Mf X-act Dac

Hi all,

Have just seen this on eBay and it looks tempting: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=3272&item=7515467024&rd=1

What do you reckon the improvements will (if any) over my NAD C521BEE's DAC? Will be using with a Yamaha HTR-5540RDS amp and Mission m70 speakers. I like a 'warm' sound with plenty of detail and bass punch - does this DAC offer this?

Thanks,
Neil

 

I've just got this the other week - it's made a great improvement - I mearly use it with my nad amp and my yammy cd player!

give it a go I would say...I paid 155 for mine!

 

It's at £67 at the moment with an hour to go, so will be bidding in the last minute or so.

 

mf in the old series made 3 dacs

the first was the xdac, hdcd
second the x24k, 24 ibt, apparently the xray in dac form

I tried the 2 briefly, tiny difference, I thought the x24 better but negligible

never got an x-act, the cheapest of the 3, being mf, it will be good,well made and designed, but will it upgrade?

 

Not sure to be honest. Worth a try though. I like the idea of HDCD too, as I have a number of HDCD remastered CDs.

 

Won it for £82 plus £7.50 P+P!

 

wow, thats agreat price..! if you don't like it, then you could sell it on, you may even make a profit...seems that the best time to end an auction is in the evenings..!

 

Sorry to piss on your parade, but it'll probably offer no improvement whatsoever. Its a rubbish dac IMO

MF were very clever and simply stuck an ancient 18 bit dac with some of the cheapest op amps they could find in a nice case and charged people £150 for it!

Very, very bright sound as well.

DT

 

which dac and opamps did they use for it dt? I don't think its hdcd either, only one that was was first, xdac.

 

The problem with these X-dac series is the nasty wall wart...feed them with a good 12v ac from a big tranny and you get them to sing ....plus swap out the cheap opamps but there in sockets so no pain there.

 

It's an X-DAC 1, so is HDCD. They used an 18-bit 'Co-phase' Burr-Brown DAC. Will maybe look at modding it when I've had a good listen for a while and see what I reckon of it.

 

that's quite a good one, the earlist mf x series dac, not the same as xact.

check this out for interest

http://www.zeuslab.newmail.ru/MF_XDAC.htm

 

Doh - sorry, meant it was an X-ACT DAC. Got that wrong.

 

its ok, xact isn't hdcd, could you inform as to the dac chip on this please? if you open it up, don't do the front panel, its the rear one, undo all the srews/allen bolts, and gently but firmly slide the pcb towards you, should come quite easy

 

Hi Data,

Haven't got it yet, but when I do, I'll try and remember. Might give MF a call tomorrow if time allows and ask them.

 

Data your wrong........if its like the X-dac that I have in front of me !

You need to follow a rigid path to open the unit.

1/undo the front panel...gently with draw it and un plug connector for the leds

2/ undo the rear panel ....slide back plate and pcb out.

If you try without removing the front connection you could easily render the unit usless.

If its not like the X-dac ..........

The zeus site seems to have missed a trick or two ...I know they have re done the psu with a new board, thats all well and good if you have the new pcb made up or have the ability to make one at the drop of a hat.

replace the stock diodes for 11DQ10's best penny for penny change!
replace all the small electrolytics with oscons[ the ofc leaded ones]
by pass all electrolytic caps with on 10% of its value. replace all the larger resovoir caps with stargets or better....for a start just alter the type latter you can mess with the values. Replace the opams with a decent BB one 604 series or better. Replace all signal path resistors with a minimum of Holco, but vishays and rodestiens are better. replace the three rca sockets with the best you can get !
copper foil cover all Ic[don't touch the pins!] and drain to a star earth point.

[Maybe do this first.....!]
Draw breath have a listen .....beg borrow steal a big square frame 240-230 vac to 12vac transformer sort of 100va make a decent mains lead using a screened cable suitable for the 12vac. Make Merlino [TNT] or similar for the transformer to wall socket. . Sit back and listen to the thing get its rocks off !

 

I was doing it from memory, its months ago i don't recall doing the front panel, but I didn't think it was necessary.
Could be wrong, obvisouly am, apologies, you need to really get in close with your eyes to check for connections of couse, after opening up, before moving anything.
if you go to burr brown and look at the pcm69 datasheet, the xdac is almost a direct copy of the one at the bottom, with a few small changes.

http://www.digchip.com/datasheets/parts/datasheet/477/PCM69.php

 

which one would you recommend then..?

 

Sorry data didn't mean to sound snappy !

Thanks for the data sheet refference!

Well I picked one up from a surplus place but .....well rs have a few. Give me a while and I'll see if one looks like the jobbie you need.

 

Oh yes .....don't forget the digital IC ....plays a large part in the percivved sound.

If you need a Kit .....let me know I've now got Four different flavoured cables plus a straight silver .....max cost of about £20 [as good as the "dark art" from ML] the straight silver is probabley better thinking about it ! Thats not saying the dark art is bad which it certainly is not. Just could not tell any difference between mine and theirs [except for the seventy pounds price difference ]