Marantz CD75 - Any info? - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 2nd November 2004, 08:50 PM   #1
Duncan is offline Duncan  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: Bedfordshire
Default Marantz CD75 - Any info?

Hi All...

I picked up a Marantz CD75 from a pawn shop for the equivilant of $30 today, it proclaims to be a 'Digital Monitoring CD Player' (i'm guessing that means it has a digital output on the back-plate), and i've opened it up, and its full of Elna Cerafines, and has a Philips TDA1541 as its DAC (with a 'Z-Filter')...

...It looks like the previous owner might've modded it a little, the original timing crystal is still there, but there is a small inverted circuit board in between the crystal and the DAC, that looks to have been installed a little haphazardly...

Sounds pretty good... once its settled in a little, i'll compare it to my CD850... but just wondering if anyone here knows its vintage etc (as there appears to be nothing on search engines)

Thanks
  Reply With Quote
Old 2nd November 2004, 10:20 PM   #2
Duncan is offline Duncan  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: Bedfordshire
it also looks like someone has had a go at re-doing the caps...

Dial-Up Warning - Large Image!! so you can see the cerafines, and that green square I was reffering to in my last post...

Any ideas or help in working out what that green thing is will be majorly appreciated

Thanks
  Reply With Quote
Old 2nd November 2004, 10:56 PM   #3
guido is offline guido  Netherlands
diyAudio Member
 
guido's Avatar
 
Join Date: Mar 2002
Location: diepe zuiden
Looks a lot like a CD650 main pcb. My guess is that the small pcb comes from the factory. Think that because of the markings on it.

The xtal next to the 7220 is connected to that chip, not to the dac.
Your 'modification' is connected to pen 23 of the 7220, which is the mute coming from the MAB to the dig filter. My guess it is a last minute mod because they could not get the correct MAB..

My 650 had a similar pcb, but that even contained the mab and some logic stuff on a bigger separate pcb. Just because they did not get the controller right first time (or using older versions still in stock, or ...). I got a MAB from a later cd650 version and it was a nice drop-in for the complete pcb!

So you can still do a clock-mod Next time you take a pic like that, open the drawer. Then we can also see the cdm used, my guess is a dark-green cdm2.

Send me a pm for the 650 schematics, you can get a good way with those (but i can see small differences, near connector to front pcb)

> wat een kl*tedag vandaag! < (offtopic, we had a bad day)
__________________
GuidoB
  Reply With Quote
Old 3rd November 2004, 08:23 AM   #4
Van Hai is offline Van Hai  Hong Kong
diyAudio Member
 
Join Date: Oct 2003
Location: HOng Kong
I've been use this CD player for many years till now, good transport, it can read almost anything. Hard to find a remote. i use it connect to my dac.

from the pic your have been mod. OPamp it was LM833.

cheer
  Reply With Quote
Old 3rd November 2004, 10:21 AM   #5
tubenut is offline tubenut  South Africa
diyAudio Member
 
tubenut's Avatar
 
Join Date: Nov 2002
Location: South Africa, Jhb
Default Quite sure it uses CDM2

Quite a nice machine, lots of mods possible. If it uses LM833 replace those quickly, even 5532 is far better sounding. Diodes also make a big difference.

Any RC5 remote should operate the player...

Guillaume
  Reply With Quote
Old 3rd November 2004, 07:52 PM   #6
Duncan is offline Duncan  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: Bedfordshire
Default Re: Quite sure it uses CDM2

Quote:
Originally posted by tubenut
Quite a nice machine, lots of mods possible. If it uses LM833 replace those quickly, even 5532 is far better sounding. Diodes also make a big difference.

Any RC5 remote should operate the player...

Guillaume
This player has JRC op-amps in (although if my memory serves correctly, JRC copy other manufacturers ICs... so this could be right on the money... If the 5532s are a straight swap, then I might do that at the weekend as I have a couple spare right now...

Also, I would have agreed with you about the remote control, seeing that Philips and Marantz were for quite a while the same company - but my Marantz CD63SE remote (which works my Philips CD850 perfectly) doesn't work at all on this CD75 (I have made sure that the remote switch at the back is set to internal)

Maybe the remote sensor is dead...

Thanks for the replies
  Reply With Quote
Old 4th November 2004, 05:12 AM   #7
tubenut is offline tubenut  South Africa
diyAudio Member
 
tubenut's Avatar
 
Join Date: Nov 2002
Location: South Africa, Jhb
Default Maybe sensor is dead

I have not used other remotes with a CD75 but it is from the same era as some other philips units like cd471 and that remote works many players...

What JRC op amps does it use? The NJM2114 is a copy/equivalent of the 5532 and Marantz preferred it, using it as an SE upgrade on things like the CD50 that had 5532 as standard. I went through many dual op amps in a QED digit dac and the 2114 sounded better to my ears then the 5532.

You may also find an improvement by bypassing the safety resistors on the op amp supply pins. Never seen one actually fuse so it is quite safe to do. I am sure the resistors cause a slight voltage drop and some modulation.
These resistors, if removed also give beautiful access to the op amps for a dedicated separate audio supply....... A trick that would work on most Philips based players from the era up to about 1997 or so.

Oh yes, also stick an RCA pl;ug with a 75 ohm resistor across the digital output. It works wonders on virtually all players that have their digital out permanently enabled.....

Regards
Guillaume
  Reply With Quote
Old 4th November 2004, 06:40 PM   #8
Duncan is offline Duncan  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: Bedfordshire
hi tubenut.

the op-amps are JRC6045s, and it says above that 5532

I think i might socket them, and try some AD823s or OPA627s
  Reply With Quote
Old 5th November 2004, 04:58 AM   #9
tubenut is offline tubenut  South Africa
diyAudio Member
 
tubenut's Avatar
 
Join Date: Nov 2002
Location: South Africa, Jhb
Default Careful, 5532 is a dual op amp

I think the OP627 is single but play with OPA2134 and 2604....
It has always baffled me that 5532 is dual and 5534 is single, Philips logic?????

Your CD850 should be a canditate for single op amps. I really liked the OP176 I think it was when I had my CD850.

Guillaume
  Reply With Quote
Old 6th November 2004, 09:42 PM   #10
Duncan is offline Duncan  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: Bedfordshire
Default Re: Maybe sensor is dead

Quote:
Originally posted by tubenut
Oh yes, also stick an RCA pl;ug with a 75 ohm resistor across the digital output. It works wonders on virtually all players that have their digital out permanently enabled.....

Regards
Guillaume
...I'd not heard of this tweak before...

I bought a nice plug, and a resistor, came in at 1.05, and it seems to, as you say - make things markedly improved...

Thanks a lot!

Duncan.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Service Manual Request: Marantz CD75 MkII or CD65 MkII jeff mai Digital Source 9 23rd April 2009 04:48 PM
Marantz CD85 - any info? Rotellian Digital Source 1 4th June 2008 07:16 PM
Marantz CD75 mk II service manual plz TJ Digital Source 3 21st February 2007 06:05 PM
Marantz CD75 SE MarkII help required lostintheozone Digital Source 6 7th September 2006 08:45 AM
Info about Marantz CD 11 Mk2 Maurizio Digital Source 1 16th September 2004 09:53 PM


New To Site? Need Help?

All times are GMT. The time now is 11:20 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2