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Frequently Asked Questions

Return policy?  Return within 30 days no questions asked, although I do reserve the right to withhold a 15% restocking fee.

Support?  You will get my time and attention. I don't use a help desk service, so during daytime hours (Toronto, Canada) I will respond as soon as possible.

Please don't hesitate to contact me.

Orders?  I produce small quantities of non-stocked items. Orders will normally ship in 1-3 days. I will inform you if it's longer. Free shipping (orders over $400) uses an expedited mail service with tracking (where possible).

Define transparency?  The sound the mastering engineer hears from the mixing board and recording microphones. Very few systems have this attribute and hence so few are aware that it's even possible.

Transparency sounds natural and totally engaging ...not clinical nor hyped.

Why choose DBNC vs USB?  DBNC is two SPDIF coaxial streams, self-clocking at ~50Mbits/sec per stream. USB2 is 4 wires, ~480Mbits/sec and requires handshaking and multiple clocks. USB3 & USB4 have more wires and much higher bandwidth.

RF/EM noise mitigation is easier with DBNC: simpler protocol, lower bandwidth, less clocks and fewer wires.

IMO, DBNC into a Chord DAC is unbeatable for transparency. I cannot elevate USB to equal DBNC, despite my efforts.

Do cables make a difference?  Cables are not a DSP nor a tone control so they don't directly alter the sound. Instead the issue is their impairment as antennae and conductors of RF/EM noise that impinges on a DAC to destroy transparency. The sound changes inside the DAC not inside the cable. So when expensive cables are marketed as providing 'better' power or an 'improved' sonic trait, the reality is that they are constructed to be weak antennae (wire gauge and metallurgy/geometry) plus they have some RF/EM shielding and filtering.

Use my RF-STOP filters (AC, DC, Signal EXTREME SE) in combination with standard priced cables.

Do digital cables change the bits?  Bits are bits: nothing about a digital cable that meets technical specification can change that. Bit-perfect transmission from source to DAC is guaranteed unless faulty connectors or under-spec cables cause bitstream errors, plainly noticed as 'no sound', dropouts, pops or crackles (severe and continuous noise/static is typically associated with source driver issues). The issue of sound from digital cables is manifested because they are antennae and conductors for the negative effects of RF/EM noise on a DAC. So, when expensive digital cables are marketed as providing 'cleaner' bits, the reality is that the bits never change; instead, the cables minimize the effects of RF/EM noise through their construction, shielding and filtering.

Use OPTO-DX for optical isolation or my filters: DC-BLOCK, LP-FILTER and RF-STOP EXTREME SE in combination with standard priced cables.

TOSLINK sounds great but people say it has jitter?  DACs today have double buffered data and internal reclocking. Source jitter is no longer material to digital fidelity, however some measurable tertiary jitter may be introduced from the effects of system RF/EM noise. TOSLINK is limited to 192kHz sample rate, less than the 768kHz of DBNC but it benefits from source optical isolation.

If you want an affordable endgame, use TOSLINK from a low noise source and apply my solutions on power and downstream signal.

My sound changed when I re-racked my components; how is this possible?  It's difficult to control the RF/EM noise emissions spectrum impinging on the DAC. So, while a single change may improve the sound (filter, cable, accessory or component re-racking), ad-hoc changes are a crapshoot and do not reduce wideband RF/EM noise to guarantee maximum transparency. Instead, follow all galvanic paths from the DAC (power and signal) when considering where to apply RF/EM noise solutions.

Address radiated energy using distance separation or DAC-WRAP shielding.

OPTO-DX should optically isolate my Dave from upstream changes. Why do I still perceive tweaks to my source or network server?  Digital components connected to AC mains allow RF/EM noise to conduct through the wires in your walls to your amp (for example) which is galvanically connected to your DAC. This 'back' connection is not obvious but a significant issue.

Consider my RF-STOP EXTREME SE Signal Filter placed immediately downstream of your DAC.

I don't upsample. Can I still use SRC-DX with my streamer and obtain benefit? Yes. Using SRC-DX up to 384k sample rate will only use a single coax. In this case, set the DAC input as 'digital coax', disconnect the USB cable from the DAC to cause the USB chip to shut down to reduce internally generated RF noise. 

Consider using a single DC-BLOCK and LP-FILTER to maximize the benefit of using SRC-DX in this manner.

Do isolation footers on a DAC work?  This is normally associated with distortion in the audio band, although the physical mechanism involved with surface-mounted PCB circuits is unclear. Vibration effects also affect the signal transfer function of all friction connected cables mounted on a chassis backpanel. This adds very low level noise and modulates existing RF/EM noise.

STABILANT-22 is a liquid contact enhancer that provides the stability of a soldered joint without forming a physical bond.

I've compared a Mojo2 to my Dave system and the Dave sounds better. Comments?  As per my related blog posts, differences in system configuration matter:

  • USB galvanic isolation is likely better on Dave than Mojo2. Use DBNC (SRC-DX with recommended filters) to maximize transparency.
  • Rejection of output noise (downstream power and components) back into the DAC is likely better on Dave than Mojo2. Use RF-STOP EXTREME SE Signal filter.
  • Internal upsampling (taps) is better on Dave than Mojo2. Use PGGB 256 to level the playing field. 
  • Dave's headphone amplifier is likely better than Mojo2. Use line level.

Auditory notions of what sounds better is subjective for users. My solutions reveal the objective Mojo2, pure and unfettered.

Batteries don't deliver the same dynamics and low end as an AC powered supply. True?  DACs and system components are voiced by the manufacturer using AC power. This means senior marketing staff approve their sound - typically a 'house' sound. Instead, you want neutrality (no voicing) to benefit from the much cleaner battery power. 

My reference Mojo2 system is incredibly neutral with dynamic highs and lows.

Do you have any measurements to confirm your assertions?  Not since 2019. I used industry standard Audio Precision tools to determine what was 'not' happening in the audio band; I used Signal Hound tools to publish the benefit of OPTO-DX and SRC-DX. Later, I used detectIon of RF/EM at the DAC output as a corollary for transparency (less detected noise sounded more transparent). More recently, my adoption of battery power allowed me to more easily determine changes in sound using my own ears. I now rely on user feedback and consistent application of my rules of isolation.

I don't understand how software upsampling like PGGB 256 can sound so good.  DACs convert digital to analog in real-time - that is, interpolate the instantaneous recorded snapshot (at, say 44.1kHz or 48khz sampling) into a continuous waveform. Mathematical theory describes how to do this - and the challenge is with the implementation of that theory. DACs are full of compromises in this regard - making assumptions of what we cannot hear. PGGB (www.remastero.com) on the other hand, makes no compromise in implementation or precision and assumes that we can hear everything. 

Remastero shows PGGB 256 has a ~600dB noise floor. How can our system analog signal path possibly resolve this?  It's a deep mystery...but our ear/brain is impossibly sensitive. Perhaps this is telling us something fundamental about how music induces the feeling of qualia: subconscious images, emotions and memories that add to our experience and enjoyment.

 

 

 

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