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MDAC First Listen (part 00111001)

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Johnw,

As stated before i'm interested in devdac + streamer for testing/debug.

Have you an idea about the PSU i can order ?

We have also discussed about the loan of two amps to replace my eclipse small amps.

Bests

Hluga,

Thank you - I'll add your name to a PCB set.

I did Email the PSU company in HK but they never got back to me, so I'll try again or find a different more local solution - if you know of any 12Vdc 1A PSU "solutions" during your internet travels....

Noted about the Amps - and the DEVDAC has balanced outputs which can drive these amps directly.
 
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Or buy something that is available now rather than wait another 5 years....

Wash your mouth out.

Where the hell would we be if people went out and did things like that? Next you'll be suggesting that potential customers will go into Hifi shops and have a look and listen to products before making a decision. Utter madness if you don't mind me saying.

Doing that people might end up with a Hifi system that sounds incredible and looks good in a home setting. Why would they do that when they could wait for something to turn up to be shoehorned into an old component case or a plywood box?

Then there's the problem of having to listen to music for five years when they could be fannying about on the internet's maddest discussion


As I say, ridiculous suggestion. You'll have Hifi done away with.
 
Hi JohnW,

I am trying to figure out what it is you are trying to do here with these 'development kits'. What exactly are you expecting the people who buy these kits to do with them?

Do they develop new software component or just test software that is on the kit or pushed onto the kit? Do they do listening test or functional testing and give you, and us, feed back? Or is this just a way to raise fund by giving people early previews of what you already have designed? Or all of above? :)

WRT software I hope both will take place - testing and feedback on the our "OEM" software and also 3rd party software installations on the streamers RPI "heart" - I encourage both, and we will offer all the support we can.

So, Yes very much ALL of the above - I need to start funding the purchase of "production" component stock - as full SMD reeled stock is typically 2K to 5K Pcs. we need to purchase 5K pcs of each component - even though we might only produce 100pcs MDAC2 etc. so the solution is to offer as many common designs as possible - the 100 "at cost payments" does not pay for the total stock that needs to be purchased - so funds from projects such as DEVDAC and the Mini Streamer are intended to help bridge the funding gap.

1. We start to ship "units" so we are preparing ourselves for higher quantity items such as the MDAC2 etc. We are putting the logistics in place to handle outgoing shipments, packaging & paperworks etc.

2. A more staggered approach to increasing the production rates - more hands on experience on the SMD line etc. - without the pressure of a 100 odd boards that might need rework due to some unforeseen production related issue on our side.

3. Exposing the bottle necks we will face (such as production space) - it might not sound much, but even a single extra bench added upstairs in our listening area will make a dramatic difference - at the moment we are working on the production boards on our lab benches which are more for R&D then production - I'm coming to appreciate the importance of the different requirements. Being able to manufacture PCB's / units without interrupting R&D is important as we move forward.

I've now purchased the equipment for the production bench ( I cannot say its a production line as we only have a single bench). Once the MDAC2 orders have been met, we only plan small "bespoke" designs so 10 - 20 Pcs a month to keep to boredom of retirement at bay and producing "personalised" designs I believe in.

Also, how and when (a final date for end of testing phase) is all this going to be concluded, resulting in a version of MDAC2 any time soon?

The MDAC2 DD2A will be the first "MDAC2" upgrade design to be released - I'm sure you appreciate that much depends on the progress of the first items to be produced. The MDAC2 design does not live in isolation, as we move forward experience is feedback into the design so its constantly being improved - until it finally meets the production line. I see the path as clear - DEVDAC and the Streamers, then the MDAC2 DD2A & Detox. So once you see the DEVDAC and the Streamers shipped, then you know MDAC2 DD2A is next.

One thing I am noticing, and please correct me if I am wrong, is that you seem to be developing and shaping everything around the streamer, as oppose to the streamer be just a 'optional' component of the DAC.

This has very much been a constant bug bare of yours - and I think everyone else can also see this. Considering the "Streamer" as simply a streamer is a very narrow view of the hardware used that also happens to handle the streaming function.

The CM3 module is used to implement the "brains" of the advanced DACs - driving the UI / displays etc. The CM3 interfaced to our Audio co-processing system is an integral part of the more advance designs where we use the CM3 CPU's processing power (discreet DAC and DD2A) - with these designs we also so happen to leverage the Linux environment to implement streaming services.

But stressing once again its not simply about streaming services as for me they have no relevance, but it should be considered more as a media player so one can replay directly from internal memory requiring no network or wireless connections, no external connected device - this is how I'll use my DAC most of the time.

The reason we use the CM3 and not simply the cheaper RPI solution is so that we can optimise the "Linux hardware" for audio applications with careful design to insure all clocks and switching PSU's are synchronised to the Audio master clock, without these design details it would be no different from just a separate Linux PC connected to a DAC with all the EMC and noise issues this entails.

Many of the lessons learnt from the Detox R&D are incorporated into the "streamer" solution. A great part of the "streamer" design's complexity is managing these clock domains, PSU's and interface noise. I'm personally unaware of any other Audio hardware (asides from our own pending designs) that goes to these lengths.

In a world where we cannot escape less physical media we need to engineer "Audiophile" solutions otherwise its over for our small world... I'm not interested in streaming services - this is a secondary function, but a self contained media player is interesting so long as it does not loose sight that we are a HiFi product not a computer.
 
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John, Can the DevDAC be used as a standalone DAC with USB and S/PDIF inputs?

Yes, *but it still requires the steamer board for system control.

*We could design a standalone front panel later (fitted alongside the secondary XMOS USB port).

There is ONE issue with the USB port in that it is shared with the Streamer Audio Coprocessor, so when the Streamer is selected the external USB device is automatically disconnected... - switching back to the "external" USB input and the external device has to re-enumerate...

We have a solution to add a second XMOS = a true second USB port as a user installable upgrade in the future (when time allows) - this will also support a PMD200 (HDCD) option. This secondary XMOS board plugs into existing connector headers on the DEVDAC PCB and can be fitted by the users as soon as its available (No soldering, just Plug & Play).

Also, we plan an optional ADC board for the DEVDAC / Streamer...
 
John,

As mentioned previously I am also interested in a devdac + streamer for testing/debug

Ok Noted, thank you - I'll reserve a PCB set for you.

I've not been following the thread over the past month or so (no time).

What exactly is the MDAC2 DDA ?.

I recall there were 3 MDAC2 variants ;
- descrete DAC or ESS9028 - interchangable daughter board for the DAC but same mainboard.
- ESS9038 full monty - not same mainboard as the other two options.

Is there now a fourth variant (aka DD2A)?

The DD2A is the x4 ES9038PRO design (So "only" 3 MDAC2 variants).
 
PCB's reserved for the "Developers addition" DEVDAC & Streamer from the first production batch to be shipped in the next 30 days:-

Rune
Hluga
Stephen Grenfell

Misterdog - did you want a set?
 
The MDAC2 DD2A will be the first "MDAC2" upgrade design to be released - I'm sure you appreciate that much depends on the progress of the first items to be produced. The MDAC2 design does not live in isolation, as we move forward experience is feedback into the design so its constantly being improved - until it finally meets the production line. I see the path as clear - DEVDAC and the Streamers, then the MDAC2 DD2A & Detox. So once you see the DEVDAC and the Streamers shipped, then you know MDAC2 DD2A is next.

Wasn't Detox ready for production? Why the delay? Was it not the plan to do Detox asap? When has that changed, this is the first time I read MDAC2 is produced first?

Not that I have anything against MDAC2 getting into production :p
 
Wasn't Detox ready for production? Why the delay? Was it not the plan to do Detox asap? When has that changed, this is the first time I read MDAC2 is produced first?

Not that I have anything against MDAC2 getting into production :p

Logistics of chassis production (Working with China) - I have to control funds, for the chassis I need a trip to China to QC that batch and that's US$5K +.... and then the time. There's also the same issue of upfront cost of complete reeled stock - this will become less of an issue as other designs are shipped and we have more reels loaded (paid for ) on the machine.
 
I bet you say that to all the girls.

I say many things to the "Girls" in the lab - like "is that really your stick", "who wants to do pee pee outside" and "stop barking - I'm trying to use the phone"... but I digress...
 
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Martin,

The MDAC2 is available in 3 variants - the streamer is compatible with all 3.

The streamer is an OPTION on the basic MDAC2 (Dual ESS9028PRO) and is required for the MDAC2 Discrete & MDAC2 DD2A


Like many here I started of with the original MDAC2 upgrade which then morphed into the FDAC and now back to the MDAC2. I am also in for a DETOX which now seems to have dropped off the cliff never to be seen again?

So now there are 3 variants of the MDAC2 to choose from. As somebody who has a Squeezebox and Vortexbox based system I do not need a streamer so if I want to go for a MDAC2 at this stage only the basic version is open to me if I do not want to pay for a streamer that I do not need.

The question for me and I am sure for others, is what are the pros and cons of these three variants and more importantly, for me anyway, is/will there be any significant audio quality difference between them? I am sure that there is wealth of technical spec that may lead one to believe that one particular variant will/should be better but the reality is it is what it actually sounds like in a real world listening test? Has this been done or will it be done before we have to commit to which variant we want to buy?

If I choose to go for the basic MDAC2 will it provide a significant improvement in audio quality over my existing MDAC? Will there be listening tests undertaken and reported back to the forum prior to us having to commit?

My understanding is that the basic MDAC2 will also require an additional add on power supply, though I assume that it will operate with the original supplied MDAC wall wart? Again, the question is has this been demonstrated with listening tests to confirm that the addition of the proposed separate power supply does indeed provide significant audio improvements?
 
To help with queries like the above, below is some compiled info on the 3 MDAC2 versions.

Requires external HQ PSU:
#1 MDAC2 Standard (Dual ES9028Pro)
#2 MDAC2 Discrete (shares the same mainboard as the MDAC2 standard), requires Streamer pcb, best DAC (but some drawbacks like no optical)

Uses old MDAC PSU:
#3 MDAC2 DDA (Quad ESS9038Pro's), requires Streamer pcb, best analogue stage, first to production

If I've missed anything, please copy and correct or add detail.
 
Sprint, they are all fair questions I reckon, especially the point about how the new DAC's will perform. One mans superb is another mans rubbish and always will be .

As for the comparison you'd like to know about re. how it will compare to the MDAC I'd assume it would have to be better or the whole thing is pointless.

I loved the MDAC I owned and it was a step up in terms of SQ from the previous DACs I had from years ago.

However just a simple RPI with an IQ dac or Allo sitting on top beats it hands down for SQ in both terms of depth of sound and clarity. The comparisons were made with other PFM guys present and level matched and blind, with the MDAC being recently recapped and in top fettle.

The RPI does the streaming job too with aplomb, especially for less than the price of a decent meal out.

So, if you can get proper SQ for this sort of daft money I think thing must have move on in the last few years.
 
The other advantage to the Streamer built in is the clock locking. The Squeezebox won’t have this advantage afaik...also this new Streamer will be more capable :)
 
A trip down the memory lane... For those who don't remember how things were before last christmas:
http://pinkfishmedia.net/forum/threads/mdac-first-listen-part-00110100.196475/page-7#post-3001585
(quoted below)
JohnW said:
MDAC2 Stage 1:-

https://dl.dropboxusercontent.com/u/86116171/mdac2 stage 1.JPG

The power connector has been replaced with a 15W D-SUB for higher current and parallel contacts. This also makes it easer for DIY PSU's.

Pair of 12V trigger outputs

Balanced Headphone XLR output

RCA SPDIF inputs have been replaced with BNC

Holes on rear panel for Non installed "options" covered with labels which can be removed when installing future options.

MDAC2 Stage 2 (RPi CM3 module installed).

https://dl.dropboxusercontent.com/u/86116171/mdac2 stage 2 RPiCM3.JPG

MDAC2 Stage 3 (ADC PCB installed):-

https://dl.dropboxusercontent.com/u/86116171/mdac2 stage 3 ADC.JPG

MDAC2 Stage 4 (FDAC "Slave")

https://dl.dropboxusercontent.com/u/86116171/mdac2 stage 4 Slave input.JPG

MDAC2 with all options installed:-

https://dl.dropboxusercontent.com/u/86116171/MDAC2 stage 1 to 4 RPiCM3 ADC Slave.JPG

To insure A Munch delivery date, the MDAC2 will be released as Stage 1, with the other options (RPI CM3, ADC & FDAC Slave interface) user installable as they are developed and available.
 
As somebody who has a Squeezebox and Vortexbox based system I do not need a streamer so if I want to go for a MDAC2 at this stage only the basic version is open to me if I do not want to pay for a streamer that I do not need.
The MDAC2 option #2 or #3 which requires the "streamer" board (is also the brain of the DAC and make it possible to control the DACs functions from a browser) does not prevent you from using your Squeezebox and Vortexbox.

You can just ignore the Streamer function and connect your Squeezebox to one of the Inputs.

You will get better SQ by user the Streamer as a Squeezebox and still run LMS on your Vortexbox.

I will try installing Squeezelite when I get "Developer edition" of the DevDAC and Streamer as well as RoonBridge. Might also try libSpotify which is spotify connect.
 
JohnW,

Just in case you missed it, I sent you an email asking to be included in the development kit order. Lets see what this streamer and devdac can do.

Cheers!.
 
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