[danieldpagan]

Had mine for several months now and Im still amazed with the sound. Hopefully though they come out with a version that has a balanced hp output.

 

[bilzebub]

Have had (1st version) Mini-I for a number of years, and worked well with Win 7 machines. However, after upgrading these to Win 10 I have had nothing but problems (USB connection). On one laptop the sound cuts out after 15 min but works when plugged and unplugged. On another loud static plays randomly for 3-15 seconds at a time before resuming playing normally. I cannot install either 1.67 driver or 2.24, and not sure if these would work with original unit anyhow, but these are the only ones available on the Martrix website. The units have been using a native Windows USB sound driver from circa 2010. Has anyone else had this issure or found a workaround? Thanks

 

[pwrusr]

I recently had to decommission my Mini-i.
It kept powering down by itself.
needed to literally pick it up a inch and drop it to get it back on again. 
 
Popped the hood and discovered that several capacitors had popped. I'm now in the market for a new DAC
 
On the plus side, it did last me a good 5 years before it started this issue.

 

[ArthurPower]

Matrix has a new Mini-i driver (3.40) for anyone who has experienced issues with Windows 10 after installing the Microsoft Anniversary Update.
 
You can download it here from our site. Anyone with the Anniversary Update please report your findings. This should fix any problems some have experienced.

 

[penmarker]

  Matrix has a new Mini-i driver (3.40) for anyone who has experienced issues with Windows 10 after installing the Microsoft Anniversary Update.
 
You can download it here from our site. Anyone with the Anniversary Update please report your findings. This should fix any problems some have experienced.

My web filter was triggered because of the .exe file. Maybe you can put it in a .zip file for those who are affected.
 
Also, while you're here, my Mini-I has a semi defective display. The intensity of the display is not uniform as some patches of lights are dimmer while some are brighter. Do you do repairs and any idea why its happening? It works fine though.

 

[ArthurPower]

I just updated the link in my post above to point to a zip file. Apparently head-fi reformats the url to a redirect, that might of been the problem you were having.
 
Regarding the display issue please use the contact form on our website so I can try to help you with that.

 

[APrender]

I've had a Matrix Mini-I v.1.82 for a couple of years, and I've been really happy with it, but...

... a while ago, a weird problem with the display appeared. Upon power up the display worked ok, but after a while it showed just gibberish. Took the thing apart, and some of the electrolytic capacitors had swollen, though not leaked.

Now the unit won't react at all. When I flip the power switch, nothing. If I press the volume knob, still nothing. I have already replaced the faulty caps to no avail.

I'm looking for some good advice on where to start looking for the problem. Can anyone help?

 

[penmarker]

I've had a Matrix Mini-I v.1.82 for a couple of years, and I've been really happy with it, but...

... a while ago, a weird problem with the display appeared. Upon power up the display worked ok, but after a while it showed just gibberish. Took the thing apart, and some of the electrolytic capacitors had swollen, though not leaked.

Now the unit won't react at all. When I flip the power switch, nothing. If I press the volume knob, still nothing. I have already replaced the faulty caps to no avail.

I'm looking for some good advice on where to start looking for the problem. Can anyone help?

Have you checked if the fuse is still intact?

 

[APrender]

Have you checked if the fuse is still intact?

Yes, the fuse is ok.

 

[penmarker]

Huh. That's a tough one. Sorry can't help much.

 

[APrender]

Huh. That's a tough one. Sorry can't help much.

Thanks anyway. I should have told the fuse was ok in the first place.

I measured the +12V and -12V voltage regulators near the transformer (unit powered on). I didn't get a good reading, just a few hundred millivolts, and somewhat fluctuating. I'm going to double-check them later today with a better multimeter. Could the transformer be dead? Sounds unlikely to me.

It would be helpful to know what kind of voltages to look for at different places on the PCB, and how to check if the power supply components are ok.

 

[APrender]

I measured the regulators, and the +12V reg shows 0.138V at input and 0.080V at output. The -12V reg shows -0.361V at input and 0.193V at output. Not good.

Interestingly, the two +5V regs near the display have 12.00V at their inputs and 4.992V and 4.999V at their outputs, so at least they work. The third +5V reg near the flat display cable has 0.366V at input and 0.000V at output.

I even pulled the transformer from the PCB but as it is a sealed unit, there wasn't much I could do. Primary and secondary resistances seemed reasonable, that's all I can say.

What could be the culprit? I'm running out of ideas.

 

[penmarker]

Well, maybe the regulators are faulty? Try and replace the regulators. Are there markings or anything on them?

 

[APrender]

Well, maybe the regulators are faulty? Try and replace the regulators. Are there markings or anything on them?

That's exactly what I did. The +12V and -12V regulators were standard L7812CV and L7912CV which I luckily had in my stock from another project. Those weren't necessarily faulty, however. It seems they don't get input unless the whole unit powers on. The +-18V from the transformer is routed to the regulators through a relay near the TRS jack. Probably a power saving feature.

The +5V regulator is a 78M05, an SMD part, which I don't have in stock. However, I replaced it with a LM7805CV. The SMD part can dissipate heat to the PCB, so I added a heatsink to the LM7805CV just to be safe. It ran quite hot without it.

Now the Mini-I powers on, but the display is still a mess.

 

[penmarker]

Does it run well despite the mess? Mine works ok but the screen is a little messy as well. Some pixels are bright while others are dim.

Now I'm a little worried if my unit will go faulty too.