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Raimund Heubel

Afi+USB-Module - USB-Interface, Isolator and Re-Clocker

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The Artistic Fidelity Isolator plus USB-Module is probably the most enhanced and thought through USB interface I have yet come across, for sure it is for me the most revealing and sounding of such devices!

This DDC strictly speaking consists of two devices: the external USB-Module (powered by the computer's USB port) and the Afi itself (powered by an external PSU).

My Mac mini is connected via a short USB cable to the external USB-Module, the module is connected via three 2 meter long (!) fibre optical cables (FOCs) to the Afi which outputs the re-clocked digital audio signal via an RJ45-to-AES/EBU adapter cable to my T+A DAC8.

The reason for this set-up is:

a) Isolation from the computer source

The one of the three fibre optical cables carrying the audio stream from the USB-Module towards the Afi has no direct electrical pathway for High Frequency (HF) noise from the computer. The USB-Module and the Afi itself are completely galvanic isolated from the computer.

b) Re-Clocking

The 2nd FOC from the Afi towards the USB-Module contains the new clock signal generated by high precision oscillators in the Afi - completely independant from the computer.

The 3rd FOC from the Afi towards the USB-Module transmits the switching signal for each of the sampling rate family multipliers either 44.1 or 48 kHz based.

The Afi itself outputs the re-clocked audio signal in the RJ45 Ethercon format hence requires an adapter cable to connect to my T+A DAC via AES/EBU port.

The sonic result of this set-up is simply stunning, instruments and voices sound much more natural and organic than ever before in my set-up when having connected the mini via 2 Jitterbugs and 1 Regen Amber to the DAC8' s USB port. Yes, there is much more black and quiet background, instruments and voices can be much better separated and followed during a song. They sound as if I am in a Live performance in my living room!

No artefacts, not the slightest sign of steril digital sound anymore but a much more analog presentation from a digital music source..., what a dream coming true! I am sorry for my emotions and enthusiasm here but I think I have found the ultimate USB interface for my set-up.

It costs €1.220 = $1.365 incl. adapter cable - for sure not cheap - but it is in my opinion worth every €/$.

More detailed information can be obtained from the German Manufacturer's website under http://www.artistic-fidelity.de

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The 3rd FOC from the Afi towards the USB-Module transmits the switching signal for each of the sampling rate family multipliers either 44.1 or 48 kHz based.

Correction to above: the data do obviously flow from the USB-Module to the Afi and not as described above in the other direction as otherwise the Afi would not 'know' which of the two oscillators to use for re-clocking.

Let me also point out one more thing, the reason why I think the Afi + USB-Module is so good is its ability to eliminate the HF noise very efficiently which acc. to his developer Ralf Koschnicke from ACOUSENCE is the reason why USB-audio so far did not sound as good as it could.

I believe the Jitterbugs, Regens, Mutecs and other conventional USB-interfaces or Re-Clockers are all very good at filtering, signal rebuilding, re-clocking and even isolating. Not a single of these devices however eliminate the HF-noise from the computer as consequently and efficiently as the ACOUSENCE Afi + USB-Module does through its two device design and the use of the 3 Optical Fibre Cables between them.

This is the unique design difference beteeen this USB-interface and the competition which in my honest opinion let the Afi + USB-Module shine so bright in sound.

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Aww go on someone. One and a third dollars (that's less than a pound over here!) And obviously it's the best. Even gets rid of HF-noise! Alex....John S...anyone...?

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To my ears the AFI is just as good as Raimund claims. Compared it to the Mutec MC3+ USB. The optocouplers may become a problem in the future, but it is one of the best tools for USB available, it certainly is the best I have tried so far.

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Aww go on someone. One and a third dollars (that's less than a pound over here!) And obviously it's the best. Even gets rid of HF-noise! Alex....John S...anyone...?

I know the Afi + USB-Module is NOT cheap but the sound in my eyes is worth the price. I tried the Regen, the Jitterbugs, all the Mutecs, I could unfortunately never get my hands on a BADA USB test unit - they are not selling in the EU -, they all do not provide the level of analog sound as the Afi + USB-Module does.

You do not need to believe my statements of course, I suggest you have a listen to a test device and convince yourself of this in my opinion break through concept.

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To those who have used the Afi + USB module and also use a Mutec MC-3+, have you found there is a benefit to adding the Mutec MC-3+ or Mutec MC-3+ USB?

 

Thanks,

 

Joel

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To those who have used the Afi + USB module and also use a Mutec MC-3+, have you found there is a benefit to adding the Mutec MC-3+ or Mutec MC-3+ USB?

 

Thanks,

 

Joel

 

Hi Joel,

 

I have a cascade of 2 MC-3+ USB I am very happy with. I had the opportunity to test the Acousence AFIS-USB. There is in my opinion no interest to stack them. The AFIS-USB (AFI-USB is the exact same if you are interested in only one input) does a perfect job alone. As stated at the beginning of this thread, and this is my understanding too, the unique restitution quality of Acousence is linked to the perfect galvanic isolation provided by the optical connections.

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Hi Swissbear,

 

Thanks for the reply. So, just to be clear, not only would you not use two MC-3+ USB's with the AFIS-USB, you wouldn't use one MC-3+ USB with the AFIS-USB either, is that right?

 

Joel

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looks like a new commercial advertising to enter in the niche of USB /spdif isolator / reclocker etc.. :)

the sonore way to get a clean USB data by building it instead of cleaning it seems for me the right solution.

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Hi Swissbear,

 

Thanks for the reply. So, just to be clear, not only would you not use two MC-3+ USB's with the AFIS-USB, you wouldn't use one MC-3+ USB with the AFIS-USB either, is that right?

 

Joel

 

Correct. Just try this piece of HW and you will be stunned IMHO.

 

On top of that, Ralf Koschnicke, the owner of Acousence, is a very nice man, very competent in the field of digital music, who runs his own digitization studio. He personally cares for his customers, which is not the case at Mutec where you do not always get answers to your questions. This service is, in my opinion, a very valuable part of the customer experience :-).

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looks like a new commercial advertising to enter in the niche of USB /spdif isolator / reclocker etc.. :)

the sonore way to get a clean USB data by building it instead of cleaning it seems for me the right solution.

 

The best way to go probably is to avoid USB at all ; but this is not easy to achieve is you want to stick to your Mac. Then apart from the mystery piece of HW everybody is excited about and nobody has ever heard (µR), the only sensible way, for someone who believes what he/she sees/hears, is to go with Mutec or AFI-USB. Mutec is nice but AFI-USB is better IMHO.

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you are wright but we can't by all of them just to compare. i'm not searching the better stuff on earth

(it changes every month ) , just the simpler way to get decent sound from the crappy computer audio.

i'm sure the Afis like the muted help but i'm not sure it will dispense to " tweak" the computer side ( hardware , power supply ,etc..) like the sonore stuff will probably do. ( in theory for the moment )..

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i'm sure the Afis like the muted help but i'm not sure it will dispense to " tweak" the computer side ( hardware , power supply ,etc..) like the sonore stuff will probably do. ( in theory for the moment )..

 

Hi Juanitox,

 

After testing for myself, I can assure you that it does actually dispense to tweak the computer side. My MacMini is off the shelf, and it did a splendid job. Removing the HF perturbation is exactly what this device has been designed for. And it allows, IMHO, a greater flexibility in terms of choosing the player, for a price which, if you compare apple to apple (deduct the European VAT on one side, add a good LPSU on the other), is very similar.

 

Enjoy the µR when it is available :-)

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Enjoy the µR when it is available :-)

 

if it comes out one day , i also don't see any information for ordering on the acousense website too..

these days the reputation of a product came before the selling and not the inverse :)

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You may approach Mr. Koschnicke by E-Mail, please see the contact details on the Artistic Fidelity (ACOUSENCE) website. Also a lot of background info is mentioned there with respect to the Afi(s) design concept incl. the choice of the RJ45 Ethercon output format. The later unfortunately only available in German language in chapter 'Options'. The RJ45 Ethercon output is unusal in the world of HiFi products but a quite interesting format contributing to the elimination of the HF-noise from the computer.

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I was recently made aware of a customer to this thread. After looking across the posts, a few comments:

One day the optocouplers gain will go apesh$t and will start trashing the signals. Six of them to be fixed.

Another method, please?

In my opinion this apprehension lacks any real basis. Afi+USB does not use optocouplers. It uses professional fiber optic transmitters. When operated within specifications regarding temperature and current – and that's the case – the LEDs in the transmitters will work as long as LEDs normally work and that is almost eternal. In my whole life I have never seen a broken LED. I go so far as to give a lifetime replacement warranty for the fiber optic transmitters. So sure am I that this will never happen.

Moreover, even if the transmitters are very old, the LEDs do not just broken. You only lose intensity. Since the transmitters are however designed for 70 meters and we use only 2 or 6 meters, the margin is huge, before no signal arrives. In addition, the signal quality on the fiber optic line is completely irrelevant to the sound quality, if only just good enough to properly differentiate between 0 and 1.

looks like a new commercial advertising to enter in the niche of USB /spdif isolator / reclocker etc.. :)

the sonore way to get a clean USB data by building it instead of cleaning it seems for me the right solution.

The really exceptional of the Afi+USB design is I think not yet clear. Here no USB is cleaned. Afi+USB works as a real source device, together with a computer that delivers the audio data. Inside of the Afi there are two reference oscillators which are clocking the audio data stream under ideal conditions and, because of the fiber optical connection to the USB interface, isolated from any influence by the computer as good as possible. The small external USB interface quasi only provides the data to the Afi. All things important for sound are done in Afi.

As far as I can see, Sonore makes in this respect nothing else like many others. This basically seems to be the same concept as in the MC3+USB. In my view the main drawback is there that the USB receiver is sitting on the same board in the same case. Also in my experience the usual electronic components for galvanic isolation do not shield RF interference good enough.

RF has the nasty habit, not to stick to physically existing conductors. Therefore I felt the design concept of Afi+USB – two spatially separated devices and fiber optics – is important for very clean islolation of all computer technology from the audio processing.

 

More info on our website: afi(s) - USB module

But I am sorry, not all sites are available in English language at the moment and photographs will only be added during next week. Requests by email to me (koschnicke@acousence.de) are very welcome.

 

Best wishes

Ralf

 

ACOUSENCE

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Hi Ralf,

 

I look forward to more information about the afi(s). And have a question for you.

Could the external USB-FOC also (or instead) have a ethernet connection. I thing you could avoid the direct presence and connection of the computer by enabling a ethernet connection.

 

What from your products are appropriate to use with a DAC with no USB input, by SPDIF or XLR?

 

Finally, on the page afi(s) - USB module

when you describe connections 2 and 3, the main reason for this decoupling was it to allow reducing RF or something else?

 

I am a believer on fiber connections and look forward to be able to test this one day.

 

Thanks.

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Thank you Mr. Koschnicke for the reply.

 

I don't understand how a light to an electrical interface can be anything other than an optocoupler even if it has an RF connection or similar, but will accept a lifetime warranty for the FO connections of the afi system.

 

While I have your ear, could there be more detail on your website to assess the afi.

 

Understand the photos are coming next week, will be keen to view them.

With there being no photos of the equipment, just a shadow outline and a schematic of how components are connected, makes a decision to even consider the afi a difficult proposition.

 

Specifications ? Where are?

 

What are the optical connectors, the cabling type needs to be known in advance, might even have the correct ones in use.

 

A simple photo would provide this information, or a link to manual in German or English, preferably both.

 

A photo would asses the quality of the build of the case, after all this equipment will be in people's lounge rooms, not necessarily in a studio/workshop.

 

As far as RF is concerned, a low pass filter works very well, since the energy from RF sources with compliance to Class B EMC at least is well known and controllable. The lower order frequencies from 100kHz are harder to work with, since they are close to being coupled to the DAC. Generally, depends also, on the level/implementation of galvanic isolation to divorce the source to the load of course.

 

The highest criticism though ends up at the RJ45 output for a DAC connection. Even in the pro circles, AES3 XLR or a cinch jack are still in existence, is the afi isolator that small as to only provide an RJ45? There's then another cable to buy, and the collection of favourite XLR cables is not used. Is the RJ45 connector the shielded type? what are the pinouts?

Far as I know, there's RJ45 to XLR adapters, like a snake, but why bother with these, when the standard XLRF will work fine? Many audiophiles would not welcome the RJ45.

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A simple photo would provide this information, or a link to manual in German or English, preferably both.

Hi One and a Half,

 

Here you are (probably still a prototype at this stage, but gives an idea of the construction) : aktives-hoeren.de • Thema anzeigen - Acousence afi(s) und afi(s) USB

 

I will leave up to Ralf to answer on the connections. Just a precision : the RJ-45 Ralf uses is just a way of transporting signal with lower interference and echo on the cable itself compared to AES/EBU cable. It just needs a small adapter at the end of the cable to get the appropriate connection to AES/EBU or BNC. Price for the adapter is minimal (25 EUR if not mistaken). You can also order the output cable with the appropriate connection ; it will be shipped with an RJ-45 connection to the device and an AES-EBU connection to your DAC.

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Hi One and a Half,

 

Here you are (probably still a prototype at this stage, but gives an idea of the construction) : aktives-hoeren.de • Thema anzeigen - Acousence afi(s) und afi(s) USB

 

I will leave up to Ralf to answer on the connections. Just a precision : the RJ-45 Ralf uses is just a way of transporting signal with lower interference and echo on the cable itself compared to AES/EBU cable. It just needs a small adapter at the end of the cable to get the appropriate connection to AES/EBU or BNC. Price for the adapter is minimal (25 EUR if not mistaken). You can also order the output cable with the appropriate connection ; it will be shipped with an RJ-45 connection to the device and an AES-EBU connection to your DAC.

 

Thanks Swissbear for the link on the photo. If I'm not mistaken there doesn't seem to be a LED for DSD, PCM rates exclusively are represented. Now that's a show stopper right there.

 

Echo on an AES cable : Not heard of this concept, the echo would have to be symmetrical to pass the balanced connection, I don't think echo could be that good, perhaps reflection is that the term? 100m ...yes, but not 0.2m something. Would need to see a graph/scope pictures to be convinced.

 

The FO connector is not an STP, these are everywhere, various lengths with bandwidth to the stratosphere. Far too proprietary and closed shop.

 

The separate PSU is a good idea, it has a Switching AC-DC, from there a linear supply?

 

Tapping fingers on the desk here. Let's wait and see.

 

Do you still have the Afi isolator?

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One and a half, I'm getting the impression that you're dissecting the specifications of this brand new product on micro level to early? With true respect for you enthusiasm and interest, wouldn't it make more sense to focus on the musical joy first?

 

I hope you keep in mind that Acousense isn't a big brand company with ditto marketing department en product launch preparations, luckily it isn't :-) Also hope you appreciate the already extensive information on the website (given the solder inside is still hot), the German forum, as well as the personal involvement of Ralf.

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One and a half, I'm getting the impression that you're dissecting the specifications of this brand new product on micro level to early? With true respect for you enthusiasm and interest, wouldn't it make more sense to focus on the musical joy first?

 

I hope you keep in mind that Acousense isn't a big brand company with ditto marketing department en product launch preparations, luckily it isn't :-) Also hope you appreciate the already extensive information on the website (given the solder inside is still hot), the German forum, as well as the personal involvement of Ralf.

 

musical joy like real or fake review are subjective , and they are tons of new company claiming they'v got the new best thing of the moment. so the more informations we can get on the hardware and technics is what we need first before delirious review and warning groupies .

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One and a half, I'm getting the impression that you're dissecting the specifications of this brand new product on micro level to early? With true respect for you enthusiasm and interest, wouldn't it make more sense to focus on the musical joy first?

 

I hope you keep in mind that Acousense isn't a big brand company with ditto marketing department en product launch preparations, luckily it isn't :-) Also hope you appreciate the already extensive information on the website (given the solder inside is still hot), the German forum, as well as the personal involvement of Ralf.

 

Totally agree with you. And even more so since the absence of DSD support is a show stopper :-)

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It's a show-stopper only for those for whom it is a show-stopper. For some of us it is not.

 

And for all the audiophile philosophers out there, enthusiasm AND cynicism are unwarranted until you've heard it.

 

Joel

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