Lumin A1 in 2023

[Torben_Rick (Torben - A Dane living in Hamburg - Roon Lifer)]

Not much inside

Torben

[Collin_Bruce]

Doesn’t matter that they are two shielded sets of isolation transformers (including ground). Complexity doesn’t guarantee success.

Bottom line: they work.

[Collin_Bruce]

@wklie

@Collin_Bruce

It was actually a trial-and-error thing. Connecting them in one orientation brought extreme treble and midrange clarity, but neutered the bass and dynamic impact. Reversing that orientation brought the good stuff with nothing diminished.

In that case, it’d be good if you are willing to share how the orientation should be, perhaps with photos and/or annotation of the wiring. So the other users may experiment with your choice of isolation.

Sure Peter. My pleasure to do so!

I place the ‘X’ on the decal toward the Lumin for the Lumin-adjacent isolator (D facing the switch), as pictured. The other Isolator is adjacent to my switch in my data closet; Inverse orientation - X of the decal facing the switch and D facing the Lumin.

[wklie (Peter Lie)]

I’m slightly confused by “X on the decal toward the Lumin” and “D facing the Lumin” since there is only one RJ45 network port in the Lumin.

Why are two isolators used? One for Lumin and one for the switch?

Do you mean something like this:

Uplink - D-Isolator-X - Switch - D-Isolator-X - Lumin ?

[Collin_Bruce]

Sorry for the confusion. The isolators are meant to work on long runs of Ethernet. I have a 6" length of shielded Cat8 Ethernet that connects directly to the Lumin. This plugs into the ‘near’ isolator. Then the two runs of Ethernet (roughly 60’) bring us to the data closet where my switch is. I use the other Isolator with the provided 6" pigtail into the port on my switch (which is then hardwired into my router, obv).

So:

Lumin A1 → cat8 6" → X Isolator D (based on decal) → Cat8 Ghent JSSG360 35’ → wall plate → cat 5e in-wall ~25’ run → D Isolator X (based on decal) → 6" Cat8 jumper → Switch

I emailed DX Engineering and they said that this was primarily developed for HAM radio use, to prevent long runs of Ethernet from acting as an antenna arial and collecting transmitter RFI along the length of the cable and injecting it back into the system (usually via the ground plane of shielded data cables).

[Collin_Bruce]

Lumin A1 image dump, for community posterity:

[Collin_Bruce]

Original A1 power supply:

Late production A1 (& S1) power supply… This is what I’ve got:

[Collin_Bruce]

Front panel:

[Collin_Bruce]

Just upgraded to the 15.4b firmware. Not bad for a machine more than a decade old. Bravo Lumin & Roon!

[Collin_Bruce]

Transitioned back into #ROONONLY mode yesterday. Ever after manually disabling all non-pertinent functions via the Lumin app and listening in ‘normal’ mode, moving to Roon exclusive mode is still a clearly perceived step up. Broadband punch/dynamics, purity of tone, tonal density, sense of space and air, all get observably better.