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Reid Malenfant
30-05-2012, 19:26
This isn't a biggy, but it may well interest those out there that happen to have the first issue V-Link. As I haven't taken a look inside V-Link II I can't comment.

The V-Link is powered from the USB input terminal, which means it gets it's power from the SMPS inside of the PC it's connected to :rolleyes: That is going to be altered to an external regulated linear PSU.

We all know how much better things sound when fed a nice clean supply, this thing appears to be worth upgrading as I can now hear recordings that sound bad online, the good recordings being quite spectacular :)

Also the only galvanically isolated output appears to be the optical Toslink connection :rolleyes: Again that is going to change, why the hell MF didn't fit a small pulse transformer to the phono S/PDIF output I'll never know. It would have cost pence.


Having taken the thing to pieces earlier there is tons of room to modify the thing, in fact it could have been made about 1/4 the size that it actually is.


Instead of modifying it to give galvanic isolation to the phono S/PDIF output I'll be fitting a superior 75 Ohm BNC connection, though the phono could easily be modded to be isolated I'll not be using it. A bit of track cutting would be needed is about all that would be needed as well as the incorporation of an isolating transformer.


As it is I can just dump this isolating transformer in parallel with the phono output & feed it to an insulated BNC socket. As long as they are not connected at the same time all will be well, & I'm not that daft :D


So in the great Blue Peter tradition here is a pulse transformer that I made earlier, it took about three minutes to wind :eyebrows: It's simply a ferrite bead with two insulated copper wires wound ten times around & through the bead. This thing is way oversize, it could be a lot smaller! I could put 10W of power through the thing at the right frequency, so it'll never saturate. It's sitting on a 5p piece for comparison purposes. The insulated BNC plug (75 Ohm)

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image1-1-3.jpghttp://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image3-1-2.jpg

Finally what it's all about, I'm impressed with the improvement in sound that it makes over what I was using previously - one of these (http://www.ebay.co.uk/itm/FANMUSIC-FM-6011-COAX-USB-SPDIF-COAX-Converter-UK-/260842350875?pt=UK_Sound_Vision_Other&hash=item3cbb6a691b) :eyebrows: Yet that cheap device used a pulse transformer to isolate the output, go figure? :scratch:

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image1-1-2.jpg


Back with more as it happens :cool:

John
30-05-2012, 19:42
ahh that explains why the danmusic sounded better at standard 16bit than the v-link, its only when you go to HD that the V-link seemed to come into its own.
Sounds like what you doing should really help the unit

Reid Malenfant
30-05-2012, 19:46
I have only listened to 16 bit stuff off of the web John (& MP3s that I happen to have on my laptop), but I can now tell the difference between a crappy recording & a good one via the V-Link :eyebrows:

I haven't fed it any HD content as I don't possess any.


I'm not going to diss the Fanmusic as it was good for what it was, but the V-Link is in a whole different league imho, which is why I feel it'll be worth playing about with :D

John
30-05-2012, 21:30
Mark just saying before the mod at 16bit its a bit disappointing Glad the mod has taken it further

Reid Malenfant
30-05-2012, 21:36
I haven't done it yet, but I know it will :) Can't fail, a regulated linear PSU will be better than the laptop SMPS by a good bit.

Only the grounds of the lappy & PSU will be connected, the +VE rail of the PSU will be seperated, it's all that is needed to do the deed :)

The BNC socket is just about getting a uniformally 75 Ohm impedance output, phonos aren't so compromise the signal. If you look at top quality kit you'll see a BNC connector for the S/PDIF.

Reid Malenfant
01-06-2012, 17:10
Well I'm testing this as I type :) I thought I'd better make sure that all is as I thought before drilling holes in the V-Link case :eyebrows:

What I have done so far is cut the track from the 5V rail of the USB connector to the units electronics & placed a schottky diode linking the now seperated bit of circuit to the 5V rail on the USB. I'll install another coming from a seperate DC socket so it can either run on the power from the USB line or if a slightly higher voltage is fed to the DC socket the external PSU will take over.

The pulse transformer is working as expected & the output is at present feeding my Monarchy Audio DIP 48/96 & I'm listening to music, all is well with the world :D

I'll get some pictures up in a bit, more when the thing gets completed :cool:

Reid Malenfant
01-06-2012, 18:45
Piccies :)

A bit of a simple test rig, should sound better once it's back in it's case I reckon :)

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image1-1-4.jpg

The V-Link PCB, look at all that wasted space :eyebrows:

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image3-1-3.jpg

We have lock on the Monarchy audio DIP

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image4-1-2.jpg

Another little something that has now been tested. Not got enough digital inputs on your DAC or whatever? Get yourself one of these & you can have ten extra :) It's a Kramer VS-101AV passive audio & video switcher. In this case it's the video switching i'm interested in as the impedance is 75 Ohms, the same as single ended digital audio.

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image5-1-2.jpg

Taking it in & out of circuit I can't detect any difference in sound quality - jobs a good one :cool: Frankly I didn't think it would as it has a video bandwidth of over 250MHz...


More pictures tomorrow & it'll be back in one piece & waiting for it's new PSU :)

Reid Malenfant
02-06-2012, 11:41
Jobs a good one :)

First picture is the cut track & schottky diode now feeding DC from the USB bus. The diode has a very low voltage drop, so the unit still works as it should. It's there simply so when the external PSU is plugged in, no DC current can flow from the PSU to the USB bus itself.

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image1-1-5.jpg

I decided to fix the BNC connector to the same end of the case as the USB cable. Along with the socket for the external PSU it means every cable can connect at one end, which means it'll go into my rack with no problems at all :cool:

I used some 75 Ohm cable to connect from the pulse transformer to the BNC socket. In this picture you can also see a second schottky diode connected from the positive terminal of the DC socket, it has a similar function to the first. The positive lead is then connected to the input of the 3.3V low dropout regulator. Ground from the DC socket is connected to ground strangely enough :eyebrows:

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image2-1-4.jpg

Back together & at the new business end of things.

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image3-1-4.jpg


One project completed, quite a few to go :doh:

synsei
02-06-2012, 11:59
Nice job there Mark ;)

Reid Malenfant
02-06-2012, 16:05
Cheers Dave, though it's no big deal at the end of the day :)


At least I have ended up with a better sounding USB to S/PDIF converter that will sit in my rack, when I connect the external PSU the fan in my laptop will STFU again :lol:

Just giving it another spin now as I need to get to listen to some music I don't own myself :cool:

Reid Malenfant
08-06-2012, 20:14
I got absolutely everything I wanted in reference to this thread :)

The external regulated linear PSU arrived today along with a Belkin 4.8M USB cable. The length of the USB cable means I'll be able to drop the V-Link into my rack & not worry about it.

The external PSU & possibly the Belkin cable have brought forth much more realism to the proceedings, I'm streaming music off of Grooveshark as I type, same lappy as being used to post on AoS :eyebrows:

Everything is being done by the laptop, it's used for so many things... I can't remember it ever quite sounding like this :D


Why did I do it? Well, in my normal system the output of the Krell DT10 CD transport goes into a Monarchy DIP & then into a dCS Purcell & Delius. It sounds fabulous, but as there was only a single input to the Monarchy DIP it left me a little frustrated knowing I could have better :doh:

Now I could have up to ten S/PDIF inputs to the Monarchy :)

I think the important thing might be that the MP3 stream I'm listening to is processed by this equipment, from the internet it's now asynchronous.


The odd thing is that while spinning a CD from the laptop drive & playing file audio from the net results in occasional glitches, MP3 stuff that is on my HDD results in just music, no glitches :)

Perhaps I'll learn something here, maybe :D

alex1976
27-04-2014, 09:57
Hi RM

Do you remember whether you had any issues with the v-link loading its driver after your modification?
Somebody modified mine with an external PSU and its not locking to windows 7 any longer.

Many thanks
Alex





This isn't a biggy, but it may well interest those out there that happen to have the first issue V-Link. As I haven't taken a look inside V-Link II I can't comment.

The V-Link is powered from the USB input terminal, which means it gets it's power from the SMPS inside of the PC it's connected to :rolleyes: That is going to be altered to an external regulated linear PSU.

We all know how much better things sound when fed a nice clean supply, this thing appears to be worth upgrading as I can now hear recordings that sound bad online, the good recordings being quite spectacular :)

Also the only galvanically isolated output appears to be the optical Toslink connection :rolleyes: Again that is going to change, why the hell MF didn't fit a small pulse transformer to the phono S/PDIF output I'll never know. It would have cost pence.


Having taken the thing to pieces earlier there is tons of room to modify the thing, in fact it could have been made about 1/4 the size that it actually is.


Instead of modifying it to give galvanic isolation to the phono S/PDIF output I'll be fitting a superior 75 Ohm BNC connection, though the phono could easily be modded to be isolated I'll not be using it. A bit of track cutting would be needed is about all that would be needed as well as the incorporation of an isolating transformer.


As it is I can just dump this isolating transformer in parallel with the phono output & feed it to an insulated BNC socket. As long as they are not connected at the same time all will be well, & I'm not that daft :D


So in the great Blue Peter tradition here is a pulse transformer that I made earlier, it took about three minutes to wind :eyebrows: It's simply a ferrite bead with two insulated copper wires wound ten times around & through the bead. This thing is way oversize, it could be a lot smaller! I could put 10W of power through the thing at the right frequency, so it'll never saturate. It's sitting on a 5p piece for comparison purposes. The insulated BNC plug (75 Ohm)

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image1-1-3.jpghttp://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image3-1-2.jpg

Finally what it's all about, I'm impressed with the improvement in sound that it makes over what I was using previously - one of these (http://www.ebay.co.uk/itm/FANMUSIC-FM-6011-COAX-USB-SPDIF-COAX-Converter-UK-/260842350875?pt=UK_Sound_Vision_Other&hash=item3cbb6a691b) :eyebrows: Yet that cheap device used a pulse transformer to isolate the output, go figure? :scratch:

http://i939.photobucket.com/albums/ad240/speakermark/Audio%20Video%20system/Image1-1-2.jpg


Back with more as it happens :cool:

Greg2010
27-04-2014, 10:35
Hi Alex,

Mark hasn't posted on AOS since last Feb, so hopefully someone else will be along with experience on your issue :)


Regards
Greg

User211
27-04-2014, 12:30
Alex - if it is broken I have another for sale in the classifieds.

alex1976
03-05-2014, 22:53
thanks a lot - its probably beyond repair after its modification....if someone wants to experiment with it or wants it for spares i am happy to post it.
I just received a Gustard u10 and will try to get that one to work....

User211
03-05-2014, 22:59
Actually I used tp have trouble with mine and a Tri-Vista SACD DAC section. I just tried it with Paul's (RFC) Accuphase and we got about 2 seconds worth of sound out of it after multiple attempts. I am going to bin it - so no longer for sale.

nat8808
04-05-2014, 18:10
If I sent postage money, do either of you (perhaps both?) fancy binning it my way via the post?

I was thinking of modifying something like the V-link to output directly to a DAC rather than S/pdif - for use in experimental DAC projects. Or I might of course be able to put the two together somehow to make one good one?

User211
04-05-2014, 20:45
Nope it went down to the rubbish tip earlier I am afraid. Soz.

nat8808
04-05-2014, 21:48
Oh... I'm against that sort of thing! Shame on you...

Then again, it's only when people throw things away like that that I find them myself and discover they work ok, with a connector resolder or something.

Did you try that? Could have just been a dodgy connection on the usb or s/pdif socket.

User211
04-05-2014, 23:42
No I didn't have the need for the thing anymore. No one wanted to buy it - it had a chance at least in the classifieds.

RIP V-Link.:( Actually, good riddance V-Link. Never did think it was up to much. More pain than gain TBH.

alex1976
06-05-2014, 06:35
let me send it to you - PM your address - you can send me postage once i know how much it was. or drop by near E1-home or EC1-work.
kind regards
alex

nat8808
06-05-2014, 11:16
let me send it to you - PM your address - you can send me postage once i know how much it was. or drop by near E1-home or EC1-work.
kind regards
alex

Cool, thanks for that - I live near Morgate tube EC2 so perhaps I could even pick it up from you? I'll PM in a sec.