klipschman70
Active Member
Picked up my silver MDAC this morning from NA distributor and when I connected it to my system, I realized only one channel is working. Anybody experienced this before or do I have a bad unit ?
MDAC first listen (part V)
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travelfotografe
pfm Member
My first unit developed the same problem after a day of running in. Took it back to the dealer and it worked fine when they tested it. We suspect the physical movement of the unit unstuck the stuck relay. Maybe you can try giving your unit a few shakes.
My dealer kindly exchanged a new unit for me, even though the unit played correctly at the showroom when I took it back. The replacement unit has been working perfectly since for the past three months.
My dealer kindly exchanged a new unit for me, even though the unit played correctly at the showroom when I took it back. The replacement unit has been working perfectly since for the past three months.
klipschman70
Active Member
Thanks
I will give it a try tomorrow morning. Anyhow, which channel did not work in your case? mine is the right channel.
I will give it a try tomorrow morning. Anyhow, which channel did not work in your case? mine is the right channel.
travelfotografe
pfm Member
JohnW
pfm member
Hi klipschman70,
After you have had to wait for such a long time, I'm extremely sorry to hear of your issue.
It does sound like a case of a stuck Mute relay - you could try cycling the relays by inserting and withdrawing headphones.
I can only hope after your long wait that your dealer has a spare replacement unit.
klipschman70
Active Member
In the meantime I have tried to plug in and out headphone jack without any success. The other thing is, the MDAC seems to work properly both channel on headphone jack. However only one channel working from either RCA/ balance output.
When I used headphone jack with MDAC and stream 24/192k file from Oppo BDP-93. Only the first song title would play. On the second song, MDAC only showing 192.001k (the first song it showed 24bit /192.001k)
I've got an M-DAC winging its way to me later this week.
I'm primarily interested in using it as a high quality DAC and headphone amplifier with my laptop and HiFiMan HE-500, but I will also be trying it in my main rig where it will be up against my Young DAC / SQ-PSU.
I will also try using it in place of my pre-amp (Classé DR-6 MKII) to feed my Classé DR-10 power amplifier directly. (Although this is not a viable long term option as I have an analogue source too)
Pictures / report to follow
Lefty
I'm primarily interested in using it as a high quality DAC and headphone amplifier with my laptop and HiFiMan HE-500, but I will also be trying it in my main rig where it will be up against my Young DAC / SQ-PSU.
I will also try using it in place of my pre-amp (Classé DR-6 MKII) to feed my Classé DR-10 power amplifier directly. (Although this is not a viable long term option as I have an analogue source too)
Pictures / report to follow
Lefty
I've got an M-DAC winging its way to me later this week.
I'm primarily interested in using it as a high quality DAC and headphone amplifier with my laptop and HiFiMan HE-500, but I will also be trying it in my main rig where it will be up against my Young DAC / SQ-PSU.
I will also try using it in place of my pre-amp (Classé DR-6 MKII) to feed my Classé DR-10 power amplifier directly. (Although this is not a viable long term option as I have an analogue source too)
Pictures / report to follow
Lefty
The HE-500 sounds pretty good out the M-DAC but they won't reach their full potential. They need more current and voltage swing.
JohnW
pfm member
Hi klipschman70,
This clearly points to a faulty Mute relay on your Right channel (the Right Channel works though the headphones).
The Oppo BDP-93 issue has been report here before - We have no idea of the cause - however we can work with your directly with diagnostics software to resolve the issue - Pls. PM your Email address and Dominik will communicate with your directly to pinpoint and resolve the issue.
Sorry for your issues, the Oppo locking issue can be resolved with a software update - the however you will need the unit exchanged for the relay issue.
John
JohnW
pfm member
How much current and voltage swing do they need? The MDAC's Class A CROSS output stage is pretty beefy...
klipschman70
Active Member
John
Thanks for the clarification. Fortunately my NA distributor has a spare unit for me. I will exchange my faulty one with the new one tomorrow. Hopefully I don't have this issue with the new one.
BTW, I have sent you PM with my email address.
Regards
Harry
JohnW
pfm member
Hi Harry,
So do I!!!
I've forwarded your Email details to Dominik and he will work with you on resolving the Oppo locking issue.
John
Is it really good enough to replace something like a Classé DR-6 mkII as pre? Also, how are you incorporating your TT into such a setup?
As regards the headphone stage, the M-DAC will be going against a Fiio E7 (used solely as a USB DAC via the L7 module) which feeds a Lovely Cube Premium headphone amplifier. See here for a run down:
Lovely Cube Premium
Is the M-DAC likely to better this with the HE-500?
Lefty
I can't provide specific numbers but being a relatively hard to drive orthodynamic headphone I found they really scale up well with more powerful amp.
While I was surprised by how good the MDAC head. amp is , imaging and dynamics are noticeably better on my LD MKVI+, which is not probably a fair comparison as it is a balanced design that can produce clean amplitudes of 70Vp-p into 120 ohms (according to the manufacturer)
Never heard a Lovely Cube and there is no specs so impossible to compare to the MDAC.
therixonator
pfm Member
Hi John, I've got my M-Dac plugged into my 2 year old Sony Vaio and I'm using Foobar and Wasapi. I've followed the manual and changed all the settings as suggested. The buffer is set to 50ms. I still get drop outs every 40s or so just as PhilC posted many months ago. I've changed the laptop power output as you suggested to him, but I still get probs. It's a decent spec machine so I don't get why it is failing. I normally use Sonos and that has worked perfectly, I'm only using the laptop as I'm getting married in a couple of months so I need a portable non networked solution. I'm in the process of copying the music off the NAS to the local hardrive on the laptop, but I'm not confident of an improvement as the Sonos accesses it from there with no trouble. I do also own an rdac so I could see if the drop outs occur on that if it helps. By the way I changed the display to show the buffer level, it tends to wobble around 50%, then I hear a pop, and see the buffer drop to around 20%. Thanks, James
I think I may have asked this before but forget the answer, what are the specs for the headphone amp?
John reported:
"The Headphone outputs are the same quality as the Mainoutputs.
THD 0.0015%
SNR-A 117dB
Output impedance lessthen 1 Ohm
Output current limited to +/- 120mA (Before current limit starts to kickin)"
Which should be more than adequate for the vast majority of headphones
"The Headphone outputs are the same quality as the Mainoutputs.
THD 0.0015%
SNR-A 117dB
Output impedance lessthen 1 Ohm
Output current limited to +/- 120mA (Before current limit starts to kickin)"
Which should be more than adequate for the vast majority of headphones
Ok, my knowledge with regards to electronics is rather limited (understatement). Here's a stupid question, how does the output current relate to output power?
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