I'm new head-fi, and to this thread, but felt compelled to join and post my amazing first hand experience with the Lau and contribute to the community experience. As a background I did have time with the pre-production Lau which prompted my purchase of the production Lau (which to my ears is even better than the pre-production model that made the rounds lately). I still have another 100 hours of burn in left on my new amp, so more good things to come.
The built quality is outstanding, and solid. The connectors are very strong and well positioned. Its also the first audio component I've had where the power connector is firm and strong enough to hold my large Shunyata power cord without bending whatsoever. The headphone connectors are solid, with no wiggle or give, and the volume knob is responsive and has a good feel to the hand. The LEDs on the front panel are a perfect brightness (as the preproduction model was a bit too bright for me). In summary I find the build quality to be excellent with everything feeling very solid and well built.
I find the options with this amp to be excellent, allowing for SE and balanced in all conceivable configurations. The addition of low and high output switch is very helpful to me.
I'm currently using a Berkeley Alpha USB/DAC combination through balanced shunyata anaconda ICs to the Lau. My headphone is a Stefan AudioArt modified HD800 with Stefan Audioart SE endorphin cable (waiting for a balanced version which may be better still).
The sound out of the Lau is simply stunning to my ears from top to bottom it is magical and musical. Effortless is a good term. The sound is detailed and involving, creating very lifelike audio with proper instrument and voice timbre. The amp reveals the source recording exceedingly well, with the 1960's analog master tape hiss in the background on older recordings, the 1980's CDs with their slightly harsh digital upper end (which thankfully is a thing of the past), the current day digital recordings very clean but clearly processed sound. With reference recordings such as Mapleshade CDs or Reference Recordings HD tracks the sound is very true to life and musical conveying the energy and emotion of the recordings music. Having musicians in the room feeling is present on these type of recordings.
The soundstage is wide and open. Instruments are widely separated, and all the musical passages can be clearly heard. Absolutely no mash up so to speak. Imaging is razor sharp.
On the top end there is no harshness whatsoever, just clarity and liquid smooth detail and sparkle. The energy of the music is remarkable.
Mid frequencies are also smooth with accurate timbre. All frequencies from top to bottom are equal with no transition or drop off. Piano pieces especially can test this, with all notes beautifully represented.
Low frequencies are honestly beautiful, well defined, immensely powerful when present in the music (even through my HD800s - at times enough to set the HD800's vibrating). The lows ground the music and make listening seductive and full of energy and very musical.
I will be enjoying the joy of music through my Lau for many years to come, as it should grow and scale up well with any changes I make to my system. It has the remarkable ability to clearly produce and make audible even small small changes in the signal chain. When properly optimized, the Lau is truly a remarkable achievement and both emotional and an absolute pure joy to listen to. Thank you Alex Cavalli!
Computer>SOtM tX-USBexp USB card>Berkeley alpha USB/DAC>liquid gold amp>modified HD800 headphones
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