Hey all,
thought I would share my upgrades on the my M1 DAC.
I was inspired by this article by Liquid Audio in Australia...
https://liquidaudio.com.au/musical-fidelity-m1-dac-review-upgrades/
and his companion video here...
My unit is laid out a little different. I think his is a 1st gen. Mine is from 2012 after they fixed the Asynchronous USB issue.
I pretty much followed his prescription except that instead of using Elna Silmic II's in some key places I used Nichicon Fine Gold's in those spots. Also, I bypassed the bi-polar Muse output coupling capacitors with Kemet's instead of Wima's. Otherwise, I used Panasonics in the Power supply.
Also, I replaced the 1N4007 diode bridge with SBYV26 super-fast, slow-recovery type diodes. Not sure how much difference this made since the bridge is before the switch mode PS section.
I didn't replace the NE5532 opamps as I wasn't expecting SMD components. But luckily there are parallel mounting holes for DIP-8 packages if I want to come back in and do that.
I wish I could report on incremental improvements, but I just shotgunned it. Overall I think it cost about $25 in parts. Hard to say since I was placing an order from Mouser and threw this on top of the larger order. Timewise, I guesstimate about 4 hours total in labor. I was interrupted several times. After an initial test to make sure everything was working I put it in the living room system and left it streaming Spotify all night.
I always liked this DAC, but never thought it was anything special. Just a good DAC. Overall I think these upgrades really made it shine. I've only spent about an hour really listening critically today. Did the clouds part and a ray of audiophile bliss lift me off my feet? No. Is it now a giant slayer taking on units 20X it's price? No. But, does it now sound much less congested? Yes. Does it now sound less spitty and sibilant? Yes. Do I think the cost/reward ratio was worth it? Definitely!
I know it's two different approaches, but now compared to the Counterpoint DA-10 that I'm used to in the living room, the M1 compares very favorably. Before there was no real contest. Now I will have to spend more time to determine which one I prefer.
(note: the above is comparing Optical and Coax only, I don't use USB)
Getting started:
View attachment 1756242
Board before mods:
View attachment 1756241
Diode bridge:
View attachment 1756240
Boards after:
View attachment 1756239
View attachment 1756238
View attachment 1756237
Note the SMD output buffer chips, but there are for DIP parts!
View attachment 1756236
Chassis damping:
View attachment 1756235
All the parts that were replaced:
View attachment 1756234
Comparing it to the Counterpoint DA-10
View attachment 1756233