Midiman Super Dac

Both of the DAC psus I have built have used die-cast aluminium boxes.

 

Saw these Encapsulated Toroidals at RS Components.


Are they quiter or better in some other way?

Since UK mains plugs have a fuse, is it necessary to fit a fuse in the box also?
Has anyone parallelled the two secondaries to double output current carrying capacity?

Thanks.

 

Potted TX's are meant to be quieter, in practice, not always.
Yes a fuse in the box would be required, the plug fuse will protect the cable, internal fuse will protect the equipment.
Cant remember exactly, but i dont think parallelling secondaries will double current capacity.

 

The easiest way to fuse the box is to use an IEC inlet with a fuse holder.

 

Speaking from experiance here, Both Iaasc and myself, I would fuse the input mains a/c and the output as well, 1a should suffice its well worth it and not too expensive to do, those of you feeling more flush could use one of those trick MSB's

 

IEC inlet with a fuse holder sounds like a good idea. Don't remember where but I have seen IEC inlet plugs with a built in switch also.

Somehow I don't like connectors, switches, fuses, neons, etc. Prefer a direct connection. But got have these I guess for safety reasons.

Tony, what are MSBs? RCD type thingy?

 

Yes, the output can benefit from fusing. A T 500mA L fuse might do on the output, as the superdac is rated to a max of 500mA. I certainly use 500mA on the 240V side, but in the case of the incident to which tone refers, it didn't blow (but the DAC chip and DIR did).

 

Magnetic circuit breakers, micro ones, you'll need fuses J, both myself and Iaasc had 'incidents' even though I already had one in the mains end, plus its always a saftey requirement

 

IEC inlet with switch and fuseholder:

RS Part no 2110979

I used one of these on my amp.

Michael.

 

Yup! That the one. Thanks Michael

May be a 'Flange Fixing' type is needed with cast metal box and not a 'Snap In' type?

 

How about soldering some varistors in parallel across the live and neutral terminals of the IEC plug?

When using metal box is it a good idea to earth it via the IEC plug?

 

BM
I would say that the wall thickness of a diecast box would mean you will need a flange fix type, they are also better fitting ime.
varistors wont do any harm, sure worth a shot, maybe some x class capacitors aswell, make a mini filter.
It is very important to earth the box, yep the IEC earth is what you should use. Any metal cased enclosure must be earthed, unless the high voltage side is double insulated.

 

Loads of these at RS under
All Products | Electronic | Capacitors | Mains Suppression Capacitors
Reading data sheets there and trying to get my head around them.
X catagory and not Y catagory should be good enough in this application, I guess.

Any suggestions as to which one?
X1, X2, X3, Delta X2, Voltage, value, how many?

Better still, any part numbers?

Thanks.

 

between live and neutral you want X1 or X2 class, around 0.01uf should do.
between live and earth you want Y class, around 0.002uf
values are aproximate, you could try different values in the ball park

 

Anyone got a schematic for this DAC please?
Or somewhere on the net?!

Thanks

 

I've not got a schematic, but it's pretty simple I think... I have actually been considering designing a simpler, no-compromise AK4395VF-based DAC. Would anyone be interested in buying a PCB? Costs.... I should be able to get PCBs done for £200 or so... not sure how many that would provide as I have to design it first. If there's enough interest I might do it. Total BOM cost off the top of my head would be about £200 for board, box, components, etc depending on component choices.

 

Ok, I've given this stupid idea it's own thread. I may yet regret this one...

 

18V PSU for Super DAC
Arne K aka caprigt2000, a member at Super DAC group, removed the diodes and fed the regulators with power from a new PSU: 2 x 18V, 120va trafo, a new diode-bridge, and 2 x 4700uF caps.

There is an very clear photo of his work in the photos section.

 

Anyone still into modding the Super Dac 2496?

Data sheets of these two in .pdf format are available to be downloaded in the files section of Super DAC User Group.
http://groups.yahoo.com/group/M-Audio_SuperDAC_2496/files/DataSheets/

CS8413 and CS8414 96kHz Audio Receiver Chip (38 pages)
AK4393 Multi-Bit 96kHz 24-Bit DAC (22 pages)

A parts list of (caps, regulators, ...) from anyone who have done internal mods will be appreciated by many modders at the group.

Thanks.