[CosmicHolyGhost]

I am also ordering MUSE01/02 opamp.... but while waiting, I have to say that this is a pretty good sounding portable amp currently using the stock OPA1611... I am using the good line out from DX50... Listening to this stack makes me wonder if Fiio X5 or ZX-1 alone can compete in SQ....
 
 
For people in HKG, labkable carries MUSE opamp, if you order 2 units, it is 350hkd each...

 

[Chefano]

Well,
I need some help to use taobao, but I still have some reservations about it. Any volunteers? =D

 

[earfonia]

I played around with my Velleman Digital Oscilloscope to measure the noise and maximum output voltage of the headphone output of Fiio E12DIY as well as other sources I have on my desk.  The Fiio E12DIY Op-Amp and Buffer combination during the test were AD8620 and LME49600.
 
Maximum output voltage of the headphone output in VAC RMS:
Fiio E12DIY Low Gain: 2.23
Fiio E12DIY High Gain: 7.11
Yulong DA8: 6.75
Violectric HPA V200: 11.74 (measured with Amprobe AM-160 multimeter, as this level is higher than the maximum limit of the digital oscilloscope)
Mytek 192-DSD: 10.00 (measured with Amprobe AM-160 multimeter, as this level is higher than the maximum limit of the digital oscilloscope)
 
As for noise, what shown on the oscilloscope sometime not really correspond with what I heard through IEM.  In this test I use JVC HA-FXD80 for IEM
(which died during the test due to an accident. I forgot that the Mytek was playing 100 Hz tone at full volume when I plugged my favorite IEM on the headphone output... stupid me... very sad 

  now I have to use my second pair of JVC HA-FXD80)
 
All at maximum volume level, from what I heard using IEM, sorted from the lowest noise to the highest noise when playing silent track:
Fiio E12DIY @ Low Gain
Yulong DA8
Violectric HPA V200
Mytek 192-DSD using Digital volume control
Fiio E12DIY @ High Gain
Mytek 192-DSD using Analog volume control
 
The first four in the list, noise level are pretty close.  Fiio E12DIY at lowest gain produce the lowest noise I could hear.  Yulong DA8 headphone output, and Violectric HPA V200 connected to Yulong DA8 through balance connection, produce soft noise at maximum volume level.  Considering Violectric HPA V200 output has the highest output voltage, this is amazing how Violectric HPA V200 can achieve such low noise level at that high amplification (0 dB gain adjustment).
Mytek 192-DSD headphone output with the analog volume control is the noisiest, like about 12 dB louder compared when using digital volume control.  Using digital volume control, the noise is about the same as the Violectric HPA V200.
 
Somehow I don't know how to see the level of noise using the what shown on the oscilloscope.  For example comparing the Mytek output noise, between analog volume control and digital volume control.  They have about the same 1.5 mVAC rms (analog volume slightly higher), and while the digital volume control has higher DC offset, what I hear from the IEM, the analog volume was much noisier than the digital volume control.
Maybe someone knows how to interpret the oscilloscope measurement in relation to the noise level heard from the IEM?
 
Below are screen captures of the oscilloscope, while playing a silent track, and at maximum volume level.
The DC offset of Mytek 192-DSD headphone output is pretty high, but still safe for most IEMs and Headphones.
 
Fiio E12DIY @ Low Gain:

 
Fiio E12DIY @ High Gain:

 
Yulong DA8 Headphone Output:

 
Violectric HPA V200 headphone output, 0 dB gain adjustment, connected to Yulong DA8 through balance connection:

 
Mytek 192-DSD headphone output with analog volume control:

 
Mytek 192-DSD headphone output with digital volume control:

 

[ClieOS]

Here is my report (so far): the DC offset on MUSES02 is pretty low, measured around 0.3mV/1.2mV at low gain or 3.6mV/13mV at high gain. Both are fairly acceptable in my book. On the stock AD8620, DC offset is near perfect with 0mV at low gain and less than 1mV at high gain.
 
Also confirm others' finding that DIP8 will not fit into the case without modding. Those of you who are thinking about MUSES01/02 should really hold your horses and think this through before spending big bucks on opamp that you can't fit onto housing. To have DIP8 opamp fit into the housing, you will need to grind away about 1mm deep slot (as wide as the opamp and about 2~3cm in) inside the case so the opamp can slide in. You can force the DIP8 opamp in but I reckon you will probably break something at some point since there will be a lot of stress on the PCB. I can also confirm that BrownDog adapter (for dual channel opamp only, not 2x mono) will work on E12DIY because it has a low profile.
 
Anyway, I haven't had the time to listen it yet and will report back about the sound of the MUSES series. However, unless you have a small grinder ready to do whatever it takes to have the MUSES installed inside the E12DIY, I'll really suggest you just give up on using the MUSES series in it.

 

[TekeRugburn]

  Here is my report (so far): the DC offset on MUSES02 is pretty low, measured around 0.3mV/1.2mV at low gain or 3.6mV/13mV at high gain. Both are fairly acceptable in my book. On the stock AD8620, DC offset is near perfect with 0mV at low gain and less than 1mV at high gain.
 
Also confirm others' finding that DIP8 will not fit into the case without modding. Those of you who are thinking about MUSES01/02 should really hold your horses and think this through before spending big bucks on opamp that you can't fit onto housing. To have DIP8 opamp fit into the housing, you will need to grind away about 1mm deep slot (as wide as the opamp and about 2~3cm in) inside the case so the opamp can slide in. You can force the DIP8 opamp in but I reckon you will probably break something at some point since there will be a lot of stress on the PCB. I can also confirm that BrownDog adapter (for dual channel opamp only, not 2x mono) will work on E12DIY because it has a low profile.
 
Anyway, I haven't had the time to listen it yet and will report back about the sound of the MUSES series. However, unless you have a small grinder ready to do whatever it takes to have the MUSES installed inside the E12DIY, I'll really suggest you just give up on using the MUSES series in it.

 
I have a dremel tool so I'm not too worried about it fitting.  I'm fairly decent at soldering never smd or the sort.  Let's see how this goes lol.  

 

[K.T.]

This is getting into some nice DIY territory. I'm sure some of us won't blink an eye at pulling out the tools and doing whatever it takes.

One other option is testing out the Muses with the cover off. If one falls in love with the sound, one could desolder the socket and hardwire the Muses chip into the amp. I'm thinking the chip would fit in the stock case without the extra height of the socket. That's just a thought. I haven't actually looked inside the amp to see if it's doable.

Of course, if one were to go that route, one would be wedded to the Muses chip and the amp would no longer be a test platform for any other op amps. Only for the buffers.

So 2 low profile soic OPA627s on a BrownDog adapter won't fit? Still too thick? I'm curious if the OPA627 sounds good in this application.

Is there a difference in sound between Muses 1 and Muses 2, btw? Not a whole lot of English language discussion that I could find comparing the two.

 

[CosmicHolyGhost]

MUSES wont fit

Any other recommendation of Opamp?

 

[TekeRugburn]

This is getting into some nice DIY territory. I'm sure some of us won't blink an eye at pulling out the tools and doing whatever it takes.

One other option is testing out the Muses with the cover off. If one falls in love with the sound, one could desolder the socket and hardwire the Muses chip into the amp. I'm thinking the chip would fit in the stock case without the extra height of the socket. That's just a thought. I haven't actually looked inside the amp to see if it's doable.

Of course, if one were to go that route, one would be wedded to the Muses chip and the amp would no longer be a test platform for any other op amps. Only for the buffers.

So 2 low profile soic OPA627s on a BrownDog adapter won't fit? Still too thick? I'm curious if the OPA627 sounds good in this application.

Is there a difference in sound between Muses 1 and Muses 2, btw? Not a whole lot of English language discussion that I could find comparing the two.

 
well it is called E12DIY

 

[earfonia]

I'm not sure if Muses Op-Amp is thicker than other regular DIP-8.  On my case, I tried a few DIP-8 Op-Amp, OPA2134, OPA2604, and OP275, all touches the aluminium case, but not over it, so I can slot the board in without any stress, just nice fit.  Also tried AD8066 on DIY SOIC to DIP, still has some space as shown in the picture.  Maybe our aluminium cases differ slightly?  Lucky me, I can tried any DIP-8 without having to DIY the case
 
Stock AD8620:


 
AD8066 on DIY SOIC to DIP:


 
Regular DIP-8, OPA2134, OPA2604, & OP275:

 

 

 

 

[earfonia]

  Here is my report (so far): the DC offset on MUSES02 is pretty low, measured around 0.3mV/1.2mV at low gain or 3.6mV/13mV at high gain. Both are fairly acceptable in my book. On the stock AD8620, DC offset is near perfect with 0mV at low gain and less than 1mV at high gain.
 

 
Excellent, thank you!
That 0.3mV/1.2mV at low gain is for left and right channels right?

 

[ClieOS]

So 2 low profile soic OPA627s on a BrownDog adapter won't fit? Still too thick? I'm curious if the OPA627 sounds good in this application.

Is there a difference in sound between Muses 1 and Muses 2, btw? Not a whole lot of English language discussion that I could find comparing the two.

 
Yep. Two SOIC on both side of the adapter will be way too thick. It has to be side-by-side like the FiiO adapter to work.
 
I haven't tested MUSES01/02 on E12DIY yet, but I have used both on other places. They are definitely not alike, and generally speaking in circuit where both can be used, MUSES01 almost always sound better.
 

   
Excellent, thank you!
That 0.3mV/1.2mV at low gain is for left and right channels right?

 
Yes, left/right channel.

 

[Shiikamaru]

would like to ask. i have just received my e12diy. the metal box came with a lot of pcb. i have taken out those listed on the last page of the instructions and i am left like 8 pcbs without anything on it. would like to know whats it for? and im having a hard time pushing the body out of the casing. theres like grinding noise when im pushing it in and out. is that normal?

 

[ClieOS]

  would like to ask. i have just received my e12diy. the metal box came with a lot of pcb. i have taken out those listed on the last page of the instructions and i am left like 8 pcbs without anything on it. would like to know whats it for? and im having a hard time pushing the body out of the casing. theres like grinding noise when im pushing it in and out. is that normal?

 
The blank PCB are for those who wanted to try other opamp / buffer.
 
There is some sticker inside. You don't need to push the whole PCB out. As long as you have good access to the opamp and buffer section, you are okay.

 

[K.T.]

OK, it is good to see that DIP package MAY be able to fit into the case. That bodes well for the Muses.

The clearance in the picture is very small, so I wonder if it comes down to manufacturing tolerances from amp to amp? Maybe some will allow the DIP to slide in and others will not?

We are talking about like a millimeter difference, here. Something like how closely the socket was pressed to the board before it was soldered may make all the difference.

I for one am still very curious about the Muses. If they really sing more sweetly than the others, I will have no trouble breaking out my Dremel to grind out some clearance.

Incidentally, if the Muses 1 trumps the Muses 2, why does the 2 exist, and in what instances would you use it over the 1?

 

[ClieOS]

In the spirit of DIY, I took the time to sand down the case so it will accommodate a DIP8 packaged opamp better.
 

 
I used some masking tape just to mark the area that needed to grind down. You will have to go about as deep as the microUSB opening, around 23mm or so.
 

 
I took out roughly 1mm or so in material, basically half-ing the overall thickness.
 

 
 
Now the DIP8 opamp sitting flush inside the case without bending the PCB or applying any stress.