Lamm Industries LL1 Signature line preamplifier

I've long been impressed by the design, construction, and sound of the tubed electronics produced by Vladimir Lamm, but I'd never had a Lamm Industries product in my house. So I asked for a review sample of Lamm's flagship line-stage preamplifier, the LL1 Signature.

When it arrived, I realized I'd never asked about the price. When, in response to an e-mail, Lamm told me it cost $42,790/pair, I blinked. What kind of person spends that much on a preamp? (footnote 1) I thought about three friends, each of whom has a net worth in nine figures. Two aren't into audio, and while the third's most recent impulse purchase was a cattle ranch in Texas, he's still using the pair of Magnepan SMGs I bought for him 25 years ago.

It's ridiculous to wonder whether a $40,000 preamp is twice as good as a $20,000 preamp. Once you're soaring in the ionosphere of price, you go for the type of sound you want, cost be damned. After all, someone who spends $257,000 on a Ferrari 458 Spyder probably isn't settling for a Ferrari because he can't afford the extra $142,000 for a Rolls-Royce Phantom. He wants a Ferrari! An equipment reviewer should evaluate the sound of a component independent of its price, and then, only in the Conclusions, make some judgment that takes into account its price.

Design
The Lamm LL1 Signature is actually two monophonic line-stage preamplifiers, each with its own outboard power supply connected by an umbilical cable. Vladimir Lamm told me that the LL1's circuit began as the driver stage for his ML3 Signature power amplifier, which was designed around a powerful and linear triode tube. Lamm selected four high-transductance dual-triode tubes, connected in parallel, to achieve high current capability, low output impedance, and a good signal/noise ratio. Each LL1 chassis comprises a single-ended, class-A, mono preamplifier, with four 6N30P-DR dual-triode tubes in the signal path and TKD stepped potentiometers for each volume control. Each LL1 power supply has two 6X4 full-wave rectifier tubes, a choke filter, and two solid-state analog voltage regulators to supply DC voltage to the tube filaments.

Lamm has spared no expense on the LL1's parts. Inside are: Dale metal-film resistors; PRC wire-wound resistors; Bourns multi-turn potentiometers; Cornell Dubilier and United Chemi-Con electrolytic capacitors; Electrocube, Elcon, and Roederstein film capacitors; Hammond chokes; gold-plated Neutrik connectors; and low-noise, long-life, military-grade tubes.

814lamm.bac.jpg

Each preamp chassis has three line-level, single-ended inputs, one tape/home-theater processor loop, two switchable outputs (both single-ended and pseudo-balanced), a 12dB attenuator switch, protection circuitry designed to enable manual muting of the output signal, and built-in remote on/off for use with Lamm power amplifiers.

Setup and Use
As I unpacked the four LL1 chassis, I reflected on how talented electronics engineers sometimes take very different roads in designing cost-no-object products. The four-chassis LL1 arrived at my home in four wooden crates with a total shipping weight of 186 lbs. I compared this with Nagra's flagship line stage, the Jazz, which I reviewed in the April 2013 issue: the Jazz and its external power supply can be held in the palm of one hand. As I unpacked the LL1, I noticed that the four identically sized, not particularly large cases are rugged yet elegant. With their front handles and understated black appearance, they look like very expensive laboratory equipment.

There was no room in my Salamander Designs rack for four more boxes. My goal was to connect the LL1 to my system using 2m runs of my reference MIT interconnect and 10' runs of Accent Speaker Technology Blue Thunder speaker cables, but without having to move my speakers or remove any gear from my rack. I ended up placing two of the wooden crates on the floor between my speakers, and then set each preamp on its own crate at a 90° angle to my rack, one behind the other. I then placed the remaining two crates on the floor in front of the first two, and set a power supply atop each, positioned in front of each supply's respective preamp, each supply also at a 90° angle to my rack. Got lucky: My interconnects and speaker cables just barely reached everything, and of course I didn't want to move the speakers.

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All that aside, the LL1 isn't particularly finicky about setup. The owner's manual mentions no restrictions as to placement, and all four boxes ran very cool, the four-tubed preamps running cooler than the two-tubed power supplies. But adding four chassis to a reference system will likely require giving some serious thought to placement, and in some cases may require buying a new equipment rack.

Two ergonomic quirks of the LL1 may give some people pause: Each channel has its own volume control. That doesn't bother me—for many years, my reference line stage was an Audible Illusions Modulus L1, which is similarly designed. And the LL1 has no remote control. However, as each volume control is a stepped attenuator with 41 positions, those who are fanatical about precise channel balance will either have to count the clicks from zero in each channel when bringing up the volume, or get on their knees with a flashlight to check that each channel's volume-control knob is in precisely in the same spot.

One thing I found in the owner's manual did bother me, and it's easy to miss. The specifications page states: "Absolute Phase—Inverting." I urge Lamm to rethink the placement of this information in future manuals. I'd hate to think that any LL1 owners are listening to their preamps in inverted polarity because they didn't carefully read the manual.

Listening
I used the LL1 Signature without engaging the 12dB attenuator switch, and connected the preamp to my Audio Research Reference 75 power amp via the Lamm's pseudo-balanced outputs.



Footnote 1: The Lamm LL1 Signature isn't the most expensive tubed line stage on the market. The VAC Statement, for example, retails for $66,000.
COMPANY INFO
Lamm Industries Inc.
2513 E. 21st Street
Brooklyn, NY 11235
(718) 368-0181
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COMMENTS
otaku's picture

I guess I could listen just to mono LP's and save $21,395.

markotto's picture

I certainly hope it is "the best possible sound from a line-stage preamplifier".

Oldsport's picture

Hi John, just a thought on a possible noise source (and this may be opening a new audiophile can of worms). Do you have any compact fluorescent lights (CFLs) in your testing area? Those buggers emit RF; they may also dirty up the A/C as well, I don't know. Just hold a cheap AM radio next to one and have a listen. I won't have any in my listening room--they definitely degrade the sound. In fact, I try to have all CFLs turned off on the entire floor that my listening room is on, when I'm using it. Regards!

John Atkinson's picture
Oldsport wrote:
Do you have any compact fluorescent lights (CFLs) in your testing area? Those buggers emit RF; they may also dirty up the A/C as well

Yes I do! I don't have the Lamm available anymore but I will try replacing the CFL with a normal light bulb and see if I can change the measured noise level with a different preamp.

A subsequent discussion with Vladimmir Lamm revealed that he measures wideband signal/noise ratio with a 110kHz bandwidth whereas I use 500kHz. That would explain the differences in our measured results, especially as I have the CFL in my test lab.

John Atkinson
Editor, Stereophile

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