[wilsynet]

There's been quite a bit of buzz recently regarding the M2Tech Hiface USB to SPDIF converter.

http://www.m2tech.biz/products.html

As I understand, some modifications can be done to the device to make the power supply external.

Any thought about modifying units for people and selling them the external 5V power supply?

[Paul Hynes]

Hi wilsynet,

I am preparing a supply for this purpose at the moment. A USB cable connects the computer to the power supply. The power supply passes the digital signals and replaces the USB supply with my high performance shunt regulator.

Regards
Paul

[wilsynet]

A very creative and nice solution indeed.

Could you share availability and pricing information?

[ferenc_k]

I can be interested too 

However hope to get this soon for some experiment:



A special USB hub for laboratory measurement purposes, 1A for each port.
They say:

- Ultra low noise for optimal performance of audio and video recording equipment
- Durable cast aluminum housing suitable for the most rugged environments
- Oversized power source guaranteed to support current intensive USB peripherals on all 4 ports simultaneously

Some more info from lan Olsen (Chief Technology Officer of Vaunix Technology Corporation) about the  LabBrick USB hub power supply and isolation.

"...We cannot say that the LPH-204B is an isolated hub product, nor can we say that its ground connection is truly isolated from the host PC. This would be a misrepresentation of the facts. We can say that the +5V (VBUS) and the data lines (D+ and D-) are isolated from the host PC. We may also say that the hub is reactively decoupled from the host PC. Alternatively, we can say that the hub (including ground) is well filtered. The question ... regarding the isolated ground stems from the user's concern that ground loops and ground noise can effect the performance of his USB peripherals. This is a valid concern. Here is some more background information on isolated USB hubs. There are some isolated USB hubs available on the market. Their data transmission speed is limited to 12 Mbps (full-speed). This is because the isolation circuitry restricts transmission bandwidth and introduces significant propagation delay. This precludes operation at high speed (480 Mbps) and renders the hub useless for many applications, including video. There are no USB hubs on the market that have just the ground connection isolated. To isolate the ground connection without isolating the data lines puts the equipment at great risk to damage. A very slight ESD or transient event (power-up or power-down) can cause this damage when the ground is floating....

... The LPH-204B uses a switch mode power supply.

From a customer's perspective, this may be a bad thing as they may be concerned about switching noise. Switching noise should not be a concern. We use a proprietary design that yields a very clean output voltage. This design was originally developed for our signal generator product line. These signal generators have a specification that requires the spurious energy to be below -80 dBc! ..."

Sorry Paul to derail of your toipic 

[JDUBS]

Paul

Another interested party, here.  I think this product has a lot of potential, applicable to more than just the M2Tech Hiface, but also to the many other USB DACs / converters out there that are USB-powered.

-Jim

[Paul Hynes]

Hi wilsynet,

My standard SR1 and SR3 power supplies can be ordered with USB connectors on the back panel. Signal is passed through and the SR1 or SR3 power supplies provide the power for the USB peripheral. The SR1USB-05 costs £190 and the SR3USB-05 costs £280. Current lead-time on orders is around 30 working days.

Hi Ferenc,

You have not derailed the topic. The LabBrick USB hub looks interesting at first glance, but how good it is, when used for digital audio power, remains to be seen. One thing it does not have is my regulator circuitry.

Hi JIM,

Either power supply will provide enough current to power several USB peripherals by adding a bus powered USB hub between the power supply and the peripherals. The Hub should think the power supply is the computer power feed and continue as normal.

Regards
Paul

[ferenc_k]

Hi Paul,

probably your PS can be used to power a hub like this ? 

[Paul Hynes]

Hi Ferenc,

The SR3-12 will provide up to 3 amps continuous, 10 amps transient so it should make a good upgrade for the LPH-204B 12 volt wall adaptor.  The LPH-204B internal 5 volt regulators would still be part of the overall sonic result.

Regards
Paul

[JDUBS]

Hi wilsynet,

My standard SR1 and SR3 power supplies can be ordered with USB connectors on the back panel. Signal is passed through and the SR1 or SR3 power supplies provide the power for the USB peripheral. The SR1USB-05 costs £190 and the SR3USB-05 costs £280. Current lead-time on orders is around 30 working days.

Paul, how is the M2Tech Hiface design you're working on different than the SR1 or SR3 with USB connector on the back?

Thanks,
Jim

[wilsynet]

I don't think there's any difference.  Unfortunately, Paul used the words "I am preparing" which I think to most of us means he's in the development phase.  What I believe he really meant is "I am currently building just such a power supply for a customer right now and you can order one too!"

I have just ordered one from Paul and I have even paid him using PayPal (which he accepts as a form of payment but is not listed on the web site).

[Paul Hynes]

Hi Jim,

The power supplies are the same. There is a dual socket USB 2 connector module in place of the normal power output socket. The input USB socket is type B and the output USB socket is Type A.

Hi wilsynet,

You are correct in this case although I will try to be a little more specific in future as ‘in preparation’ could also mean a ground up design, production engineering or a small modification. The external patch-in trial worked fine. To keep things tidy and consistent I designed a small module to accommodate the USB 2 sockets. The printed circuit boards for this module will take around 3 weeks to arrive from my board manufacturer.

Regards
Paul