Six DAC Comparison

@brbrock - 

Do you notice a Tube sound or 2nd order harmonics with the Helene and does the tubes give it a different sound than the Mojo Audio DACs.  

No particular “tubey” sound, as in overly warm or soft.  However, it does have a tubed output stage and tubed rectification.  Maybe a bit more “3D” than some solid state DACs, but that could also be for other reasons.  Also, consider the user-adjustable tube bias allows some customization of the sonic characteristics you will hear.

The way Aries Cerat  uses the R2R chips they say makes them extremely dynamic have you noticed this?  How detailed are they?  

It uses multiple AD1865 chips which, as discussed here in an earlier post, display a little more vibrancy and dynamic inpact compared to their sibling AD1862 chips used in previous Mojo Audio DACs, which offer more of a rich tone and organic musicality.  At least some hear those varying characteristics.  The use of multiple chips is a design choice that goes way back (my Monarchy DAC from the 2000’s had an upgrade that included piggybacking the PCM63 chips) but not all designers (like Benjamin) believe the trade-offs are worthwhile.

I have previously tried to touch on the differences between the Helene and both the X NCZ and the Z NC and, while not huge in my system, the characteristics I heard generally boiled down to the illusion of slightly greater clarity, less warmth in the mid-bass frequencies, and the same organically natural sound I hear from the Mojo Audio DACs, but even more so.

Sorry to bombard you with all these question.  

No problem.

Since I am sort of done with DAC comparisons for now, I have only two DACs in my system, the solid state SMc Audio DAC-2 GT-24 that I can leave powered up all the time, and the tubed Aries Cerat Helene that I will listen to occasionally when I feel like warming up the tubes.

In the process of moving things around to optimize the space on my racks, I found that the Totaldac GIGAFILTER USB cable that I was using between my Sonore streamer and Singxer SU-6 DDC was not long enough to allow me to place the streamer and DDC on different shelves.  In rummaging around, I found a Singxer UIP1 PRO USB Isolation Processor (USB in and USB out).  I was able to run my Network Acoustics Muon USB cable out of the Sonore streamer and into the UIP1 Pro (that sits on a different shelf) and then run the Totaldac GIGAFILTER USB cable between the UIP1 PRO and the SU-6 DDC (which are sitting next to each other on the same shelf). BTW, both the SU-6 and UIP1 are being powered by fairly high quality linear power supplies.

I started wondering whether it was a good idea to subject my digital signal to "all that stuff", so I asked Google AI; "can the Singxer UIP1 PRO USB Isolation Processor (high speed USB 2.0 purifier) be used in front of the Singxer SU-6 DDC?"

Here is what Google AI said:

"Absolutely yes! The Singxer UIP-1 Pro USB purifier is designed to go in front of a DDC like the Singxer SU-6 (or any DAC/DDC), acting as a crucial noise filter to deliver a much cleaner USB signal to your audio device for improved sound quality. You’d connect your computer (i.e., streamer) to the UIP-1 Pro’s USB-B input, then connect the UIP-1 Pro’s USB-A output to the SU-6’s USB input, providing a purified, isolated USB signal." 

Here’s how the setup works:

1. Source (Computer/Laptop/Streamer): Connects to the UIP-1 Pro via USB.
2. Singxer UIP-1 Pro: Cleans the USB signal, removes jitter and noise, and provides a clean, isolated 5V power.
3. Singxer SU-6 DDC: Receives the purified USB signal from the UIP-1 Pro and converts it to other digital formats (like I2S, Coaxial, AES/EBU) for your DAC. 

Benefits of this setup:

• Noise Reduction: Isolates your audio chain from the noisy USB power and ground from your computer.
• Jitter Removal: Re-clocks and reshapes the USB data, reducing timing errors.
• Better Sound: Results in a clearer, more detailed, and musical audio presentation. 

"So, it’s not just possible; it’s the intended use case for the UIP-1 Pro to enhance the performance of devices like the SU-6. "

Beyond the power of suggestion prompted by the AI response, I cannot be sure I am actually hearing a difference but, things seem a little bit quieter and more relaxed with that extra device (the UIP-1 Pro) in the signal path. It allows me to spread out my digital gear and still have the Totaldac GIGAFILTER USB just before the DDC so I will likely keep things this way, at least for a while.

@ saeed79

I’m sorry to hear that you had a bad experience with one of our DACs that you purchased used. 

There is most definitely something wrong with that DAC.

And nothing that we’ve ever had a customer report to us.

Though it is rare, over the past 15 years we’ve had some warranty repairs. 

The problem was always one or both channels being 100% dead.

We’ve never had a warranty repair where one channel was weak or bass was weak or some such. 100% dead or 100% working properly. 

We’ve had a few reports over the years of people who purchased one of our DACs from a 3rd party reseller like TMR who had an issue with them.

My guess is somebody messed with them who didn't know what they were doing. They could have adjusted the DAC chips MSB or op amps DC offset incorrectly. 

That being said, TMR is a very good company...I buy gear from them all the time.

But they don’t know how to properly test and adjust the fine-tune trim pots in our DACs.

BTW, with our new Z being released we’ve swapped out Zs for Xs with the various speaker companies who use our DACs in demos and at audio shows. 

Like most companies, on 1/1/26 we have to pay taxes on our inventory. 

We would rather give a customer a great deal than to pay taxes on those demo X’25 NC DACs.

If anyone is interested in a crazy low end-of-year price on a used or demo DAC please contact us.

Thank you all for the replies. I’ve started the return process with TMR, and they have been very helpful and understanding.

Regarding the DAC, I purchased it from eBay in the USA, and I am currently located in Saudi Arabia. I switched the internal voltage selector from 110V to 220V, so it’s possible that their testing did not reveal any issues when the unit was operating at 110V.

I measured the output myself, and the difference is very clear: there is a 4–5 dB channel imbalance between the left and right channels.

As for the sound, I couldn’t fully evaluate it due to the issue, but in terms of timbre it sounds very pleasing and colorful. It has the warmth of copper combined with the precision of silver. My current DAC lacks that level of precision, which is something I really appreciated with the Mojo.

I’m now considering the new Z model. My Mojo X is the AM version, I’m leaning toward the lower Fe model for more warmth and a softer bass attack. I’m wondering if this assumption is correct.

"I’m leaning toward the lower Fe model for more warmth and a softer bass attack. I’m wondering if this assumption is correct."

@saeed79 - 

From Mojo Audio’s website:

"With each choke upgrade you get more micro-details and micro-dynamics, a more ethereal top end, a more luscious midrange, more textured and tuneful bass, better musical flow, and more engaging emotional expression."

I have had all three types of chokes in Mojo Audio DACs and I wouldn’t argue with the conclusions presented by AI below.  I would also add that I found the amorphous chokes a worthwhile overall upgrade from ferrous core chokes while the choice between amorphous vs. nanocrystal chokes is more about personal preference.  For a more detailed explanation, you could always discuss this with Benjamin at Mojo Audio,  who has been open about the differences he hears.

From AI:

The core material affects how the power supply delivers current, which in turn influences the sonic presentation.

• Ferrous Core (Entry Level): This core provides more "gestalt and slam" to the sound, with a more energetic and exciting presentation. It has a robust, impactful sound, though some reviewers note it can be slightly less subtle or textured compared to the higher tiers.
• Amorphous Core (Upgrade): The amorphous core provides an intermediate step, offering more micro-details, micro-dynamics, and a more pronounced texture than the ferrous core. The sound has a slightly lower sine wave energy representation (per Mojo Audio’s analogy), which translates to more nuances and more refined textures in the audio reproduction.
• Nanocrystal Core (Top Tier): This is the top-of-the-line option and offers the greatest refinement. The nanocrystal core provides the most profound sound quality, with a very low noise floor that allows for subtle and complex harmonic details to become apparent. The sound is more relaxed, with better timing, tune, harmonic structure, and overall musical flow, leading to more engaging emotional expression. It provides the best resolution and the most natural timbre, bringing the listener closer to an analog, vinyl-like experience.

In summary, as you move from ferrous to amorphous to nanocrystal cores, the sound signature becomes less "digital" and more organic, with increased resolution, better harmonic coherence, and a more natural, emotionally engaging presentation. The fundamental energy remains the same, but it is delivered with greater texture and nuance with the advanced core materials.