The ML3 Signature is a single-ended (SE) tube amplifier utilizing a very powerful direct-heated triode GM-70 (125W plate dissipation) and a separate power supply. Combining the most sophisticated technologies and electronic design with graceful looks reminiscent of the classic era of tubes, the ML3 is our top-of-the-line, no-compromise product.

ML3_AboveOpen3Design Elements

It is a 32-watt amplifier that operates in pure class A and utilizes no overall feedback. The topology is absolutely unique and incorporates one of the most advanced power supplies ever featured in an audio device. These factors, along with the designer’s unique vision and understanding of the underlying principles of audio electronics, make the ML3 an amplifier without peer. 

With the ML3 as the centerpiece of a high-end system, the recorded event is recreated in one’s listening room with astonishing verisimilitude. The listener is able to experience an ephemeral yet tangible connection to the essence of the music. These are not empty claims. Those who have listened to the ML3 first hand have unanimously acknowledged this phenomenon and have reported it to be utterly unique in their collective experience. 

SE tube amplifiers, in general, have the potential to reproduce music with greater realism than any other amplifier type or topology. The reality, however, is another thing because of the limitations inherent in most designs. These amplifiers can sound lovely in the midrange but their low and high frequency reproduction leaves much to be desired. The ML3 overcomes these obvious limitations. The resultant sound is strikingly similar to the live event. 

Along with the ML2.2, the ML3 is practically the only SE tube amplifier available on the market that is capable of reproducing an entire range of audio frequencies – not just the exquisite midrange but also the most natural and extended bass and high frequencies. The amplifier’s innovative circuitry enables it to recreate the original spectral balance and harmonic structure of the recorded material without losing even the tiniest details and nuances. Due to its extraordinary transparency, the ML3 is also unmatched its ability to recreate a three-dimensional soundstage without boundaries and limitations. As with the ML2.2, the ML3 brings out the most natural sound performance inherent in the signal and unequivocally demonstrates what a properly designed single-ended amplifier can do.


The most advanced technical solutions have been employed in the design of this amplifier. The custom-made output transformer is of peerless quality. This, along with the sophisticated power supply and unique front-end and output stages, enables the ML3 to drive most real-world speakers and yield tremendous sonic stability under most dynamic conditions. 

The ML3 features:

Innovative front-end circuitry (this design is unique to Lamm Industries, Inc.)
Separate plate and filament transformers
Six filter chokes
Six rectifying tubes
Highest quality film capacitors for the high voltage power supply that feeds the output stage
Refined soft-start and time-delay circuitries
An option to turn the amp on/off remotely
Each amplifier is carefully constructed and handcrafted of the finest materials and world-class parts, some of which include military-graded DALE metal film resistors, PRC wire-wound resistors, CADDOCK power film resistors, BOURNS multi-turn potentiometers, CORNELL DUBILIER and UNITED CHEMI-CON electrolytic capacitors, ELECTROCUBE, ELCON and ROEDERSTEIN film capacitors, HAMMOND chokes, gold-plated NEUTRIC and FISCHER connectors, heavy-duty gold-plated binding posts, and military-graded low-noise long-life vacuum tubes.

Special attention was given to designing the plate, filament, and output transformers. They have no mechanical contact with either the transformer cover or the chassis and are suspended in a special encapsulant that almost completely absorbs residual mechanical vibrations.  This plays a significant role in assuring the consummate clarity and micro-resolution of the ML3 during sound reproduction.
The ML3 has no overall feedback loop, however the amplifier features an option that allows the user to introduce a small amount of local feedback in the output stage. Furthermore, there is a choice of two amounts of such feedback: NFB1 and NFB2, which differ in their levels. Therefore, there are three options regarding feedback use in the amplifier: no feedback, NFB1 or NFB2.

A multi-turn trimming potentiometer accessible through a special opening in the amplifier’s chassis, along with a set of test points, allows the user to adjust and measure the plate current of the output tube via an external voltmeter.   

The ML3 works on all world AC line voltages (100/120/220/230/240 V).

We strongly recommend that you have a high quality digital voltmeter on hand in order to properly adjust and control the parameters of  the ML3s. We use and recommend FLUKE model 87-V. Using a cheap voltmeter is likely to give the wrong reading of the parameters resulting in improper adjustment, and, in the end, malfunction of the amp.


12AX3/ 12BE3 tubes should be replaced every 1.5-2 years. GM-70 tube should be replaced every 1.5 years to maintain the best performance of the amplifier.