Mojo Audio Mystique EVO

Hi Everyone.

Benjamin here: owner of Mojo Audio and designer of the Mystique series of DACs.

I wanted to clear up a few things and respond to some of the questions that were asked.

First of all, the difference between our Mystique v1, v2, v3, and EVO:
The v1 and v2 use the same chassis and very similar ciruits. The big difference is the v1 had a direct-coupled output stage from the 18-bit AD1865 DAC chip’s voltage output with no external parts and the v2 uses the current output of the AD1865 with a discrete output stage that has two op amp stages per channel. The same output stage circuit used in our v3 and EVO.

In later versions of the v2, such as the v2+, v2SE, and our current v2X, the output stage uses the same discrete Sparkos op amps, Vishay TX2575 "Nude" resistors, and foil and film caps as our v3. Quite an improvement.

Our new v2X uses an XMOS USB input module that not only makes it more compatible with more operating systems, it also improves performance quite a bit as well.

Our v3 and EVO use nearly identical circuits to the v2 but with the 20-bit AD1862, better signal path modules and parts, better shielding, better grounding, better mechanical resonance, and 5X LC choke-input power supplies vs the 2X capacitive input power supplies that are used in our v1 and v2 DACs.

Our EVO is basically the same circuit as our v3, but with upgrades to the USB input, S/PDIF input, analog output, shielding, grounding, and mechanical resonance. And where as the v3 has two circuit boards (PSU and signal) with one .25" thick ferrous shielding barrier between them the EVO has three circuit boards (PSU, digital, and analog) and has a second .25" thick ferrous shielding barrier between the digital and analog boards.

Sound quality wise the entry-level EVO Basic sounds better in all ways than our v3.

The EVO is also divided into three versions: Basic, B4B, and Pro. B4B stands for "Bang for the Buck" and is our recommendation to most of our customers. With each upgraded version there are "freebies" in terms of upgrade options, so it pays to buy the entry-level B4B over a Basic with all the upgrades, and it pays to buy the entry-level Pro vs a B4B with all the upgrades.

And of course the EVO is engineered to be upgraded at any time in the future with better digital and analog signal path part options, advanced shielding material options, advanced anti-resonance options, better wiring and connector options, better AC filter options, and significantly better power supply options.

We’re already planning entirely new digital, analog, and PSU boards for the future with significant performance upgrades. And all of those boards will fit in our current EVO chassis.

The big performance upgrade would be to upgrade the chokes in the analog power supplies to the Lundahl or Lundahl amorphous core. That is where the "magic" comes from. It would be nice if some of you guys who upgraded your v3 or EVO with the Lundahl chokes could chime in and describe what you are hearing.

Of course both the analog signal path upgrade and Lundahl chokes in the analog section are included in the B4B, along with a few freebee upgrades.

We often get v2s traded in that will show up on the Specials page of our website. We rarely get any v3s traded in. When we get a v3 traded in it is usually pre-sold before we even post it on our Special’s page.

When we get trade ins we bench test them and adjust the trim pots for DC offset and MSB at the zero crossing (DAC chip linearity). Few companies who use the same DAC chips and op amps use these fine tune circuits even though they are on the data sheets of all the R-2R DAC chips and op amps we use. Something to think about.

When we resell used gear it comes with our standard 45-day no-risk audition, 90-day full-value upgrade, infinite trade in options, and a 2-year factory warranty. Our new gear comes with all the same return and upgrade options plus a 5-year warranty.
We usually resell our trade ins for what we pay our custom for them...sort of a discount to our loyal customers. We’ve been offering customers $3,500-$4,500 trade in on v3 DACs depending on version and condition. At $3,500-$4,500 we have a long waiting list to buy a used v3 from us.

So if anyone has a v3 DAC in good condition they want to sell for $2,600 no need to spend $$$ on a listing...I’ll be happy to buy it from you, recondition it, and resell it for $3,500 :^)

The most important thing to remember is the DAC can only give you what you feed it from your digital source. We get customers all the time who have a modest transport or server/streamer and want to buy one of the more expensive versions of our EVO: big waste of $$$. You want to use a digital source that is proportional to your DAC or all your DAC is going to reveal are the flaws in your digital source.

Remember when you could buy a CDP or a transport and DAC and the transports cost roughly the same price as the matching DAC? So we don’t suggest buying anything more expensive than our EVO Basic unless if you have a transport or server that costs over $5K. We would strongly recommend upgrading your digital source first.

And our advanced shielding and anti-resonance options will make very little improvement unless your entire system is of a high enough performance and is using similar shielding and anti-resonant products. So rather than buying a set of Stillpoints Ultra II feet for your EVO we might suggest you spend a similar amount of $$$ to buy Stillpoints Ultra Minis for your entire system if you don’t already have something equivalent.

BTW, we are about to run a few specials with freebees thrown in on our EVO between now and the first of the year. If you want to know about those specials sign up for our e-newsletter. They won’t be advertised anywhere else.

FYI, on January 1st we’re planning on raising the price of our EVO by $500 to compensate for rising parts costs. So it would really pay to purchase one before December 31st.

I hope you all found this helpful.

Feel free to call me if you have any more questions.

I would like to know if anyone has tinkered with the ground lift and ground post in Mojo Audio products. What were your findings?

After about a month of having the EVO, one morning I heard a significant hum out of my speakers.  

I changed the position of the ground switch on the EVO and that fixed it. I couldn't tell you what the original and current position is, but I can look if you need that info.

No idea what caused this - my house is 55 years old and probably has the original wiring.   

From Mojo Website:  "To optimize system integration the DC signal ground can be floated from the AC, Earth, and chassis grounds with the flip of a switch."

Ideally, a system should have only one ground point to the mains through one mains lead. Because you can get small earth loops happening if everything has a mains earth plug
All equipment are grounded to each other via the interconnects from source to poweramp if the power amp has the earth to the mains.
  
The only time a second mains earth is needed is if cd transport using the optical (toslink) connection to the dac. Then the transport need to have a mains earth as well.

Cheers George 

Actually ground loops occur when one or more components have a different ground potential.

Then the grounds seek to equalize themselves between the components through the path of least resistance, which is most often your low-impedance analog interconnects.

If all the components were at the same ground potential it wouldn’t matter if they were star grounded, daisy chained, or grounds floating, relative to each other.

The ground lift isolates AC/chassis/Earth grounds from the sensitive DC ground in the EVOs circuit boards, and from the signal that runs through the connectors to the interconnects.

And the grounding post provides the option to create a path of lower resistance between components than the AC safety ground in your power cables or your interconnects.

For advanced system grounding I recommend using the same 24AWG OCC UniCrystal silver wire we use in our digital and analog signal path upgrades. That would create the lowest impedance ground you could get. Ideally you would do this with all of your components and then star ground all of the grounding posts together at the AC safety ground at one of your wall receptacles.

I recommend connecting to the screw that holds the face plate on that receptacle and replacing the screw with a pure copper screw.

This will create a path of least resistance between all the AC grounds in your system and not only eliminate ground loops, but also actually lower the noise floor in your entire system.

All the best custom systems I’ve heard...ones owned by the most advanced DIYers I know...ones you can’t buy for love or $$$...use a dedicated OCC UniCrystal silver star ground between components.

Then you may be asking "what about the resistance of that brass grounding post on the EVO...it make no sense to use silver wire with that in the ground path" and you would be correct.

I’ve been looking for a low impedance grounding post for an EVO grounding upgrade option and I can’t find a copper one let alone a silver one.

I’m actually considering using a Furutech low-mass RCA plug in place of the brass ground post for customers who want to do advanced system grounding.

We already use silver plated wire in a low-impedance daisy chain between our AC/chassis/Earth ground star ground point located near the grounding post in the EVO and the shielding grounds on the balanced connectors in the EVO, and the shielding barriers between the circuit boards in the EVO.
And when you get our copper clad shielding upgrade both of the .25" thick ferrous shielding barriers are laminated with pure copper foil so that any EMI or RFI that contact the shielding barriers is dumped through the low-impedance copper foil, to the silver plated daisy chain wire, to the the grounding star point and grounding post.

As part of our advanced grounding upgrade not only will you get a low-impedance grounding post/connector, the silver plated wire in the daisy chain and the wire going from the ground star to the grounding post/connector will be upgraded to the same OCC UniCrystal silver wire I’m recommending to use between your components in your system star ground.

At Mojo Audio we take grounding and shielding very seriously :^P