Another EBay DAC or Not

[Pingushome]

Originally Posted by colin.hepburn

Well yes but at some point I want it all permantly wired in so switch makes life easy I may as well do this when I case up the dac

Hi Colin,
been looking for a usb dacfor the computer and found your thread so took a look.Seems like a nice board. Another project in the making
You may be able to leave the TE7022 board in place for the usb and switch it in and out via the switches on board (the two red switched above the board). If you can, then a short extension to a case monted switch or sub board with a relay may be your answer. It may then not default to usb even if the usb is plugged in ??
Crude but simple.
Martin

[colin.hepburn]

Hi martin
You should look at the AK 4396 DAC as well I think most of us on here and audio talk who have a Diy dac have this one as it is a very good sounding dac which we all agree on and it’s easy to tweak to look for the AK4396.USB version if you only want usb other Wise this is the link
http://www.ebay.co.uk/itm/110686449376?ssPageName=STRK:MEWAX:IT&_trksid=p398 4.m1438.l2649

The red Dip switches on the WM8741 Dac are for the coaxial output for switching between 44k and 196k the other is for optical to coaxial select


I think I want to add a switch for the usb but as pulling out the usb cable leaves the socket open circuit allowing the other inputs to work so the switch would have to switch all four tracks on the board or would just switching the VBUS and DGND lines work but that would leave the D- and D+ line live from the computer as the computer is still powered up see usb cable plug diagram for wiring plan

[Pingushome]

Hi colin,
Did not have that pix of the layout, now I see what you mean. Think you may need to switch all four chanles just to be on safe side, just so long as there is no sensing terminal in the usb socket that knows when things are plugged in. (even when not switched on ).
Picked up a pink triangle ordinal on ebay for peanuts years ago and have used that dac, but now a second system is taking shape I will look at the DIY dac £25.00 got to be worth a try.
Thanks .
Martin

[colin.hepburn]

Yep will have to way until the postman brings it and see what I can do but may just leave it as is I think
Yes the AK4396 DAC is very good cost me about £50 all in plus I added the buffer and the regulated PSU i sent you the manual for
It sounds even better to me with the buffer added
http://www.world-designs.co.uk/forum/showthread.php?t=6315&page=4

[audiopete]

Originally Posted by colin.hepburn

Hi Pete
Yep but what I need is flexibility i.e. coaxial +optical and usb but this is secondary plus my budget is limited but luckily the psu I built for the still very good AK4996 24bit DAC can be use for the WM8741 as well so big savings there
I also see that most of the big audio companies are using the wolfson DAC in their products the likes of NAD/ Cambridge audio Marantz rega and many others so should be worth a go

Hi Colin, all

Sorry for delay in replying technical error at my end.

Concur on the wolfson Dac, I am pretty sure one of my earlier devon dvd players had them, sounded good.

I have tried both the optical/coaxial and much preferred optical, never tried USB. Although did do a far amount of googling on the USB vrs coaxial/optical, in the end just stuck to the optical option which is via my macbook pro to my ebay sourced Dac board which has optical and coaxial selected via a jumper on the pcb.

Some of the prices you see for dacs pcb makes me wonder on the price/value on some of the commercial offerings.

[FreddieT]

Ali,

Can you enlighten me with any details on the valve based enhancements made to your AK4396 DAC (did I miss it on another thread?), please?

Anything that outperforms the Rega and doesn't cost a fortune must be special indeed. I'll be interested in Colin's experience with the Wolfson and whether it will respond in the same positive fashion as the AK based module.

F.

[colin.hepburn]

Hi Freddie
Can’t speak for Ali.s Valve output AK4396 DAC but I am sure it will be very good my AK4396 Dac is using a FET output buffer and I can say it is very good indeed with the FET I have still to try a valve output stage on this dac yet
The Wolfson WM8741 is still on the slow boat to the uk But as it’s a voltage output dac as is the AK4396 then it will lend its self for the same modes I intend to just try a couple of other op-amps first then try the FET Buffer and the valve buffer on the WM8741 as well
Maybe Ali could help both of us here could you post the valve buffer schematic you used Ali

[colin.hepburn]

Well that’s the New Wolfson WM8741 DAC on the test bed and working fine
This dac is not the one in the eBay image with the four op amps but is the clamed new version 1.9v with only the three op amps the two single output opamp have been replaced with a dual
At this point it has only a hours run in with the S/PDIF input but its sound is very good from the off is it better than the standard AK4396 well to early to say but it is very Close to the point I would say the wolfson WM8741 has the edge over AK4396 but time will tell when I add the buffer stage but for now it gets the thumps up

[Ali Tait]

Originally Posted by FreddieT

Ali,

Can you enlighten me with any details on the valve based enhancements made to your AK4396 DAC (did I miss it on another thread?), please?

Anything that outperforms the Rega and doesn't cost a fortune must be special indeed. I'll be interested in Colin's experience with the Wolfson and whether it will respond in the same positive fashion as the AK based module.

F.

Sorry, missed this. Lots of info here -

http://www.audio-talk.co.uk/phpBB2/v...er=asc&start=0

[Pingushome]

Hi Colin,
Have a feeling the dac board may be on a slow boat for Christmas, daughter has been extremely inquisitive about it and has now gone very quiet
So maybe my dac for the computer has been solved, we shall see now I'll have to get the Brice head phone amp psu working
BTW Maplins have a 60 watt temp controlled ESD soldering iron reduced to £40.00 until end of Dec 12.
Martin