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Ultimate memory play? Player programs like PureMusic and Amarra have selectable memory play. That caches music files from fast-spinning hard disk to RAM. Playback then occurs from memory rather than hard drive. The more random access memory is installed, the more temporary music can be stored. Numerous users report sonic advantages from enhanced RAM. I still run my iMac with its stock 4GB. Certain PCs can already be exclusively or partially fitted with flash drives. Even so audio playback still runs a computer with all its high-frequency radiation, power-line noise and computational background processes. Getting off that 'grid' doesn't involve battery power (laptops or a DC-converted MacMini). It involves reintroducing a physical carrier. You need a computer to burn a CD but not to play it back. With the Invicta's card reader you only need a PC to write the card, not to read it. Portable players like HifiMan's HM-801/602 already do this but for stationary home hifi Resonessence might be first.
While SDXD cards with Microsoft's exFAT coding already exist commercially at 128GB—that standard is intended to eventually support up to 2TB—the Invicta currently relies on the Fat32 coding of SD/HC equivalents. Those cards max out at 64GB. Given navigation, less could be decidely more. Invicta's display size doesn't support album art or exploded lists. Scanning a card's contents relies on sequential back/forward skips. iTunes type users who expect alphabetical up/down search modes by artist, song, album or personalized query (ranking, genre, genius) won't be impressed. How to find stuff on a maxed-out 64GB card?


At present it might be most practical to write per-use playlists to a small card, then overwrite it for the next listening session. Sequence tunes in iTunes' playlist feature, export that list. You'll play it back beginning to end like an old-timey silver disc except without its length limit. Even a four-hour maxi program will only take minutes to card-ilogue. This does require a bit more consideration to plan a session in advance. It also eliminates full library or more targeted shuffle modes with their occasionally inspired transitions. Listeners who miss the deliberation of the analogue ritual could view event-specific card writing as very reassuring since it sidesteps the built-in twitchiness of instant everything access. Who wants to devolve into the audio analog of the channel-skipping TV maniac surfer who consumes haphazard snippets only? Why not commit to a specific programme just like a proper concert?


Given Invicta's HDMI port, I asked Mark Mallinson whether it might now or in the future feed a monitor or hand-held screen for more expanded remote navigation. After all their own small display and reliance on physical front-panel commands makes navigating a memory card impossible from anything but arm's length. I also expressed frustration that permissible files were limited to WAV. That format is notoriously unreliable for meta data. On Mac platforms anyone keen on cover art and exporting it intact to portable devices nearly invariable writes to AIFF or ALAC. I have more than 1000 CDs archived already and more are added regularly. Why should our kind convert such files to WAV just to write them to card? If eventual AIFF compatibility was just a matter of downloadable code which the Resonessence team still had to write, could/would it include cover art for external displays? How about various shuffle modes? A bit of improvisational surprise occurs even at concerts.


Tech talk intermission: I just returned from a breakfast meeting with our team. All your questions/requests are doable and we're working towards them. We very much share your vision with regard to the card and external monitor. I asked our software team to provide me with their task list. The AIFF format will be relatively easy to implement. Remote control is already built into the system and we should have this well before we start to ship production units by the end of June. You will notice the IR window just below the two USB LEDs. The remote will be multi functional and not just for volume. Here is a description of what our user interface will look like via an external monitor as per our software team's recent email.


Whenever you imagine a list of options, they will be centered on the screen and vertically listed. The selected item will either grow slightly in size or be selected with a bar (imagine a box that inverts all the colors contained within it). The main screen will have a list that contains options such as settings, source select etc. The main navigational tool would be the remote. When the memory card is selected as source, several new items will appear in the main menu list including 'Songs'. Selecting and activating songs will allow you to sort by Artist, Album, Song Name, Rating etc. When you select the method you'd like to use to sort, the songs will be sorted accordingly and displayed in a list. Since these lists will likely be very long, it might be possible to have two or three columns available so that more information is available on the screen at any one time. When a song is selected and activated, the song will begin playing. Pushing the main menu button whilst in a song will allow you to switch between affecting the volume or the song position. This allows you to fast forward/rewind. There should be something like a progress bar for both volume and position in the song. This is what we imagine the user interface to be. It will be similar to the iPod interface but different in how it displays menu items. The iPod also does not have multiple sources. We may also offer something like a 'file system' view which will display songs based on folders. This would allow users to create custom playlists with different songs/artists very easily.

Regarding the output stages, the top analog board supplies the XLR/RCA outputs and uses the ES9018 in quad mode. In XLR feed this means 4 DACs in differential mode for the left channel and the same for the right. Over the RCA output one gets four DACs in single-ended mode for each channel. There are many ways the Sabre chips can be configured for quad differential mode which involves internally tweaking the quantization amount in the DACs. Being able to control this will come in an advanced menu option with a future firmware upgrade. In our opinion it does affect the sound so this will be of value to the more advanced user who may wish to tweak the system.


The bottom board supplies the headphone outputs with an ES9016 chip in 4-channel mode (left and right for headphone 1, left and right for headphone 2). Each channel operates in dual-differential mode. There is then a high-current differential to single-ended conversion for each output. The reason we did it this way was for two purposes. 1/  we wanted independent volume control since 2 headphone users may prefer different volume levels. 2/ The two headphone outputs can actually be different audio streams.  The ES9016 chip was chosen because it best fit the headphones application performance requirements. Note that the system really has the ability to produce 6 different streams simultaneously: XLR/RCA (2 channels) + HP1 (2 channels) + HP2 (2 channels). In a forthcoming ASIO driver we will be exposing all of these as separate channels. Both analog boards are preceded by a Christex CCHD-950-20 low-phase noise clock.  We chose the 50MHz part as it has the lowest phase noise at offsets that are in the audio band. The clock has its own dedicated ultra low-noise power supply

Our engineers already spent a lot of time sweating over fundamental details and wanted me to share with you some of their conclusions particularly regarding grounding. We have performed many iterations of the PC boards to fine tune this aspect of the design. Here is their summary. 'Managing ground noise is key to high-quality operation of any DAC. The first line of attack used by all manufacturers is to make multiple power supplies and decouple those with noise from those which are sensitive. Each power supply lifts its potential relative to a common ground. With that common ground great care is taken to create a uniform boundary condition of zero volts throughout the circuit. Resonessence goes one step further. We galvanically isolate the power supplies. Galvanic isolation is more than just separate supplies. It is separate grounds as well. It prevents any unwanted current flow causing a ground drop. Signals pass over specific isolation devices between galvanic domains. Noise in one domain simply cannot affect another domain when the return current remains in the domain where the noise is generated. This is better than a well-managed ground. There is no ground current to manage. Not even the zero-volt reference node is shared. Such galvanic isolation is already used in ultra high-performance integrated circuit test machines. It is not a new idea. We simply adapted it to an audio DAC.'

Back to playing cards. Fundamentally those who abhor and reject computers for actual playback might find Invicta's SD card slot particularly appealing. Naturally one still needs a PC to get music on the card/s. And one would probably not want to rip CDs for each session but go through the time and trouble to import the entire or at least core library once and for all. That fills the music refrigerator to the rafters as it were. Like each meal that requires preparation, one then simply pulls out what's needed for the menu du jour. Here a low-capacity and cheap memory card would be perfectly sufficient for any reasonable serving.


This concept also means that for PC audio a computer no longer needs to be in the listening room or connected to it in any way. For 2011 could this perfect segregation and arguably purest form of memory play be the ultimate expression of streaming audio? Minus very obvious losses of navigational functionality at least at launch time, Invicta's memory card reader appeared to be just that. At least so I concluded before the machine actually arrived. As usual I penned the above as I envisioned the defense might present their case in the very best light. The prosecution would try to chip away at it and find faults based on hands-on evidence later.

This being my first exposure to memory-card playback, I was curious whether it would have any audible advantages over streaming music from my iMac via PureMusic 1.74's hybrid memory mode with pre-allocated RAM. If not, my specific proclivities would still prefer the card route because it eliminates active computer radiation during listening (I obviously can't avoid 'passive smoke' from neighbouring WiFi networks). I imagine that to some the Invicta's biggest feature won't be the ESS angle but the card slot.

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