MDAC first listen (part XII)

[fred sonnen]

Hallo John

Q4/2012 is almost here. Thats the time Creek DAC/ Pre is expected.
Am I right?
Would not that be a good opportunity to take on more technical details and features, setting?

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regards
f.s.

 

[bigmarcelo]

I would expect it to see off the Akurate never mind the Mjik.

I'll be able to do a comparisson at home for that .... if it does..... I'll be tempted to sell the ADS and upgrade the amp ...

 

[bigmarcelo]

No, to evaluate the MDAC upgrade I switched back to v0.96. It's the version I know best. Although I do think v0.90 and v0.96 sound pretty much the same.

I tried all version that have been released yet. Tested most of the new options (discrete remote codes, dimming, ..). Prior to the MDAC upgrade I was playing around with Phase Normal/180deg and Full/Partial D3E.

At least twice I thought the new versions sound better. Every time I returned to v0.96.

What I really have to try: XLR cables between MDAC and my CA 840W power amp, XLR attenuator cables (Volume is set to -30 to -45 most of the time) and a balanced power amp (MAMP)!

Michael

what's the difference in SQ between full and partial 3DE? what is 3DE supposed to do?

I leave mine in full, as recommended by John, but I actually don't know what it does.....

 

[JohnW]

JohnW, you have email

Hi JTC.

Got your Email,

Mentally, I've said to myself that yours, a unit for Simon & Sams are the last units I'll update at the moment.

I'd rather wait upon feedback from the owners of the currently updated MDAC's hopefully over the next couple of weeks - Fusion has already post some comments.

Naturally I'm cautious, as I don't want to upgrade a batch of units only to find that owners are not happiest bunnies with the resultant SQ!

Its like redecorating someone's house without guidance - everyone has there own preferences... I can only "redecorate" to my own style and hope its generally accepted - black wall paper with "lovely" crimson pink ceilings is defiantly out!

Its one thing to design a product with your own design "ethos" - people have the choice to choose - but once they have chosen and then offered "blind tweaks" based upon the trust of the designer "ear" then it becomes a much greater responsibility; one I'd personally be a little happier to make if my reference system was functional... I'm just erring on the side of caution

The other issue is I'm now running out of the other components used for the update - the update involves changing about 30 components.

Lastly its a time issue, its takes about 4 to 5 hours to complete each update - which is OK when I need to relax and take a break from the slog of designing, but now after updating 7 units its getting just a little tiresome Yes I know I did it too myself!

Really, the intention behind the upgrades was to take a second look at the design to find areas that can be improved and tweaked - with the aim of developing these to maximise the performance of the MPAX upgrade by the time the MPAX is released I hope to have a small team employed here in Czech who will manage the updates and servicing etc...

John

 

[JTC]

Hear you loud and clear, John. There's no rush on my part, if you send me a reply to the email that'd be great, although others might be keen to find out whether their MDACs would need to be sent back to you a second time when the MPAX is ready....

All the best!

 

[fusion5]

24 hours have passed, time to listen to some music!

 

[sam_cat]

Keep tabs on the tracking details for my M-Dac it looks like its about to be delivered to JohnW.. Feels like forever that its been away.

Sam

 

[steve-g]

I got one of the early M-Dacs last December and have recently discovered this forum (I was looking for firmware updates). Like everyone else I've been trying the various firmware versions and have settled on 0.96 - this fixes the momentary loss of lock that occurs on some inputs but still sounds better than the later versions.

I do have one minor problem with my M-Dac, one channel of the headphone output (the right I think) has a highish DC offset (~45mV) my headphones are low impeadance (32ohms) so this is audible when the headphone are plugged in / removed. Is this something that I can adjust? - it's probably not worth sending it back for this to be fixed.

Steve

 

[JohnW]

Keep tabs on the tracking details for my M-Dac it looks like its about to be delivered to JohnW.. Feels like forever that its been away.

Sam

Hi Sam,

Your units arrived this morning,

John

 

[JohnW]

I got one of the early M-Dacs last December and have recently discovered this forum (I was looking for firmware updates). Like everyone else I've been trying the various firmware versions and have settled on 0.96 - this fixes the momentary loss of lock that occurs on some inputs but still sounds better than the later versions.

I do have one minor problem with my M-Dac, one channel of the headphone output (the right I think) has a highish DC offset (~45mV) my headphones are low impeadance (32ohms) so this is audible when the headphone are plugged in / removed. Is this something that I can adjust? - it's probably not worth sending it back for this to be fixed.

Steve

Hi Steve,

45mV high, our upper limit is around 10mV - 45mV will cause no damaged, but its better to understand why its so high.

What has been seen in rare instances in the past is the Wima Polypropylene capacitors can go leaky. Since the introduction of lead-free solder the soldering temperature has had to be increased quite dramatically to meet the Non-leaded solder's higher melting point - this stress all film capacitors so its not just a problem for Wima.

Its rare, but when we see DC offsets, the Wima's are our first suspects.

Or it might just simply be that the factory did not trim the offset during production - but due to the Cross-coupled output stage a test jig is required to correctly trim (there is a trimmer for each output phase, but trimming one arm effects the other; the jig isolates each arm allowing you to independently trim each arm to zero).

John

 

[sam_cat]

Hi Sam,

Your units arrived this morning,

John

Excited now!
Pack of opamps tucked in one of the slots in the polystyrene as well.
Once its ready to return home let me know how much I owe you (and include enough for a couple of beers/ some wine for you and Renata)

Thanks,
Sam

 

[sq225917]

John, If you're just doing the mainboard pcb for me then I can easily send it round to other owners so they can try it out. It's only a 8 screws and two cables job to swap it over. I can even put a little video on-line showing how.

 

[steve-g]

Its rare, but when we see DC offsets, the Wima's are our first suspects.

John

Hi John

Thanks for the rapid response - when I'm in the right mood I'll take the lid off and have a look a) to see if I can spot them and b) to decide if I can replace them with my kit.

As you say it's not serious, just a minor annoyance.

Steve

 

[JohnW]

Hi John

Thanks for the rapid response - when I'm in the right mood I'll take the lid off and have a look a) to see if I can spot them and b) to decide if I can replace them with my kit.

As you say it's not serious, just a minor annoyance.

Steve

Hi Steve,

If your technically competent, then I'm happy to give you a call and talk you though the procedure...

John

 

[JohnW]

John, If you're just doing the mainboard pcb for me then I can easily send it round to other owners so they can try it out. It's only a 8 screws and two cables job to swap it over. I can even put a little video on-line showing how.

I'll send you a complete unit...

John

 

[finesensations]

what's the difference in SQ between full and partial 3DE? what is 3DE supposed to do?

I leave mine in full, as recommended by John, but I actually don't know what it does.....

There is a short explanation in the User Manual and John recently expanded on it but I can't find the post (if anyone can find it please provide a link) and don't want to miss quote John.

I believe most people set it to Full but as it won't do any harm to your M-DAC why not just try it and decide for yourself.

 

[strummer]

Apologies if I've missed something obvious, but is there an up-to-date list of available Upgrades? IE, a simple list in one place, without having to trawl through 30 pages?

Is there a better external PSU for sale?


My initial comment after 3 days is...it's OK, but not sure it's quite as good as the DAC I was using, which has 2 toroidal transformers supplying it (just never got round to putting it in a Box ).

I don't have any electronics knowledge whatsoever, but doesn't a decent PSU always improve on a Wallwart?


ta

 

[fusion5]

There is a short explanation in the User Manual and John recently expanded on it but I can't find the post (if anyone can find it please provide a link) and don't want to miss quote John.

I believe most people set it to Full but as it won't do any harm to your M-DAC why not just try it and decide for yourself.

http://www.pinkfishmedia.net/forum/showpost.php?p=1779208&postcount=362

Most of the time I use a volume setting of -30 to -45. After reading Johns explanation I decided to give the partial setting a try. Couldn't make out any difference though.

 

[finesensations]

I have revisited 0.90 firmware for couple of times now. I would like to just say that its the best one. and i tried so hard to agree , but here is my subjective findings:

0.90 seems to have the easiest to listen to sound or nice an smooth laid back sound. You cannot go wrong with it. It won't bite you.

It has wide stereo image, but i think that sometimes it can sound a bit flat. Analog sounding, yes, maybe, but everything seems to sound a bit too smoothed out (smeared?) especially for electronic music. Many of them effect sounds used in the genre (if you know what i mean) are not perceived in the 3d listening stage, but just panning l<->r between speakers.

The bass is nice, but dunno if it is fully extended. The rhythmical of the bass side is handled well tho and the bass is firmly placed in the sound image. I think that it is missing some of the definition and air that the later versions have.

0.99 has totally different bass and it seems to be as wide as the whole sound image. Bass without proper firmness and placement cannot sound good.

What finesensations suggested (A.05, partial d3e, 0 deg) sounds ok. It has more space and air, the bass is firm and placed properly. The difference compared to 0.9 can be described with analogy of watching a movie few rows closer. The sound stage surrounds you better. The bass (impact) could maybe be just a tad lighter, but it sounds fully extended and well balanced with other instruments.

I was and am totally happy with the 0.90 but i also like the extra "sharpness" or definition in some of the later versions.

Hi Elviz

Thank you for giving your feed back on v A.05.

We appear to be in broad agreement but I would give it more than just an 'ok', probably at least a 'very good'.

I believe the bass is more/fully extended but upper bass is slightly lighter which I prefer as I use my system for all audio output, including Speech.

What version do you normally use/prefer?

Or do you chop and change depending on what you are listening to?

 

[steve-g]

Hi Steve,

If your technically competent, then I'm happy to give you a call and talk you though the procedure...

John

Well I was an electronics engineer (control and instrumentation) before I retired and while I have the basic test gear and tools I don't really have anything to handle surface mount bits - the nearest I have is a 1mm soldering iron bit!

The eyesight is not as good as it used to be either - some of these bits are ludicrously small.

Or were you refering to the offset adjustment procedure?

Steve