Audio T Verdict
The Lehmann Audio Linear is a dedicated analogue headphone amplifier that concentrates on high-quality amplification, flexible headphone matching and straightforward operation.
Its discrete Class A solid-state output stage operates without global feedback and is supported by an oversized internal power supply. Carefully selected components, including low-loss MKP capacitors within the audio path, reflect the Linear’s focus on clean and controlled signal handling.
Gain can be configured to suit headphones with very different sensitivity and power requirements. The available settings are 0dB, 10dB, 18dB and 20dB, selected using DIP switches on the underside of the amplifier.
Twin parallel headphone outputs allow two people to listen simultaneously, while the variable pre-output means the Linear can also control a power amplifier or pair of active speakers. This makes it more versatile than its uncluttered appearance initially suggests.
The Linear has been part of Lehmann Audio’s range since 2004 and remains a current model. Its longevity comes from concentrating on the fundamentals: a carefully engineered analogue circuit, adaptable gain and enough output power for a broad selection of dynamic headphones.
Lehmann Audio Linear Headphone Amplifier and Preamplifier
The Lehmann Audio Linear is a compact analogue headphone amplifier designed to work with dynamic headphones covering a wide range of impedances and sensitivity levels.
It provides two full-size headphone outputs, adjustable gain and a variable stereo pre-output. The Linear can therefore form the centre of a dedicated headphone system or operate as a single-source preamplifier with active speakers or a separate power amplifier.
Unlike the Linear USB II and Linear D, the standard Linear does not contain a digital-to-analogue converter. It is intended for use with an existing analogue source or the analogue output from a separate DAC, streamer, CD player or phono stage.
Headphone Amplification
- Discrete solid-state output stage
- Class A operation
- Zero global feedback
- Four selectable gain configurations
- Two parallel headphone outputs
- 5-ohm headphone output impedance
System Flexibility
- Analogue stereo RCA input
- Variable stereo pre-output
- Suitable for active speakers
- Suitable for a separate power amplifier
- Oversized internal power supply
- Compact 110mm-wide chassis
Discrete Class A Output Stage
The Linear uses a discrete solid-state output stage operating in Class A without global feedback.
Class A operation keeps the output devices working throughout the complete waveform rather than switching between different devices during each signal cycle. Lehmann uses this arrangement to support a natural, open presentation with consistent behaviour across different listening levels.
The zero-global-feedback circuit and carefully selected components are intended to preserve low-level information and transient detail without relying on a large overall feedback loop to correct the amplifier’s behaviour.
Adjustable Headphone Gain
Headphones vary considerably in impedance, sensitivity and the amount of voltage they require. Using too much gain can reduce the usable range of the volume control and make background noise more noticeable, while insufficient gain may prevent demanding headphones from reaching a suitable listening level.
The Linear provides the following maximum-gain configurations:
These settings are selected using DIP switches on the underside of the amplifier. This allows the Linear to be configured around the connected headphones rather than applying the same gain to every model.
Output Power for Different Headphone Loads
Lehmann specifies output power at two representative headphone impedances:
- 400mW into 60 ohms
- 200mW into 300 ohms
The 5-ohm headphone output impedance is intended to maintain controlled operation with a broad range of compatible dynamic headphones.
Output power alone does not determine whether two products are an ideal match. Headphone sensitivity, impedance behaviour, preferred listening level and gain configuration all need to be considered together.
Two Parallel Headphone Outputs
Two gold-plated Neutrik 6.35mm headphone sockets are positioned on the front panel.
The outputs operate in parallel, allowing two pairs of headphones to be used at the same time. This can be useful for shared listening or directly comparing two compatible headphone models from the same source.
When using two different headphones simultaneously, their impedance and sensitivity will affect their relative listening levels. Models with similar electrical requirements will usually be easier to compare directly.
Built-In Preamplifier Function
The Linear is more than a dedicated headphone amplifier. Its stereo RCA pre-output allows it to control:
- A pair of active loudspeakers
- A separate stereo power amplifier
- Another compatible line-level system
The pre-output has a specified output impedance of 50 ohms and is designed to handle longer cable runs when the Linear is used as a single-source preamplifier.
This makes it possible to build a compact system in which the same source and volume control are used for private headphone listening and loudspeaker playback.
An Analogue Headphone Amplifier
The standard Linear does not contain a DAC, USB input, Bluetooth receiver or network streamer.
Digital sources therefore need their own analogue output or a separate DAC. This separation can be useful when you already own a suitable digital source and want to choose the headphone amplifier and DAC independently.
Oversized Internal Power Supply
The Linear uses an internal regulated power supply rather than an external plug-in adaptor.
Lehmann deliberately oversizes the power supply for the amplifier’s stated output requirements. This provides the Class A output stage with a stable electrical foundation while keeping the complete unit within a compact enclosure.
Total power consumption is specified at 10W.
Selected Components
Low-loss MKP capacitors are used within the audio signal path, while the RCA connections use gold-plated contacts with Teflon insulation.
The two front headphone sockets are manufactured by Neutrik and also use gold-plated contacts.
The component choices and simple analogue signal path support the Linear’s focus on low distortion, channel separation and consistent operation with different headphones.
Compact Desktop Design
The Linear measures 110mm wide, 280mm deep and 50mm high, allowing it to fit comfortably into a desktop headphone system or alongside full-size hi-fi components.
Its net weight of 1.5kg reflects the internal power supply and substantial metal enclosure.
Lehmann lists aluminium faceplates in silver, black and chrome. Finish availability through Audio T may vary, so please check the selectable options shown on the page or contact your local store.
Linear or Linear II?
The Linear and Linear II are separate models within Lehmann Audio’s current range.
The Linear II builds upon the original design with a Low-Z copper circuit board, upgraded components and a higher specified signal-to-noise ratio. The product on this page is the standard Linear and should not be confused with the Linear II, Linear USB II or Linear D.
Related Products and Audio T Categories
Frequently Asked Questions
Is the Lehmann Audio Linear still a current product?
Yes. Lehmann Audio continues to list the original Linear as a current model alongside the newer Linear II and other Linear-series amplifiers.
Is the Linear a Class A headphone amplifier?
Yes. It uses a discrete solid-state Class A output stage operating without global feedback.
Does the Linear contain a DAC?
No. The standard Linear is an analogue headphone amplifier and preamplifier. A digital source will need its own analogue output or a separate DAC.
What gain settings are available?
The maximum gain can be configured to 0dB, 10dB, 18dB or 20dB using DIP switches on the underside of the unit.
How many headphones can be connected?
Two pairs of headphones can be connected simultaneously using the parallel front-panel 6.35mm outputs.
How much output power does the Linear provide?
Lehmann specifies 400mW into 60 ohms and 200mW into 300 ohms.
Can the Linear drive active speakers?
Yes. Its variable stereo pre-output allows it to control compatible active speakers or a separate power amplifier.
How many sources can be connected?
The Linear is designed as a single-source analogue headphone amplifier and preamplifier.
What is the difference between the Linear and Linear II?
The Linear II is a separate upgraded model using a Low-Z copper circuit board, revised components and a higher specified signal-to-noise ratio. This page is for the standard Linear.
What finishes are available?
Lehmann lists silver aluminium, black aluminium and chrome faceplates. Audio T availability may vary by finish.
Where is the Lehmann Audio Linear made?
The Linear is made in Germany.
Why Buy From Audio T?
- Headphone amplifier demonstrations where available
- Headphone impedance and sensitivity matching
- Gain-setting advice
- Headphone and source comparisons
- Separate DAC matching
- Active-speaker and power-amplifier setup advice
- Analogue cable guidance
- Part-exchange options
- Ongoing after-sales support
Contact your local Audio T store to arrange a demonstration of the Lehmann Audio Linear or discuss matching it with your headphones, source, DAC, active speakers or power amplifier.