DIY Discrete regulators - 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 1st February 2008, 01:32 AM   #1
gareth is offline gareth  Wales
diyAudio Member
 
gareth's Avatar
 
Join Date: Jan 2008
Default DIY Discrete regulators

Hi, I am fairly new to this DIY scene and was wondering if it would be possible to build my own discrete regulators to be used with my Marantz CD 63se.

I know there are commercial versions availble using SMT components, but still I would like to try.

What I have seen fit straight into where the existimg LM... type regulators are.

Any help would be appreciated.

Thanks
Gareth
  Reply With Quote
Old 1st February 2008, 08:37 AM   #2
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Hi Gareth, Yes it's possible of course to make a discrete version of a 3 pin regulator, but the the performance of even standard 78xx types is so good you could easily end up with a much poorer supply. Semiconductor manufacturers invest millions in design and it's wishful thinking to think a handful of discrete components will do a better job. That's not to say it's not good fun of course If you want to try tweaking you're player check out some of the other mods first, op-amps and so on. If you make a mistake on a P.S.U. you could easily right the player off. If you are intent on making a discrete regulator I would suggest making one first as a separate project and fully test it (noise, regulation, dropout etc) on the bench rather than in the player.
Regards Karl
  Reply With Quote
Old 1st February 2008, 09:57 AM   #3
diyAudio Member
 
Join Date: Jan 2002
Location: Cheltenham
Here's a good one to try:

http://www.audioasylum.com/forums/pc...s/2/24191.html

Dan
  Reply With Quote
Old 1st February 2008, 11:06 AM   #4
gareth is offline gareth  Wales
diyAudio Member
 
gareth's Avatar
 
Join Date: Jan 2008
Quote:
Originally posted by Mooly
Hi Gareth, Yes it's possible of course to make a discrete version of a 3 pin regulator, but the the performance of even standard 78xx types is so good you could easily end up with a much poorer supply. Semiconductor manufacturers invest millions in design and it's wishful thinking to think a handful of discrete components will do a better job. That's not to say it's not good fun of course If you want to try tweaking you're player check out some of the other mods first, op-amps and so on. If you make a mistake on a P.S.U. you could easily right the player off. If you are intent on making a discrete regulator I would suggest making one first as a separate project and fully test it (noise, regulation, dropout etc) on the bench rather than in the player.
Regards Karl

Cheers Karl, I assume that I would need an oscilloscope for testing and fine tuning ? Would I need a signal generator ?

In respect of the op-amps, is it simply a case of a straight swap with the existing ones or will I have to change resistance/capacitance on the PCB ? Do you have any suggestions ?

Thanks
Gareth
  Reply With Quote
Old 1st February 2008, 11:12 AM   #5
gareth is offline gareth  Wales
diyAudio Member
 
gareth's Avatar
 
Join Date: Jan 2008
Quote:
Originally posted by Spartacus
Here's a good one to try:

http://www.audioasylum.com/forums/pc...s/2/24191.html

Dan

I AM SPARTACUS ! Right anyway, thanks for the link Spartacus. This seems like an achievable design. Do you agree in that it may not be worthwile in trying to produce these ?

NO I AM SPARTACUS !

Thanks
Gareth
  Reply With Quote
Old 1st February 2008, 12:00 PM   #6
diyAudio Member
 
Join Date: Jan 2002
Location: Cheltenham
Hi Gareth,

definately worthwhile building you own. Take a look at this thread:

SKA Audio
  Reply With Quote
Old 1st February 2008, 12:10 PM   #7
Mooly is online now Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Have you looked at the "Marantz cd63 cd67 mods" thread on this forum ? It's just below you're thread at this moment. About 450 pages at the last count ! I find one of the easiest and most effective ways to clean up the power supply is to add a 0.1 mfd surface mount cap directly under each elecrolytic. This counters the rise in impedance of the caps at H.F. and assuming a 5mm pitch they can be added so that they look like original fitment. As for op-amps, it depends what is fitted, dual or single. I have had very good subjective performance with OPA604 (single) and OPA2604 (dual). Let us know how you get on.
Karl
  Reply With Quote
Old 1st February 2008, 12:14 PM   #8
00940 is offline 00940  Belgium
diyAudio Member
 
Join Date: Sep 2003
Location: Paris
It is not that difficult to improve over lm78** regulators if you follow well known designs for which PCBs are available (such as the Jung or Sulzer) or simply use a lm317 with some tricks (see : http://www.acoustica.org.uk/ ).

However it is not quite certain that you will get actually improved performances if you just want something that fit into the holes of the previous regulators. The layout of the board (grounding especially) is playing a big part in the performances of regulators.

Easy to build discrete regulator (from Jocko Homo) :

http://www.diyaudio.com/forums/attac...amp=1070501103
__________________
Ben.
  Reply With Quote
Old 1st February 2008, 12:33 PM   #9
pilli is offline pilli  France
diyAudio Member
 
Join Date: Aug 2006
Quote:
Originally posted by Mooly
(...) make a discrete version of a 3 pin regulator (...)
(...) the performance of even standard 78xx types is so good (...)
(...) wishful thinking to think a handful of discrete components will do a better job (...)

(...) check out some of the other mods first (...)

...I hope I'm not misunderstanding something (surprised that nobody reacted before) but it is definitely possible and reasonably easy to do better than the 78xx.

I am really not that good, yet I was able to implement Jung regulators. These are probably not considered the easiet, but based on Jung's and Jan Didden's articles, it's almost "Lego".

My implementation is sure not "impeccable" and yet the improvement over 78xx/79xx (on a Denon DCD-1560) is really astonishing (firmer bass, clearer cleaner sound, air and definition, to describe quickly). We're not talking nuances, it is a definite improvement, tested before and after against the same reference.


Just one of many possible introductions into this subject, and for a summary of good search words, you can start looking at this:
http://tangentsoft.net/elec/opamp-linreg.html

Then spend some time in these forums, you'll find all you need.



...ok, these are not completely "drop-in" to the 78xx, but really, I could make it work using no more than voltmeter and soldering iron and two additional screened cables for "rs".


Then I fully agree with Karl:

- Test "outboard" before installing, at least the output voltage upon different inputs (load with a R+LED is enough)

- Try the other mods too (some are quite "drop-in", though not risk-free)

- Do it on a "disposable" player (get a cheapo on eBay; better, get two of the same and keep one stock, as reference for comparing on improvements)



But by all means, give it a try.




_
  Reply With Quote
Old 1st February 2008, 12:36 PM   #10
gareth is offline gareth  Wales
diyAudio Member
 
gareth's Avatar
 
Join Date: Jan 2008
Quote:
Originally posted by Mooly
Have you looked at the "Marantz cd63 cd67 mods" thread on this forum ? It's just below you're thread at this moment. About 450 pages at the last count ! I find one of the easiest and most effective ways to clean up the power supply is to add a 0.1 mfd surface mount cap directly under each elecrolytic. This counters the rise in impedance of the caps at H.F. and assuming a 5mm pitch they can be added so that they look like original fitment. As for op-amps, it depends what is fitted, dual or single. I have had very good subjective performance with OPA604 (single) and OPA2604 (dual). Let us know how you get on.
Karl

So how do I know which type, single or dual, op-amps I should use ?
  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
Bipolar discrete shunt regulators cetoole Solid State 589 24th August 2011 11:25 PM
discrete voltage regulators from different manufactures, are they all equal? KevinLee Parts 5 5th November 2008 01:44 PM
My take on regulators Cauhtemoc Solid State 38 31st August 2007 05:53 AM
+/- with pos and neg regulators vs 2 pos regulators mr.duck Power Supplies 8 12th October 2006 05:27 AM
Discrete voltage regulators. JoeBob Solid State 1 18th March 2002 06:25 AM


New To Site? Need Help?

All times are GMT. The time now is 12:09 PM.


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