the discerning listener can’t help but get pulled right into the essence of music


The monaural line level preamplifier model LL1.1 Signature is a direct replacement of the LL1 Signature which has been the ultimate statement of perfection among the line level LAMM preamplifiers since its introduction in 2010. The LL1.1 proudly continues this tradition. Although the LL1 Signature integrated everything its designer had at his disposal to make it the best-sounding preamplifier, a true creator never rests on his laurels. There is always a yearning to do better even though it seems unrealistic at the time. The LL1.1 Signature is an end result of this yearning.

design elements


In a nutshell, the LL1.1 Signature includes the following upgrades and modifications as compared to the LL1 Signature:

  • increased immunity to unwanted radio frequency interferences propagated via both radiation and conduction over signal lines & AC power systems
  • increased amount of energy storage in the power supply
  • certain modifications in protection and time delay circuitries
  • improved signal/noise ratio
  • replacement of a number of critical components with newly available types of better quality
  • utilization of a technologically new type of pc-boards of superior quality, with gold-plated traces and thru-holes.

Considering that the LL1 Signature was practically a flawless design, it was difficult to make that next step to the near perfection.  When all technical issues for proper reproduction of the entire frequency range have been solved, the potential improvements shift to a different sphere – the one where the measuring criteria of the sound quality is its degree of approximation to the sound of live concert and the depth of its effect on the listener. The modifications catapulted the LL1.1 Signature precisely into that sphere – with this preamplifier in the all-Signature Lamm system the discerning listener can’t help but get pulled right into the essence of music.  The experience is almost shockingly involving and it is also an incredible chance to experience a different reality which may otherwise be nearly out of our reach.

While the LL1.1 Signature had been designed to complement the ML3 Signature amplifier to show what a sonic “match made in heaven” is like, the LL1.1 Signature will perform magic with any other appropriate power amplifier. The LL1.1 Signature features a topology that brings out the most natural sound performance in the audio path. In principle, it is a single-stage unit that basically represents the shortest possible signal path.

components


The preamplifier contains four very linear low impedance triodes paralleled into a single inverting gain stage.

The LL1.1 Signature employs a pure single-ended class A operation, with no overall feedback applied. Also featured are specially selected high-transconductance dual triodes 6N30P-EB/ 6Н30П-EB in the signal path and TKD stepped potentiometers for volume control — the best available on today’s market.

The preamplifier’s audibly neutral power supply features a full-wave vacuum rectifier.  This rectifier, together with a choke-containing filter, allows to practically get rid of the hum and buzz and, in the end, to ensure the verity of dynamic range without coloration.  Two solid-state analog voltage regulators supply dc voltage to the tube filaments (heaters). 

Other features include 3 inputs, one tape/HT processor loop, attenuator (-12 dB) switch, output 1/output 2 switches, protection circuitry designed to enable manual muting of the output signal, and built-in remote on/off for LAMM power amplifiers.

The main distinction of the LL1.1 Signature from any other comparable type of preamplifiers is its practically inaudible sonic signature.  When connected to an appropriate type of power amplifiers, especially LAMM power amplifiers, it assures the extraordinary transparency of perceived sound and recreation of a three-dimensional soundstage in the home, recording studio, etc., without boundaries and limitations.

Each preamplifier is handcrafted of the finest materials and top quality parts like military-grade DALE metal-film resistors, RCD wire-wound resistors, BOURNS multi-turn potentiometers, VISHAY electrolytic capacitors, ELECTROCUBE, ELCON and KEMET/RIFA film capacitors; HAMMOND chokes, gold-plated NEUTRIC connectors, and military-grade low-noise long-life vacuum tubes. 

A custom-designed massive damping panel installed in the preamplifier unit significantly reduces all types of mechanical vibrations which, in turn, leads to a more extended, coherent and natural bass reproduction. 

The LL1.1 Signature features a custom-designed super-low noise power transformer.  The LL1.1 Signature works on all world AC line voltages (100/120/220/230/240V).

audio critic reviews coming soon


Measurement


The following data represents the LL1.1 as performed by an independent party:
Mr. Bascom H. King of BHK Laboratory (bhk@rain.org).

Rated Output Voltage
From 20Hz-20KHz into 41-KOhm load: 1 Volt RMS
Voltage Gain
7.43 ± 2% or 17.43 ± 0.2dB.
Attenuation
3.98 ± 2% or 12 ± 0.17dB.
Absolute Phase
Inverting
Frequency Response
From 1-50 Volts RMS into 41-KOhm load: (-0.1dB) 20 Hz – 20 KHz. (-3dB) 5 Hz -140 KHz.
Slew Rate
Vout=36 Volts peak-to-peak of square-wave signal, F=10KHz; into 41-KOhm load: 47 Volts per microsecond.
Rise Time
Vout=36 Volts peak-to-peak of square-wave signal, F=10KHz; into 41-KOhm load: 0.61 microseconds.
Total Harmonic Distortion from 20 Hz – 20 KHz
Vout=1 Volt RMS into 41-KOhm load: no more than 0.03%
Vout=50 Volts RMS into 41-KOhm load: no more than 1%
Vout=1 Volt RMS into instrument load: no more than 0.03%
Vout=50 Volts RMS in to instrument load: no more than 1%
Vout=1 Volt RMS into IHF load: no more than 0.03%
Vout=30 Volts RMS into IHF load: no more than 1%
IM Distortion
60Hz: 7KHz 4:1 SMPTE:
Vout=1 Volt RMS into 41-KOhm load: no more than 0.09%
Vout=10 Volts RMS into 41-KOhm load: no more than 1%
Vout=1 Volt RMS into instrument load: no more than 0.09%
Vout=10 Volts RMS in to instrument load: no more than 1%
Inputs
Unbalanced gold plated single-ended RCA connectors.
Input Sensitivity
Vout = 1 Volt RMS into 41-KOhm load: 0.135 Volts RMS ± 2%.
Input Impedance
F=1KHz: Typically 16.5 KOhms.
Outputs
Unbalanced: gold plated single-ended RCA connectors.
Pseudo-balanced: 3-pin gold plated XLR connectors.
Balanced pin assignment: pin 1 = signal ground; pin 2 = signal output; pin 3 = not connected.
Corrected Output Impedance
F=1KHz: Typically 16.5 KOhms.
Noise
Signal-to-noise ratio, below 2 Volts RMS output, unweighted: typically 88 dB.
Signal-to-noise ratio, below 2 Volts RMS output, 22Hz – 22KHz: typically 96 dB.
Signal-to-noise ratio, below 2 Volts RMS output, A-weighted: typically 105 dB.
Operating Temperature
Operating Temperature: -4 to +104 degrees Fahrenheit (-20 to +40 degrees Celsius) ambient.
Power Supply
Nominal line voltage: 100-240 Volts 50/60Hz. Input voltage range: ±10%.
One power transformer, two vacuum tube rectifiers, five filter chokes, one high voltage (350 vdc) high energy power supply, two solid-state analog non-switching voltage regulators.
AC voltage intensively filtered by special RFI power line filter.
Power Supply Energy Storage
Power Supply Energy Storage: Approximately 257 joules.
Front Panel Controls: Preamplifier (two units)
LED control.
OUTPUT LEVEL control.
SELECTOR switches.
MONITOR switches.
ATTENUATOR (-12dB) switch.
MUTING switch.
OUTPUT 1 switch.
OUTPUT 2 switch.
Rear Panel Connectors & Controls: Preamplifier
Four INPUT CONNECTORS RCA for line inputs and TAPE (play).
One OUTPUT CONNECTOR RCA for TAPE (record).
Three OUTPUT CONNECTORS RCA (single-ended outputs).
Three gold-plated XLR CONNECTORS (pseudo-balanced outputs).
One XLR CONNECTOR (6 pins, gold-plated) for connecting the power supply cable.
Front Panel Controls: Preamplifier Power Supply (two units)
POWER switch.
OUTLETS switch.
REMOTE 1 turn-on/off switch for LAMM power amplifiers.
REMOTE 2 turn-on/off switch for LAMM power amplifiers.
Four LED controls.
Rear Panel Connectors & Controls: Power Supply
IEC 320 POWER INLET (3 lug).
Two AC OUTLETS, switched.
One XLR CONNECTOR (6 pins, gold-plated) for connecting the power supply cable.
Two REMOTE CONTROL plugs.
EARTHING POST (gold plated).
Features
Pure class A, single-stage zero feedback design, providing the shortest signal path possible.
Four low internal impedance (about 800 Ohms per triode!) very linear medium-mu duo triodes are connected in parallel, thus minimizing the internal noise of the preamplifier and ensuring the unprecedentedly low output impedance for this type of topology.
High-current drive capability, in combination with unique single-ended class A circuitry, assure the preamplifier’s capability to drive any cable and any real world load, while maintaining its practically inaudible sonic signature.
Specially designed damping panel installed in the LL1.1 Signature preamplifier effectively isolates all sensitive electronic components from any induced resonances.
Absolutely outstanding signal-to-noise ratio makes the LL1.1 Signature one of the quietest line-stage preamplifiers available on the market.
This design is unique to LAMM INDUSTRIES, INC.
AC voltage selector:
100/120/220/230/240 Volts, internally switchable.
Remote Control:
Special built-in circuit enables the remote turn on/off of LAMM power amplifiers.
Available remote link cable coordinates the remote functions of two or more amplifiers.
Safety:
Unique electronic protection circuit enables muting of the outputs until the preamplifier is stabilized after a turn-on, as well as functioning of the preamplifier in a “muting” mode during operation, and automatic switching to muting in case the AC line drops or is interrupted.

Plate voltage overload protection: 0.3 Amps slo-blo fuse, internally mounted.

AC voltage fuses: 2 Amps slo-blo for 100/120 Volts, 1 Amp slo-blo for 220/230/240 Volts, internally mounted.

 

General
Power Consumption: Typically 96 Watts.
 Burn-in Time at Factory: Minimum 72 hours.
Recommended Burn-in Time in End-user’s System: Minimum 80 hours.
Warm-up time: Minimum 25 minutes.
Unit dimensions: 4.5 inches high x 19 inches wide x 13.875 deep + 1.375 inches for front handles.
Crate dimensions: 23″ x 19″ x 10″ (58.42cm x 48.26cm x 25.4cm).
Unit weight preamplifier: 35.8 Lbs (16.2 Kg).
Unit weight power supply: 21.2 Lbs (9.6 Kg).
Shipping weight preamplifier: 53.8 Lbs (24.4 Kg).
Shipping weight power supply: 39.2 Lbs (17.8 Kg).
Tube Complement Preamplifier:
four (eight) 6N30P-EB / 6H30П-EB, first (single) amplification stage.
Tube Complement Power Supply:
two (four) 6X4, rectifier tubes.