SOLVED V-dac sunday playtime mod

Time to don my magic foil hat and use some of these left overs for the hell of it... and im not spending the day trying to find the original case

already ripped the tacky phono sockets off and hard wired a decent cable.
also removed the led`s because they emit tons of noise.


Emi shield the crap out of everything.... wooo








time for a layer of insulation.... roll out the tape!





time for some foil hat and drain wire.... where my tin foil hat




roll out the tape again


time for some copper mesh.... my secret weapon






roll out the tape! lets cocoon this thing... hah harrr!


bit of sleeve on that drain wire


meter says tip positive... 12v 500ma... computer says yes!



just soak test to see if it burns down my front room and i`ll give it a try

think i`ll go make pizza now.... yum yum

Turned it off and shoved the probe in. It was around 36'c so I think my front rooms safe from burning down. Lapies playing files to keep it working instead of idling.

I already did the xmos chip etc on the V-link last week... I think it squeezed a little more focus out.





Edit: so with both these running with each other im expecting a nice little budget computer audio set up.... pick a laptop and off you go

Subscribed

yep they get on just fine. all I need now is to whip out my prayer mat and plug it into the hi-fi



see how it goes...

EDIT: In regard of the EMI ferrite polymer resin in some cases it does more harm than good as it can reflect the EMI back into an IC and such. in that case you need to listen out for a tell tail brittle quality to the higher frequencies. its a indicator you dun made a boo boo

not my day for hoarding left overs

got a lot of not much useful there. a fractured bullet plug... crushed pins... missing grips and sleeves.

and lots of lovely 5pin dins that im trying to find a replacement for in this instance.

think i`ll have to do something horrible to that old reference cable (sorry Dennis its board modding sunday )

you cant buy echmans bullet plugs at half three on a sunday... worlds full of such horrors



time to get brutal

----------- INTERLUDE -----------

I lied and shoved chicken in the oven instead... it was less effort
shot of rum to settle my de-solder nerves (optional extra)
my mouths already on fire from peri peri extra hot sauce


I know... I know... who wants to live forever


practice my mantra. clean soldering iron, tin soldering iron, shake off excess, quickly de-solder before the flux burns off, pull the solid core wire, apply iron for about 1 and a half seconds.... prey!
three seconds and you need a new plug because it will melt. lol

these plugs are designed to be soldered once if you have skills

please work! please please I repent!


ground off no melted plug


I win round one \ / woop!


rinse and repeat...


yeay!


well thats 50% of the battle... hope I can solder them back again... best keep my prayer mat out just yet

Oh joy here we go then.... mission impossible. lol

prep and tin the solid core (with mantra )


getting it sorted... not too much melting (even though it does look like its been soldered by a blind rhesus monkey - close cousin of mine )




get the sleeve, grip and grub screw back in before it all falls to pieces


matching set... not sure the left and right channels are correct after cutting the 5 pin din plug off. but its a 50/50 chance



now that I can plug into the spare valve amp... once I unbox and set it up that is.



so i`ll have a minute then get set up and see if the modding gods love me or not

Well thats a lack of spanner and manual in the works

I need to swap out the katan back plates to get bridged single passive wiring

amp say no unless you mod the speaker cable yourself



cheers linn for the fine speakers with extra nut ache nuts to have to remove without chewing them up.... then theres the deck of pcb cards behind that further causes various aches

I should maybe find the manual on google-fu (assuming anyone ever uploaded it )



Oh well... a board sunday modders gotta do what a board sunday modders gotta do (in a Johny Wayne voice)

EDIT: Coke taste test

Coke A?


or Coke B?


I feel lucky for coke B both facing outwards. seems like the idiot proof option... and I qualify

EDIT: aha one has found an online manual... not that its clear as mud or anything lol



I gets it

amp all blowed up? negative



speakers all blowed up? negative



dac all blowed up? negative



sounds very promising.... have to get it set up properly somewhere

Sunday modtastic

-------- Summary ---------

Its darn fine actually. very focused, layered and punchy sound with some great underpinning without getting wooly or blooming. throws the image about with confidence too.

A good listen for the parts involved. I is happy bunny \ / woop!

EDIT: I just need to get that drain wire to the power supply chassis ground and I think were done

heres a terrable recording from my phone just to finish off

View attachment rec.zip

edit: nice to see some pretty valves glowing again



I even fluked the 50/50 on getting the channels right. lol
ghetto modding gods shine on me today

Final touch...


I found some appropriate colour bell wire. so I multi stranded it up to make a tempting drain path.




attached it to the drain wire.




and plugged it into the ground terminal of this spare battery power supply.





now its plugged in and switched off it should provide a decent chassis ground to earth.


Now I just sit back and enjoy my V-dac`s second birth


EDIT: Ooh now im thinking two usb dacs for films?
wonder if I can make it happen and have rear speakers for the main system... more pending fun \ / woop!



edit2: now its had time to warm up and I can wonder room from room between budget and reference systems. with the added benefit of it being fair game`o clock on noise this time of day
its all good on the basics. it gets the music over... I dont think the most obvious weakness of timbre is fair to pick at given the immense price tag difference. if it doesn't cook im happy

(Im not doing that earth to the radiator in the room thing again... tried that by accident across both my arms... made my hair curl a bit. )

Well I tried a spare custom linear psu and it sounded better still except somethings very wrong with the linear. lots of high frequency noises which a few watts soon mask but the point is it shouldnt be there. fair to say that linear needs a trip back to the USA for fixies.
it would be an improvement (sounded more natural in tonality) but if its squealing through the tweeters then thats not fidelity. maybe a cheap dac wide bandwidth linear type issue.
I unplugged everything but the dac and amp and it stayed so its nothing stray from the computer end.

Edit: I have another linear that works fine so I may try that just to see if the situation arises again...

So i've gone molex on both the linear psu`s so I can quickly switch out and see if I can shift this high frequency artifact to be honest at seated distance set up in the room you wouldnt hear it at all with any music. but I want to try and get it reduced some more

molex the bench psu... that gives no trouble.


molex the expensive slightly tired linear... that is offering improvement with added truths mayhap


ready to plug`n go


decided to bring in the 16v line level switching unit to see what effect it had.


now the signal regarding its strength and artifacts have moved on in clarity what fun...

edit: could have been my emi polymer resin overkill... could be the amp or the linears grounding (signal and chassis ground bog up)... or just because the v-dac is low budget and trying to make it punch well over its price bracket shows its weakness.

or all of the above... I`ll take it all to another system and see how it behaves

edit: Go try it on the mid range system. see if the pre & power amp show or reject it...



find out soon....

well I decided to shield up the power lead while it was playing low with the various noises the prominent part of the overall sound.

as I suited up with shielding various frequencies of this artifact started to fade away.

now its just one constant single high frequency tone with no phase or harmonics. cured 90% of the problem so im playing nicely


foil and insulate the connectors...


bit of EMI sheet...


foil `n drain wire...


foil wrap time...


insulate...


couple of ferrites and a nut on the case screw to ground...



time to emi those remaining gaps... why not... (other than temperature mayhap )



only need dig coax and power cheers.... lets bury the rest


wrap up...


dum de dum... la la la...


now lets see how we get on

edit: I can pick up a ground loop suppressor for £5 or £10 pounds to filter that last frequency off. then it will be 100%... at least until in mayhap boils to death in its own juices



^^^ one of them jobbies

Shoved my ferrites on the linear mains power in and on the 12v dc out (both ends)

tidied that ground wire with a bit of sleeve two...

shielded and used braiding for the last length of 12v dc power. makes it more plug in friendly as it still bends



just buy my ground loop isolator and im out of ideas

edit: it is a ground loop issue. the longer the systems running the more it settles. be me that messed up by not grounding the pcb at the appropriate point. I may be able to manage it through a shield on say the usb input (thats not in use anyhow)

have to test it out and see. probably just the cheap dac`s inherent floor... seem to remember it was a pain for it even new and un-tampered with. but hey it sounds a hell of a lot better given every possible chance I threw at it... so I call it a win. (unless it melts )

Final prudent move.

Something in the back of my mind keeps saying "dont leave a valve amp and abused hot running dac on a fabric covered chair... you dippy tonka"

So I went exploring in the cellar for something cool and inert like a spare one foot floor tile





that should save me from burning my front room up

Edit: I can also start tuning up the laptop. turning turbo and EIST seems to do instant wonders for every motherboard ive tried it on... assuming audio is your priority anyhow. turn off any un-used usb port channels may help the latency. shut down services and programs I dont need. you can spend hours poking and prodding... its become a tedious drill routine.

temp check... dum de dum...


oh lovely


clean bill of health

Edit: well I cant see as the original was ever case grounded... neither side of the pcb was in contact and the cut outs cleared the usb and switch. as for the original phono and optical input the end plates screwed into the plastic so that didnt ground it either.



its one razor sharp equal frequency both sides if I move my head around slowly there's no phase. it cancels both side instantaneous the moment you hit that sweet spot.

this is at about three foot from either speaker and its hard to detect the moment you use a few watts on a signal.

sneaky inexplicable frequency

had just enough to do it all again as a floating shield for the xp mostly




worlds most shielded up V-dac award


can always weigh it in if it burns up

update: left it running all night and no melt down... still chewing zeros and ones and spitting music. likes its power supply that costs three times more than the dac (runs cooler than the bench supply)



the sneaky high frequency tone has decided to take up residence mostly on the right channel and its lowered to less obtrusive levels. (good power meets inadequate dac scenario I think )

Edit2: Tweaked out the laptop the 1000μs you can knock off... thats the win8 kernal reporting wrong (known bog up )




and I shoved a silver core usb cable to complement the same silver coax design on the other end of the usb converter.




its focused up, smoothed and gave space to the upper register notably.
the phantom tone sounds cleaner and fainter still

be nice if the bios wasnt so limited... I want it to run the cpu at a constant 2.6GHz

have to look into that

by far the noise from the hard drive motor is the primary noise pollutant followed in second place by the laptops cooling fan... so mystery high frequency tone comes third with amp hash background noise in fourth place

----------------

well I tried these lesser speaker cables (that come with the fatman VII ) that was a clear step down in quality.





then I tried the bottom posts instead of the top and that seems to have settled the high frequency tone and gave the tonality a kinder character... bass drivers can get a bit flustered by modern standards so its the weaker driver really.

Edit: Thats gave it all more to do and may benefit... using a foobar DSP to up the signal to 24Bit 96KHz and some album gain so the CPU is running faster along with the speeds of everything else en route to the amp.



I can be a dirty upsampler if it helps

ooh it did help... high hats... ride cymbals... etc all sound less brittle and improved rhythmical drive. took the edge off brass and vocals. my dancing feet are firing up now ^_^

full speed ahead and stuff the icebergs! lets force 192KHz




Punch it Chewey!



party time

note: I just tried the pc upsampling on the reference system and the moment I started using DSP and up sampling it seemed a fraction less focus an depth. so just shows you never know what may end up with as best