AQVOX USB power supply problems

[Richard Dale]

I ordered an AQVOX USB power supply about a month ago from PlayStereo in Italy. It was shipped by TNT and it turned out to be a nightmare. The unit was returned from Madrid to Milan three times by the Spanish customs. When it finally arrived today I was presented with a bill for 63 euros in 'tax', when the actual unit only cost 96 euros plus 20 euros shipping. In theory the sales tax in Gran Canaria is 5%, but in practice it seems I'm paying more like 65% and being subject to arbitrary delays.

 

It is a small unit with a linear power supply. You plug one end into the mains with an IEC mains cable. The other end has a thin 5 volt cable to supply the USB device - it is terminated with an adaptor that you plug into the B type socket of your USB device. You then plug your standard USB cable into the adaptor.

 

I set the device up, and it doesn't work - my Macintosh never sees a USB device has been plugged in, although my DAC works fine if plugged in directly. If I had installed it and found it sounded great, all the hassle with the shipping delay and cost wouldn't have been so bad.

 

I left my HRT Streamer II+ for a bit plugged into the power supply, and it ended up getting warm. So that must mean the 5 volts via the power lines is getting through OK.

 

I wonder if the unit isn't faulty, but I have a problem with my Macintosh not recognizing devices which aren't powered for some reason. Or another possiblility is that the unit is faulty, and the data connections from the USB cable through the adaptor to the DAC are broken. Does anyone have any ideas about what might be wrong, or how I can investigate further?

 

[elcorso]

Richard what is your country voltage?

 

I order mine from AQVOX in Germany, and they send me an 220 -> 110 volts adapter (had to pay an extra for the adapter). Since America voltage is 110-120 ACV.

 

Roch

 

[Richard Dale]

 

elcorso: "Richard what is your country voltage"

 

 

 

I'm in Spain and so that is 220-240 volts. On the power supply it says 'Input 230V ~ 50 Hz 80 mA' which should be fine for me.

 

 

[Richard Dale]

I've just tried plugging in the AQVOX to my La Cie Quadra via the adaptor. The Quadra has its own power supply, and wouldn't need any power from the AQVOX. It worked fine and mounted on Linux, and I could see the data on the disk OK.

 

So I get the feeling that the power supply isn't faulty, but it seems incompatible with my HRT Streamer II+ in some way (it didn't work with my V-Link either). On the AQVOX web site they did specifically indicate that the PSU was compatible with the HRT though.

 

[Isar12]

Unfortunately I have to report that I experienced the same thing. My M2Tech Young won't mount under OS X 10.6.7 with the Aqvox in place. OTOH, a friend who lent me the Aqvox, uses it with a different DAC and his Mac Mini to good effect. YMMV.

 

[elcorso]

Richard, try to invert the polarity of your AC plug. In my case it's easy since they are two round plug pins (no ground pin).

 

But do this with everything in the OFF position on your audio system.

 

Regards,

 

Roch

 

[sandyk]

Richard

Does it work with a USB stick plugged in ?

I use a more sophisticated DIY version of this device to good effect. It even stopped a friend's USB writer from buzzing when ripping CDs.

 

SandyK

 

[barrows]

I would contact HRT tech support and ask them if their DACs are compatible with this type of external supply-then you will have a definitive answer.

Roch: can you confirm that your Wavelink works with this external supply method? I am interested in experimenting with an external supply on the Wavelink if it is possible.

 

[elcorso]

Barrows, yes it works with the Wavelink, Halide Design Bridge and USB sticks. I got a lot of Hi Freq. noise (like jitter), then I inverted the AC plugg of the AQUVOX, and the noise is gone.

 

I'm not completely convinced if this PSU improved the SQ... since I changed at the same time the USB cable: WireWorld (the red one) to Acoustic Revive USB-1.0SP, wich has to cables, one to supply the power and the other the music signal. This last upgrade was really incredible, since I got much more channel separation, then a wider sounstage without center loss. This cable is expensive in the USA, but I found half the price on another place***. But I can see you have an excellent USB cable, the Nordost.

 

Regards,

 

Roch

 

***If you want to know the link write me by PM, please.

 

[sandyk]

I could be wrong here, but I think this is likely to be a basic DC supply relying mainly on a fairly larger filter capacitor.To extract the most from an external supply you really need a voltage regulator followed by a low noise and low impedance "super regulator" such as the Paul Hynes, Salas,JLH etc. A recent independent test of the JLH is at the attached link.

http://www.diyhifi.org/forums/viewtopic.php?p=44061

A basic DIY kit such as the USB Power Injector seems likely to give similar results to the Aqvox ? It only gives a small improvement in it's published form, although playing around with the 7805 input and output capacitor types and values can further improve performance.

 

http://www.altronics.com.au/index.asp?area=item&id=K2910

 

[barrows]

Agreed. I use Salas regs in my DAC to great effect. I was only wondering if the Wavelink works with an external supply implemented this way. I shall probably test with a 5 VDC supply I already have kicking around (LiFePO4 battery, DEXA low noise regulator, followed by 4x1000uF Cerafines). If this approach does not improve sonics, I doubt an even more sophisticated approach will, but if it does, then I might continue on and build up one of my Salas boards for this. Of course, the internal performance of any component is also going to depend on the local regulators and decoupling.

I would recommend to anyone trying the AQVOX, if this device does improve the performance of your DAC/interface, then consider upgrading to a more tricked out supply to get the most out of it.

 

[Richard Dale]

 

elcorso: "Richard, try to invert the polarity of your AC plug. In my case it's easy since they are two round plug pins (no ground pin)."

 

 

 

I've just tried inverting the polarity and that doesn't make a difference.

 

 

 

Yesterday I emailed AQVOX and they said there was a problem with the USB adaptor. They could either send me a new unit, or just the adaptor if I didn't mind soldering it on myself. So I think I'll ask them to send me a new adaptor, as I might have another shipping nightmare with the Spanish customs if they send the whole unit in a box.

 

 

 

I'm still a bit puzzled as to what can go wrong as I would have thought that either the two data wires are connected or they aren't, and that either the two power wires are connected or they aren't. My test with the HRT indicated the power wires were connected ok, and trying it with a La Cie hard disk indicated that the data wires were connected ok. So there must be more to it than I think there is.

 

 

[sandyk]

I can't presently see why it wouldn't work provided that the 0 volts/earth line from the USB port isn't broken.Only the +5V wire should be opened to insert the external PSU.

 

SandyK

 

[cristofori]

Hello,

 

I did have the same problem with the USB B to B male/female connector.

 

I wanted to use the PSU with an Hiface and an HRT MS II.

 

I contacted AQVOX and the problem is that both devices need a common ground between the computer and the device. (only the +5V connection cut)

 

I think that the USB A to A male/female PSU specially made for Hiface will solve the problem.

 

You have to precise common ground in your order to AQVOX.

 

Regards

 

 

[Richard Dale]

Ah, thanks for the info - I think I understand what is going wrong now. I ordered a new adaptor from AQVOX this morning, which is assume will have the different ground arrangement.

 

[barrows]

Sandy.

 

"I can't presently see why it wouldn't work provided that the 0 volts/earth line from the USB port isn't broken.Only the +5V wire should be opened to insert the external PSU."

 

This is my understanding as well. I am just going to make an adapter via USB B plug/jack for testing, with the external supply referenced to the existing ground, and V+ broken to the computer. This way no mods need to be done to the internals, and I can use my (excellent) Nordost USB cable.

 

 

 

[elcorso]

You need the common ground pass trough, since with the Wavelink (and most the USB interfaces) needs the common ground (Pin 1). That way the device will be recognized by the computer.

 

The only interrupted one is Pin 1 (+ 5V), where the AQVOX feeds the current to the interface.

 

I order it from AQVOX directly in Germany, and in the proforma you choose the USB connector type A or B, and wath it is your final use, in order to ship the right one for you.

 

And Richard, please don't talk about Ship. & import taxes, if you see mines to my country, you will cry for me!

 

Regards,

 

Roch

 

 

 

[Richard Dale]

 

elcorso: "I order it from AQVOX directly in Germany, and in the proforma you choose the USB connector type A or B, and wath it is your final use, in order to ship the right one for you."

 

 

 

I think it is unreasonable for people to understand the difference between devices which need to work with a common ground, and devices which don't when they order a PSU. What AQVOS need to do is to change the 5 volt cable from the PSU so that it has an inline connector. Then they need to provide various types of adaptor that can plug into the inline connector, like USB B/common ground or not common ground, USB mini and so on. Then they need to document when and why you would need the different adaptors.

 

 

[elcorso]

Barrows and gang, after almost 100 hours listening with the AQVOX Low Noise USB PSU feeding the WaveLink I can tell you that it has improved the SQ on my system.

 

Last time I was no fully convinced since I was testing, as I told you, a new USB cable (Acoustic Revive USB-1.0SP). The matching of the two new items are very impressive, at least to my ears.

 

The only care with this PSU is to isolate it from noise from another PSU, and to be careful with the correct position of the AC plug, if there is Hi Frequency noise (similar to high jitter) you have to invert the plug.

 

Best regards,

 

Roch

 

PS/ As Barrows quote "Everything matters"

 

[ted_b]

with the AQVOX, since the AQVOX connects at the DAC end (which is the joined end of the AR cable; the other end being the split power/signal connectors)? What do you use at the power connector end of the AR cable (which is eventually not used and replaced by AQVOX power anyway)?

 

I ask cuz i have a Revelation Audio dual conduit cable coming soon for evaluation, and want to provide clean USB power to see if it cleans up my audio to my Antelope Gold. I'm really not even sure what, if any, power is used from the 5V USB bus, since the Antelope is plugged in and has its own hi-end power supply (Voltikus) etc.

 

Thanks

Ted

 

[elcorso]

Hi Ted,

 

I have a Wavelink interface, Standar B connector of the AR cable goes to the Wavelink. One of the Standar A connector of the AR (the red one), goes to one the USB port of the Mac, but with AQVOX USB adapter in between. You need this since the (-) power sense the Wavelink, the (+) is interrupted at AQVOX USB adapter, where he feeds the power to the Wavelink. The other Standar A connector of the AR goes to another USB input on the Mac: The signal wires (D+ & D-).

 

The only caution you should take is to invert the power plug in the AQVOX, if you find the SQ is not good.

 

Roch

 

[ted_b]

the pictured and likely standard way...the DAC (in your case, Wavelink) end. So I should order A connector if I use dual conduit (AR or Revelation) cable, otherwise B connector, right? Thx

 

[barrows]

I would suspect applying the power supply at the DAC end (in my case Wavelink as well) would be preferred. DC supplies do not like to be run through cables, as this adds inductance, keeping that cabling as short as possible is a benefit.

I use a DIY (LiFePO4 battery, regulated and filtered) with my Wavelink, and made a USB "B" adapter to supply the power right at the input to the Wavelink. Big sonic gain for me.

 

[ted_b]

it makes moot the idea ofthe AR/Revelation dual conduit USB cable design that has separate signal and power cables separated at the source end (only)....except I guess in your example my dual conduit cable would have NO power coursing through it for all of its length?

 

[elcorso]

Ted you can order it as you want, it depends on your needs, in the proforma you should state all this.

 

Roch