Ive upgraded my Marantz CD75MK2, CD50SE (bought that one modded), and Philips CD850MK2. used LM4562 in all with great results. I think they make LM4562 with the pins? Other contenders to use? they are smd type
I am upgrading the caps in my lower spec Technics SL-P350, and want to change the opamps in it and my higher end Techncis P990. I assume they are dual amp opamps.
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P990 service manual is a bit confusing , i know the IC amplifer is opamp, not sure what buffer amp, should be changed also
I am upgrading the caps in my lower spec Technics SL-P350, and want to change the opamps in it and my higher end Techncis P990. I assume they are dual amp opamps.
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P990 service manual is a bit confusing , i know the IC amplifer is opamp, not sure what buffer amp, should be changed also
Opamps are often used in power supplies and the servo and motor drive circuits of CD players. I would not replace any of these, doing so may well alter the alignment of the servo systems.
From that list I would suggest that only the 5532's are in the audio path.
From that list I would suggest that only the 5532's are in the audio path.
Create for yourself a schematic.
Probably an OP is used for a simulated inductance. They are not directly in the signalpath and needn't to be replaced by another type. I worked on an old Denon CDP and the OPs in the output area are all used as this type of inductance.
Probably an OP is used for a simulated inductance. They are not directly in the signalpath and needn't to be replaced by another type. I worked on an old Denon CDP and the OPs in the output area are all used as this type of inductance.
Hi S4m,
Thank you. I am a bit confused so they are not directly in the signal path, and dont need to be changed. P990 certainly is a different set up, also has a relay thingy near the output
Thank you. I am a bit confused so they are not directly in the signal path, and dont need to be changed. P990 certainly is a different set up, also has a relay thingy near the output
If you are a little bit more interested in the function i recommend you this article:
Audio Designs With Opamps
The relay can be the muting function probably. In my Denon CDP the muting circuit had been done with transistors. For reworking my CDP I took this as a type of guide:
Fikustransport
Also the guide of Mooli:
http://www.diyaudio.com/forums/digital-source/226288-sony-cdp790-kss240-restoration-project.html
This helped me a lot for checking the basics without missing a step.
Audio Designs With Opamps
The relay can be the muting function probably. In my Denon CDP the muting circuit had been done with transistors. For reworking my CDP I took this as a type of guide:
Fikustransport
Also the guide of Mooli:
http://www.diyaudio.com/forums/digital-source/226288-sony-cdp790-kss240-restoration-project.html
This helped me a lot for checking the basics without missing a step.
You need to study the circuit to see what the various devices do. The relays are just for signal muting (on/off and possibly for red book compatability with multi lingual CD's)
Thanks S4M for the links. I was lucky enough to buy a lampizator Marantz CD50SE NOS from the UK a few years back. I changed the VR Nichicon around the DAC to Fine Gold and Mooly, I'll try to go over and follow the traces
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Under PCB - opamps
An externally hosted image should be here but it was not working when we last tested it.
Opamp near output
An externally hosted image should be here but it was not working when we last tested it.
audio section pcb
the opamp at near the output would be once that could be changed?
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Without circuit details you are guessing.
Probably fair to say all the 5532's are in the audio path, quite possibly with no channel sharing either (each device for one channel). The two white pots ? what do they do ? Do you need to trim any offsets with those ?
You could end up making things worse.
Probably fair to say all the 5532's are in the audio path, quite possibly with no channel sharing either (each device for one channel). The two white pots ? what do they do ? Do you need to trim any offsets with those ?
You could end up making things worse.
Thanks Mooly, yes the P990 is complicated, and yes maybe it is not so upgradeable without affecting the trimpots? there is orange ones also, maybe the same thing. As is a very nice sounding CD player. Gold has worn from the RCA sockets a bit, least i have the board out i might upgrade those.
Main thing is the P350 since I am the process of recapping. I got my parts from hificollective, so a bit of a wait to Australia. I wonder if both opamps need changing in the audio section, definitely the one near the output. 5532 and 4558. I hope both are dual. LM4562 seems very liked, there is a new version of it LME49860, i think it has higher voltage.
Main thing is the P350 since I am the process of recapping. I got my parts from hificollective, so a bit of a wait to Australia. I wonder if both opamps need changing in the audio section, definitely the one near the output. 5532 and 4558. I hope both are dual. LM4562 seems very liked, there is a new version of it LME49860, i think it has higher voltage.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
