Mutec MC-3+

[zoltan]

Yes, pictures, pleeease.

[zoltan]

So you totally removed the power supply unit? Or just soldered the cable to the posts? Did you measure the output voltage of the original power supply at the terminals?

[zoltan]

3 minutes ago, mecani said:

How do I loose the power supply?

screws, desoldering

Is there a benefit of removing the original as opposed to soldering the cable ends to the 'legs'?  

[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? 

[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. 

[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?

[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. 

[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.

[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. 

[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

[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

[zoltan]

31 minutes ago, mourip said:

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

 

 

Thank you, I will probably install two in parallel, that may be even better. 

I would like to ask you a favour of some sort. I would really like to know if the "LPS modded Mutec" sounds better with its original 6.3V or equally good with 5V. Some people reported that it works fine with Uptone's LPS-1 at 5V but they had no chance to compare to higher voltages. I guess most people would be scared to try 7V which is the next step on LPS-1. 

 

You could lower the voltage to 5 V and see if it is any compromise. I think that would be a very valuable contribution to this thread 

[zoltan]

13 minutes ago, nbpf said:

If I am not mistaken, in most of the posts in this thread the MC3+ USB has been deployed as a USB convertor and reclocker. Has anybody tried to use it as a reclocker of a SPDIF stream? I was thinking of trying it connected to the SPDIF output of an Allo DigiOne. Can I expect significant improvements or just differences? Thanks, nbpf

As well as the USB input, I use the spdif input to reclock my Oppo-UDP-203 for movies and concert videos. The result is the same as on the USB input, i.e. quite a nice improvement and I'm happy that the MC3+USB works as a multifunction unit for me. 

[zoltan]

On this topic of spdif input, I'm wondering how people connect devices like the Oppo or other transports. They only have RCA output and the MUTEC has BNC input. I have DIY-d a 75ohm digital cable which has the respective connectors at each end. This sound better to me than the same cable RCA-RCA and an RCA/BNC adapter, especially that most of those you can find are 50ohm and not 75. 
Has anybody else experimented with this? How do you connect an RCA ouput on transports to the MUTEC? 

[zoltan]

2 hours ago, nbpf said:

I cannot help here but, as a side remark: the Mutec also has an optical input if I am not mistaken. Given that the SPDIF output of the 203 is anyway limited to 24/48 because of copyright restrictions, you could also try an optical connection between 203 and Mutec.

Said who? A quote from the specs: "Output - Coaxial/Optical Audio: up to 2ch/192kHz PCM, Dolby Digital, DTS."

And it works. I streamed high-res files from my NAS with the Oppo while my SOtM SMS-200 Ultra was away for upgrades. 

During this time, I also tried two different optical cables, both real glass, and they were not nearly as good as the coaxial link. 

[zoltan]

On the topic of replacing the Meanwell PSU with a LPS unit in the MC3+ USB, I was wondering if everybody has soldered the DC cable to the posts and then going straight to the external LPS unit whatever that may be?

I'm thinking of converting my unit soon but thinking of installing some sort of DC-in socket in place of the IEC input so that I can connect different lengths of DC cables if it becomes necessary and also can experiment with different DC cables.   

Has anyone done it that way?

[zoltan]

21 minutes ago, Kritpoon said:

 

 I tried to remove the main board, but I cannot remove XLR connector release lever at the back (I dont have the specific tools that does that). 

 

1

You don't need specific tools really. Watch this video. (The beginning is rather annoying but after that it shows you how to do it.)

 

[zoltan]

1 hour ago, SwissBear said:

 

• it is mandatory not to exceed 6V (extreme max is 6.2V). Unless, the circuits of the MC-3+ USB which are not protected, could be damaged

 

One reason that holds me back from doing the mod is that this voltage thing has not been fully clarified. I remember reading that several people tested and the actual voltage from the original SMPS is 6.2-6.3V. It works with 5V but is it optimal?? 

I'm planning to supply it with 7V and internally (before reaching the board itself) burn off 1V as heat. I have a technician around who said that such a component can be installed together with a small heatsink in the space that is available after removing the SMPS. 

The SOtM SMS-200 apparently works better (SQ) at 12V than lower voltages. Might be the same for the Mutec unit.

I wish somebody compared 5V vs. 6.2V using the same LPS. 

[zoltan]

I would like to put a capacitor at the entry point of DC  (while converting to linear power supply). 

I have good quality Auricaps around like these https://www.soundlabsgroup.com.au/p/AU-0U47-400-10/0.47uF+400V+Auricap

 Should I connect the red or the black lead to the + terminal? 

 

[zoltan]

3 minutes ago, One and a half said:

I know the first two players can upsample to the MC-3+USB maximum capability, but OSX is limted to DSD128 over DoP. Other than that, feel free. I didn't like upsampling on the software players with the MC-3+USB, didn't sound all that good long term. So left the files to play as is.

I think it largely depends on what DAC follows the MC-3+USB. My DAC sounds best if it is fed with 192kHz signals, so I upsample redbook CDs in HQPlayer. I guess experimentation is advisable. 

[zoltan]

5 minutes ago, nbpf said:

Correct. There is only one USB port in the rear of the Mutec and it is an input port. Check https://www.mutec-net.com/downloads/manuals/MUTEC_MC-3plusUSB_Manual_E_screen.pdf page 13.

I don"t think so.

From the manual: "»USB I/O« This USB (Universal Serial Bus) interface receives or sends data streams in compliance with USB2.0."

[zoltan]

3 hours ago, 6aardvark9 said:

 

Indeed, the manual does not describe it because it is not possible, conversion via the USB port is one way only (USB > SPDIF)

I still disagree. They would not indicate I/O USB if it wasn't. Look at this article (from Mutec's homepage BTW) and see how the USB output function is used.  

https://www.mutec-net.com/artikel.php?id=1461772015

[zoltan]

12 minutes ago, beessy said:

For now, usb (O)utput is only for firmware update

Seriously guys/girls, please read the article that I linked a few minutes ago. It clearly states "Analog source simultaneously recorded as a Wave file with Sony Soundforge DAW application" but enough if you look at the photo

[zoltan]

16 hours ago, GregCA said:

The marketing material I read says the MC-3+USB is bi-directional.  Does that mean an ADC can be hooked up to the AES input, and the USB selected as an output to stream the digital to your computer for needle drops?   

 

Thanks in advance to anyone who had tried this and can confirm it works.

This was discussed a page ago. The answer is: yes. https://www.mutec-net.com/artikel.php?id=1461772015 

[zoltan]

4 hours ago, One and a half said:

 

Can't answer the first part of the question, but the MC-3+USB all native DSD is converted to PCM internally. As for DoP, it might just work, your DAC needs to accept DoP on say AES3 or RCA S/PDIF.

Then again, DoP might be come unglued when the stream is re-clocked and can't find the right frame.

I think DoP/DSD is also converted to PCM if it is fed through USB. Am I wrong? As far as I know, DSD put through is possible on s/pdif and AES/EBU inputs. 

 

As for Alvantri's question. I think the manual that you quoted from is for the previous firmware. The dealer's demo piece I had for a few days followed that illumination pattern but mine with the latest firmware is different as you described.