MDAC first listen (part XXIV)

[Richard Kimber]

John:

I've been pondering my options, and don't want to delay things by insisting on the full fusion update now, but I'm a little confused about what's possible. I've ordered the fusion kit from hificollective. Are you able to do the Toy+ upgrade now using parts from this kit (when you get it), or would I need to order a separate Toy kit?

If you can do the Toy upgrade from the fusion kit and keep the rest of the resistors for the new pcb, and later do the at cost DIY upgrade, then perhaps that's the sensible option for me to choose.

Incidentally, would the Asian-sourced bulk foil resistors for the new pcb be the same quality as the Charcroft?

- Richard.

 

[Sonic_D]

Ok I see the MDAC2 appears to have taken over from the current upgrade. I was waiting for resistors to become available and shipped before sending my MDAC to JohnW for the L2 mod, but I shall now pledge my support for the MDAC2 pcb development instead. Wikki signed.

 

[jamjar784]

Yes I'm still hoping John will do the full Fusion and AV bypass for me once the resistors arrive. I'm sure the the sound quality will be plenty good enough for me for quite a while. I will consider the Mk2 when in full production but I won't be in a rush.

John,

I'm with IanM on this. You probably missed my post way back earlier, but I'd like to go ahead with the Fusion upgrade as I've already laid out the cash for L2+Fusion resistors. If I'd had the option to buy the resistor kit now I'd have gone for the L2 Toy+ as VFM and saves you and the PFM'ers time.

Sorry chaps

 

[jirij]

John,
if my back panel still doesn't have another hole, I'd like to wait with the balanced headphones option. It will save me some time resoldering the connectors, you should have less work as well, ... and I can live with unbalanced for the time being. Or with the dual 3pin XLRs on the back.

If you're still not 100% sure what connector to use for balanced headphones on MDAC2 (back panel?), I'd probably suggest the 4pin female XLR socket. It might not make much sense engineering-wise, but it's what people mostly use, I've seen it in at least 2 different DIY setups aside from those sennheiser amps. Aside from the crazy double-3pin, of course.

Thanks,
Jiri

edit: One more point for full size 4pin connector - Neutrik sells them ... miniXLR are a lot harder to come by, especially in a good quality.

 

[JohnW]

John,

I'm with IanM on this. You probably missed my post way back earlier, but I'd like to go ahead with the Fusion upgrade as I've already laid out the cash for L2+Fusion resistors. If I'd had the option to buy the resistor kit now I'd have gone for the L2 Toy+ as VFM and saves you and the PFM'ers time.

Sorry chaps

As I say no problem Your resistors can always be transferred to the MDAC2 PCB if you decide to upgrade, only you would have to return your unit to Czech Rep. for upgrade.

 

[JohnW]

Ok I see the MDAC2 appears to have taken over from the current upgrade. I was waiting for resistors to become available and shipped before sending my MDAC to JohnW for the L2 mod, but I shall now pledge my support for the MDAC2 pcb development instead. Wikki signed.

Thank you

 

[JohnW]

John:

I've been pondering my options, and don't want to delay things by insisting on the full fusion update now, but I'm a little confused about what's possible. I've ordered the fusion kit from hificollective. Are you able to do the Toy+ upgrade now using parts from this kit (when you get it), or would I need to order a separate Toy kit?

If you can do the Toy upgrade from the fusion kit and keep the rest of the resistors for the new pcb, and later do the at cost DIY upgrade, then perhaps that's the sensible option for me to choose.

Yes, the Fusion kit includes the x4 resistors required for the Toy+ upgrade, So I can upgrade your unit to Toy+ Spec. and keep the balance of Fusion resistors for your MDAC2 PCB - As its cheaper to order a replacement kit of toy resistors then shipping your unit back to Czech Rep. for upgrade to MDAC2 when the PCB is available.

You can then DIY Home swap your fully Fusion MDAC2 PCB (saves you being wthout your MDAC once again).

Incidentally, would the Asian-sourced bulk foil resistors for the new pcb be the same quality as the Charcroft?

I'm not even aware of a Asian sourced brand of Bulk Foil resistors - I trust very little that comes out of China - its REALLY hard work insuring quality from China unless you have a really good vendor - Our PCB and Organic Capacitor vendors are the few I trust.

 

[JohnW]

I added myself to the list on the wiki. Looking forward to see how things evolve with this MK2 venture!

Thank you

 

[JohnW]

Hi John,
I have the other "Multicom" resistors L2 MDAC, I've skipped a couple of days of this thread and I'm not sure I understand how things have evolved..
I wanted to send you my L2 MDAC and order the FUSION resistors from HiFiCollective today to swap the "incriminated" Multicoms, is it still a sensible thing to do? Consider that if there are further (PCB,dual dac?!?) enhancement options I'm in for them as well.
What do I have to do? I am at a loss concerning how to proceed with the resistors substitution and other further enhancements..

Its my Duty!!! to swap out those Multicomp resistors for you... Its my bad that they are even in your unit in the first instance - I have no problem to upgrade your unit to Toy+ spec. (Sorry I forgot to add you to the earlier list of units that are scheduled to be upgraded and are not stacked up behind me here in Czech).

Best wait for the AV bypass option until the MDAC2 PCB is released.

 

[JohnW]

1) Do I understand correctly that a "Toy" MDAC2 can later be updated to a "Fusion" MDAC2, and if so would this be a difficult/risky DIY job?

Yes its a resistor swap, however it involves removing SMD components and once the resistors are replaced with the Bulk Foils the Analogue stage needs to be adjusted - so the Resistors swap is not a simple DIY job.

2) Will the AV bypass be selectable via remote control?

Yes the MDAC2 PCB will be designed fromm the start to support AV bypass

3) At the moment I only switch to the MDAC for serious listeneing - my work horse is still the CDQ, soley due to the analogue pre and the fact that I have my turntable/phono stage plugged into it. I take it that the MDAC Mk2 won't be doing anything to change this situation?

You can route your Analogue sources via the AV bypass input - then using an analogue pre-amplifier you can adjust (and select) the level of the analogue sources such as your turntable etc.

4) Presumably the new PCB will still support both XLR and RCA output?

Oh Yes, same connector arrangement as the MDAC but with the extra AV bypass conectors.

 

[Clerenlas]

We will have to make a new rear panel - we already have our own tooling....

As we get closer to production, I'll need to know the colour of everyone's unit..

John

If you're making a new rear panel, accommodating the AV bypass, will it be home-fittable too, along with the new PCB? Or would we need to send the MDAC to you if we're having the bypass implemented?

 

[JohnW]

John, in the above case, does the owner send the original MDAC Toy+ PCB back to you after the DIY?

Leon

Hi Leon,

Depends if we can meet the GBP120 to GBP150 target cost of the MDAC2 PCB without resorting to cannibalising components from the original MDAC PCB. If we are over budget the we will need to remove the key expensive components such as the ESS DAC, Organic capacitors and RCA connectors etc. from the original MDAC PCB.

 

[JohnW]

John

If you're making a new rear panel, accommodating the AV bypass, will it be home-fittable too, along with the new PCB? Or would we need to send the MDAC to you if we're having the bypass implemented?

The MDAC2 PCB will be shipped with the new rear panel, allowing a quick and easy DIY swap - that's why I would need to know the colour of your unit before we ship your MDAC2 PCB to allow us to supply the correct colour rear panel.

AV bypass will be standard on the MDAC2 upgrade.

 

[JohnW]

Thanks. Any ideas when this endeavour to take us all to audiophile nirvana will start?

Also, are there any plans for an updated front plate.

I need to upgrade and ship the L2/Toy/Fusion units waiting for the Fusion / Toy resistor kits before we can officially launch the MDAC2 project (and request the first down payment)

No ATM the MDAC faceplate remains the same, maybe later we can offer a new front panel which can be retrofitted by the owner.

 

[JohnW]

John,

what's your final impression of the fusion upgrade?

I'll keep it as a surprise for you (looking forward to hear what you think ) - Lets just say Renata tried to kidnap your unit! last week I had to pry Joke721 unit from her then today yours! Its only because you wished Renata a happy Birthday last year and sent her chocolates that see agreed to let go of your unit!

 

[ddenyer]

Hi John,

any chance of a 12v trigger in MDAC-Next?

Cheers, Derek

 

[StephenB]

Hi John,

any chance of a 12v trigger in MDAC-Next?

Cheers, Derek

+1, my monos keep switching off when listening to V+ box unless I'm at -35db !!!

 

[iansr]

John,

As I'm not sure it makes sense for you to spend time adding the AV pass through and the Full fusion update to my MDAC if the M2DAC is 'just around the corner', I'd be willing to consider just a 'Toy+' upgrade for the time being.

The extra resistors Fusion resistors and AV pass through funds could stay with you until the M2DAC comes to life.

Me too John. I've already said divert my £50 for the bypass to the PCB but for now ill take the Toy plus upgrade and you just hang on to the remaining resistors until the PCB is ready.

 

[JohnW]

Hi John,

any chance of a 12v trigger in MDAC-Next?

Cheers, Derek

I'll look into it (Basically if I have time left) - otherwise I can design a dongle that attaches to the MDAC2 rear Communication Bus for 12V Triggers.

 

[dtd]

Out of interest, on the new MDAC2 PCB, does it upset the output circuitry if its more towards 2.5v/5.0v balanced RMS output level?