Intro
Contents
A never-ending quest for the ideal audio device is what the English so eloquenty call ‘the agony and the ecstacy’. What if we had a preamplifier that could also be used as a stand alone DAC? And that also has analog inputs? Balanced and a single ended topology? And last but not least, a premium headphone amplifier with balanced outputs? Welcome to Lake People. We are testing the Violectric DHA V590. A ‘German Pocket Knife’.
Contrary to what the name suggests, Lake People is German. The company is located on Lake Constance, the ‘three-country border area’ between Germany, Austria and Switzerland. In the pro audio world, Lake People is known for its headphone amplifiers in compact cabinets and microphone preamplifiers. Niimbus represents the high end lineup with uncompromising audio and matching design. Violectric is more or less the best of both worlds; “sophisticated circuitry housed in sturdy cases”, in their own words. And that’s what the DHA V590 looks like; an impressively heavy black case with an impressive amount of knobs and LEDs. The reference to ‘pro’ is unmistakable.
Buttons
On the front we see from left to right a volume control, a balance control, a section for analog inputs (1 time XLR and 2 times RCA), a section for digital inputs (AES, coaxial, optical and USB), a selection for resampling (off, 1x, 2x, 4x and ‘best’).
Then selector switches where the output signal goes to. Here we can independently choose between headphone and line output. Bottom right three inputs for headphones; 2 times 6.35 mm stereo jack and 1 time balanced XLR.
Turning the DHA V590 around shows the digital and analog inputs listed. In the analog part, the dip switches allow you to adjust the input and output voltage. It is also possible to ‘bypass’ the volume control; the pre/post button on the back looks insignificant but can be the difference between roasted speakers/amplifier/ears/new windows. It’s one good reason to read the DHA V590 manual carefully. Because how can you know which circuit is controlled with the volume control? Pre or Post?
In terms of capabilities, the Violectric shows similarities with the Niimbus US4+ high end headphone amplifier. Same analog input/output options and construction; volume control is reed relay style with 256 steps.
Under the hood
When we take the lid off the DAH 590 we see a design of the electronics that reminds us a bit of Swiss audio. No wonder, they’re on the other side of the lake. The power supplies are from Talema. Those blue cubes… so to say. Very good quality indeed. Analog and digital parts are powered separately. And everything is neatly flattened with some decent caps. Clean power. Within the entire design is also taken into account analog and digital parts. No shared power supplies, no shared pcb’s.
DAC-talk
Lake People has a solid reputation in the world of headphone amplifiers; in addition, the brand had a DAC in some models. What are the considerations to come up with a combined headphone amplifier/preamp/DAC at this higher price level? We ask the mastermind behind Lake People, Fried Reim. His answer is so complete that we’ll take it from here.
“Until now (DHA V380 / DHA V590) we avoided to implement a premium DAC into a headphone amp. We offered some DAC cards to give people the freedom a have a compact DAC implemented into our headphone amps like V100, V200, V220, V280 and V281. The sound from these DAC cards was not bad at all. Similar to a good CD player, but not comparable to stand-alone DACs.
A good DAC design needs to be balanced from the chip output to the analog output sockets. This can´t be arranged inside a headphone amp with our “common” layout, meaning balanced and unbalanced analog inputs and balanced and unbalanced headphone outputs. To have the maximum flexibility (that is what our customers ask for), coming from balanced, going to unbalanced and vice versa, you need have an unbalanced signal structure inside the amp.
The stand-alone Violectric DACs until now mostly worked with Texas Instruments / Burr Brown DACs and SRCs. These chips (although most of the “sound” is made in the analog circuitry) are “straight forward” concerning their basic sound signature. We tried ESS chips but disliked them because they seem to be somehow “harsh” in the upper frequencies. We are friends of resampling/reclocking as this is the best – maybe the only – measure to come across jitter issues. All stand-alone DAC from Violectric and some from Lake People are using this technology. There are always some people who claim that resampling makes the sound somehow “darker” – and this is true because jitter pronounces high frequency hiss and distortion products which makes the sound “brighter”. You are closer to the “truth” when such effects are avoided by resampling !
Thinking about a new DAC architecture to transport more bits and higher sampling rates we learned about the AKM SRC chip 4137 with 32 bit architecture to achieve a theoretical -170 dB THD and dynamic range, giving us the freedom to do everything possible with a digital signal, be it PCM or DSD, 16, 20, 24 or 32 bit or any sample rate between 32 and 384 kHz (DSD up to 256). As a DAC chip we tried the AK4490 … 4499 family offering a little bit a soft sound signature – quite similar to the analog sound of our amps.
A resampling / reclocking feature works best with the best possible clock source. In case of DHA V590 this is a “Femto Clock” with a phase jitter lower than 10-15 s, customer of the DHA V380 have to accept a phase jitter of about 50 ps. The flagship DAC AK4499 is reserved for a stand-alone DAC from Niimbus, coming hopefully next year. We found AK 4490, 4493, 4495 and 4497 to sound quite similar with a bit better dynamic range and lower THD with rising numbers. When a DAC is implemented in a headphone amp this measure will limit the possible dynamic range and the minimum THD. So, we decided to use “only” AK4490 as the advantages of the “better” DACs can´t be realized.
The complete design of case, amp and DAC is made in-house by Lake People. The fpga from the USB input comes from Amanero. All other programming is made by us. We can only add to this story that we recognize it. The AKM DACs are just very good and we see them more and more in the equipment we test.”
