New power supply for Logitech Duet

[VT67]

Hi guys

Is there somebody out here who had a chance to take a look at the insides of the VDC 9.0 from CIAudio? As I'm looking for a new power supply for my Logitech Duet I am curious if it's worth the money there asking for it.
CIAudio VDC-9.0 Squeezebox Duet/Wadia iTransport Power Supply

Other alternative is a DIY PS. Better performance for less money? Any ideas are welcome.

Regards

[Kurt von Kubik]

Hi there

I do not own a Squeezebox duet, but the touch instead.
The Touch is delivered with a small plug in PSU with switc mode technology.
It is rated @ 5V 3A DC output.
I had my touch about a month ago, but I found it sounding very harsh, and irritating. A friend and me then decided to do a few experiments to see if the sound can be improved.
First step was to try out an alternative PSU, for that we tried the nice old Bang & Olufsen lab supply which happens to have a dedicated logic supply rated @ excactly 5V 3A DC, so this looks really nice.
A small chord was soldered together and a 470µF 25V electrolytic decoupling cap was paralelled at the DC input plug, just outside the Touch.

The result was an absolutely surprice.
I´ve never before heard soundquality depend so much on supply as this one does.
Theoretically the reason can also be, that the rest of the set-up is very allergic towards the noise injected from the original switch mode supply, but, at least I do not think it is that way.

Looking at the power consumption, it seems a bit strange, that the PSU supplied, is a 5V 3A type, because I cannot make it consume anymore than 600 mA. But headroom normally is good, but with SMPS it does not really make sense.

The consumption varies somewhat, it swings around +- 100 mA in 2 Hz cycles, which looks as if the processor takes in packages from the source in these pulses.
So a regulated supply is pretty much needed for the Touch.

Another observation I´ve made is, that the sound quality highly depends on the data source. I.e. using the wi-fi option and downloading from a computer, the sound takes on a strange hardness, which I very much dislike.
Using a USB HDD the sound flows in much more natural way, but this does not go for a USB memory stick. The memory stick is also hard sounding.

For all this, I´ve used the SPDIF coax out only and a seperate DAC, as the internal one is of poor quality, the build in is actually an AKM DAC with build in charge pump, driving the output directly.

After this I´ve decided to build my own regulated PSU for the Touch.
This will be regulated with a LM317 regulator and then a noise cancelling circuit and proper decoupling with high quality Panasonic and Evox caps.

Next step is to build a jitterkiller with WM8805´s daisy chained and precission clocks.
Maybe more about this later, if it works.

[jrenkin]

Search the forum a little. there was a recent thread on this and i posted a link to a really nice add on PS that made a huge difference for under $100. I don't have time to look for it now before I go to work. This one took a little work building on connectors and could be modified if you want. It is a linear rather than switching and even my wife, who general rolls eyes at all these things, remarked spontaneously how much better the sound was.

[jrenkin]

Originally Posted by jrenkin

Search the forum a little. there was a recent thread on this and i posted a link to a really nice add on PS that made a huge difference for under $100. I don't have time to look for it now before I go to work. This one took a little work building on connectors and could be modified if you want. It is a linear rather than switching and even my wife, who general rolls eyes at all these things, remarked spontaneously how much better the sound was.

Here it is. SLS-05-030-1T - SOLA POWER SUPPLY, 5VDC @ 3A LINEAR, REGULATED, OPEN INCLUDES O.V.P.

[VT67]

@Kurt von Kubik
Nice write up of your findings.

@jrenkin
The Duet however needs 9V so the PS you are suggesting wont do.

I'm working on a Sigma11 from AMB and a GOLD mini regulator from coffin. As soon as they are finished I will compare them to the stock supplied wal-wart.

Regards

[Kurt von Kubik]

Originally Posted by VT67

@Kurt von Kubik
Nice write up of your findings.

@jrenkin
The Duet however needs 9V so the PS you are suggesting wont do.

I'm working on a Sigma11 from AMB and a GOLD mini regulator from coffin. As soon as they are finished I will compare them to the stock supplied wal-wart.

Regards

TY

What I believe is, that these devices do not like common mode noise, which is exactly what a SMPS is emitting. Btw I don´t think any electronic audio circuit will actually perform better with common mode noise in the supplies.

Good luck with your 9V supply, I hope you´ll experience the same thing I did.

[m461c14n]

Originally Posted by VT67

I'm working on a Sigma11 from AMB and a GOLD mini regulator from coffin. As soon as they are finished I will compare them to the stock supplied wal-wart.

Regards

Hi VT67,
I would love to hear your result for both regulated PSU.
I'm planning to make GOLD Mini regulator for my Onkyo ND-S1 (5v/1A) as well....