[deuginthesky]

Hi there,



Another OP issue.

My father asked me to tweak a bit his old but not bad souding Akai CD player (PCM56 DAC), after opening it I've noticed to DIP8 OPs, both manufactured by Mitsubishi:

-One 5218 7801 written on (could be M5128 OP family)

-the other is 5221 7701 written on, I can not find something corresponding from mitsubishion on http://www.datasheetcatalog.net .

Would someone know what it is ? This OP is in the area of the DAC chip, close to the TC4052BP "DIFFERENTIAL 4-CHANNEL MULTIPLEXER/DEMULTIPLEXER" while the 1st one is just before the RCA plugs.

Thanks in advance.

 

[pmillett]

According to TI Japan cross references... the M5218 is a standard audio opamp interchangable with the 1458 or 4558. The M5221 is a standard JFET input opamp, interchangable with the TLO82.

M5218 data is here:

http://www.chipdocs.com/datasheets/d...orp/M5218.html

or here:

http://pdf1.alldatasheet.com/datashe...SHI/M5218.html

Can't find a datasheet for the M5221.

Pete

 

[deuginthesky]

Thanks pete, I replaced the M5218 by a AD823AN, what a difference !
The sound level is much higher at same level on the ampli. Basses seems deeper and louder. I also put bigger chemi caps: 6800µF + 3300µF instead of 3300µF + 2200µF that may also make a difference + a slight bypass of the output caps.

Rather pleased of that low cost tweak.