Product information "NF-2405 AIR | RCA"

Breathtaking sound thanks to air insulation - we have already created many innovative designs on the way to perfect insulation, such as DUO-PE insulation or PETS (PE Tube Support). The Referenz NF-2405 cable is another true milestone and an absolute world first in the cable sector.

Normally, the conductors are kept at a distance from each other by more or less high-quality filling and insulation materials. With the NF-2405, however, the conductors run through a series of clips connected in series, which form the inner framework and give the NF-2405 exceptional flexibility for high-end cables.

The NF-2405 is manufactured entirely in Germany, like all speaker and audio cables in the Referenz series. The clips are assembled by hand with meticulous care in the company's own factory and then the Cross Link super-speed waveguide is threaded in. After this, the resulting air helix is also shielded by hand and given a PE network jacket before the finished cable is assembled using the RCA plugs we developed ourselves.

New RCA SL connector: Soldering is a reliable and well-established joining technique, but it has its drawbacks. Disadvantages include the presence of poorly conducting solder in the signal path and the emergence of low thermoelectric emfs. With the SL RCA Plug developed in-house, the connections from the signal conductor to the contact elements are precisely pressure-grouted together using a force of 1.5 tonnes. A further seemingly tiny improvement that brings great rewards in terms of audio performance.

Click here and discover the exciting details

Application: High-end audio cable
Cable diameter: 25 mm
Conductor design: Cross Link Super Speed waveguide
Conductor material: High-purity OFC copper
Conformity: CE, REACH, RoHS
Connector assembly: Pressure-grouted contacts (1.5 tonnes)
Connector housing: Solid metal
Contact enhancement: Rhodium-coated
Contact material: Tellurium copper
Customized assembly: On request
Design: Symmetrical
Dielectric: Air
Jacket: PE network jacket
Length: 1 m, 1.5 m, 2 m
Shielding: Dense copper braid, tin-plated (oxidation protection)
Product group: Home HiFi
Product category: Analog interconnects
Quality: Referenz
Technology: AIR Helix Point-to-Point Double mono
Connector: 2 x RCA > 2 x RCA
Connector highlight: RCA SL (solderless)
Made in Germany: Yes
Free trial listening: Yes
"There is hardly anything else we use so regularly and know so well as the cables from Ballrechten-Dottingen in Baden [...] There shouldn't be much room for improvement in terms of quality. Rather, the innovative Baden-based company demonstrates how air in the conductor can carry you to the top. Rarely have we been so blown away in the listening room as with the 2405 AIR cable set!" Stereo | 07-2024
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Factory Tour & Listening Session

"Furthermore, the optimized power supply ensured a consistent energy flow, resulting in a more organized soundstage with added depth. The Audiovector R8 Arreté speakers emit mid and high frequencies to the rear as well. However, the already impressive spaciousness was further refined. The improvement in coherence and precision was truly striking. Where often one aspect is gained at the expense of another (tablecloth effect), here the tablecloth seemed to expand in all directions." Audio Swiss | 01-2024
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Previous model NF-2404 AIR

“Such sound colors, but also details, dynamics, space – the NF cable from in-akustik can do everything and is never annoying, perhaps also because of the tiny amount of warmth in the sound and the fun factor that comes with cables that tend to be bass-heavy. Strong bass does not mean “unbalanced”, the balance is perfect. But accompanying double basses, plucked or bowed, sound simply stunningly tangible via this cable.” image hifi | 08-2021.
Go to the test report
Previous model NF-2404 AIR

We are extremely grateful for your support and can hardly believe that, alongside the LS-2404 AIR, our NF-2404 AIR loudspeaker cable also came out on top in the AUDIO readers' poll. Your enthusiasm is a great source of inspiration for us and we look forward to continuing to develop innovative products with and for you. and to providing first-class sound experiences. We would like to thank you for accompanying us on this exciting journey and sharing your musical moments with us!
  • Stereo set NF-2405 AIR | RCA SL
  • Quality certificate
  • Warranty card
  • CD "Der Anlagenberater"
  • Universal operating instructions
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Name
NF-2405 AIR | RCA
NF-4005 AIR | RCA
NF-1205 AIR | RCA
Rating
Description

Breathtaking sound thanks to air insulation - we have already created many innovative designs on the way to perfect insulation, such as DUO-PE insulation or PETS (PE Tube Support). The Referenz NF-2405 cable is another true milestone and an absolute world first in the cable sector.

Normally, the conductors are kept at a distance from each other by more or less high-quality filling and insulation materials. With the NF-2405, however, the conductors run through a series of clips connected in series, which form the inner framework and give the NF-2405 exceptional flexibility for high-end cables.

The NF-2405 is manufactured entirely in Germany, like all speaker and audio cables in the Referenz series. The clips are assembled by hand with meticulous care in the company's own factory and then the Cross Link super-speed waveguide is threaded in. After this, the resulting air helix is also shielded by hand and given a PE network jacket before the finished cable is assembled using the RCA plugs we developed ourselves.

New RCA SL connector: Soldering is a reliable and well-established joining technique, but it has its drawbacks. Disadvantages include the presence of poorly conducting solder in the signal path and the emergence of low thermoelectric emfs. With the SL RCA Plug developed in-house, the connections from the signal conductor to the contact elements are precisely pressure-grouted together using a force of 1.5 tonnes. A further seemingly tiny improvement that brings great rewards in terms of audio performance.

Click here and discover the exciting details

Good sound needs space! In developing our Air technology, we have proven that an audio cable’s insulation plays a decisive role and has a significant influence on the sound. This is due to dielectric losses and the electrostatic properties of the insulating materials, which burden the hi-fi system like heavy luggage and make it sluggish. By “omitting” this strain we then help the entire hi-fi chain to achieve top performance. We do this with special clips that guide the signal conductors through the cable in a row and freely suspended.

A cable’s geometry also influences these factors. Bigger distances mean less load. This is exactly where our NF-4005 AIR comes in: The AIR helix design and the cable’s dimensions create even more space and air between the signal conductors. The cable thus forms a wide audiophile corridor and rolls out the red carpet, so to speak, for every sound detail.

New RCA SL connectors (SolderLess): Soldering is a proven and established connection technology, but it is not without its weaknesses. These include the solder used in the signal path, which reduces the conductivity, and the generation of thermal voltages, even if it is kept to a minimum. With our recently developed SL (SolderLess) RCA connector, the connections from the signal conductor to the contact element are pressed with the highest precision and with a pressure of 1.5 tonnes. A further seemingly tiny improvement that brings great rewards in terms of audio performance.

Click here and discover the exciting details

Cable capacitance plays a decisive role, especially for audio cable connections between individual devices. As the signal sources are very weak and react sensitively to high cable capacitance, audio cables are virtually predestined for air insulation using air helix technology.

In addition to this, we have also developed a completely new and entirely solder-free RCA connector for the Referenz NF-1205 Air. It consists of several component parts that are only joined together during the course of the assembly process. As with the loudspeaker cable, the thin layer of enamel is first removed from the high-purity copper wires of the "Cross Link Super Speed" waveguide by machine. Then, the contact pin of the connector, which is made of tellurium copper, is pressure-grouted with the conductor using a force of 1.5 tonnes. The connection of the shielding is also completely new: It is now hermetically sealed with screws.

Click here and discover the exciting details

Price

€3,249.00*

€3,999.00*

€979.00*

Application
High-end audio cable
High-end audio cable
High-end audio cable
Cable diameter
25 mm
40 mm
13 mm
Conductor design
Cross Link Super Speed waveguide
Cross Link Super Speed waveguide
Cross Link Super Speed waveguide
Conductor material
High-purity OFC copper
High-purity OFC copper
High-purity OFC copper
Conformity
CE; REACH; RoHS
CE; REACH; RoHS
CE; REACH; RoHS
Connector assembly
Pressure-grouted contacts (1.5 tonnes)
Pressure-grouted contacts (1.5 tonnes)
Pressure-grouted contacts (1.5 tonnes)
Connector housing
Solid metal
Solid metal
Solid metal
Contact enhancement
Rhodium-coated
Rhodium-coated
Rhodium-coated
Contact material
Tellurium copper
Tellurium copper
Tellurium copper
Customized assembly
On request
On request
On request
Design
Symmetrical
Symmetrical
Coaxial
Dielectric
Air
Air
Air
Jacket
PE network jacket
PE network jacket
PE network jacket
Length
1 m; 1.5 m; 2 m
1 m; 1.5 m; 2 m
1 m; 1.5 m; 2 m
Shielding
Dense copper braid, tin-plated (oxidation protection)
Dense copper braid, tin-plated (oxidation protection)
Dense copper braid, tin-plated (oxidation protection)
Product group
Home HiFi
Home HiFi
Home HiFi
Product category
Analog interconnects
Analog interconnects
Analog interconnects
Quality
Referenz
Referenz
Referenz
Technology
AIR Helix Point-to-Point; Double mono
AIR Helix Point-to-Point; Double mono
AIR Helix Point-to-Point; Double mono
Connector
2 x RCA > 2 x RCA
2 x RCA > 2 x RCA
2 x RCA > 2 x RCA
Connector highlight
RCA SL (solderless)
RCA SL (solderless)
RCA SL (solderless)
Made in Germany
Yes
Yes
Yes
Free trial listening
Yes
-
Yes

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Thanks to the Air Helix design, the conductors run freely suspended through the length of the cable.

The Air Helix architecture permits signal conductors to be insulated to practically 100% by air. Special clips were developed to provide the supporting framework. Positioned at defined intervals inside the cables, these clips keep the helically-arranged conductors apart. Cable flexibility is assured by means of two struts that ensure the clips remain together but also at a precise distance from each other. This architecture is unique, bringing low capacitance and minimum dielectric losses – a true milestone in the search for open and unadulterated sound.

Our physical approach: Minimize losses for true-to-original playback.

Our Referenz AIR cables transport audio signals between source, amplifier and speaker in an authentic way and with a minimum of loss. You can enjoy music that precisely expresses the emotions of the artists at the time of recording – sensual, subtle, light-hearted or orchestral right through to full-blooded and rocking. Vocals and instruments are delivered in unadulterated form. Everything remains vibrant and full of emotive energy. Favorite tracks and pieces continue to trigger strong feelings even when you’ve heard them a hundred time over.

  • "And in terms of sound, it is nothing less than sensational. Anyone who thinks there can only be marginal differences between top conductors will be proven wrong by the NF-2404 in the first few seconds. [...] And rarely so much naturalness. Even those who are familiar with the quality of top cables are guaranteed to be amazed by the performance of the connection produced directly by in-akustik. Anyone who hears the air cable will be left breathless."

    Stereo - Matthias Böde | NF-2404 AIR (previous model)
  • "The NF-2404 AIR cinch cable adds magical cubic meters of sound quality compared to a competitor model. A clear vote for the in-akustik option [...] This cinch cable does everything right. The details it conveys are astonishing. It is more on the warm, bass-heavy side here. Combined with a high level of spatial analysis. Great at visualizing panoramas."

    Stereoplay | NF-2404 AIR (previous model)
  • "The three cables (LS-2404 AIR/NF-2404 AIR/AC-2404 AIR) improve an existing hi-fi system costing around €25,000 by some 15%, which is sheer luxury. This is only possible with in-akustik – most competitors can offer nothing approaching this gain. The workmanship could not be more superb, and the fact that everything is hand-made is additional balsam to the soul."

    Audio | NF-/AC-/LS-2404 AIR (previous model)
  • "In sound terms the cables demonstrate excellent transparency and structure. Anyone looking for that elusive special sound or even seeking to compensate for deficits in other equipment has definitely come to the wrong place. The cables deliver what they get at their own connection sockets – but in a crystal-clear, enormously ‘airy’ and breathtakingly open top quality."

    Fidelity - Cai Brockmann | NF-/LS-2404 AIR (previous model)

To the point

AIR Helix


The Air Helix architecture enables the signal conductors to run freely suspended through the length of the cable and permits signal conductors to be insulated to practically 100% by air.

The dielectric


Using air as a dielectric lowers capacitance to a minimum. In comparison with other insulators, using air as a dielectric leads to no increase in capacitance and creates no dielectric losses.

Multicore structure


By cleverly arranging the conductors in the multiply nested multicore structures, overlapping magnetic field areas are created that significantly reduce inductance.

The conductors


The Cross Link Super Speed waveguide avoids so-called skin effects and delivers a balanced sound, even with complex music passages and high volume levels.

RCA SL connector


The RCA-SL connector of our fifth generation Referenz AIR cable NF-2405 is now also pressure-grouted from signal conductor to contact elements with 1.5 tonnes.

Point-to-point Air Helix for end-to-end connections

A new feature in the 5th generation of in-akustik’s Air Helix architecture is the point-to-point connection. Specially designed transitions are available for each type of cable and connector. Across the complete length of the cable – point-to-point AIR Helix. It may sound trivial at first, but the results are impressive. Sound signals are transported with minimized losses, right through to the final centimeters. The sound is more detailed and dynamic than even before.

The conductor structure

The Cross Link Super Speed waveguide avoids skin effects caused by eddy currents in the conductor. Thanks to the braided structure, the waveguide is able to precisely transport even extreme current peaks. A lacquer coating around each wire prevents eddy currents within the conductor and protects against oxidation. All this results in a conductor that delivers a balanced sound consisting of vibrant and never overemphasized timbres, even in complex musical passages and at high volume levels.

The conductor material

The conductor material is a crucial factor for the transmission of sound signals. Any contamination worsens the conductance and increases the background noise. We only use pure, oxygen-free copper in our AIR cables. We ensure that only carefully selected batches of pure copper are processed. We take great pains to measure the quality of the copper before it is sent to the mill for drawing to the required cross-section over the course of a multi-stage process.

The shielding

EMC interference, from sources such as mobile phone and WiFi networks, is constantly increasing. This interference impairs the sensitive audio signal. Interference occurs when signals of different frequencies overlap. This can result in unwanted distortions that have nothing to do with the original signal. Dense shielding is therefore essential to protect the extremely sensitive music signals from this interference so that even the finest details are preserved.

Cable manufacturing unit

The beating heart of in-akustik is our manufactory. This is where our success story is rooted – permeated by a congenial working atmosphere, a love of music and a passion for detail. At in-akustik, we believe musical enjoyment stems from a listening experience that remains as close as possible to the original recording and the artist’s interpretation of the piece. That’s why we boast a committed workforce that combines curiosity with a keen sense of precision. With a fascination for music and things that are really special – like the development of our complex AIR cables.

Handmade

Each cable is handcrafted with the utmost care. Our extensive know-how and the qualifications of our team enable us to manufacture the complex cables in a customized manner. Apart from the finest of materials, our most important resource is the manual dexterity of our cable assemblers. In assembling our outstanding cables, they demonstrate meticulousness, composure and dedication.

Rigorous quality control

We manufacture in accordance with the highest standards. Rigorous quality control is carried out before, during and subsequent to assembly. We verify the tolerances of ever individual component. At every stage of manufacturing, we check the configuration and electrics for short-circuits. We also conduct functional and mechanical testing. No product leaves our manufacturing unit without a final quality check.

Did you know...

...that our NF-2405 AIR Pure Silver RCA SL (2 x 1.5 m) is made up of 195 individual components? The pure silver wire used is 1,109 m long, and the PE monofilament is 388 m long. Containing 296 drill holes, the Air Helix design of this cable type demands great dexterity on the part of the assemblers when they’re threading through the conductors.

RCA SL connectors (SolderLess)

Soldering is a reliable and well-established joining technique, but it has its drawbacks. Disadvantages include the presence of less conductive solder in the signal path and the emergence of low thermoelectric efms. The RCA-SL connector of our fifth generation Referenz AIR cable NF-2405 is now also pressure-grouted from signal conductor to contact elements with 1.5 tons, like all other Referenz AIR cables. A further seemingly tiny improvement that brings great rewards in audio performance.

Rhodium-coated

The best cable requires optimum connection technology. We use tellurium copper, a harder metal alloy that maintains the high conductivity value. Much superior to that of brass connectors. The rhodium coating ensures long-lasting contact and corrosion resistance. The stable conductivity is even maintained with frequent conversions. This is better than gold contacts, which wear out quicker.

Pressed contacts (1.5 tonnes)

The contact elements of the connectors are pressed directly into the conductor material using a special tool with a force of 1.5 tonnes. This creates a stable and reliable connection without the use of solder or ferrules. Transition resistances and negative effects are avoided to ensure optimum signal transmission.

Test listening at home now

Are you curious to know whether the AIR cables keep the finest details precisely and harmoniously on your system? Test our AIR cables or an audio component from our partner companies Primare and Audiovector in your home for 14 days with no strings attached!

Book a listening session

Or directly to the nearest dealer!

We work with a network of authorized dealers and distributors throughout the world. Arrange a listening appointment now.

Find a in-akustik partner

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