Newbie - confused with voltage rating of capacitors ReVox B226 - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 19th March 2016, 11:08 AM   #1
KanedaK is offline KanedaK  Belgium
diyAudio Member
 
Join Date: Feb 2011
Default Newbie - confused with voltage rating of capacitors ReVox B226

Hello,

I'm about to recap my old ReVox B226 CD player.
I started ordering caps: Nippon Chemicon SXE - Nichicon VY (PSU), Elna Silmic II, there will most likely be some Panasonic FC as well

I am however confused with the voltage ratings.
I have been referring to the ReVox service manual for the caps values - sticking to the capacitance and voltage ratings I was reading in there, in the parts list.
For example, all Elna Silmic are going to be 100uF - 16v, as stated in the service manual.
Problem is, when I look at the board with the original caps in place, I see the 100uF that are supposed to be replaced with the Elna Silmic are Philips "blue" caps and are stated 100uF - 25v.
I didn't check yet the other caps, other than the PSU caps where the voltage rating on the cap matches the voltage rating indicated in the service manual.

Am I risking anything? What should I trust, the service manual, or the actual caps that are on the board? I understand caps should be 50% higher rating than the actual voltage that will go trough, for safety. So what is the rating in the service manual? Is it the voltage that goes trough ( in wich case I should order all new caps), or is it the recommanded voltage rating of the cap, and they just used a higher voltage rating because "they had them at hands"?

This is going to be my first serious recap, and I don't wanna mess things up...

thanks folks!
  Reply With Quote
Old 19th March 2016, 11:17 AM   #2
diyAudio Member
 
JonSnell Electronic's Avatar
 
Join Date: Dec 2012
Location: The Jurassic Coast, England. GB
If you plan on changing the capacitors, use as described in the service manual as that is what has been designed. A good idea is to check the actual voltage on the cap that is going to be replaced, just in case. Maybe it has had a re cap in the past and all they had was at hand for their convenience.
No sense in fitting oversized over voltage capacitors.
Philips 'blue' caps are extremely good quality and even an aged capacitor will probably be within tolerance.
__________________
Support for PMC DS-001, (Hypex) UcD400,Valve Equipment and designs both new and old. www.jonsnell.co.uk
  Reply With Quote
Old 19th March 2016, 12:27 PM   #3
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
So what is the rating in the service manual?
The rating in the service manual is the rating specified by the original designer. It will be based on a combination of actual circuit requirements and component availability. Replacements need not be the same voltage rating, provided you can determine from the circuit what the rating needs to be. If in doubt, use the same or the next rating upwards.

In my view a "serious recap" may be a bad idea. More likely to introduce new faults than fix old ones. Replace faulty caps, if any. Do it one at a time, so you can check that it still works.
  Reply With Quote
Old 19th March 2016, 04:44 PM   #4
KanedaK is offline KanedaK  Belgium
diyAudio Member
 
Join Date: Feb 2011
Quote:
Originally Posted by DF96 View Post
The rating in the service manual is the rating specified by the original designer. It will be based on a combination of actual circuit requirements and component availability. Replacements need not be the same voltage rating, provided you can determine from the circuit what the rating needs to be. If in doubt, use the same or the next rating upwards.

In my view a "serious recap" may be a bad idea. More likely to introduce new faults than fix old ones. Replace faulty caps, if any. Do it one at a time, so you can check that it still works.
So even if the caps on the board are rated 25v, I can put some 16v caps in place if that's the service manual states... i'm still confused why the difference, all caps being originals...

As for recapping needed, it's a 1987 player, PSU caps are Frako (i heard those are potential bombs), and I had a total recap on a SAE preamp wich brought it from mediocre sounding to very good... I'm hjoping the same for the ReVox...
  Reply With Quote
Old 20th March 2016, 07:08 PM   #5
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
If the manual states 16V but the board has 25V then you can probably replace with 16V. I assume that the supply rail voltage is less than 16V, and the circuit does not do something unusual to create a local higher voltage. The voltage rating, provided it is sufficient, is not that important. The unit may have been built with some higher rated caps, or it may be the result of a later repair.

Be aware that we regularly get people popping up on here saying "I did a total recap on my XYZ123 to upgrade it, but now it doesn't work". If you must do a recap, at least do it a few at a time.
  Reply With Quote
Old 27th March 2016, 03:40 PM   #6
KanedaK is offline KanedaK  Belgium
diyAudio Member
 
Join Date: Feb 2011
I started soldering new caps yesterday, starting with what I already have - more caps are on their way.
So far I replaced three 2200uF 25v caps with Nippon Chemicon SXE, same values, in the PSU; the big 10000uF I couldn't replace yet, Nichicon FW is on its way. I replaced three small 1uF decoupling caps with Panasonic FC same value; and, as I will have to wait two more weeks for the Elna Silmic II to arrive, I couldn't resist replacing the 100uF output coupling caps with Panasonic FC same value, for the time being.
note: to replace the 4 legs Frako 2200uF, I had to solder some straps made of wire to reconnect tracks that were now left open (in the 4 legs Frakos, the central leg is (+) and the three external legs are (-). Had to look that up last night on the web to figure it out...)

All the other caps on the board I have to wait.

All I must say is I'm very, very satisfied with the result so far; with only a small number of caps replaced, the difference in sound is truly phenomenal! I guess the 30 years old caps had really badly drifted... The B226 is now much more dynamic, highs are clean and extended, bass seems to be faster and stronger, mids are much less harsh than they used to be. There was a roughness to the sound that is now completely gone. I can't wait to have the Elna Silmic and finish the recap, I have big big expectations!
  Reply With Quote
Old 27th March 2016, 03:53 PM   #7
irribeo is offline irribeo  Netherlands
diyAudio Member
 
Join Date: Apr 2013
You are sourcing capacitors in China it seems, will be a modern Revox.
  Reply With Quote
Old 27th March 2016, 04:34 PM   #8
Eldam is offline Eldam  France
diyAudio Member
 
Join Date: Sep 2012
Location: France
There are only 4 reasons to replace caps on a DAC/CD players !

1- you want to secure it because you have nightmares about so said futur troubles !
2- you want to recover the genuine capacity of your beloved player
3- You want to improve Something
4- Wife became borring and you have more fun modding your music stuff!

Well :

- point 4 : can not be talked here, at worst in the swap met section (for instance : "I exchange wife for a dac")

- point 2 : impossible task but if you find NOS stock, and there is agging on the shelf too, so.... impossible task ! And the worst is you can not remember how it sounded when brand new, brain has poor memory of sound !

- point 1 : go for DF96 technic with the caps which feets exactly like the previous (size, pitch, values) . check twice !

- point 3 : go for DF96 : you can only know if the swap is good by hearing if it is not worst before : so component by component (or you are in fact totally in the point or point 2 territory). It is always a long task and it is never a guaranty if you have not the genuine stuff non modded to benchmark the genuine sound ! But it's a good way to adapt your source to your taste or adapt it to the others links of the hifi chain ! It's subjective, but sometimes real improvement can be waited. It can be also a hobby or a game and can beat into the point 4 territory ! A better cap like a better wife on the datasheet can be worst than the original, so you really need to try them one by one (the caps I mean) and listen what they have to said !

Hope that helps !
  Reply With Quote
Old 27th March 2016, 05:50 PM   #9
KanedaK is offline KanedaK  Belgium
diyAudio Member
 
Join Date: Feb 2011
Quote:
Originally Posted by irribeo View Post
You are sourcing capacitors in China it seems, will be a modern Revox.
China? Duh... I didn't buy any chinese cap. I don't really understand your comment.

Modern? well... if you wanna keep using that 1967 Ford Mustang and it needs new tires and maybe new gasket, even tho they will be made with modern materials, you will install them, right?

I don't know what the B226 sounded like when it was new. I was 9 years old in 1987 I guess nobody at this point remembers. Who cares? I guess if it sounds good, and is reliable, it's better than have it taking dust on a shelf. I can really hear a big difference in sound at this point, and for the better. I'm pretty sure it's more due to the facts that the original caps had drifted, rather than their quality; I'm pretty sure Revox used good parts all the way. I'm not derating any cap, to respect the original design as much as possible. I'm not even bypassing any. I'm using same type, same value, same voltage rating even in most cases, and just choose whatever brand I think will be best for this or that part of the circuit. They didn't have Elna Silmic iI in 1987, but I'm sure if they did, they would have used it or something similar. I guess my approach at "modding" is pretty safe, but the end result will tell; I'm confident it will be better than it was when I bought it two months ago, and that's already something.

Eldam, yes I'm using that method: I changed three big PSU caps then listened trough the headphone jack. as what I heard was a clear improvement over the (probably dying and close to shortcut) 30 years old Frako caps, i changed three 1uF (old electrolytics Philips Blue) with Pana FC, and the two output caps (also philips blue) with Pana FC, and now the player is back in the main system and i'm listening some music. There are 21 more caps that I wanna change.

Changing caps on a B226 requires taking the board out completely. I don't wanna put too much mechanical stress on it, as the plastic parts, connectors, ribbons, are old and become fragile with time; hence I won't do the " cap by cap" listening technique. I can do "all same type" but that's enough manipulation already.

Thanks for ur input!

Last edited by KanedaK; 27th March 2016 at 06:08 PM.
  Reply With Quote
Old 27th March 2016, 06:00 PM   #10
irribeo is offline irribeo  Netherlands
diyAudio Member
 
Join Date: Apr 2013
Buying "Nippon Chemicon SXE" today and not some years ago and still two weeks for "SilmicII" to arrive is very chinese to me.
  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
revox B226 CDM4/26 geppo861 Digital Source 1 30th November 2009 02:32 PM
Revox B226 S poynton Digital Source 2 21st January 2008 05:30 PM
ReVox B226, B226-S CD repair tip - (weak laser symptoms) Steerpike Digital Source 1 26th March 2007 08:09 PM
TDA1541A for ReVox B226 David@NY Digital Source 11 26th November 2004 03:05 PM
Revox B226 cd player mevangel Digital Source 0 9th January 2003 05:32 PM


New To Site? Need Help?

All times are GMT. The time now is 11:57 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki