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Other Stuff => Archived Circles => Industry/Sponsored Threads => Topic started by: AirDAC on 21 Nov 2010, 09:03 pm

Title: USB DAC with wireless input
Post by: AirDAC on 21 Nov 2010, 09:03 pm
Hi, I am new on the forum.

I would like to poll if you are interested in a USB DAC with wireless input.

The wireless DAC system compromises 2 units:

1. Transmitter
- USB input
- 24/96 support
- volume control
- headphone output
- wireless output
- battery powered (+/- 50 hours runtime / 500+ times rechargable)
- small 'tabletop' footprint (16 cm x 12 cm x 6 cm)

2. Receiver/DAC
- wireless input
- quality DAC (24 bit resistor ladder)
- fixed and variable outputs
- linear AC power supply
- small 'tabletop' footprint (16 cm x 12 cm x 8 cm)

The wireless technology promises the following:
- guaranteed free from RF interference
- plug & play, no network settings etc.
- 24/96 support
- SNR > 120dB
- true channel separation, 0dB crosstalk
- no latency (< 0.2ms)
- reach about 35 feet (indoor, single room)

Functionality
The wireless DAC system is useful for you, if you want to use a Laptop (or other USB audio device) as source component for your music library and control it at your listening position.

I think this might be an interesting product for (computer) audiophiles and checking out if I am right or wrong.

Your suggestions and/or comments are truly appreciated.

Cheers!
Arend
 
System layout:
(http://img707.imageshack.us/img707/4486/airdacconcept.png)
Title: Re: USB DAC with wireless input
Post by: jtwrace on 23 Nov 2010, 01:15 pm
Welcome to A.C.!!!

I voted "yes". 

Is this something that is in early design stages or close to production?  What else can you say about it?
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 01:26 pm
Hi jtwrace,

We do have a functional prototype, the poll is to find out if there would be a reasonable demand for this solution/product. And if this is the case, does the feature set fulfill most requirements, thus any comment/suggestion is appreciated.
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 01:36 pm
What else can you say about it?

We are also considering to offer a, software based (running on your laptop), digital room correction system with it.
Title: Re: USB DAC with wireless input
Post by: jtwrace on 23 Nov 2010, 02:40 pm
Hi jtwrace,

We do have a functional prototype, the poll is to find out if there would be a reasonable demand for this solution/product. And if this is the case, does the feature set fulfill most requirements, thus any comment/suggestion is appreciated.

What chip will you be using?  Async? 
Title: Re: USB DAC with wireless input
Post by: bpape on 23 Nov 2010, 02:50 pm
Volume control type? 

Any chance of a D/D version so that other DAC's could be used if desired?

Bryan
Title: Re: USB DAC with wireless input
Post by: jtwrace on 23 Nov 2010, 03:17 pm
Volume control type? 

Any chance of a D/D version so that other DAC's could be used if desired?

Bryan

Great idea! 
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 03:21 pm
What chip will you be using?  Async?

At the moment a Tenor IC, not async, btw I am not the electronics designer but the initiator. I am aware that async is 'hot' at the moment but as I have learned there are different ways to eliminate jitter as far as possible.
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 03:27 pm
Volume control type? 

Any chance of a D/D version so that other DAC's could be used if desired?

Bryan

Hi Bryan, yes we are considering to offer digital outputs on the version with DAC (thus the one described above).

We are also thinking of offering a 'wireless link only' version, thus without DAC but only with digital outputs like toslink, coax, aes/ebu and perhaps i2s.

The latter could be interesting for those who already have a good DAC with remote controlled volume.
Title: Re: USB DAC with wireless input
Post by: jtwrace on 23 Nov 2010, 03:30 pm
We are also thinking of offering a 'wireless link only' version, thus without DAC but only with digital outputs like toslink, coax, aes/ebu and perhaps i2s.

I think this would be a HUGE item...
Title: Re: USB DAC with wireless input
Post by: bpape on 23 Nov 2010, 03:42 pm
Agreed.  For something like a laptop or even an SB Touch, that would be something that would be interesting and avoid having to stretch wires across a room (which normally doesn't have high WAF)  :scratch:

You mentioned 'no latency' but I think (could be alone on this) that there would be some sort of buffering in the receiving unit.

Bryan
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 03:49 pm
Agreed.  For something like a laptop or even an SB Touch, that would be something that would be interesting and avoid having to stretch wires across a room (which normally doesn't have high WAF)  :scratch:

You mentioned 'no latency' but I think (could be alone on this) that there would be some sort of buffering in the receiving unit.

Bryan

We also thought about a dedicated SB Touch transmitter, compromising SPDIF input and regulated 5V, battery powered DC output on the transmitter side. In this case you can use the SB touchscreen at you listening position. I think this might be an interesting offer as well but we probably start with the USB version as this market is larger.

Latency is less than 0.2ms which is extremely low compared to RF solutions (typically between 7ms and > 30ms)
Title: Re: USB DAC with wireless input
Post by: chadh on 23 Nov 2010, 03:58 pm

Welcome to AC, and thanks for the interesting post.

I'll apologize right up front for not being unequivocally enthusiastic about the product - but maybe some answers to my questions will help prove what a boon the Air DAC could be.

First - we know that "wireless" devices already exist.  Something like the slim devices/logitech offerings can operate wirelessly, and do so with a couple of advantages over your product.  By taking a wireless signal from the computer directly, they don't need to deal with the extra transmitter component, nor to deal with USB conversion prior to transmitting the data.  It seems that this new product complicates the transmission process more than solutions that already exist.

Despite all of this, almost all the people I know who use this kind of solution actually choose to use it via a wired ethernet connection.  This seems to be because the wireless receiver inside the device adds some noise to the system. 

What does all of this mean?  Audiophiles around here seem to have shown that the wired/wireless issue is of far less importance to them than sound quality.  Especially as you can control PCs remotely with handheld devices or laptops or whatever, separating the PC controlling the music from the system seems to be becoming a less and less vital issue.  The thing that will make or break your product in the audiophile market (well, at least the Audio Circle market) is its ability to deliver superior sound quality.  So, I think it would be best to address the question of why your transmission system:

PC -> USB connection -> transmitter -> some kind of wireless transmission -> Air DAC

would produce better audio quality than

PC -> USB connection -> typical USB DAC

or

PC -> USB connection -> USB-SPDIF converter -> typical SPDIF DAC

or

PC -> WI-FI transmission -> squeezebox

or

PC -> ethernet connection -> squeezebox

Many thanks.

Chad
Title: Re: USB DAC with wireless input
Post by: wilsynet on 23 Nov 2010, 04:02 pm
Why wouldn't I just use a Squeezebox?
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 04:56 pm
Welcome to AC, and thanks for the interesting post.

Thank you Chad.

Quote
I'll apologize right up front for not being unequivocally enthusiastic about the product - but maybe some answers to my questions will help prove what a boon the Air DAC could be.

No problem, this is the reason I started the topic.

Quote
First - we know that "wireless" devices already exist.  Something like the slim devices/logitech offerings can operate wirelessly, and do so with a couple of advantages over your product.  By taking a wireless signal from the computer directly, they don't need to deal with the extra transmitter component, nor to deal with USB conversion prior to transmitting the data.  It seems that this new product complicates the transmission process more than solutions that already exist.

Some prefer to use a laptop as source because of more flexibility (interface/software/usability), with AirDAC they don't need to run a long USB cable. As far as I know the transmission is not more complicated in case of USB audio, conversion is only at a different point in the chain. The USB signal is converted to i2s before being wirelessly transmitted and feeded without conversion to the DAC (USB -> I2S -> DAC).

Quote
Despite all of this, almost all the people I know who use this kind of solution actually choose to use it via a wired ethernet connection.  This seems to be because the wireless receiver inside the device adds some noise to the system.

That is because of RF technology, 'our' technology differs from RF and has a potential 140dB SNR and discrete channels. Unfortunately I can not go into details because I want to respect the NDA with the technology provider. But it's a serious alternative for a wired connection and offers zero noise.

Quote
What does all of this mean?  Audiophiles around here seem to have shown that the wired/wireless issue is of far less importance to them than sound quality.

WAF and convenience are important to some degree otherwise PC based audio solutions like music streamers and servers would not be on the market. The AirDAC solution does not compromise on SQ and serves both WAF and convenience arguments.

Quote
Especially as you can control PCs remotely with handheld devices or laptops or whatever, separating the PC controlling the music from the system seems to be becoming a less and less vital issue.

I agree but using the native interface on your listening position is, in my opinion, more convenient than a smartphone like device.

Quote
The thing that will make or break your product in the audiophile market (well, at least the Audio Circle market) is its ability to deliver superior sound quality.  So, I think it would be best to address the question of why your transmission system:

PC -> USB connection -> transmitter -> some kind of wireless transmission -> Air DAC

would produce better audio quality than

PC -> USB connection -> typical USB DAC

That will depend on the USB DAC

Quote
or

PC -> USB connection -> USB-SPDIF converter -> typical SPDIF DAC

Same here

Quote
or

PC -> WI-FI transmission -> squeezebox

Both our transmission and DAC are better than that of the squeezebox.

Quote
or

PC -> ethernet connection -> squeezebox

Our DAC is better. Regarding the connection, there will be no difference in SQ comparative to the ethernet connection. Ethernet supports bit/sample rates larger than 24/96 but the squeezebox does not.

Quote
Many thanks.

Chad

Thank you for your serious comments, appreciated.
Title: Re: USB DAC with wireless input
Post by: jtwrace on 23 Nov 2010, 05:25 pm
AirDac

I really look forward to hearing more about the products.   :thumb:

I'll take one!   :)
Title: Re: USB DAC with wireless input
Post by: bpape on 23 Nov 2010, 05:42 pm
Chad.

The biggest bennie for me in the touch type version would be not having to wire from the Touch to the system.

Right now, yes, the Touch will connect wirelessly to the server - but not to your audio system.  I would still need to run approx 25' SPDIF or analog interconnects from my seating to my preamp.  With this solution, I no longer have to do that.  All I need is power. Wireless from server to Touch, wireless from Touch to preamp or DAC which is across the room from the Touch.

Bryan
Title: Re: USB DAC with wireless input
Post by: bfr1992t on 23 Nov 2010, 08:01 pm
I'm interested in hearing more. Remote volume control would be killer, esp if it's RF and not in the 2.4GHz band. :) Add an analog input or two, switchable by the same remote. Keep the wireless between the transmitter and receiver stations off of 2.4GHz too if you can.
Title: Re: USB DAC with wireless input
Post by: Goosepond on 23 Nov 2010, 08:40 pm
I've been trying to set up a PC audio system but can't take the first step because I don't want to go down all the false, expensive paths only to realize how to do it better. But you're description of a laptop with wireless connections to a DAC at my system is what I'm looking for, w/o the complications (for me) of a network (one step at a time  :thumb: ).

So count me interested.

And what is the next step as far as announcing/producing your product?

Thanks,

Gene
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 08:45 pm
I'm interested in hearing more. Remote volume control would be killer, esp if it's RF and not in the 2.4GHz band. :) Add an analog input or two, switchable by the same remote. Keep the wireless between the transmitter and receiver stations off of 2.4GHz too if you can.

Thank you for your response however I am not sure if you understood the concept correctly. RF is not used for wireless transmission hence it's guaranteed free from RF interference.

Do you mean to put analog input(s) on the receiver or transmitter side of the system? I can not see the added value of analog inputs so please explain why this could be useful.

(http://img707.imageshack.us/img707/4486/airdacconcept.png)
Title: Re: USB DAC with wireless input
Post by: AirDAC on 23 Nov 2010, 08:57 pm
I've been trying to set up a PC audio system but can't take the first step because I don't want to go down all the false, expensive paths only to realize how to do it better. But you're description of a laptop with wireless connections to a DAC at my system is what I'm looking for, w/o the complications (for me) of a network (one step at a time  :thumb: ).

So count me interested.

And what is the next step as far as announcing/producing your product?

Thanks,

Gene

Hi Gene, nice to hear that the solution is attractive for you. One of the advantages of our system is indeed that it is plug & play, no network settings needed.

The next step is that we will review all opinions on this forum and adjust our prototype there where needed. After that (summarized) we will take the product to production level, to proceed with a first production batch.
Title: Re: USB DAC with wireless input
Post by: jtwrace on 23 Nov 2010, 11:59 pm

The next step is that we will review all opinions on this forum and adjust our prototype there where needed. After that (summarized) we will take the product to production level, to proceed with a first production batch.

I hope I can be part of the beta program.   :green:  I think I've got a pretty good USB Dac I can compare it to...and test the wireless part.   :thumb:
Title: Re: USB DAC with wireless input
Post by: AirDAC on 24 Nov 2010, 04:37 pm
@jtwrace

I will notify you when we are in that stage, thank you.
Title: Re: USB DAC with wireless input
Post by: AirDAC on 1 Dec 2010, 09:15 pm
I think this would be a HUGE item...

Hi jtwrace and other interested AC members,

We have been calculating and a 'wireless link only' version would retail for about 500 USD (freight, taxes and duties not included).

Summarized you get this for 500 USD:

A wireless USB connection for use between Laptop/USB audio source and DAC, compromising:

- 1 x wireless USB transmitter, battery powered (run time 50+ hours, 1.500+ times rechargable LifePO4).
- 1 x wireless receiver with toslink, coax and aes/ebu digital outputs and perhaps i2s.
- 24/96 support
- guaranteed free from RF interference
- reach about 35ft, indoor single room
- < 0.2ms latency
- 0dB crosstalk, discrete L + R channels
- small 'tabletop' footprint (16 cm x 12 cm x 6 cm)
- quality finished enclosure but no overkill
- Plug & Play

My question for you, would you still be interested considering the price?


Title: Re: USB DAC with wireless input
Post by: jtwrace on 1 Dec 2010, 11:14 pm
AirDac

 :scratch:

In my opinion, $500 without shipping is a bit steep.  Not that the development and product isn't worth it I just think it's a bit much. 

Of course, it has to sound the same as being plugged in for one of us crazy audiophiles. 

Also, I don't see a USB receiver option.  USB transmitter but then the USB dac plugs into???
Title: Re: USB DAC with wireless input
Post by: AirDAC on 1 Dec 2010, 11:27 pm
@ jtwrace

I understand it's quite pricey, this is because it is a 2 box solution, casework is expensive and battery on Tx side also adds to the build price considerably. What do you mean by USB receiver? The 'wireless link only' system will have a USB input on the transmitter side, the receiver side has only digital outputs so that the user can use his own DAC.

Thank you for your response.
Title: Re: USB DAC with wireless input
Post by: jtwrace on 1 Dec 2010, 11:32 pm
What do you mean by USB receiver? The 'wireless link only' system will have a USB input on the transmitter side, the receiver side has only digital outputs so that the user can use his own DAC.

Lets say my Mac Mini is in a different room than my USB DAC.  I would plug the trasmitter into the Mac Mini USB port.  Then the receiver can plug into the USB dac.  No?
Title: Re: USB DAC with wireless input
Post by: AirDAC on 1 Dec 2010, 11:38 pm
Lets say my Mac Mini is in a different room than my USB DAC.  I would plug the trasmitter into the Mac Mini USB port.  Then the receiver can plug into the USB dac.  No?

No, unfortunately this will not work as the wireless link only works in a single room. The receiver can only be plugged into your USB DAC if it also has a toslink, coax or aes/ebu input, there is no USB output on the receiver side.
Title: Re: USB DAC with wireless input
Post by: jtwrace on 2 Dec 2010, 08:38 pm
No, unfortunately this will not work as the wireless link only works in a single room. The receiver can only be plugged into your USB DAC if it also has a toslink, coax or aes/ebu input, there is no USB output on the receiver side.

After thinking about this, I would pay the $500 for the piece if I could do what I want.  This would allow my Mac Mini and HD's to be located in the office where my router (Airport Extreme) is in and also have a nice NAS system. 

Another benefit to me would be when I want to go through and organize my music library I wouldn't have to camp out on the floor in front of the stereo. 

If it was wireless with no sonic degradation, I'd do it.