Basically: Fusion is discrete; Superior is opamp based?
MDAC First Listen (part 00110000)
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Basically: Fusion is discrete; Superior is opamp based?
JohnW
pfm member
Well both Fusion and Superior have discrete output stages - but the gain stage on the Fusion is discrete, and opamp based on the Superior BUT a completely different mode of circuit operation.
The FDAC / Superior have far greater RF attention, lower output impedance, lower THD and greater dynamic range.
The MDAC/ Toy / Fusion uses a Bipolar (transistor) output stage with about 25mA Class A Bias, while the Superior has a MOSFET based discrete output stage at about 60mA ClassA bias. The native output impedance of the Superior is over x10000 lower then the standard MDAC/TOY/Fusion.
JohnW
pfm member
Sadly no, its modification is just to involved - and requires testing once installed.
The MDAC's analogue stage has to be removed (lots of SMD components etc)....
JohnW
pfm member
There is a reference grade DAC - the FDAC, this is a completed new design and later there will be complete replacement board for the MDAC complete with new PSU.
MDAC2 resurfaces....
JohnW
pfm member
In a way, but its very evident that the MDAC PSU is a serious weak link which I don't have a solution for ATM.
The MDAC's rather limited PSU is a real problem that I cannot see a practical / cost effective solution to.
A Grommet and flying cables could be fitted in place of the MDAC's 8W MiniDin, not pretty but better then the low current MiniDin lead - but the external PSU poses problems, not least the cost of chassis & safety certification.
Before everybody cries wolf, I think a product roadmap is required ;-)
Here is what I understand:
We have 3 *DAC products on the horizon:
- the Superior 'add-on' board for existing MDAC to be available in the next few months (?), also to be sold as a complete solution with refurbished MDACs
- the reference FDAC (and its variants) by/around year end
-a complete replacement board for the MDAC, complete with a new PSU
The Detox is a related but separate product (which will be compatible with all the above and should be available in a few months)
There are also two families of mono amps (VFETs with analogue or digital input boards to be available after the FDAC, and upgraded Audiolab M8200s which should come on stream sooner, as John needs space in his basement ;-))
A pretty full product range but with a logic behind the madness!
That's a
Here is what I understand:
We have 3 *DAC products on the horizon:
- the Superior 'add-on' board for existing MDAC to be available in the next few months (?), also to be sold as a complete solution with refurbished MDACs
- the reference FDAC (and its variants) by/around year end
-a complete replacement board for the MDAC, complete with a new PSU
The Detox is a related but separate product (which will be compatible with all the above and should be available in a few months)
There are also two families of mono amps (VFETs with analogue or digital input boards to be available after the FDAC, and upgraded Audiolab M8200s which should come on stream sooner, as John needs space in his basement ;-))
A pretty full product range but with a logic behind the madness!
That's a
JohnW
pfm member
Yes correct, but we can also update "Your" own MDAC's with the Superior 'add-on' board.
We will build limited batch's of Superior 'add-on' board at a time, then by prior arrangement MDAC's can be forwarded for upgrade once the boards are ready and waiting
I really recommend the Superior 'add-on' board for those who already have the Calex PSU's as together they make a stunning combination.
iansr
pfm Member
Yes this is tricky. MCRU make a rather expensive external PS for the MDAC that certainly improves things but my suspicion is that one of the main reasons the 5 rail Calex makes such a significant difference is because it bypasses the MDAC's power input board. That presents certain practical difficulties - I've been running mine without the case but that is obviously unsatisfactory in the long term.
( I know what Paul is going to say in response
)
adamdea
You are not a sound quality evaluation device
I have no idea where you get this from . The Regen should have been complete and delivered a couple of months ago. The design was finished in February IIRC and it was pronounced an enormous success.
The F-dac should be entering production within a couple of months. No one has said otherwise.
Products currently in production= 0
In terms of this project "ready by the end of the year" is tradtionally announced around the time the October deadline has been passed, about two months before the "around April" announcement.
adamdea
You are not a sound quality evaluation device
Let me make this less negative: If the issue with getting the F-dac complete is funding I would rather have an additional call of £100 or whatever each and a firm schedule for delivery rather than a further distraction. I would be happy to stump up for a definite complete product which is actually going to be delivered.
JohnW
pfm member
Adam,
The Superior PCB is a development step towards the FDAC, the results of this board is feedback to the FDAC (optimisation of Bulk foils locations / capacitors etc). It also is our fist listen to FDAC circuit technology - even if in a rather restricted form, but its nice to confirm we are heading in the correct direction (sonically).
Until late October I have a couple of PHD students who will be avaible to upgrade MDAC's with the boards if there is any interest. I'll build the first couple of boards as testing and optimization its relevant to the FDAC - but then the students take over - I'll just listen and QC each unit before they are returned to the owner.
I need the results of the superior board to complete / optimise the FDAC Analogue PCB.
Yes - Detox needs to be progressed - maybe tomorrow I'll populate the redesigned sections on the production PCB to be able to confirm the BOM.
adamdea
You are not a sound quality evaluation device
Thanks John,
I've got nothing against the upgrade. I might even want my MDac done if I have a chance. I'm just keen to get my hands on the statement only-adc/dac-I'll-ever-need. That and a decent pair of speakers for my study may well be me and hifi over.
fusion5
on the dark side of hifi...
I'll ship the MDAC on Monday. It should arrive within 3 or 4 days.
As I recall you wrote it would be a quick step, are you still planning on creating a simple board to be able to close the MDAC case and power it with 3 Calex PSUs (leaving owners of such solution with the need to find a suitable housing and connector to plug into the back of the MDAC)?
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