[jasperdany]

Hi,

I built the preamp based on the assembly guide. I forgot to perform the tests from the setup guide and when I connected to my Wes audio chassis, everything was fine (no smoke). My Wes audio was not connected to my audio interface, so I connected it to my Cranborne 500R8, the DI input did not work, I saw line level input signal and LED blinking, but no output signal and within a few minutes, I saw smoke, I removed the module and am not able to find which component emitted the smoke. Also the preamp is not working. Any suggestions on what I can do ?, or how to fix it ?

[JPK]

You can start with the MP512 check list (the MP12 and MP599 share the same PCB).
https://www.soundskulptor.com/forum/index.php?topic=15.msg15#msg15

[jasperdany]

Hi,

sorry for the delayed response, I just got my tester kit fixed. I noticed, without DOA and DI board, with Jumper on JMP1, I get around 5V between 0V and TP2. When I connect the DOA, the DOA gets really hot and I smell something hot. Is there something wrong here ?

Greetings
Jasper Lawrence

[JPK]

The issue is in the DOA.
Start here.

[jasperdany]

Hi,

I replaced with another DOA, which I already have and I must say the mp599 sounds so good , but unfortunately my DI (High Zi) is not working. When I connect my bass guitar, the XLR input behind, gets cut, that works fine (I can also hear the relay click when I insert my HiZi cable), I do not see any input signal. Is there any thing I could do ?

[JPK]

Check that you inserted Q2 in the right holes (position A).
Can you measure the signal from the DI input on the test pin TP4 (against 0V), measured with our AC voltmeter?

[jasperdany]

Hi,
I think I found my issue, both the diodes are soldered in the wrong direction. I assume this should solve the issue ?.. If incase I damage the part, what terminology should I use to purchase that diode ? . Will 1N914 Signal diode work ? 
 

[jasperdany]

Hi,
The position of Q2 is fine.

[jasperdany]

When I place the final plate, it touches the top of Capacitor C9, is that okay ?. Sorry I could not paste all the images and questions under 1 reply.

[JPK]

both the diodes are soldered in the wrong direction
This is the issue for sure. The diodes may have survived.

Will 1N914 Signal diode work ?
Yes.

When I place the final plate, it touches the top of Capacitor C9, is that okay ?
This is not a problem.

[jasperdany]

Hi,
after I desoldered, I noticed the legs are too short to switch sides. I noticed the previous link I sent you has a long shipping time, so will this IN914 Diode and IN4148 Si-Diode also work ? They have faster delivery times

Greetings,
Jasper

[JPK]

Yes to both.

[jasperdany]

Hi,

I got the diodes today, I soldered them correctly this time, and it works. Everything is super !!! ... Thanks for the support   

[JPK]