Mutec MC-3+

[zoltan]

15 hours ago, SwissBear said:

According to Mutec, leaving the stock SPSU in place could cause the 2nd stage of this SPSU to remain active and cause interference. So you need to remove it...

Can you please tell me how much desoldering is needed? Is it only the two legs that go down from the SPSU or some other place, too? 

[afrancois]

4 legs need desoldering. 2 for AC and 2 for DC. Built-in power supply rests on 4 legs.

[zoltan]

17 minutes ago, afrancois said:

4 legs need desoldering. 2 for AC and 2 for DC. Built-in power supply rests on 4 legs.

Thank you. But I can see in the photos that only the front two connectors are used as DC input. I guess that was the DC output for the SPSU. 
To desolder, did you remove the baseboard and desoldered from the bottom, or it can be done from above? Sorry to ask so many questions but would be good to get advice from somebody who has done it. 

[afrancois]

Desoldering needs to be done underneath. So you will have to remove the motherboard.

[afrancois]

After some serious listening sessions, I can conclude that the power supply upgrade with the LPS-1 was worth the hassle!

 

If you have the technical skill or you know someone who can do it for you, this upgrade is highly recommended.

[mecani]

Hola

 

 Él reemplazó la fuente de alimentación del mutex mc3 + por un peluche marrón

 

[zoltan]

A question to those who also use the BNC 75 ohm input connection. I have an OPPO UDP-203 which only has RCA output. I use a high-quality Acoustic Revive digital cable to the MC3+USB but I have to use an RCA-BNC adapter at that end. Unfortunately, the adapter itself is also a 50 Ohm adapter that I only noticed recently (until a few weeks ago I could not tell the difference). I guess this is not ideal.

Options are 

1. source a high-quality adapter - Van den Hul has them... but to order one piece??

2. replace the RCA connector at the end of the AR digital cable with a BNC connector - and lose the resale option of the cable

3. make a DIY cable with different connectors at each end 

 

How do other people connect such players?

[SwissBear]

2 hours ago, zoltan said:

A question to those who also use the BNC 75 ohm input connection. I have an OPPO UDP-203 which only has RCA output. I use a high-quality Acoustic Revive digital cable to the MC3+USB but I have to use an RCA-BNC adapter at that end. Unfortunately, the adapter itself is also a 50 Ohm adapter that I only noticed recently (until a few weeks ago I could not tell the difference). I guess this is not ideal.

Options are 

1. source a high-quality adapter - Van den Hul has them... but to order one piece??

2. replace the RCA connector at the end of the AR digital cable with a BNC connector - and lose the resale option of the cable

3. make a DIY cable with different connectors at each end 

 

How do other people connect such players?

 

Why not source a cable with an RCA connector on one side and a BNC on the other. Not necessary an expensive one: https://www.thecableco.com/Product/S-Link

[zoltan]

1 hour ago, SwissBear said:

 

Why not source a cable with an RCA connector on one side and a BNC on the other. Not necessary an expensive one: https://www.thecableco.com/Product/S-Link

That is an option but I have a few metres of good quality 75Ohm cables around and both BNC and RCA connectors so I can make these myself. I thought that before getting down to it, I'd ask how other people manage this 'issue' and perhaps have done some comparisons of using an adapter or going RCA-BNC straight. 

[Kritpoon]

On 9/16/2017 at 2:45 AM, afrancois said:

I just finished modding my MC3+ USB. It is now powered by an LPS-1 at 5V.

 

Be prepared to hear every defect in the recording! I'm hearing tape hiss I've never heard before.

 

Very revealing!

 

@afrancois with LPS-1 @5v to the MC-3+ usb, since its been a while after the conversion, as of now does your MC-3+ USB have any operations issue? Thank you.

[catcando]

I am due to receive a second Mutec MC3+USB, next week, and would like recommendations on the correct connections and settings, for daisy chaining.

I am currently using the AES input from my transport, and the USB input from my streamer, and the AES output, to my DAC.

Thanks for any help.

[SwissBear]

42 minutes ago, catcando said:

I am due to receive a second Mutec MC3+USB, next week, and would like recommendations on the correct connections and settings, for daisy chaining.

I am currently using the AES input from my transport, and the USB input from my streamer, and the AES output, to my DAC.

Thanks for any help.

You just need a short AES/EBU cable between the AES output of the first unit and the AES input of the second.

You will need to set the second unit on the AES/EBU input, as you are used to do when capturing the input from you transport.

[catcando]

So, transport into AES on first unit, USB input on first unit, AES output on first unit, to second unit AES in, and AES out, on second unit, to DAC??

[zoltan]

22 minutes ago, catcando said:

So, transport into AES on first unit, USB input on first unit, AES output on first unit, to second unit AES in, and AES out, on second unit, to DAC??

Yes.

[catcando]

Thanks

The settings stay the same, on the first unit, and the second unit, is set how??

Thanks for helping an old fart.

[afrancois]

22 hours ago, Kritpoon said:

 

@afrancois with LPS-1 @5v to the MC-3+ usb, since its been a while after the conversion, as of now does your MC-3+ USB have any operations issue? Thank you.

Still works fine. No problem. Today I also added the newly arrived BNC caps. This softens the sound a bit. I could however be imaging things.

[Kritpoon]

7 minutes ago, afrancois said:

Still works fine. No problem. Today I also added the newly arrived BNC caps. This softens the sound a bit. I could however be imaging things.

 

Thank you. Which BNC caps did you get? 

[afrancois]

7 minutes ago, Kritpoon said:

 

Thank you. Which BNC caps did you get? 

https://www.aliexpress.com/snapshot/0.html?spm=a2g0s.9042647.6.2.77RgXl&orderId=85958803345657&productId=32616587366

 

I just had to remove the center pins. They are simply screwed in.

[zoltan]

1 hour ago, catcando said:

Thanks

The settings stay the same, on the first unit, and the second unit, is set how??

Thanks for helping an old fart.

On the second unit, you'll always have the AES/EBU as input. The clock setting should be 'internal' and 're-clock' unless you have a Mutec Ref 10 or another 10MHz clock connected. 

[catcando]

Many thanks. Hopefully will report back next week, with good news.

[mourip]

Well I am a bit late to the game regarding exchanging the SMPS in my Mutec 3+ USB but I did so yesterday. Thanks to all for the tips and tricks!

 

Being lazy I decided to find a way to remove the SMPS without removing the motherboard and was successful. The SMPS is soldered to 4 pegs that are also conductors and have through-hole connections. I carefully applied heat to each successive pin while pulling upwards. After a couple rounds of this I had managed to un-solder and release all pins, freeing the board. Before starting I did decide that I had no intention of being able to reverse the mod however so I was not concerned about damaging the SMPS. Luckily it worked out very well.

I used one of the included cables for my HDPlex LPS by cutting of the DC connector and prepping the leads for soldering to the DC inlet pins that were now well exposed. As I had previously removed the USB board that I did not need with my Dante setup I used that opening to thread the cable in for soldering to the pins. Along with soldering the cable to the pins, being extremely careful to understand the polarity of my cable, I soldered one electrolytic capacitor across the DC leads(observe polarity) and paralleled it with a small value polypropylene cap. I did this to help compensate for the longish cable from the LPS. I used the variable output on my LPS and set it to 6.3 volts.

 

Did it help? The clarity in my system which was already very good was now remarkable. I can easily follow individual instrumental threads within complex music. Definitely worthwhile.

 

On a separate but related note. I have now added a Mutec REF10 to my system. Within a few days I will write that up and post in the REF10 thread.

[zoltan]

39 minutes ago, mourip said:

Well I am a bit late to the game regarding exchanging the SMPS in my Mutec 3+ USB but I did so yesterday. 

1

Well, you are still ahead of me in this game :-) I'm about to do it very soon. I guess we are not lucky enough that perhaps you documented the removal of the SMPS by photos...?  I know there are a few but out there but more is always helpful.

 

May I ask what capacitor you added and what value? Also, what power supply do you use that can provide 6.3V?

 

Thanks

[mourip]

I thought about photos but they would basically look the same as from others who have already posted when they removed the SMPS completely. 

 

Regarding the capacitor. Probably anything over 15v and 50mf would be fine. I think that mine was 25v and 680mf because I just had it handy. I would caution about using one that is too large in capacitance as it might trigger over-current protection when you turn on your LPS, assuming it has that protection. Otherwise I would vote for 50 to 1000mf. I put the cap in there sort of reflexively after building many power supplies for analog devices where there are often transient needs for power. I would image that the Mutec uses a pretty unvarying amount. Just a guess. Anyway the results were certainly good!

 

I use HDPlex LPSs which have 4 outputs, three fixed and the third variable. They are not cheap and some will say that others are better but they have been very reliable and the customer service is excellent.

 

Just a heads up. If you try to remove the SMPS in the way that I did you may damage tracings on it and not be able to put it back in. Also triple check the polarity of your cable when you install it. No sense letting the smoke out! Your warranty is of course toast whatever you do :-)

[zoltan]

35 minutes ago, mourip said:

Regarding the capacitor. Probably anything over 15v and 50mf would be fine. I think that mine was 25v and 680mf because I just had it handy. I would caution about using one that is too large in capacitance as it might trigger over-current protection when you turn on your LPS, assuming it has that protection. Otherwise I would vote for 50 to 1000mf. I put the cap in there sort of reflexively after building many power supplies for analog devices where there are often transient needs for power. I would image that the Mutec uses a pretty unvarying amount. Just a guess. Anyway the results were certainly good!I

5

I have a few auricap 0.47mfd /450V capacitors around from earlier projects. I wonder if they would do the job? They are low value but very highly acclaimed in the audio world, quite expensive, too. Would be good to use them somewhere.
https://www.audiohobby.eu/en/auricap-xo-600v/5558-capacitor-auricap-xo-047-uf-10-600v.html

[mourip]

1 minute ago, zoltan said:

I have a few auricap 0.47mfd /450V capacitors around from earlier projects. I wonder if they would do the job? They are low value but very highly acclaimed in the audio world, quite expensive, too. Would be good to use them somewhere.
https://www.audiohobby.eu/en/auricap-xo-600v/5558-capacitor-auricap-xo-047-uf-10-600v.html

 

I am sure they would be fine. My theory was that it might be good to have a somewhat larger "reservoir" of capacitance handy so I used the modest electrolytic in parallel with the poly cap.

 

Try the Auricap and see. It is about experimentation. It will probably be better than not using one at all.