At the most recent Toronto Audiofest Show, I had a stand displaying both Dave and Mojo2 systems. The Dave setup was not powered: just a show 'n tell mockup of isolated signal and power using my kit and battery power. The Mojo2, however, was live for headphone listening as per the attached drawing and pricing. My stand was busy and the response was very good; look for press and media coverage to provide show reports. In this blog, specific to the Mojo2 setup, I will convey what I recall of attendee questions and my response.
Its a lot of components. Yes, it is. Each component plays a role and I tried to minimize the chain and lower the combined pricing. Its difficult to design an aggregated solution due to capacitive/inductive coupling of RF noise within a single enclosure.
Why are the EXTREME SE filters so large? The skin effect technology uses a bulky engineered metallurgy design to achieve high performance. Also modular Neutrik connectors allow configuring RCA, BNC or TRS in the same chassis.
I'm budget limited. What's the minimum? That's a difficult question. The EXTREME SE filters are the lions share of the cost but important and unique: the upstream filter adds benefits even to the cleanest digital source and the downstream filter prevents headphone cable antenna noise from coming back into Mojo2. PGGB 256 saves cost and storage overhead - but the sound is addictive. I would set a budget and contact me.
Can I use my expensive USB cable? Yes, use it in place of my standard ferrite-filtered USB cable offering. My signal isolation uses dual-BNC (Dual-data-rate digital) which is an AES industry standard supporting up to 768kHz audio at 24-bits. With direct USB users have reported potential difficulty with Mojo2's micro-USB port at this speed.
Can your solution be configured with an external amp? Yes, definitely. Some users may prefer a more powerful or dynamic amplifier with hard-to-drive headphones. Additionally, a pre-amp/amp with Mojo2 as a traditional line-level DAC is a killer combo. In this case, order the downstream EXTREME SE filter configured with RCA input and output.
Can the Mojo2 be permanently powered? Yes. An 'Intelligent Desktop Mode' is enabled when 5vdc fully charges the Mojo2 battery. In this case, particularly when paired with an EXTREME SE DC filter, users are reporting that Mojo2 transparency (particularly timbre) improves further, ostensibly due to disabling of the Mojo2 battery charging/monitoring circuits.
Can I stream instead of only local playback? Streaming players limit the playback to the content source sample rate. My reference system will work with only one half (single BNC) in use and, other than upsampling being performed by Mojo2, all the benefits remain. The user could consider a lossless streaming service (like TIDAL) for convenience combined with ROON and PGGB 256 for their reference local content.
What would i (Dan) add to make it sound even better? In my case, I have OPTO-DX in the chain; I use external 5vdc and a headphone pre-amp - all on battery power and EXTREME SE filtered.