JLTi Oppo Level 4.2

133 Dalmeny Drive, Prestons NSW 2170, Australia +612-96074650 & 0412-203382

  JLTi Oppo Player        CD & DVD Player Upgrades        JLTi Tube Amps   

World-Wide Distributors
JLTi BDP Oppo Player
JLTi Oppo Level 4.2
JLTi Phono - Back Again
JLTi EL34 & KT88 Amps
What is Terra Firma?
CD/DVD Upgrades FAQ
Contact Us
Elsinore Speakers DIY
Elsinore Project Kits
JLTi EL34 Wins Shootut
About Joe Rasmussen
JLTi Interconnects
JLTi Review & Comment
Tubes & The Gainclones
DIY Tube Gainclone
Joe's FVP Page
Joe's Equipment Photos
Fletcher-Munson Curves
Joe's Photos
Real Vs False Claims?



2017 Oppo Level 4.2 - Oppo BDP-105/D

Level 4.2+ACB "Analog Clock Buffer"


From $1990.00 to $3590 Upgrades (Australia)


  1. Analog Clock Buffer (or Booster) - for a little while yet, we shall be a little coy, but it has to do with how the Clock Input of a D/A Converter works. There is a glitch that can only be overcome by a buffer, a non-switching buffer, hence an analog buffer.

  2. The Terra Firma 'Heavy' Clocking - The Terra Firma incorporates a servo control that is tuned to a few millionth of a Hertz. The end results is that it gets rid of the worse kind of jitter that occurs at ultra-low frequencies.

  3. SAW Oscillator/Clock. All Clocks are actually Oscillators and they are not digital devices at all, they are very much analogue. Conventional Oscillators are actually of the BAW type and are harmonic oscillators. BAW means Bulk-Acoustic-Wave and while they never specify themselves as BAW, it is the default if nothing is mentioned. But there is also the SAW type Oscillator. These are fundamental oscillators. Here SAW stands for Surface-Acoustic-Wave and they were not originally intended for audio use, but being non-harmonic makes them a more correct oscillator. They are not available in frequencies used in digital players and DACs - in fact, with modern manufacturing methodologies, they can make SAWs working up in the GigaHertz ranges. We first saw them in brochures slated to the military and they are also more sturdy than conventional oscillators. They praised their superior 'stability' and digital playback and Clocking is all about 'stability'. Only the Sabre DAC is compatible with SAW technology. The SAW Clocking is a winner, it just really makes the music swing, superior audible timing. We now use two SAW Clocks in the Oppos, one for the Sabre DAC and another for the Master Clock. For the latter, we had to get them custom made by Seiko Toyocom of Japan, as 54MHertz was not available. We then put that through a divide-by-two circuit to get 27MHz, the Master Clock frequency.

  4. Post-DAC Circuit - Diamond Transistor.  Want the sound that is more associated with tubes? Diamond Transistor theory. It is recognised that the humble Triode is the most linear voltage device we know and that transistors are not as linear in their native current device mode. The Diamond Transistor is not a transistor perse' - but rather is circuit method or topology, that achieves an incredible level of accuracy and works as a transconductance amplifier, where input is voltage and the output is current. Literally one point in the circuit emulates a near perfect Collector, and another point is the Base (high impedance) and finally the Emitter (low impedance). I do know one very high-end manufacturer that uses Diamond Transistors in their very best designs, and we have a lot of respect for this designer.

  5. Post-DAC Circuit - SuperReg. Basically can be described as a two-stage Regulator, a Constant Current Shunt Regulator. The first stage locks in the current and hence establishes a huge Power Supply Rejection Ratio (or PSRR) and trust me, this is a good thing. This isolates the Voltage Regulator from the worst noise. Then the Shunt fixes the Voltage. So this is effect a Class 'A' Regulator in a similar way that some Amplifiers are called Class 'A' and the speaker is the Load. Here the Load is the actual Post-DAC Circuit. The implementation is not brute force, but simply clever engineering. We first did the SuperReg way back in 1980 and now it is much more commonly used by other high-end DIY'ers and designers.

  6. New Post-DAC Filter - This is a controversial when it came out. Initially 1st Order and later 2nd Order. Most modern DAC chips are of the Delta-Sigma variety. These are essentially single-bit processing (or low bit) and have inherent noise issues that are dealt with using things like 'noise shaping' and dither to overcome the problems. Musically more authentic, more expansive midrange, better layering of depth, larger soundstage, and bass that seems to more pristinely balanced and less glare

  7. Power Supply Noise Reduction: The worst noise is the noise that impinges directly on the DAC. There is some level of recognition by the manufacturers of DAC chips and their Technical Data Sheet has recommendations, but they are woefully inadequate. There are many upgraders that will milk you for expensive components, as power supply upgrades, that have minimal benefits when other glaring problems are ignored. Hence, not just to be cost-effective, but be clever and use actual engineering solutions. In our case, we concentrate on absorbing the back-EMF noise of the DAC and while affecting a 2nd order filter effect. The former treats by far the worst kind of noise, just as we ourselves breathe in oxygen and breathe out carbon dioxide, and if you don't get rid of the carbon dioxide, it will in effect poison your environment and you. This is what back-EMF (or sometimes called 'switching noise') does. The second is to attenuate the noise that originates from the power supply. The components used, were for some times rare and expensive, but thanks to the computer industry, these devices are now highly cost-effective and even more important, they are effective!

  8. Electronic "Flywheel". Sorry if this gets a bit technical. Ted Smith, the designer of PS Audio 'Direct Stream' USB DAC makes this point too (see him on Youtube), that the two states of PDM/DSD and Delta-Sigma DACs is that the 'off' state is really, and hopefully, a clean ground. the 'on' state it really just clipping the usual +3.3V supply and that anything irregular on that supply rail goes straight into the process and is converted into jitter. We have known and this view for years, that any noise, even from ULF up, even below 1 Hertz, gets turned into jitter because jitter is noise. Ted's solution is to put a filter that filters everything above 1 Hertz. I am reading between the line, he is certainly using a passive filter and I suspect it is 3rd order. That's very good, but not good enough. We are quite aware that even 1 Hertz may not be low enough - a normal filter to have effect under 1 Hertz? we use a different solution. Store a LOT of energy near the DAC, a HUGE amount, and that energy will act as a "Flywheel" and resist changes and aberrations, even way below 1 Hertz. So it is not frequency filtering in the usual sense as Ted Smith does it, but mass filtering, resisting any change in kinetic energy; as standard filtering theory implies, works both mechanically and electro-mechanically. One area that stands out is the improvement to bass definition and listening to bass textures, but there are benefits across the board, the whole audio spectrum, a new natural perspective emerges, so easy on the ear while also incredibly revealing and detailed.

  9. High Quality Silver-Clad Copper Wiring. I hear a lot of talk about Silver versus Copper and there are strong opinions. We use a wire that is sonically in neither camps and yet use both Copper and Silver. This wire is totally down the middle, extremely clear and also homogenous sounding, very even-handed and not at all Hi-Fi'ish. I even make my own Interconnects from this wire, which is made by a UK company and I order 100 Metres at a time. Not cheap and not super expensive, it has never let me down.



  1. What is the Output Level? The Stereo RCA Outputs are approximately 2.4V RMS and hence very healthy. The Red Book Standard is 2.0V RMS and our experience shows that 2.2V RMS is the average. The Output Level on the XLRs is the same (many will double to 4V RMS, but our output is Asymmetrical Balanced and hence stays the same).

  2. Asymmetrically Balanced? This basically means that both Pin 2 and Pin 3 on the XLR Output is the same Impedance, but that the output is only on Pin 2. This gives us good Common Mode Rejection and also simplicity of circuit, as we can power both the unbalanced RCA and the balanced XLR from the same high quality post-DAC module.

  3. Does the Upgrade improve Video? According to the feedback we have been given, the answer is evidently yes, serious videophiles loves what it does the the picture quality. This is the result of the superior SAW Master Clocking, which has benefits for both Audio and Video, all digital and analogue outputs are enhanced.

  4. Does it improve the HDMI Outputs? Most definitely yes, but keep this is mind, when using HDMI, all you are doing is transmitting digital signal to an external DAC that will most certainly not be as good as the internal Sabre DAC and the full treatment of the JLTi Oppo player. There will be an improvement, but for critical use, the Sabre DAC's treatment is where the best performance will be. But no doubt that many make good use of both features.

  5. Can the Oppo be used as a Pre-Amplifier? For all digital sources, the answer is an emphatic Yes! Please set the output of the Sabre DAC to "Variable" and use the Remote Control to select from various sources, including putting all your file music on an external hard drive (the smaller 5V hard drives are recommended as they are powered via the USB port and have less "sleep" problems). The Variable Output of the Oppo works like a top class Volume Control. The built-in Volume Control of the Sabre DAC is one of the great modern wonders of audio, it really is. It is the only DAC Volume Control that I have ever recommended with zero reservations. They really knew what they were doing and all I can say is Bravo!

  6. What improvement to Multi-Channel? We make no secret that we concentrate our efforts to the Stereo performance. But the Multi-Channel Board does show very significant improvement, but not to the same degree as the Stereo performance.

  7.  What about Movies and Video? We are mainly interested in the Oppo players for audio playback, but there is no denying that these Oppos are stellar video performers. What is of course a real bonus is that watching Movies that have well recorded sound, that the whole experience is greatly enhanced. The added dimension that great sound makes to watching cannot be understated. We can now also offer Multi-Channel upgrade, contact your installer.

  8. Cont... work in progress... almost there.




Back Home Next

Send mail to joeras@vacuumstate.com with questions or comments about this web site.
Copyright 2003-17 Joe Rasmussen & JLTi
Last modified: Tuesday November 21, 2017

Just had a terrible thought. If "intelligent design" is unscientific, then who will design our audio equipment?