Major EXOGAL Comet/Ion problems


Five years ago I bought an Exogal Comet to use as a DAC with my Rogue Medusa amplifier. It proved itself an excellent unit in all respects and I was positively impressed with the company's support and helpfulness. A year ago I bought the matching Exogal Ion amplifier (at considerable expense) to go with the Comet and was delighted. (The Medusa was wonderful but I wanted something with a smaller footprint). 

Reviewers have invariably criticized the Comet's diminutive window for being extremely difficult to read and the cheapness of the remote control. Noting these deficiencies, the TAS reviewer Vade Forrester (June 24, 2015) wrote, "I learned the Comet is really intended to be operated remotely from an iPhone or iTouch." My experience was that the window and remote were exercises in frustration, but that the Apple application I downloaded from the Exogal site for my iPad was ideal; I had total control over the unit and the app was a delight to use--very Space Age. For the record, I liked the Comet so much I unloaded my Rogue RP 1 and used it as a preamp. 

All was well until I got a new iPad and couldn't download the application. When I called Exogal I received a somewhat garbled account that Apple was no longer permitting them to use the application. Ditto with Android. After a while they announced a remote control module was being developed and in the pipeline. They sent me an experimental prototype that in my opinion wasn't much of an improvement over the original. On the few occasions I can reach them they say it will be ready in a week but weeks have passed. This is tantamount to having a fancy TV where it is a major struggle to perform a simple action like change the channels! 

Exogal is singularly uncommunicative about this problem. Their website is scarcely used and they seem to have moved over to Facebook. The strangest thing is that on the website they list under "Products" a series of four Vortex streamers, described in detail, that apparently were never manufactured! They don't answer their emails. They say their site has been hacked and various other things. In a rare new posting on their website and Facebook they claim the they have just opened a distributorship in Europe. This raises the question how are the European purchasers going to operate their units? None of this inspires consumer confidence.  

My point here is that when someone spends 7k and above on supposedly elite components they deserve responses and explanations. It is Exogal's responsibility to ascertain that these units are operable as designed. I have to question the business sense of relying on an outside entity like Apple that is notorious for being proprietary. It is totally unbusinesslike not to make a public explanation of these issues with a timetable to correct them. Customers should not have to go foraging around Audigon forums to learn what is, or isn't, happening. 

Now the window on the Comet periodically goes blank (it was never even illuminated). Having 7k worth of Exogal equipment that is extremely difficult to operate, I went and bought a Wyred 4 Sound integrated and a Black Ice DAC so I can actually listen to something without a struggle. The Exogal stuff is in a box waiting for who knows what. I am beginning to think that Exogal is indeed out of this galaxy, but for all the wrong reasons. This is very surprising because a couple of years ago they were exemplary in all respects. I would like to hear from other frustrated owners to see what solutions they have devised. 
128x128rtorchia

Hello,

Wadia 321 is an excellent DAC. With twin 321, are you running 2-way active digital crossover set up? 

Unfortunately, the 321 doesn't feature DigiMaster. 

You might be aware that Jeff Haagenstad and his team when they left Wadia and form Exogal, they decided to build what they have always wanted in a DAC, but were limited by the hardware processing power, at the time when the DigiMaster were developed at Wadia.  This is the Comet, essentially the next logical evolution from the DigiMaster, but leveraging the much improved huge processing power of the latest hardware technology. 

I shall do one step better than providing you with more details on the 'Calculus' approach.   

Here's an excellent white paper that details the Calculus approach towards deriving the upsampled data that dramatically improves the resolution power of the Exogal DAC. 

White paper :

Link 1:
https://www.dropbox.com/s/grjzqn24u3t1a11/EXOGAL-DAC-and-PowerDAC-White-Paper-Revised.pdf?dl=0

Link 2:
https://www.google.com/url?q=https://www.lowbeats.de/site/wp-content/uploads/2019/05/EXOGAL-DAC-and-PowerDAC-White-Paper-Revised.pdf&sa=U&ved=2ahUKEwjLmP2aj_P8AhWGRmwGHcY4DDsQFnoECAkQAg&usg=AOvVaw2Wgaf5CRdkTgqhW_6Y8rpL

User Discussion :

https://www.avforums.co.za/threads/exogal-comet-and-ion-using-calculus-to-determine-sound-not-steps.95426/


The brilliant aspect with Wadia's DigiMaster and now the Exogal's Calculus approach is that these techniques are based on analog functions that have the potentials to provide infinite resolution. Just like fractal geometry, the closer you look, the more details can be revealed. It is only limited by the hardware's processing power. 

From a practical application perspective, i would rather have a meaningful 24-bit 192khz PCM decoding, with tons of high resolution details that are cohesive in nature than some super high upsampled PCM that is meaningless, in terms of providing more resolution details, but was necessary to enable the use of digital filter, with a gentler rolloff slope, which imparts less digital artefacts.  You can read up on the white paper from PSAudio Directstream DAC and Chord Hugo M-Scaler. They are technically excellent, but if you read closely on the approach, there isn't much intelligence in deriving more detail and cohesion from the quantised data. 

I started with my audio hobby in the 1980's, when digital CD technology just started. We were lucky to have good exposure to high quality analog sound sources as well from great turntable setup to Nakamichi tape decks. And despite the hissing background and static clicks from these sources, there is definitely a sense of musicality they project, that is missing from the early digital sources. 

That is until i had the great pleasure of auditioning the Wadia DAC. First the Wadia 2000, then subsequently the majestic Wadia 7+9. Then later the Wadia 27ix. 

To me, the Wadia DAC's ability to convey a dynamic, yet musical sound has always been a major attraction aspect. The bass is phenomenonal. And the highs, has a very analog sounding quality with high resolving power. It's very believable.

The Wadia 121 is the last iteration that Wadia managed to squeeze all the combination of Wadia technologies into single DAC unit, including DigiMaster, before the company has changed ownership of Fine Sounds. 

Thereafter the newer DAC's are based on ESS Sabre, but no longer features DigiMaster, but still benefit from Wadia's proprietary analogue output stage innovations and technology. These are the Wadia 122, 321 and 322.
The great sound from these DAC has less dependency on the ESS Sabre DAC chip they use, but more so on the Wadia proprietary analog stage that follows. 
Don't get me wrong, these DACs still sounds amazingly good. 
If you set up the 122 in a manner to extract the very last detail from the 122, you would be more than impressed by how good it sounds. In this regards, the Wadia 122, IMO is the best sounding DAC in its price range. The 321 and 322 builds upon the 122 platform, with a much enhanced power supply that fortifies its earth shattering bass department with the visceral power to command total control. This makes a very notable improvement in a larger setup. This is the typical Wadia DAC forte, yet the highs are much better than the classic Wadia DAC's with more resolution and extension. 
Compared to the 122, the 322 sounds is more luxurious, it has an elevated sense of detail and embellishment. The sound stage is wider and dynamic content is more assertive and lifelike. It is very close to being an ideal DAC. 
The bass department is as perfect as i can ever hope for. 
The only small aspect i wished for, is an improvement in the ultra high frequency resolution. Without the DigiMaster, its hands are tied. Here, this is where the Exogal Comet shines. 

I have learnt in the past two decade that by resolving the high frequency properly, together with restoring the missing harmonics in the ultra high frequency range, this not only adds musicality but restores realism. When this happens, you can start to forget about the equipment and focus on the joy from music. 

It may sound like an easy goal. But finding a DAC that provides the most analog sounding property is no easy task. Wadia and Exogal are the two great examples, dCS is another. And the other challenge is to find an amp circuit that has ultra high bandwidth that can resolve all these details in high accuracy and coherence. This is where the Goldmund Job4 1Mhz bandwidth comes into play. There are a few different implementations of the Goldmund Job4 in various disguises, obviously the Goldmund, but there are Stellavox, Job Amp and even Nuforce STA200. If you combine these two elements(Wadia/Exogal Comet + Goldmund Job4) suddenly you will start to experience true musical 'magic'! 

Throw in a crossover approach that focuses on preserving the absolute signal integrity by operating in the digital domain, suddenly everything just clicks, and you have a system that would provide everything you can possibly hope for, as this system would finally be free from all the typical distortion and limitations that are responsible for holding back most other setup, as they continue to battle the various challenges in the analog signal path. 

I run twin Wadia 322 DAC in my main set up and now introducing the Exogal Comet. 

For Wadia 322 runs the high frequency and the other for low frequency, in a fully active digital crossover setup, utilising a DEQX HDP-3 operating in digital domain with the optional digital IO card. All my front end is managed by a Goldmund SR8 Digital Universal Preamp, which process all signals in 24-bit 96kHz PCM. 

My main transport is a Esoteric X01 Limited. 

Streaming is from a iFi Zen Stream. 

Both DEQX and Goldmund SR8 are limited to 24bit 96khz. 

Since the system needs support for the Pioneer TAD PT-R9 Beryllium Ultra high frequency reproduction in the 120kHz region, which augments the JBL Project K2, i need to upsample the PCM to 24bit 192khz to meet the Nyquist frequency requirements and get the sound reproduction close to the 96khz. 

To ensure clock accuracy, the upsampling to 192khz is performed by the brilliant Lake People RS05, equipped with a Femto clock oscillator. The sonic improvement from 24-bit 96khz to 192khz is very notable. You only have to listen to a good track for 10 seconds and most people would noticed the improvement. 

I deploy 7x Wyreforsound Remedy reclockers in all digital paths as well, to ensure the clock is reclocked to Femto grade accuracy. 

I love the sounding of the 322. It is very similar to the 321, with the added support for DSD. 

I helped my friend set up a very similar 2-way fully active digital crossover setup, that is based on twin Wadia 122 (since 121 are extremely hard to source). The active digital crossover is done by Nanodigi instead, with 7x Wyreforsound Remedy Femto reclocker deployed in each stage of the digital transmission, driving a pair of JBL 708i, with Goldmund JOB4 based high frequency amps and low frequency monoblocks based on Icepower 500w. His system sounds jaw-droppingly good. Although we started small and overall very budget friendly, the end result was mind blowing and certainly puts many systems costs over 10x more in shame. It's definitely still has much potentials to explore as we upgrade the ultra high frequency to incorporate a pair of Pioneer TAD PT-R7iii. 

The closest pure DAC from Wadia you can currently get that utilises DigiMaster is the Wadia 121. But it is extremely hard to source in good condition. 

I managed to source 3x of these Wadia 121 in my other setup and they do sound very nice. You can read up on various 121 reviews. 

In my second setup i run 3x Wadia 121 DAC's in a 3-way Active digital crossover setup, driving a JBL M2 setup augmented with Pioneer PT-R7iii. Crossover is based on Nanodigi. 

 

Now, by having a solution to harness the greatness of the Exogal Comet, i believe we have open up a great opportunity window for many audiophiles that would like to try the Comet, but concerned about the lack of technical support on the phone app. 

 

Let me know if you need any further information to develop the serial port communication solution. 

I have included some screen captures on the solution that i have quickly put together. You can get C# sample programs in serial communications and augment that easily to suit the Exogal Comet. 

In the version i am using, i captured an image of the Exogal Comet remote control, run it through AI image processing and applied fractal geometry to upscale, enabling me to obtain good resolution to get images on each button to compile a nice graphical user interface that resembles the actual remote control itself. 

The biggest advantage with this solution over the wireless is, i have incorporated display to show the state of each function, including the current state of the volume, on/off, input, output and mute. In addition, left click would increment the volume by 1 step, and right click will rapidly increase this by 50.

So from 0 to 200, you only need 4x right click on the volume button. 😬👍

Exogal Comet Remote control App via serial interface
Caption


 

@damianhl

Wadia 321 is an excellent DAC. With twin 321, are you running 2-way active digital crossover set up?

No, but it sounds interesting and would love to try it if there is not to much investment. How do you build the crossover?

 

interestingly there is a Wadia 121 on ebay for $500

There are 2 mainstream methods of implementing digital active crossover. 

The most comprehensive method is the DEQX. This is also the most popular method. 

It offers automatic software driven calibration for both the speaker and listening environment. And will time align the drivers as well. Very sophisticated. And supports very steep - 300db/oct crossover, depending on the filter chosen.  But has a higher acquisition cost.

The second method is via MiniDSP nanodigi 2x8.

Not many people know about this method, but this nanodigi is highly capable and would also sound incredibly if setup correctly. 

You would also need the plugin software to work :

Unfortunately miniDSP officially stopped making nanodigi last year. But you can still source these easily from other suppliers at a reasonable cost. 

Supports up to 24bit 96khz PCM and up to - 48dB/oct crossover.

The most attractive aspect is the very friendly entry cost. 

It's less than 10% cost compare to DEQX.

It does not offer automatic calibration, time alignment of drivers nor room correction. All setup are done manually via the pkugin software. But if you know what you are doing, it is a straightforward way of setting up active digital crossover quickly in 15 minutes. 

https://youtu.be/CFhD8G0-qS4

https://www.audiophonics.fr/en/dsp-processor/minidsp-nanodigi-2x8-b-audio-processor-28-56bit-2-to-8-channels-p-8451.html