[Sapientiam]

Quote:

I measured all the resistors and think R2 is bad.  Anyone know the value for this one?  I measured 1 Mohm which I think means that its hosed.

No, that's correct for R2 - its part of the input biassing for the SPDIF receiver (which is just an HCMOS NAND gate - nice and simple). The HC00 gate in question is also fed from the same rails as the DIR9001 - I found I got a more symmetrical output from it by reducing R3. I've got 68k there now (was 100k).
 

 

[ptempel]

Ok, thanks for verifying.  I asked the seller for a schematic.  Will see if I get one.

 

[proid]

Hey guy, i just got this Muse Dac for 3 day and it sound incredible good, i dont have any dac for comparison but for the asking price, it's sure a bargain. Now i'm very interested in shorting this Muse. I'm now using a Kenwood R-SA7 amp which is a mini amp for a bookself speaker so i think it have coupling capacitor but i'm not sure and i don't have a DMM so should i just short the Muse and use some cheap 1$ headphone to test if it can be damaged?

 

[proid]

Quote:

Hi Guys! - new here so please don't flame me out, at least for my very first post...

 
I just got a Muse dac and have been modding it like crazy. If anyone's interested in the mods, I'll share them in due course.
 
Anyway the point of this post is - I may have found the reason so many Muse minis are dying prematurely. Mine has a 5V
regulator fitted where it should have a 3.3 volt one. That's in the power supply to the DIR9001 which does not like to get
more than 3.6V. When I removed the offending 5V regulator (right next to the input selector switch) the silk screen underneath
does indeed say it needs to be 3.3V. I have fitted an LM317L (220 / 330R) to give 3.1V and all is fine.
 
Bottom line is - if you have one of these its worth checking the markings on your AMS1117 reg and if it says 5.0 switch off
immediately!

Wow, great news, i always worry about Muse the life span of Muse Dac, just check mine, it has AMS1117 3.3V. And I'm interested in your modding too
But is there any way to know if the muse we ordered have AMS1117 3.3 or 5V?

 
 

 

[021311]

Has anybody tried applying thermal grease on d/a chips?

 

[fumbles]

Quote:

About the MD. If you set it on pause the disc is turning and standby for recording. IIRC the minidisc was magneto-optical. So no touching parts to wear out. But if it's your baby, treat it as such.

I allso have a Sharp portable MD, but I haven't used it in > 10y. It still works, only the battery is dead. It was one hell of a portable solution back then. Now it's only nostalgia; I only (ab)use my phone for portable use (yeah, you can slap me

).

 
I've used it a little but I'm wouldn't be comfortable running it 24/7. It works well though
 
I'm using a phone for my portable music these days too. Sounds good to my ears anyway.


Quote:

 
Anyway the point of this post is - I may have found the reason so many Muse minis are dying prematurely. Mine has a 5V
regulator fitted where it should have a 3.3 volt one. That's in the power supply to the DIR9001 which does not like to get
more than 3.6V. When I removed the offending 5V regulator (right next to the input selector switch) the silk screen underneath
does indeed say it needs to be 3.3V. I have fitted an LM317L (220 / 330R) to give 3.1V and all is fine.
 
Bottom line is - if you have one of these its worth checking the markings on your AMS1117 reg and if it says 5.0 switch off
immediately!

If mine has a 5v regulator when it arrives, will it run OK so long as I keep the voltage down to 9v? Or will it still die even at that? Should I just send it back if I find one there?
 

 

[proid]

I bought a cheap cable but i don't know how to mesure the dc output by a dmm. Some one can help me?

 

[Chefano]

Hi Proid, just set your multimeter to DC voltage. Connect the black tester point to ground of the ouput (external shiny part of the connector) and the red tester point to one of the internal connectors. If you are bypassing output caps shorting then, you should be able to mesure a value in Volts, if you are still using then an acceptable value is in the milli Volt range.
Quote:

I bought a cheap cable but i don't know how to mesure the dc output by a dmm. Some one can help me?

 

 

[Sapientiam]

 
Quote:

If mine has a 5v regulator when it arrives, will it run OK so long as I keep the voltage down to 9v? Or will it still die even at that? Should I just send it back if I find one there?
 

Keeping the input voltage down will have no effect. Mine ran for a couple of days OK before I discovered the problem - but who knows how much stress the DIR9001 has suffered in the process? It must've shortened its life. If you're not comfortable swapping out the reg its best to send it back yes.

 

[proid]

 
Quote:

Hi Proid, just set your multimeter to DC voltage. Connect the black tester point to ground of the ouput (external shiny part of the connector) and the red tester point to one of the internal connectors. If you are bypassing output caps shorting then, you should be able to mesure a value in Volts, if you are still using then an acceptable value is in the milli Volt range.


 

Hi Chefano, i don't know thich conector is the shiny one, i gues it was the yellow so i connect the black tester to the yellow connector and red tester to red or green connector. When i set 200mV, the Dmm displayed from 80-190 and it's not stable number. Then i switch to 2V and it's was stable at about 0.137 but how can it was that high? I didn't short the Muse and i have no problem with my headphone?
Edit: Now i use a 3.5 to 3.5 cable and mesure the tip sleeve and ring, the result now seem to be right, it's stable at about 135mV, and i mesured the headphone out of my onboard soundcard and it's 1.5mV. but i have run my headphone days by this setup with now problem. So should i just short the Muse and mesure if the DC offset <135mV,  it's ok?

 

[ptempel]

The seller got back to me but does not have a schematic.  Oh well.  If anyone here has one, then let me know.  I saw one floating around on diyaudio.com but the image resolution was terrible.

 

[021311]

I admit that I didn't do enough homework before purchasing this DAC,
but I just found out this is NOT a USB DAC, and my laptop doesn't have a coaxial nor optical ports.
What should I purchase in order to make this DAC work with USB 2.0?
I mean the seller put 50% of its price on shipping, so even if I returned it, I would only get half of my money back...
Thanks guys

 

[proid]

Quote:

I admit that I didn't do enough homework before purchasing this DAC,
but I just found out this is NOT a USB DAC, and my laptop doesn't have a coaxial nor optical ports.
What should I purchase in order to make this DAC work with USB 2.0?
I mean the seller put 50% of its price on shipping, so even if I returned it, I would only get half of my money back...
Thanks guys

You should by a Usb to Spdif converter, i suggest you to buy the Ha info U2

 

[021311]

Quote:

You should by a Usb to Spdif converter, i suggest you to buy the Ha info U2

Thanks for the quick response, what about driver for Win7? Will Turtle Beach Audio Advantage Micro II do the job?
 

 

[proid]

Quote:

Thanks for the quick response, what about driver for Win7? Will Turtle Beach Audio Advantage Micro II do the job?
 

It will work, but the aim of a USB - Spdif is to provide signal with quality, the HA info may quite hard to get then you should better buy some old cheap pci soundcard which have optical and coaxial like the creative soundblaster, it's cheaper then the Will Turtle Beach Audio Advantage Micro II and i think it will do the job better