In a moment of Zen, I take a journey through my own virtual Torii gate where the Shinto Gods may bless my audio purity. This is my version of sacred divinity.



























There are a total of four stages which form a very effective barrier against mechanical vibration and resonance which is detrimental to vacuum tube stability.

This base acts as a floating shock absorber which starts with interleaved rubber/cork pedestals underneath. The interior is isolated by the formation of fifteen tennis balls which are constructed of pressurized rubber wall material.  The deck simply floats upon the balls free from touching the surrounding structure at any point. The amp base has two-inch neoprene feet as the next barrier. The amp enclosure itself acts as the final barrier to block any interaction with vibration.  You can feel the spring action with only slight pressure upon the amp. The movement returns to stable almost immediately with a very firm feel.























The Japanese writing translated into English is as follows:



                     
            GREAT DIVINITY ILLUMINATING HEAVEN


































































































































This concludes my presentation.

Wow, fantastic work. I hope it sounds as good as it looks.

JD

I can see why you named it the 'Zenith'. I'd say it's next level but it's actually exponentially next level. Quite the attention to detail on all fronts and a beautiful new case to boot. The experience you're getting in your room must be outrageous. I can't imagine once the DAC and your other music projects are complete that it can get any better, but knowing you, it will.

Thanks for taking us along on your journey and keeping the DIY dream alive.

Just to inform all that if you ever question whether or not it is worth upgrading the volume potentiometer to a far superior Logarithmic type ALPS Blue Velvet 425G 100K x 2 audiophile grade potentiometers in your amp, (that includes your pre-amplifier if you have one) then let me just give you a clue about that.



The stock "El-cheapo" dual gang potentiometer which I presume to be a standard "linear" type due to the fact that the majority of volume input seems to be immediate at the early stages of volume control with the stock pot installed in the ToriiMK3?  Just an assumption since this has always been the case, and I see no other explanation for it.

This always was a undesirable feature which was part of this amp in stock form. Whether or not the stock pot was a linear, or the proper logarithmic type as what it SHOULD be, it doesn't matter at this point. It was not good enough for this amp design and should not have been used.  That pot caused me concern from the beginning with induced noise and inconsistency between the channels.  Now I realize it was actually a major "bottle-neck" to the full potential of performance for this design all along from day one.

What matters is that I have finally replaced that undesirable potentiometer with a highly upgraded version which should have been installed into an amplifier of this caliber when it was built.  

The design and layout of the ToriiMK3 amplifier is excellent. Too bad that the majority of parts inside other than the transformers and WIMA coupling capacitors being the exception, are substandard. But I guess that leaves room for more expensive upgrades to drive the cost up in order to get the top level of performance this design will most definitely provide if the proper element of quality components are installed.  And of course, we can't make this model TOO good, or what model could possibly be a "newer" version which then promises better performance?  High grade parts cost money!



Okay, before anyone goes off the deep end in defense of the original ToriiMk3, let's put this into proper perspective to make my intention clear here.  Number One, It is not my intension to degrade the ToriiMK3 design, or to be insulting to the designer.  In no way is that my intention. If you take it that way, I apologize in advance.  What I AM trying to reflect on here is that even with the great ToriiMk3 as it came stock from the assembly build, and as well as everyone that owns one has such high regard for its sound quality, my point is what actually (hearing and understanding) the difference at which the "next-level" can bring to an already great amplifier makes.

Look, don't you think that Steve knows this difference in what can be accomplished from stock form to that of SUPER-AMP status if he was so inclined to offer it that way? Of course he does, and he may very well have ultra modified versions of the ToriiMK3 which stands at the top of the elite offerings out in the audiophile world with nothing to exceed that ceiling.


So with that said, just understand the point I am making about perceived quality, and what can be obtained if you know how to achieve this world class standing. It is not difficult to do if you know what you are doing and have some decent skills to pull it off.


It all started with a great design. I just took that design further with extreme advancements which placed this amplifier into a much higher status of reference quality. I could not have achieved this without a solid design which became the platform for higher achievement.


Just think of this as having two options. A standard Mustang GT with a generous degree of performance features, or advancing to an ultra-modified Shelby beast with enough performance features and power to snap the neck of the unsuspecting passenger. Gotta love those 1200 plus HP ratings.  Nothing like a supercharged, well designed performance engine to shake your nads up a bit.

 I  look at the Zenith and think of it as my "supercharged Shelby" version.  And then there is the Dodge SRT Challenger. Nothing more needs to be said. I love the feeling of a supercharged Hemi when it is time to put the hammer down.  Talk about exhilaration to the MAX!  And that is the way I like my audio system.  I am starting with a GT, and advancing into a Shelby by comparison with every step of the way that I build within my audio room. That is my goal, not just a dream, or simply small talk. I am focused on what I can achieve.

 

Let me tell you from confirmed experience within a professional grade acoustical setting, using premium source components and well mastered music, this amplifier very well SHOULD have been the LAST amplifier one would ever "want" OR "need" if the level of performance matched my completely modified, highly upgraded Torii-Zenith model today.


A logarithmic (log) taper is essential for volume control to align with the human ear's perception of loudness, often referred to as "Audio Taper".

The Blue-Velvet ALPS potentiometer is a world class highly respected Japanese audiophile grade design which IS "logarithmic".


Is that really a big deal you might ask?  Is it really going to make that much difference?  To answer that subjectively, this of course lends your perception of the gained improvement by way of your acoustical setting (this makes up to 50 percent or more of the perceived quality of your music), plus the level of other upgrades within your amplifier, plus an extremely important factor, the quality of your source along with the quality of your recording.  All of these factors are relevant as to the degree of "improvement" that you may actually perceive.


To put that in perspective, if you have terrible room acoustics, poorly set-up speaker positioning, incorrect seating position, a completely stock version of the ToriiMK3 amplifier, and a mediocre source such as a CD player using a op-amp output stage, playing a poorly recorded CD (especially todays "RE-MOLESTED" TITLES), then I would predict that your perceived level of "improvement" would be marginal at best, to maybe barely noticeable at all.  When you build a system and room at the level I have today, this level of improvement is FULLY presented for what difference it actually makes in the amplifier.



What level of improvement do I hear now with the new ALPS potentiometer installed as the final upgrade to the Torii-Zenith?

That's like asking how powerful is a 44 magnum compared to a 9mm pistol!  There is absolutely NO equivalence here what-so-ever.


*NOTE: I purposely left the stock potentiometer in place during the amplifier upgrade process for one very good reason.  Actually, two reasons, one being that if I encountered any unusual test results with something being amiss when I first applied power, I did not want this to be part of the problem.  TWO, my main reason, was to hear this amplifier with ALL of the major upgrades without changing the potentiometer, to actually understand the level of difference between the new ALPS, and the original dual gang pot.


My analysis: If one word could sum it all up into one tidy package of expression...that word would have to represent all that matters presented within the most glorious representation imaginable.  It brings a new perspective as to the meaning of "lucidity" within musical form.  In reality, there simply is no single word which can even begin to convey what I hear now with this final mod in place.  

Leaving that old mediocre potentiometer in place was a true bottle-neck, restricting me from hearing the true potential of my new Torii-Zenith design.  That bottle-neck is rectified now, and all I can say without reserve is that what I am enjoying is indeed on par with that description of being "the most glorious representation of music imaginable".  


No longer is the volume forced to the front which comes on full-strength at only 25 percent of the volume control. No longer do I have static or unusual anomalies which seem to drift as they once did from the stock potentiometer. No longer does this forced input create a "forced" unnatural form of attenuation.  All of this was not so apparent to me until I heard the new amplifier with the upgraded ALPS logarithmic design in place.  All I can say is WOW, what a difference it makes!

I do not sugar coat anything when it comes to audio. I do not hold back on what I truly perceive to be good or bad. I give it to you straight from my personal perspective, sometimes cold and hard, but as always, with true perspective as I see it. This is NOT an exaggeration or something that I "think" I may be hearing.....far from it. This is absolutely real and absolutely a gain with considerable impact.  You make up your own conclusion. But before you do, do as I did and actually prove it to yourself. There will be zero room for doubt remaining in your mind.  To hear it, is to believe it.


If anyone was able to hear my new amplifier build in my acoustical setting, there would be a whole new understanding as to the potential which the superb design of the Torii MK3 has in waiting.  I strongly recommend that anyone who still has a ToriiMK3, to perform the same or similar modifications which I did.  Everything I did was critical and important for which to achieve the outcome that I did.  If you understood my upgrades, I focused heavily upon multi-stages of high-quality bypassing in the power supply, focusing upon 1uf, 0.1uf,0.01uf, and 0.22uf bypass capacitors in the form of PIO, and MKP film and foil polypropylene types for superior control and sound quality.  This was all performed within a surgical approach at deep inner levels of advancement for optimal gain in sound purity and definition.

 Topping these off with those monster four pin TDK Epcos capacitors, coupled with 8uf Vishay types, this created a power supply which simply is at the top of it's class.  To finish off with high quality coupling capacitors, and extended bypassing within that signal inter-pass-stage feeding the signal tubes, the real dynamic edge of clarity and perception was fine tailored by the exquisite Russian military FT-3 Teflon capacitors, which have actual silver within their design.  These are the king of capacitors by any standard.  They are the ultimate touch for any high-end amplifier or preamplifier used in the signal output stage.  

And certainly, of the highest regard, the fact that ALL signal path wiring is upgraded to the highest grade possible of 7n silver plated copper-solid-core in a Teflon jacket is what defines the true ability for all of these components to shine in "light-speed" fashion.  The transient response of this amplifier now with these ultra-upgrades is something which is in very special territory for performance standards.  This amp is so fast it will make your head spin! The attack-and-decay rate is spectacular to say the least.



If you have the ability to solder and work with something that has high voltage potential inside, then there is no reason other than prying a measly $30.00 from your pocket and ordering the much superior ALPS unit to find out for yourself what has been missing here. If you heard the difference, there would be no question within your mind.  Stay away from low budget potentiometers...THEY SUCK!




If you decide to order a new amplifier, make sure that you spend the extra cash for the potentiometer upgrade from the beginning. What is even better, get a top notch stepped attenuator set-up for the ultimate performance.  Trust me, for the much lower cost, especially if you make this upgrade yourself, the actual cost is nothing compared to the gain that you will get out of it.  THAT IS NO FREAKIN JOKE! That is absolute reality.


Now I have a full-on need to take this system beyond the imaginable.  After hearing how huge of an advancement that the modifications brought forth into what is now the Zenith model, I must explore the possibility to where further advancements may go....doing it MY way.



This has changed my order of priorities for future builds and upgrades for which to accomplish my ultimate goal.  I am now prioritizing a custom dual-mono single-ended zero feedback design which has separate power supplies, separate dedicated R-core (custom-built) transformers, and separate signal stage sections to keep everything completely separated and fully isolated. The use of isolation transformers will be incorporated as well. I will be using extreme high-end film and foil capacitors with the main output capacitors being that of the fantastic Ag-Cu-Oil designs along with the superb Russian K75-24 film-and-foil models which are extremely dominant in what you hear in the outcome.  The parts list for this planned build to make a stellar dual-mono zero feedback preamplifier is VERY high in cost, and some parts are difficult to obtain now.  This concept would easily become a model which only people with very deep pockets can even consider if it were a retail model bearing a high-end audiophile nametag. But in the DIY world, and if built correctly with high quality standards, this can be obtained for what I estimate, around $1500 to $2000, depending upon the chassis configuration, the actual cosmetics, and the actual quality of the materials and the way they are implemented.


Why do I need a high-end pre-amplifier such as this?  Simple. Because my new DAC stage only outputs 0.65v RMS to the tube buffer stage, which is a unity-gain design. Being unity-gain, it does not increase the signal strength as it is passed on to the amplification stage.  I had two choices here. One is to install a dual 1:3 set of high-quality step-up transformers after the single-ended outputs of the DAC chip to bring this low output level up to almost a full 2.0v which the Torii-Zenith needs to produce full output power.  That would produce an effective solution with very good sound quality. But, for the ultimate solution, the preferred solution is to send these low-level signals into a high-quality pre-amplifier stage for super refined control and sound quality.


I am going full tilt all the way down the signal path in this system.  I am determined to make it the best it could conceivably be by any standard.  This is going to take some time, but nothing great ever comes easy or fast.  The new DAC design will complement all of this to the highest regard in build quality.


The very last component that I shall build from scratch is the modified C-9 holographic enhancement circuit. That goes to the back of the list with least importance for now.  When it finally comes about, everything will be full-circle, and I will have accomplished my objective.  Perhaps I will have a few good years remaining to enjoy all of this, but the point is, I WILL enjoy this without paying a fortune for it.  


I'm past the dreaming stage.  I'm going forward!

Now for some data concerning the path forward:




DAC Digital Decoder 24 Bit 192K Optical Fiber Coaxial Decoding Board CS8416+CS4344


24-BIT D/A, supports 16-24 BIT.

Sample rate reaches 192K, support 44.1K 48K 96K 192K.

Function:

-Optical fiber and coaxial digital signal input (optical fiber priority).

I WILL BE USING COAXIAL DUE TO IT BEING LESS PRONE TO JITTER ISSUES. THE SIGNAL TRANSFER IS MORE ACCURATE.

-Output stereo audio signal 0.65VA.




This is a minimalist DAC rated at 105db dynamic range with as few of parts involved as possible. A standard 16 bit CD is usually limited to 96db which can be dithered to 120db, therefore conforming to the frequency response of the human ear.

With that in mind, a 105db DAC has a signal to noise ratio which exceeds standard CD limitations of 96db. The higher 105db range provides for a clean reproduction with a maximum rate of 20 bit information. This places it in the range of HDCD playback, with all of it's dynamic range intact. The audio quality is preserved with the full dynamic potential which is meant to be heard on the HDCD format.

HDCD is a 16 bit encoding format which uses active peak extension and low level range extension features which raises the dynamic range to a estimated 20 bit range. Theoretically, this corresponds to a 120db maximum range.

Even though true HDCD is designed to use actual filters designed for this format, the fact is that most high end CD players that don't have the HDCD chips installed can still play back the HDCD format with the dynamic range it presents.


Since I require the ability to reproduce the dynamic range of HDCD encoded discs, and I have an extensive library of titles encoded in the HDCD format, this requirement must be met.

The Cirrus Logic CS8416+CS4344 24 Bit 192K Decoding Board satisfies my requirements very well, making it perfect for my application.

The CS4344 features a linear analog low pass filter plus a fourth order multi-bit Delta-Sigma modulator. This goes beyond the limitations of standard CD quality which is 16-bit/44.1kHz. The Redbook CD standard is considered as the threshold of transparency for audio reproduction. Considering the fact that the CS4344 is a 24-bit DAC, it is easy to understand that this easily goes well beyond the Redbook stage of 16 bits, placing it in the higher performance category where the HDCD format resides.

The noticeable sound quality is quite easily detected in music playback. This DAC converts low resolution signals by way of high sampling rates, thus ensuring that any quantization noise remains isolated beyond the human hearing range. Even with the demands of HDCD encoding, the end result equates to optimal, totally transparent playback with accuracy kept in check.


The CS4344 DAC provides single-ended output architecture. This is advantageous for direct interface with the external tube stage buffer. You have heard that "Less Is More" when it comes to circuit quality. There is much to be favored in that regard.

Not only do we have limited circuit complexity and far fewer parts for the signal to pass through, but what is critical is that "even-order" harmonics are preserved which can define what the "tube sound" is expected to be.



Just in case you need clarification on why "even-order-harmonics" are desired, that which comes naturally with "single-ended" designs, here are some points:


When you hear frequencies centered around even-integer-multiples of the fundamental frequency considered to be "even-order", this equates to a harmonic structure focused upon the 2nd,4th,6th,and so on.  This is where a sense of musical quality comes into play.

On the other hand, the opposite occurs with "odd-order" harmonics which are generally non-desirable.

With "even-order" harmonics, you perceive a smooth natural timbre as exactly that, a natural harmonizing of the fundamental signal.

 Another beneficial aspect is that during clipping of the audio waveform, there is differential treatment between the two halves being asymmetrical in form.



Single-ended circuits require minimal components in the signal path compared to balanced designs. By using this CS4344 DAC, this allows for an almost direct path to the tube buffer stage with clarity and definition intact, free of the extra coloration which would exist by use of phase splitters and differential amplifiers required for "balanced" operation.

When we look at the importance of harmonic structure, we think of why SET (Single-Ended-Triode) amplifiers are so well sought after due to their even order harmonics for which they are very capable of producing.

Why does this make it superior to have single ended outputs rather than "balanced"? Think about the statement I made clear in the previous paragraph.

Now come to the realization that balanced outputs are designed to cancel out even-order harmonics!  That just about sums up why "less-is-more" in this instance.

When you examine a design with "balanced" outputs, you will find that in order to do this, two signal paths carrying opposite polarities come into play which create a symmetrical transfer function. The result being that cancellation of non-symmetrical distortion eliminates even-order harmonics which we really want to hear in the music!

You may have a quiet background, but is it worth losing the most valuable part of the music structure which in essence, is the life-blood of the music?  Not me. That is why I will not be sold on the idea of balanced outputs. If proper grounding enforcement was utilized, backed by the use of 1:1 isolation transformers in the circuit, there would be zero need for balanced outputs anyway. Keep your audio cables short and forget about it.


Another benefit for using single-ended-outputs is that vacuum tubes are less prone to the critical need for being perfectly balanced, that which degrades by a large extent over time and usage, increasing the gap of critical matching to where they won't perform as well as they should when used in a balanced system. With the single ended design, there is far more forgiveness as tubes age and begin to degrade. As a result, there maintains far more stability over the life of the tubes which can be used considerably longer.


The CS4344 has "Pop-guard" technology built in which eliminates power-on clicks and pops, therefore utilizing a simplistic interface which reduces the need for external components otherwise required for coupling to a tube grid.


Another major feature is that it has direct drive capability. The output is a clean -95db THD+N with a 105db dynamic range. This easily provides a clean high resolution signal perfect for matching up to a high impedance input such as a tube stage.

The ONLY benefit the system gains by use of expensive, complex "balanced" systems is that of the gained noise rejection when using excessively long signal cables, along with a barrier against the formation of ground loops which otherwise may introduce ground noise in the circuit path. So, if you use reasonable length audio cables, and have 1:1 isolation transformers built into the circuit path, this is no longer an issue. In the final result, the single-ended design is always going to be superior in audio quality once the noise ratio is brought under control. It is a win-win situation as the most logical design to use if absolute music quality is your focus.


The MOFI X10D tube buffer is an improved upgrade design over the original Musical Fidelity X10D tube buffer design. The new version comes stock with 1N4007 series rectifier diodes in the power supply.  I will be upgrading these to high performance "Ultra-Fast" UF4007 diodes which has a profound effect upon limiting switching noise in the system.

The X10D rectifies the voltage input internally for energizing the tube heaters and high voltage power supply. The upgrade to "ultra-Fast" recovery diodes such as the UF4007 marks a noticeable improvement to sound quality with much tighter control. The specifications for the UF4007 are: Voltage Rating: 1000 Volts. Maximum DC Blocking Voltage: 1000 Volts. Forward Current: 1.0 Ampere. Reverse Recovery Time: Close to 75 ns.


To note: The DAC stage typically requires a buffer stage between it and the signals going out at the line level stage. This is typically done through op-amps which are mediocre for doing this task, leading to a hard edgy sound so typical of digital. The whole idea is to transform the digital bits into an analog form which must be formatted at this point to the best it is going to be if the overall sound character of the system is to be perceived as analog music, close to what it was before the analog to digital process was derived from the studio masters (typically analog tape). That is unless the original studio master was digitally mastered. Regardless, it began as a live analog source which is what we hear as normal.  

The main benefit of the single-ended output stage is that the "op-amps" have been deleted from the output buffer, along with all the other sound coloring components which are required for an op-amp stage to be effective.

So, what is usually done in order to produce a usable analog signal strong enough to pass on to the amplification stage, is to introduce a set of high quality step-up transformers typically around the 1:4 ratio + or -, that will increase the gain to a sufficient level for driving the next stage. In general,2V RMS is the standard for single-ended outputs, and 4V RMS for balanced XLR outputs @ 0 db FS.  FS = Full Scale which the 2v/4v standard refers to maximum output where the audio signal has reached the maximum digital level.

The alternative: use a preamplifier.

The majority of amplifiers out there are designed to reach maximum rated power using an input voltage of between 1 to 2 volts RMS. It really depends upon the design of the amplifier as to how it will respond to the actual voltage input. The Torii amplifiers do very well in this regard with very strong output based upon the 2v signal.  If the speakers are rated at 93db sensitivity or higher, then this is absolutely enough volume to satisfy anyone that has any sense to keep their hearing intact. If you doubt that a 25 WPC tube amp such as the Torii-Zenith can push the volume this intensely with strong dynamics, then bring your a** over here and I will correct your misunderstanding.


The Cirrus Logic CS8416 digital audio receiver supports sample rates up to 192 kHz. It provides eight channels of digital input data. The output produces extremely low jitter levels using a low-jitter clock recovery system which basically re-cleans and filters the incoming audio stream with a refined restoration process. The resulting jitter is an excellent 200ps, making it ideal for audiophile audio quality.


As I said, typically, the necessary approach yielding the best results are to use step-up transformers in place of the op-amp stage following the DAC single ended outputs. If the signal is too weak before sending out to the next stage, then the quality of the signal falls subject to distortion. Everything hinges upon impedance factors between the DAC output stage, and that of the tube buffer stage. The 24-bit/192kHz CS8416+CS4344 DAC module is generally sufficient to drive an outboard tube buffer stage directly, provided certain input impedance requirements are met.

Just keep this in mind: This DAC configuration is limited to a mere 0.65V RMS which is nowhere near the level it needs to be for a line level path for amplification.  We MUST provide gain here to increase the voltage preferably to a solid 2.0V RMS if the amplifier is to do its job correctly. In order to do this within audiophile standards in the purest form, there are two options, one which is most likely superior.  Those two options are high quality step-up transformers after the single ended outputs, or better yet, a high-end preamplifier which not only will provide the necessary gain, but also offer precise control before sending the signals into the amplifier. If you already have a preamplifier, then you have things under control with no further modifications needed.



This DAC board outputs a simple direct signal stream without the op-amp stage. The raw signal is compatible with the MOFI X10D buffer.

Tube stages typically present high input impedance ranging from 100kohms or higher. The CS4344 outputs a line-level analog signal which is rated @ 0.65V RMS (approximately 0.9V). This is much lower than the typical 2V RMS output of most CD players. A need for additional gain will be required in order to drive the amplifier to full power. The X10D is a unity-gain buffer, so it will not contribute to any significant degree of gain for the incoming signal.  That was the task for which the output transformers played the role of providing necessary gain to the signal. To gain a stronger signal, I would have installed a set of 1:3 step-up transformers as the gain stage, yielding an output of 1.95v instead of 0.65v RMS.


The DAC performance is characterized at a test load of 3kΩ. Providing that the tube stage input impedance is held much higher than this upwards of 100kohm or more, then the CS4344 will drive the load without distortion being problematic.


The X10-D tube buffer presents a high input impedance and a low output impedance, designed to act as a buffer between a source and an amplifier. The rated input impedance is 470kohms, with an output impedance less than 200 Ohms. Some reports have shown the output impedance to be as low as 26 ohms for what that is worth based on real world testing.


The X10D provides a consistent high impedance load to the source component, thus regulating varying impedance factors produced by amplifier inputs and interconnects.

The implementation of coupling capacitors is used to prevent DC offset from damaging or biasing the tube grid with negative impact.

The power supply design is critical for the performance of the CS4344 due to its sensitivity in order to remain stable.

The CS8416+CS4344 board is a perfect design for use as a digital-to-tube hybrid system. In most cases, the issue of signal gain will be under strong consideration.


Again, the X10-D is a unity-gain buffer designed for impedance matching, not amplification.





To be continued next post..............

And for some final thoughts and some insight to where this leads:




I just received a huge parts order where I managed to find authentic Japanese Nichicon Fine-Gold, Gold-Tune, and Super-Through electrolytic capacitors, along with a few ELNA Silmic II types for the power supply. These will also go into the high-end regulated Studer 900 power supply which powers the DAC board.

These esoteric audiophile grade capacitors are the best ever produced for electrolytics, with a high price tag to obtain them.  As for resistors, all are 1-percent-metal-film resistors by Dale/Vishay.

Of course, the electrolytics will all be bypassed with high quality PIO type capacitors as well as Wima and Vishay film and foil types in certain areas.  In critical areas, a few "Ag_Cu" polypropylene types will come into play for optimal sound quality.

I shall begin soldering the resistors and capacitors in place very soon after I get parts on order to build the dual mono zero feedback preamplifier. Should be next week. The remaining capacitors are mostly WIMA MKP and MKT types along with copper-foil-oil capacitors for the critical front end signal stage of the tube buffer. I will most likely pull the expensive copper-foil-oil 3.3uf main capacitors from the previous model DAC for use as primary output caps in this new X10D buffer board.

You would not believe how heavy this box of parts really is that goes into building this thing. When finished, it will be big and heavy.

Extensive bypassing will be done just as I did with the Torii-Zenith. Star grounding is a major aspect of this build to keep things very quiet in the background. Of course, this too will have power supply filtering directly as the power enters the unit to filter out EMI/RFI garbage.

In addition, 1:1 isolation transformers along with a soft start circuit will be included.  All transformers are high quality R-core types with shielding.  All internal wiring will be solid 7n silver/copper core heavy gauge wire. The solder used is premium Cardas Quad Eutectic Silver based, along with rosin flux to make high quality joints with excellent conductivity for the signals to pass.  This stuff flows like a dream.

Then once those units are finished, I shall begin building this new pre-amplifier.  


I like to have some time go by to think about things before I make it final.  We all know that nothing is ever final except for death.

So we shall see.


The most important thing about it, I will get my clean and accurate 2.0V signal that the amplifier demands. Most importantly, this being that I have a solid high-end DAC buffer stage which will be preserved and not compromised. What would be the point of this if that were to happen anyway! With a single-ended design free of op-amps, this is the way to go.


At least this is my opinion, and I'm sticking to it.

Of course, all things are subject to change.



Next, I shall show you a few images relating to my upcoming MOFI X10d upgraded tube buffer stage. This will mark the beginning of this stage.


Hope you get something out of this if not just something to pass the time away.