MicroZOTL2 Upgrade Discovery Thread.....

[drbluenewmexico]

Mojo-Audio has successfully upgraded the performance of the recently reengineered MicroZOTL tube headphone amp by David Berning and Linear Audio.  the upgrades are receiving a lot of discussion on MicroZOTL2 thread, and now deserve their own thread and discussion group.
 
The upgrades head Mojo Benjamin Zwickel has done and will show you on this thread include:
Ultralow-noise linear power supply upgrades, DC power cable upgrades, lower noise grounding schemas, headphone or preamp optimizing, single input modification, multiple output modifications, anti-resonant treatments, high-performance fuse replacements, upgraded wiring, upgraded connectors, upgraded attenuators, upgrade capacitors, 4-pin XLR “balanced” headphone output, 3-pin XLR “balanced” input, and more to come. 
 
I am moderating this thread and facilitating the contributions, so please help me by keeping them relevant to this topic. 
I have one of the first prototypes of the new ZOTL2, and Ben has upgraded it for me and it has quite a bit of play time on it
and is fully  burned in.  Im running it off a Mojo Joule v5 power supply fed and streaming TIDAL into a Mojo Mystique 1 DAC with
MOJO audio cables, etc.  it is a stunning system, and i use it as a preamp into near field Foxtex subwoofered monitors for
room play. I am using it primarily with Foster XX0 Mahogany headphones, well burned in, as well as other top end headphones.
I love the sound, and offered to help Ben get his own personal upgraded ZOTL2 out on tour so the community of audiophiles
could experience its sonic signature.
 
Benjamin will be posting updated instructions for DIYers to upgrade their own microZOTL2, including what parts he considers high value and what parts he considers high-performance. Also, Benjamin will include photos of upgrades he’s done to different customer’s microZOTL2s with descriptions of what was done so that DIYers can follow his “recipes.”
Please use this thread to comment on upgrades you have performed, heard of, or plan to do to your ZOTL2 tube headphone amp.
 
NOTE: this is not an advertisement thread and I want to keep it clean. 
Benjamin has kindly offered to GIVE AWAY all of his microZOTL2 upgrading secrets. Feel free to ask Benjamin any questions pertaining to DIY upgrades. If you have any questions for Benjamin regarding pricing for him to do upgrades for you or want his opinions as to how he might compare products manufactured by Mojo Audio to competitors products please contact Benjamin off thread through the Head-Fi email system or preferably directly through Mojo Audio’s website. 
 
To save DIYers time and trouble, Benjamin will soon be offering microZOTL2 upgrade kits for DIYer that include many of the parts he recommends. If you want information on DIY upgrading kits or you are interested in purchasing parts for DIY upgrades please contact Benjamin off this thread. 
 
There are many other companies that have products and processes for upgrading the microZOTL2 other than Benjamin and Mojo Audio. We welcome any and all of you to share informative posts. Any posts that break Head-Fi policies toward members of the industry advertising or conducting business on forum will be deleted and the posters will be warned. Repeat violators will be banned from this thread. 
 
I look forward to your input!!!! drbluenewmexico

 

[drbluenewmexico]

Im having audio sadness. I had to return the first production Mojo Illuminati power supply to them for audition touring.
I'M back to my old Joule V5 power supply. its no slouch, and sounds great, but the effect the Illuminati power supply had on the
upgraded MicroZOTL2 was astounding, the near field Foster speakers (usually the ZOTL2 as a preamp) just disappeared,
and i was left with a floating sound field of holographic proportions.  The Foster X00 headphones became 3D and the soundstage
became wider, more dynamic and full of more "musicality". i was truly spoiled by the positive synchronicity of the
Illuminati and the upgraded MicroZOTL2.....
 
The upgraded ZOTL2 still sounds fabulous as a headphone amp and preamp, buts its nice to know the headroom for improvement
continues to expand! this amazing amp seems to have few limits to how good it can get with increased excellence in the chain
of power, source signal, cables, etc.  the sky seems to be the limit....

 

[yukihasi]

First I want to thank Ben for all his advice to me through the whole upgrading process, he has the enthusiasm to his job and audiophile, and most of all he makes great products! 

 
As I mentioned in the main thread I sent my mzotl to Ben and got literally all the best possible upgrades he had on it, such as rewiring with mono crystal silver wire, stillspoint standoffs and feet, replacing RCA input with furutech XLR, illuminati power supply, etc etc. Please pm him for details about what he has to offer. 
 
When I finally received the upgraded mzotl with Joule V5, I immediately noticed that the improvement is in every aspect that I can think of without bringing anything "unpleasant" to the sound. Which is the problem I have most of the time upgrading gears, had improvement in A but had set back in B, then I get more upgrades and lost track with money flying away...
 
With Ben's upgrade and power supply there is none of that, you might not believe it, but the reason to it is the improvement was in transparency. Transparency is the best thing in audiophile, you hear more nuance, more low level details you never noticed before and instrument became easily distinguished/separated, more resolution, hence music is "flowing" easier, which some people may refer as "musicality". IMO this is achieved by kicking out the noise and distortions using premium components. 
 
I had the stock power supply and LTA linear power supply before the upgrade. From stock to LTA linear power supply, the bass has the most improvement, and there are other improvement in mass and "presentness". If you feel that the mzotl sounds thin in your system, the LTA LPS will worth it.
 
Unfortunately I cannot compare the LTA LPS directly to Joule v5 and illuminati since I asked Ben to hard wire his power supply connector cable to my mzotl so it's no longer compatible with stock and LTA LPS (now has 4-pin XLR connector to mojo audio PS instead of DC connector). 
So the differences I hear after the upgrade is stock mzotl + LTA LPS v upgraded mztol + Joule v5. 
 
And then I received the illuminati last weekend. Compared to Joule v5, sound stage expanded and instrument placement became more precise while not sacrificing much mass of each instrument. Resolution boosted while still staying musical, instrument became more real life sounding. Joule v5 sounds like there is still something between you and the sound, aka blurry. That is actually not a bad thing in some case since it gives you some warmth. But with illuminati, there is finally nothing to hide in the music, you get to see each and every thing like they were there in the room and revealing a whole lot more details.  
 
One last thing to mention, after the transparency improved like this, tube rolling will make more difference since the mzotl became more "sensitive". The same thing applies to other part of the system, make sure they have the potential to feed good signals to mzotl, and then you will never have to look back 

 

 

[MojoAudio]

  Unfortunately I cannot compare the LTA LPS directly to Joule v5 and illuminati since I asked Ben to hard wire his power supply connector cable to my mzotl so it's no longer compatible with stock and LTA LPS (now has 4-pin XLR connector to mojo audio PS instead of DC connector).

 
If anyone wants to compare their LTA LPS with one of our power supplies after getting an upgrade like that we could always make them a short adapter cable that would convert the stock mZ2 power supply connector to our 4-pin hardwired DC power cable.
 
Below are photos of yukihasi's upgraded mZ2.
 
In addition to the UniCrystal silver wire he also had our hardwired DC power cable, 105C capacitor upgrade, Thermistor fuse upgrade, 47-step Goldpoint attentuator, Stillpoints anti-resonance feet outside, Stillpoints anti-resonance standoffs inside, and B-Quite anti-resonance sheeting applied to the chassis.
 
He even had us install Furutech XLR connectors at the input. They are not true balanced inputs, but they are considerably better than using a cheap balanced to SE adapter.
We call this an "EXTREME" upgrade...pretty much what I'm doing to my personal mZ2

 
I'll be posting DIY instructions for this upgrade in several parts over the next month or three.
 

 

[EdmontonCanuck]

Just shipped off my MZ2 to Ben today for the "Extreme" upgrades along with the Illuminati. I'm super stoked to hear what it will sound like when I get it back!

 

[drbluenewmexico]

You are in for triple treat ma
Each device and their amazing interaction!

 

[yukihasi]

Had some more comparison between Joule V5 and Illuminati. When I got Joule V5 I thought this is already so good that I wonder what else can be improved. It becomes easy to answer that question after I used Illuminati for a while and then went back to Joule V5. I certainly see why Dr.Blue is so sad not having Illuminati around 

 
Basically, all the goods Joule v5 did to the mzotl, Illuminati just did better.
1. Further extended high and bass freq.
2. Superb separation
3. More details from improved clarity and transparency. 
4. More emotion/nuance in vocals and instruments revealed.
...all these brought the sound closer to real life.
 
Thanks again to Ben for letting me keep the Joule V5 for a while longer to compare it with Illuminati. Mission complete and Joule V5 can travel back to home 

 

[drbluenewmexico]

  Had some more comparison between Joule V5 and Illuminati. When I got Joule V5 I thought this is already so good that I wonder what else can be improved. It becomes easy to answer that question after I used Illuminati for a while and then went back to Joule V5. I certainly see why Dr.Blue is so sad not having Illuminati around 

 
Basically, all the goods Joule v5 did to the mzotl, Illuminati just did better.
1. Further extended high and bass freq.
2. Superb separation
3. More details from improved clarity and transparency. 
4. More emotion/nuance in vocals and instruments revealed.
...all these brought the sound closer to real life.
 
Thanks again to Ben for letting me keep the Joule V5 for a while longer to compare it with Illuminati. Mission complete and Joule V5 can travel back to home 

Thanks for your follow up observations @yukihasi   I am sad about drop back in performance to the Joule v5 power supply from the Illuminati going bye bye.  But the Joule v5 is really good also, and once i get into the music i can live with it.  If ones wallet wasn't flush enough to deal with an Illuminati upgrade the Joule v5 would be a superb improvement in most systems to drive the ZOTL2 or its relatives....still once you get used to excellence its hard to go back, thats the danger and excitement of listening to state of the art electronics.....that really do what they promise......whats exciting is how much information is still in the signal of the Mystique v1 dac transmission, ready to be revealed! currently Mojo is selling a v2+ and they expect to be releasing a v3 in early 2017. I will  be getting a v2+ to review in the near future to make direct comparisons to my v1 and I am  on the short list to audition a v3 pre-production late ’16 or early ’17. Very excited to hear the upgrade Dac's!

 

[saidentary]

  Just shipped off my MZ2 to Ben today for the "Extreme" upgrades along with the Illuminati. I'm super stoked to hear what it will sound like when I get it back!

IS IT BACK YET???  If so, what are your impressions?????????  Just askin'
.

 

[EdmontonCanuck]

 
IS IT BACK YET???  If so, what are your impressions?????????  Just askin'
.

 
Lol, no. International ground shipping from Canada to Albuquerque took 10 days (I think the Labour Day holiday added a day or two to that trip). It arrives there today. Ben indicated he would need it for 2-3 days, then I'm assuming it will take an additional 10 days to get back to me up here in Edmonton. I really hope it gets here in time for me to take the combo down to Calgary for a Head-Fi meetup on Sept. 25th. Ben said he didn't think that would be a problem, and he has graciously agreed to burn in my Illuminati for me while he's been waiting for my ZOTL2 to arrive, and to also give the upgraded ZOTL2 some burn-in before shipping it back to me.

 

[dpump]

 Like to get the specs for the upgraded fuse you are using.

 

[MojoAudio]

   Like to get the specs for the upgraded fuse you are using.

 
Instead of a fuse we replace the fuse holder on the PCB with a self-resetting Thermistor.
 
This is a <$1 part that performs better than any high priced audiophile fuse.
 
We're using the RHEF400 from Mouser.
 
Mouser part number: 650-RHEF400
 

 
A Thermistor is a resistor that is current/temperature sensitive.
 
When it is within the proper operating range it has a low fixed resistance (~4 to 20 ohms).
 
When the current flow is above a certain point the resistance of the Thermistor goes up until it is so high that no current can pass (equal to blowing a fuse).
 
Once you turn the component off and allow the Thermistor to cool it will automatically return to it's low fixed resistance.
 
We use Thermistors in our Illuminati
 

BTW, if you have a bit of DIY experience and can do the math, you can upgrade just about any fuse on just about any component with a Thermistor

 

 

[zachawry]

I can't wait to get my Illuminati back from Ben.

I'm having him ship it with my new Mystique DAC, and all I can say about that is, if you don't want to buy it, don't try it!
Going back to my Hugo was like having a veil pulled back over the music.

One downside of having a modded MZ2 is that I can't listen to it with my old LPS. Not that I anticipate ever having to send my Illuminati back, though....

 

[MojoAudio]

Capacitor Upgrade
 
As long as you have the PCB out of your mZ2, and your soldering/de-solder tools out, you might as well upgrade the power supply capacitors.
 
When upgrading capacitors you need to make sure of the following things:
 
1. They fit in the same space on the PCB.
2. The leads on the caps fit through the same holes on the PCB.
3. They have the same or higher voltage than the original caps.
4. They have the same or higher value than the original caps.
5. They have the same or higher temperature rating than the original caps.
 
These rules apply to upgrading caps on any component.
 
It is important to make certain that the caps that are near the tubes are not considerably taller than the original caps so that they don't get excessively hot in use.
 
I know some of you are thinking "what about audiophile grade caps?"
 
Truth be told, some are better and most are not as good as higher grade commercial caps that meet the above criteria.
 
Temperature ratings are based on hours in service at that specific temperature, which is a good indication of overall capacitor life. The original caps in the mZ2 have an 85C temperature rating. We use caps with a higher 105C temperature ratings as well as higher hour ratings.
 
In addition to longer life, all the caps we recommend have higher degrees of ripple rejection, resulting in an overall lower noise floor for your mZ2.
 
Below is a photo of the stock mZ2 caps (top row) to compare to the upgrade caps I'm recommending (bottom row).
 

 
Diameter and lead spacing is the same, but some are taller.
 
Each line below has the quantity required in parenthesis, the capacitor manufacturer's part number, and the general specifications of the caps we recommend.
 
(1) EKY-500ETD100ME11D (10uf 50V 105C replacing a 10uf 50V 85C)

(1) UCS2W220MHD (22uf 450V 105C replacing a 22uf 450V 85C)
(1) EEU-FB1E102 (1,000uf 25V 105C replacing a 820uf 25V 85C)
(2) EEU-FC1C682 (6,800uf 16V 105C replacing 6,800uf 16V 85C)
(4) EEU-EB1V471B (470uf 35V 105C replacing 330uf 16V 85C)
 
Note that aside from the higher temperature ratings, most are identical in value and voltage to the original mZ2 caps.
 
Total cost of all the above capacitors is only about $10.
 
Also note that we did not replace the largest 22,000uf cap located right next to the fuse. First of all, we could not find a better cap that would fit in this same spot on the PCB. Secondly, when using a high-performance external power supply this cap becomes superfluous.
 
Below is a photo of the mZ2's PCB with all the upgraded caps installed.
 

 
This would also be a good time to upgrade the critical resistors in the signal path.
 
Since I've not finished my tests on the resistor upgrade, we'll have to save that for a future post.

 

[jamato8]

  Capacitor Upgrade
 
As long as you have the PCB out of your mZ2, and your soldering/de-solder tools out, you might as well upgrade the power supply capacitors.
 
When upgrading capacitors you need to make sure of the following things:
 
1. They fit in the same space on the PCB.
2. The leads on the caps fit through the same holes on the PCB.
3. They have the same or higher voltage than the original caps.
4. They have the same or higher value than the original caps.
5. They have the same or higher temperature rating than the original caps.
 
These rules apply to upgrading caps on any component.
 
It is important to make certain that the caps that are near the tubes are not considerably taller than the original caps so that they don't get excessively hot in use.
 
I know some of you are thinking "what about audiophile grade caps?"
 
Truth be told, some are better and most are not as good as higher grade commercial caps that meet the above criteria.
 
Temperature ratings are based on hours in service at that specific temperature, which is a good indication of overall capacitor life. The original caps in the mZ2 have an 85C temperature rating. We use caps with a higher 105C temperature ratings as well as higher hour ratings.
 
In addition to longer life, all the caps we recommend have higher degrees of ripple rejection, resulting in an overall lower noise floor for your mZ2.
 
Below is a photo of the stock mZ2 caps (top row) to compare to the upgrade caps I'm recommending (bottom row).
 

 
Diameter and lead spacing is the same, but some are taller.
 
Each line below has the quantity required in parenthesis, the capacitor manufacturer's part number, and the general specifications of the caps we recommend.
 
(1) EKY-500ETD100ME11D (10uf 50V 105C replacing a 10uf 50V 85C)
 
(1) UCS2W220MHD (22uf 450V 105C replacing a 22uf 450V 85C)
(1) EEU-FB1E102 (1,000uf 25V 105C replacing a 820uf 25V 85C)
(2) EEU-FC1C682 (6,800uf 16V 105C replacing 6,800uf 16V 85C)
(4) EEU-EB1V471B (470uf 35V 105C replacing 330uf 16V 85C)
 
Note that aside from the higher temperature ratings, most are identical in value and voltage to the original mZ2 caps.
 
Total cost of all the above capacitors is only about $10.
 
Also note that we did not replace the largest 22,000uf cap located right next to the fuse. First of all, we could not find a better cap that would fit in this same spot on the PCB. Secondly, when using a high-performance external power supply this cap becomes superfluous.
 
Below is a photo of the mZ2's PCB with all the upgraded caps installed.
 

 
This would also be a good time to upgrade the critical resistors in the signal path.
 
Since I've not finished my tests on the resistor upgrade, we'll have to save that for a future post.

Why do you believe these are better caps? Temp range and are the specs that much different or your experience with them and results? I will be interested to see what resistors you come up with.