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Reviewer: Srajan Ebaen
Financial Interests: click here
Source: iPod Classic 160GB (AIFF/ALAC), Cypher Labs Algorhythm Solo, Cambridge Audio iD100, 27" iMac (3.4GHz quad-core IntelCore i7, 16GB 1.333MHz RAM, 2TB hard disc, 256GB SSD drive, ADM Radeon HD 6970M with 2GB of GDDR5 memory); PureMusic 1.87; Amarra 2.3; Audirvana Plus 1.3.9.3, Audiophilleo 2, APL Hifi NWO-M
Headphones: ALO Audio recabled Audez'e LCD-2, Sennheiser HD800, beyerdynamic T5p + T1; Entreq recabled HifiMan HE5LE, HE-500 and HE-6; Ortofon e-Q7; Focal Spirit One
Headphone amps: ALO Audio Rx, ALO Audio Continental, Burson Audio HA160DS, Eximus DP1, Burson Soloist [on review], HifiMan EF-6 [on review]
Cables: ALO Audio portable links, Tombo Trøn S/PDIF cable; KingRex uArt USB cable with uPower battery supply; Zu Event power cords
Review Component Retail: €1.190
07 May 2012 10:37. "I would like to ask if you're interested in a formal review. In the coming weeks I am launching a new product from our 'small' series. The new contender is named u:c:a, a USB/coax/amplifier mainly for headphones but also as front end for 'conventional' high-end systems. Our udc1 and spa1 are selling remarkable well especially taking into account that the ad budget is kept low.


"Where a combo consisting of udc1/spa1 may be too expensive and lacking some flexibility, the u:c:a kicks in. As in any other niche there are many competitors but solid-state products using discrete parts for the amplifying stages are particularly rare. Burson, SPL and Harmony Design come to my mind but the vast majority tries to please the audience with cheap opamp constructions. At least that's my opinion. You may say that the timing for this request is bad because returning from the High End 2012 show you must have buckets of leaflets and information for products awaiting a review. Or it is just right because you can fit it in." - Ivo Linnenberg


Just right. My 20 human-year old cat—blind as a bat but no radar—had gone into convulsions the night before my planned show departure. My wife was already out of town. I thus had to consign my non-refundable reservations to the aw shucks pile. Stay put. Ivo's timing was good. And I'm an unrepentant headphone slut. I have a fondness for this exact product category. Lust and opportunity make for a potent mix. Got a light?

Ivo's €1.260 udc1 is a very minimalist USB-in XLR-out converter with BB1794A chip. The async 24/192 USB transceiver is an OEM hiFace. That's also in the Wyred4Sound DAC2, APL Hifi NWO-M and on ModWright's optional DAC board for the LS-100 preamp. To keep name dropping, think Yamamoto YDA-01 next for passive I/V conversion by 0.1% precision resistor with zero NFB. The output stage is fully discrete class A zero feedback.
udc1|spa1
Ivo's €970 spa1 headphone amp is just as minimalist and fully balanced from input to its uncompromising output of 4-pin XLR socket with ultra-wide 1MHz bandwidth. Volume control is by stepped Swiss Elna rotary. Gain is smartly selectable in 5dB increments from -5dB to +20dB via a second Elna.


With the all-in-one u:c:a we avoid the twice-of-everything balanced signal path and complex volume control. Here a familiar Alps blue pot does what it already does in my $890 Burson Audio HA160DS. Instead of the spa1's 4-pin XLR output we get a normal 6.3mm headphone port. From the udc1 we inherit the USB transceiver with i-coupler and floating power supply to stay clear of dirty USB buss power. We also inherit the basic DAC section in single-ended form. Then we add a coaxial 75Ω digital input with <50ps PLL receiver and RCA outputs. In toto the u:c:a can be a miniature preamp or—volume fully open—a minimalist always 192kHz-upsampling D/A converter with claimed 3ps master-clock oscillator.

For headfiers there's 1-watt continuous power into 1Ω. All that's backed up by a 15VA toroidal linear regulated power supply. For many the u:c:a's features really are more sensible than the exclusively balanced combo. For once Herr Ivo applied some self control reining in his ultra-purist tendencies to address ordinary civilians, not extremophiles. (Reference my prior review. It criticized the lack of certain base features on both his CD player and integrated amp which sounded spectacular but were unduly spartan in utility). There's an optional chrome-plated engraved brass face plate for some bling and sheen. Linnenberg also offers a clever alternate top plate with rack ears to float the u:c:a off a shelf when real estate is at a premium.


Extremophiles will naturally wonder. Just what might their kind give up by - uh, settling for the u:c:a? As you'll have appreciated already, model names that roll off the tongue aren't exactly Linnenberg's forté (the man's a serious engineer with roots in pro). If you've attended UCLA though you'll probably forgive the u:c:a. I asked Ivo to itemize his measures to get the €2.190 two-some down to the €1.190 one-some. The end user obviously saves 'and then some' by eliminating the need for a quality balanced interconnect and second power cord. In trade dedicated power supplies for discrete functions are consolidated into one. That's a bit like scaling back from monoblocks to an equivalent stereo amp.
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