If you mean replace the one 7805 with one 'Raygulator' I personally don't think it would be worth the effort if you're later going to separate them. Just my opinion though so please try it if you can be bothered. It may stop some more of the servo noise than the 7805 does.
Don't put low-ESR capacitors right at the output of a LM317 though (especially OS-CON). Use ordinary ones and save the good ones for next to the chips (where they are far enough away to not cause ringing with the inductance of the LM317 output).
Read Werner Ogiers crash-course on voltage regulators on tnt-audio.com for enlightenment.
Don't put low-ESR capacitors right at the output of a LM317 though (especially OS-CON). Use ordinary ones and save the good ones for next to the chips (where they are far enough away to not cause ringing with the inductance of the LM317 output).
Read Werner Ogiers crash-course on voltage regulators on tnt-audio.com for enlightenment.
Oh, you just need R2 to be three times bigger than R1 for 5V.
Vout = 1.25 x (1+(R2/R1))
So you could use 330R and 1K.
120R and 360R also works and means you always draw at least 10mA even with no load, but if you will draw more than this anyway higher divider resistors will mean the adjust-pin bypass capacitor is more effective so use higher values.
The only thing you could power that will draw <10mA is the clock invertor gate or DAC output stage.
I'm no expert here though, so hopefully Martin will chime in with more tips!
Vout = 1.25 x (1+(R2/R1))
So you could use 330R and 1K.
120R and 360R also works and means you always draw at least 10mA even with no load, but if you will draw more than this anyway higher divider resistors will mean the adjust-pin bypass capacitor is more effective so use higher values.
The only thing you could power that will draw <10mA is the clock invertor gate or DAC output stage.
I'm no expert here though, so hopefully Martin will chime in with more tips!
Do not consider my advicew as expert,I just converted that to NZ dollars got a fright at the cost🙂 Can tranformers of similar specs be that much different between vendors?
Luke said:
It's because it's custom made. It will be instrumental in making the amp sound exceptionally good, I'm sure of that much. But £200 worth of good? I'm not entirely sure of that. For a lot less I could buy a huge toroid... but it has been said many times a toroid will always produce a colder, less involving sound.
Simon,
do they not have a transformer thats close enough to your requirements, probably alot cheaper than a custom job. I have never heard that before about toroidals, I thought they are the best for audio?
do they not have a transformer thats close enough to your requirements, probably alot cheaper than a custom job. I have never heard that before about toroidals, I thought they are the best for audio?
Im not entirely happy with my modded cd6000 or 67. I have used bucket loads of C before and after the 7805, I thing it has improved the bass but the players seem slower less rythem (thats hard to spell) less musical. Pedja claims that less is best with digital supplies so Im thinking I wills tart again with some raygulators.
Pedja claims he experimented and ended up with less than the factory players capacitance. Think he said 100uF was all he used.
Maybe I should buy another one and start over again🙂
Pedja claims he experimented and ended up with less than the factory players capacitance. Think he said 100uF was all he used.
Maybe I should buy another one and start over again🙂
Luke said:
Leave some for the rest of us!😀
I don't find large C after a regulator to be hugely beneficial.
I tried the Bobwire approach once and put 1000uF everywhere (CD63) and then a more Thorsten-like approach on my CD-67SE. The 63 is in storage, the 67SE is listened to. I also have a stock 63 for reference.
It's just as easy to screw up these players soundwise as it is to make them better!
Luke said:
No, they mainly do valve stuff. If anyone can tell me where I can buy a top-quality frame transformer in the range of ~400va at 20vac x2 please tell me.
Luke said:
Interesting. Certainly this effect can happen with power amplifiers too. It can be improved by adding a "snubber" network across the large caps. I somehow don't think this would make the required changes for you though. What you really need are more transformers. This makes the bass something special in a CD63ki. I'm sure it will have the same effect in a '67.
I also think without reducing the psu noise and jitter in the standard player you'll never hear correct bass.
Furthermore I found the bass was very weighty but had terrible timing until I put the player on oak cones (three). This was my first mod and one of the very best.
Simon
I also find it beneficial to keep the digital caps small. The best sound I could get was with 47uF 25v Black Gate PK. Unfortunately, I can't find a supplier of them anymore🙁 . I think they're discontinued.
I had pretty good results with 100uF os-cons, ZL's etc though.
BTW, can anyone tell me why I have to switch my cd67 on, then off, then on again before it'll work please?
Lee.
I had pretty good results with 100uF os-cons, ZL's etc though.
BTW, can anyone tell me why I have to switch my cd67 on, then off, then on again before it'll work please?
Lee.
Yeah Im starting to think that too, but this is all quite new to me, problem is I take forever to decide on what to do where to mount it, so its a slow process. Think is though you get a feel for what has effects, what just sounds diff not better etc.
I think I will make some raygulators for now and see what diff it makes with say 100uF input low Z cap and say 220uF high Z crap cap output as TNT recommend, thats a nice easy to understand article on regulators, but they dont do a LM317 vs TL431, that would be intersting.
Simon,
Im starting to think more transformers too, but how big and where? Im really tight on space and dont know where to put them.
Also interested where to get oak cone feet, where are yours from?
QUOTE]I also find it beneficial to keep the digital caps small. The best sound I could get was with 47uF 25v Black Gate PK.[/QUOTE]
Thomo, thanks , sounds like a good thing to try then. Not sure why you need to reboot your player, what OS you running😀
happy modding people😎
Luke said:
As big as you can fit in. I'm using one for clock (and clock divider), one for DAC analogue and decoder analogue, and another for DAC and decoder digital. So that's 3 extra for now. I will be using a fourth for the servo chip. Mine are external. The bass gets deep and rock solid if you add these transformers. Of course this implies some separation of the 5v rails.
Oak cone feet were popularised by Russ Andrews Hi-Fi Accessories here in the UK. Various people will make them for you for much less. Not sure if postage to Aus will allow it to be economical but I could give you someone's e-mail address who made me (and also Brent) cones and other oak-turned parts.
Simon
Have you got a new clock fitted?...If so, your PSU is taking too long to start-up (maybe you have huge caps in there charging). Reduce the cap size, or better, power the clock PSU off the mains input before the switch so it runs all the time.
The switch on/off/on basically lets the clock get running before the rest needs it on the second start...
( I remember having exactly this problem with my old 63!)
(PS. Thomo - OT, but any news on the vishay caps?)
martin clark said:
Aaahhh, oops. Sorry for the delay, I just got caught up with the wedding and everything that goes with it and forgot! I will send them today + a couple extra as an apology.
Thanks for the advice, the superclock hasn't got its own psu (yet), it's running straight from a 10 or 12v link on the board.
update: I just switched on and the laser went crackers, and now it won't read the disc.
Ah - your clock relies on one of the existing rails. By the time this starts, and the voltage reference on the Superclock has come up, the decoder is already up and running and needs the clock. The laser/disc going out of control is the clue.
You could try running the clock off the raw DC rail before the reg for a faster start, but adding its own little PSU should be the guaranteed fix (and a good idea anyway)
[No worries about the caps BTW , just wanted to be sure they hadn't gone astray in the post that's all 🙂 ]
You could try running the clock off the raw DC rail before the reg for a faster start, but adding its own little PSU should be the guaranteed fix (and a good idea anyway)
[No worries about the caps BTW , just wanted to be sure they hadn't gone astray in the post that's all 🙂 ]
Thomo said:
Hi,
Had the same problem when I fitted an audiocom superclock to my 67. I sent it back and they fitted a different (smaller?) cap on the board which fixed the problem. Seems that certain circuits have too fire up in order (or together) and wrong combinations of caps can affect this.
Regards
Pete
Chivvyp said:
PS I've also had a situation where the toc wasn't read on a disc when I inserted it, closed the tray and pressed play. If i inserted a disc and pressed play to close the tray it worked. Never worked out why that would be but since I've put in seperated dedicated psu lines for clock and dac it's not been happening.
I think there must be something mystic going on!
Regards
Pete
Presumably tweaking this power-on reset circuit would be your solution? Part PST994D.
The time constant (to charge the cap to 63.2%) is 0.47 seconds.
The threshold is 4.2V which is 84% and it will take longer to reach this. Say 1 second. Increasing R or C should increase this window the system has to stabilise.
Try increasing CF03 from 4.7uF to 10uF to double this period, or 22uF to really make sure. I know it's a 63V part but they would only use that for convenience. It can only charge to 5V.
I'm sure I read somewhere that someone had a CD-63 that took half a minute to come on. I bet they mistakenly changed the cap for a bigger one during mods!
The time constant (to charge the cap to 63.2%) is 0.47 seconds.
The threshold is 4.2V which is 84% and it will take longer to reach this. Say 1 second. Increasing R or C should increase this window the system has to stabilise.
Try increasing CF03 from 4.7uF to 10uF to double this period, or 22uF to really make sure. I know it's a 63V part but they would only use that for convenience. It can only charge to 5V.
I'm sure I read somewhere that someone had a CD-63 that took half a minute to come on. I bet they mistakenly changed the cap for a bigger one during mods!
