Re: Repairing Alesis M1 Active mk2 Monitor Speakers
Hy. There are 6 months now and they are working fine. With UC3842 it`s ok.
Shabazxz
Member
Last Activity: 11-18-2017, 11:27 AM
Joined: 02-18-2017
Location: Bacau
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
Any ideea?Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
On the schematic the fuse F1 have 10A, on the board it`s write 5A and i put 5A fuse.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
I mesured all the FETs and all the diods. All good. I change the U1 with the UC3842 and work again. Luck me, i ordered one 3844 and one 3842. Why the U1 died?Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
Hy all.Unfortunately the fuse blew again. I will disassamble the speaker again.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
When i disassembled the speaker, i disassembled and the part with the inputs.
And i discovered that, when i push that part (on the bass/mid....switchs) the speaker make that noise. So i must take out the board with the inputs and to check what i did wrong.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
I will record the noise. He made the same noise with no signal and with volume(gain) to minimum. Strange after 4 hours the M1 works fine with no noise.
I will let them (both) without the power cord tonight .Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
I let them "working" on moderate volume and after 30 minutes the bed one started to make some sounds like an echo . Only for 10 sec but repeted. I have changed the dac, the whires.
Any ideas?Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
I changed the U1 with UC3844N like u said and it`s working
.
I took out the bad U1 and replaced with one dip8 socket.
I changed the C8 and C35 in the good one and i moved the C8 on the other side of the board (both).
Thanks !!!Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
R15 - 0.25ohmLeave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
The esr metter has arrived.
R3, R4 - 38k
R15 -0.25k
C7 - 380, C8 - 390
C16 - 650nf (on schematics it`s write 160V, but on the C16 it`s written 100V)
The parts tomorow.Last edited by Shabazxz; 03-06-2017, 08:22 AM.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
I will replace only what it`s bad. But all cost 15E and i order them just in case (anyway i will check C8 on the good one and i will change the place of C8)...
Sorry, not R5, D15, i order R15 and D5.Last edited by Shabazxz; 02-28-2017, 01:36 PM.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
Ok. I hope tomorow U1 will arrive. I request the UC3844N and UC3842N, FETs, R5, C8, Q3-7, D15 and one ESR meter. And one DIP8 socket. First i will check the components from the board and if some one it`s broke i will change it. If all are good, i will change the U1 (UC3842N like on the board) and after i will test with the bulb.
What power must be the bulb? 10,15,40..W?
Thanks!!Last edited by Shabazxz; 02-28-2017, 12:18 PM.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
Strange. On the good board it`s 330. On the bad one, C8 was changed (not by me. i recived like this. It was repaired once) with 220uf.
On my board R1,R2, C3,C4 is missing.Last edited by Shabazxz; 02-28-2017, 07:30 AM.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
And if i change the place between C8 and C14?Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
I have the same revision of the board (only the parts. C8 it`s near R4 on my pcb)
So i must change C8. Now i have 220 like in the schematic....Last edited by Shabazxz; 02-28-2017, 05:30 AM.Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
Alesis M1 620 is the M1 MK3. And the power supply it`s the same. But the U1 it`s other.
I don`t know witch it`s better.
3842 or 3844Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
M1 620 it`s the 3 edition. Am the power board it`s reversed. So i can move the C8 on the back. I don`t understand why did they removed the power button.
There is no stand-by on these monitors and the only way to shut down it`s to remove the cord from the wall.
Please tell me what it`s the correct U1?
ThanksLeave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
i will replace R15 on boath board. On the good one i will change the C8 .Leave a comment:
-
Re: Repairing Alesis M1 Active mk2 Monitor Speakers
on the schematic the U1 is UC3844N, and on the board on the U1 it`s written 3842 and below5E02.
What it`s the correct IC?Leave a comment:
No activity results to display
Leave a comment: