gryphon is a portable and versatile device delivering high-quality sound with extensive features that cater to audiophiles. Its ability to improve sound quality from various sources and its robust build make it a worthwhile investment for music lovers on the go.
Video review
Our take on the brand
Our Summary
Product Strengths
- Punchy and musical performer
- BluOS is a treat to operate
- Convenient design as a source and amplifier in one, only needing speakers to complete the system
- Engagingly musical performer—dynamically fluid and punchy, with plenty of energy
- More neutral sounding now, making gains in clarity and insight across the frequency range
- Connectivity options are through 3.5mm headphone-type connectors, shared with mini-TosLink connections
Product Considerations
- Tough competition from other streaming amplifiers
- No way to send data out to an external DAC
- The Powernode was occasionally hard on transients and dynamic bursts
- There is no included remote
Comparisons (according to reviewers)
- The Marantz has a wider-scale, roomier soundstage and greater subtlety
Takeaway: The Bluesound Powernode is a superb streaming amplifier that is better than ever, offering excellent sonic talent and a well-rounded feature set. It provides a convenient and high-quality music experience for anyone looking to simplify their home audio setup.
Video review
Our take on the brand
Our Summary
Product Strengths
- Compact design makes it easy to fit in small spaces, like desktops or shelves
- Extensive streaming capabilities via the BluOS app are included, with support for popular services like Tidal, Spotify, and Amazon Music
- Produces a clean, clear, and capable sound with good detail
- Easy to set up and use, making it an accessible entry point for those new to hifi audio streaming
- A variety of connectivity options are offered, including HDMI eARC, optical/analog input, USB, and Ethernet
Product Considerations
- A headphone port is lacking
- Sound lacks outright nuance, dynamics, and punch compared to some rivals
- The BluOS app is required for full control, which might be a drawback for some
- The unit's maximum file resolution support is 24-bit/192kHz PCM, lower than some competitors
- Performance may be limited by the speakers connected to it
Comparisons (according to reviewers)
- Vs Bluesound Powernode (2021) — The Edge has halved the power output and lacks a headphone port compared to the Powernode (2021)
- Vs Technics SA-C600 — The Powernode Edge is not as musically expressive or deft with dynamics as the Technics SA-C600
- Vs Triangle AIO Twin — The Triangle AIO Twin is more entertaining, and is a complete system—speakers included
- Vs WiiM Amp — The WiiM Amp offers many features of BluOS and Chromecast
Takeaway: The Powernode Edge is a compact and versatile streaming amplifier that provides a great entry point into high-quality audio streaming for many. Its ease of use and comprehensive feature set make it a solid choice for modern music systems.
Video review
Our take on the brand
.png){kind=logo}
Our Summary
Product Strengths
- Fully balanced technology, with balanced inputs and outputs.
- Delivers powerful amplification, with up to 7.5 watts of power, capable of driving a wide range of headphones, including hard-to-drive models.
- Features a linear power supply with a large transformer and capacitor bank, providing a stable and powerful power source.
- Provides two current modes (50mA and 100mA) to tailor the sound tonality, allowing users to choose between a more forward/analytical sound and a warmer/fuller sound.
- Employs an R2R network for volume control, ensuring channel balance even at low volumes.
Product Considerations
- Runs quite hot due to its Class A amplification, requiring adequate ventilation, with chassis temperatures potentially reaching up to 50 degrees Celsius, and the unit may switch from 100mA to 50mA mode if it overheats.
- High power output might not be ideal for very sensitive IEMs, potentially limiting volume control flexibility.
- The preamplifier output is always active, meaning it doesn't mute when headphones are plugged in, requiring caution to prevent damage.
- The LCD display cannot be dimmed or switched off, and the red color of the 100mA mode may appear washed out.
- Some report volume slots are not regular or have large jumps, and/or that the remote control can be buggy.
Comparisons (according to reviewers)
- Vs. Topping A90 Discrete: The S17 has a richer sound, wider soundstage, and easier dynamics, especially in 100mA mode, placing it in a higher tier.
- Vs. Topping A90D: The S17 Pro is capable of even stronger dynamic swings, with a slightly cleaner and less cluttered soundstage.
- Vs. Violectric V222: The Aune S17 Pro is more 'tubey' and warmer sounding than the V222.
- Vs. HIFIMAN EF600: The Aune S17 has better volume control, higher dynamic range, better driving power, and better resolution.
Takeaway: The Aune S17 Pro is a powerful and versatile headphone amplifier that delivers rich, detailed sound, allowing listeners to experience music in new ways. With its balanced design and flexible current modes, it can enhance a wide range of headphones and audio setups.
Video review
Our take on the brand
How to buy
Amplifiers
Search all hifi products
Explore our database of 10,000+ new and 25,000+ used hifi products.
