My dedicated audio room build - QuadDiffusor's Big Dig

[QuadDiffuser]

Good news on the sourcing of my in-wall AC cables!
Keystone Cable will manufacture customized AC cables for my needs, sold in 100m spools, for just a few USDs per meter, having:

1) copper conductor insulation: XLPE (superior dielectric and durability, compared to PVC)
2) multi-stranded copper conductor bundle's gauge/thickness: 6mm2 (9AWG equiv.), and 10mm2 (7AWG equiv.)
3) multi-stranded copper conductor bundle's XLPE insulation color: brown (live) and blue (neutral), dyed to color code
4) twist frequency: exceeding 7 full rotations per meter (more consistently and tightly wound than possible using human hands)
5) sheathing - none (taped) for the 6mm2, and XLPE for the 10mm2; both will prevent unravelling of twisted conductors within
6) sheathing color: milky but transparent (polarity of the conductors will be visible - brown and blue)
7) sheathing thickness: very thin, for maximum flexibility and low-friction installation
8) sheathing will not be perfectly round, but instead conform to the bumpy contours of the twisted conductors within

As the costs are so nominal, I'll likely install both gauges of AC cables through the same PVC conduit (running between the MCB box and the AC duplexes) and determine which sounds "better" later, through experimentation.

The ground conductor will likely be a single multi-stranded copper conductor bundle of 10mm2 w/ XLPE insulation, loosely pulled through the PVC conduit, cut to the same length for all eight AC duplexes distributed throughout the component "end" of the listening room and anchored in a "star" configuration at the dedicated audio MCB, to ensure that there is no impedance delta between the ground wires.

 

[QuadDiffuser]

This old drawing (below) of the layout of the component end of the listening room is really messy, but the location of two of the AC duplexes will likely be shifted to the following locations:

1) all six duplexes will be on the ground
2) "Cluster 1" - one will be near the HRS EXRD "double width" component rack, where a single PS Audio Powerplant will provide power to the components
3) four will be located in the space near the powered loudspeakers and the monoblock amplifiers
4) "Cluster 2" - one in the center near the speakers will power a single PS Audio Powerplant

Excluding the two active loudspeakers and two monoblock amplifiers which will each have their own dedicated 20A duplex, the remaining components will be at the following two locations:

Cluster 1 - powered by a single PS Audio PowerPlant
1) Aurender N30 music server
2) Aurender N30 music server's power supply
3) SACD universal transport with I2S output
4) MSB Technology DAC (Cascade or Sentinel)'s Digital Director ("DD")

Should the Aurender be "upgraded" to Taiko's Olympus which has a large footprint of 19" x 19", the HRS rack will need to be changed to a larger size of 21"W x 19"D (instead of the standard size of 19"W x 17"D).

So, might as well go with the larger 21" x 19" size?

And, should there be a need to add an analog TT playback system with its preamplifiers, etc. in the future, there's horizontal expansion space for an additional rack. However, very long XLR balanced interconnects will be necessary to deliver the signals to the monoblock power amplifiers, something I'm not keen on doing.

Cluster 2 - powered by a single PS Audio Power Plant
1) MSB Technology DAC (Cascade or Sentinel)'s power supply chassis
2) MSB Technology DAC (Cascade or Sentinel)'s analog DAC chassis

The Cascade DAC's two chassis are very thin at 4.2" each, so when stacked they will not occupy much vertical space, and therefore ideal for placement between the two loudspeakers without causing undesirable diffraction. However, the Sentinel DAC's two chassis will be "double height" at 9.0" each, so should stacking them not be desirable sonically they can be split to the L and R (using longer XLR balanced interconnects to cover the extra distance).

Note that:
1) the digital source signal will be transmitted via optical cable, from the DD to the DAC
2) the DAC's output signal will be delivered to the monoblock amplifiers directly, with no preamplifier
3) the length of the XLR balanced interconnects can be kept very short, at less than 1.75m each to maximize signal transfer

 

[MarkusBarkus]

^^^big wow.sweet.^^^

 

[Chrisl]

“Wow” indeed.

 

[mtemur]

I don’t want to spoil your enthusiasm but you should use solid core cable. Multi stranded AC line for hifi is not good choice. It’s always been slow and lean. You may not accept it and probably will ask why but long story short, it will never ever be like a solid core. Sorry.

 

[QuadDiffuser]

I don’t want to spoil your enthusiasm but you should use solid core cable. Multi stranded AC line for hifi is not good choice. It’s always been slow and lean. You may not accept it and probably will ask why but long story short, it will never ever be like a solid core. Sorry.

Sure, would consider substitution of the current 7-strand copper cable conductor, to a solid core cable. What is the exact gauge which you've been able to install in your setup?

However, I've found that even the 4mm2 (12 AWG) solid-core conductors to be nearly impossible to bend easily, hampering installation. Is there a more malleable variant (with special extrusion) which you've found to be the solution?

What might be the audible tradeoff between using a thin 4mm2 solid-core conductor, versus a 7-stranded 10mm2 multi-stranded conductor? You mentioned that multi-stranded in wall AC cabling are comparatively slow and lean. What might a list of "Best to Worse" in wall AC conductor cables look like? I'm assuming that the Live and Negative legs of the individually insulated conductors will be tightly spiraled to mitigate transmission of common-mode RF/EMI noise (without any external shielding), with the Ground wire run separately between duplex and the MCB.

My rationale for using the latter is the superior current delivery ability of the thicker conductor, whose potential audible negatives would be mitigated through being redirected into a PS Audio Powerplant 15 (20), as well as through dedicated toroidal isolation transformers spec'd to be 6-10x the anticipated steady current draw of the component being isolated.