My M2 story

[Nelson Pass]

At this time ACA-2 release is dependent on DIYaudio store getting chassis,
power supply and etc together. Circuit and artwork are done.

Preliminary specs:

Three versions in a single chassis with two sinks and one supply
Class A, No feedback
7 watts stereo output into 8, 10 watts into 4 at about 1% thd
20 watts @ 8 ohms mono bridged, 20 watts @ 2 ohms mono paralleled
Nominal distortion at lower levels 0.1%
Gain = 11.3 dB
Input impedance = 50K
Damping factor = 20 @ 8 ohms
Bandwidth 10 Hz to 45 KHz
Noise = 50 uV @ 20-20KHz unweighted

 

[Soundhappy]

....Three versions....

Thanks Mr Pass
Interested by 3 versions and his circuits differences ?
Fascinating little amp's 🙂
Kindest regards

 

[Zen Mod]

same approach as F4

pretty easy and simple , when you see it explained

for more graphical explanation , see F4 manual

 

[Soundhappy]

same approach as F4

pretty easy and simple , when you see it explained

for more graphical explanation , see F4 manual

And surprise too 😀

 

[2 picoDumbs]

At this time ACA-2 release is dependent on DIYaudio store getting chassis,
power supply and etc together. Circuit and artwork are done.

Preliminary specs:

Three versions in a single chassis with two sinks and one supply
Class A, No feedback
7 watts stereo output into 8, 10 watts into 4 at about 1% thd
20 watts @ 8 ohms mono bridged, 20 watts @ 2 ohms mono paralleled
Nominal distortion at lower levels 0.1%
Gain = 11.3 dB
Input impedance = 50K
Damping factor = 20 @ 8 ohms
Bandwidth 10 Hz to 45 KHz
Noise = 50 uV @ 20-20KHz unweighted

 

[2 picoDumbs]

Damping factor of 20 without feedback, that seems higher than normal.
Are we talking a single gain stage driving a single ended source follower output stage?
Or have you added a little pcf?

 

[Nelson Pass]

PCF would be feedback.....

 

[2 picoDumbs]

PCF would be feedback.....

Even cooler.
Ok my first guess has to be right or something like a mu follower set up more follower than mu.
Can't wait.

 

[Sprags]

Is there a board and build guide for the M2?

 

[2 picoDumbs]

Is there a board and build guide for the M2?

Official M2 schematic

 

[Soundhappy]

Is there a board....M2?

I enjoy M2 pcb's amp and psu boards from Tea-Bag member.
You can find them in group buys forum section and ask about.

 

[grimberg]

Is there a board and build guide for the M2?

I still have a few boards left from the group buy. They have a wider spacing between the MOSFETs, but do not match the mounting scheme used by DIYAudio boards. Many people used them and reported success with their builds.

 

[Soundhappy]

M2 pcb´s photo with my work in progress 🙂
And the link :

http://www.diyaudio.com/forums/grou...ds-120mm-ums-spacing-tea-bag.html#post4612640

 

[grimberg]

Mine are shown here:

http://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-72.html#post4975080