Time for a cheeky modding pic 
The first is my new SAA7220 power supply. The second is the whole player and supplies with a new-old cap being formed ready for the decoder supply. It is singing now but still not smooth enough (NE5534 aren't so hot in this regard!)
The first is my new SAA7220 power supply. The second is the whole player and supplies with a new-old cap being formed ready for the decoder supply. It is singing now but still not smooth enough (NE5534 aren't so hot in this regard!)
Attachments
Thanks Matthieu. The RCAs aren't quite in those holes.
Simon
ps - got about 100,000uF of capacitance in this CD player now. In itself it's probably not so important but with the multiple transformers and good regs I'm getting some nice chunky bass and top draw dynamic swings.
Simon
ps - got about 100,000uF of capacitance in this CD player now. In itself it's probably not so important but with the multiple transformers and good regs I'm getting some nice chunky bass and top draw dynamic swings.
Attachments
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Had some time to look at the problem with my CD160 yesterday.
Odd, switched it on and it worked again. Powered off and on and it was dead again.
Replaced the A dac with the original non A one and it's back up and running again.
Hopefully it was just a dodgy dac chip rather than some of the changes that I'd made causing the problem.
Pete
Odd, switched it on and it worked again. Powered off and on and it was dead again.
Replaced the A dac with the original non A one and it's back up and running again.
Hopefully it was just a dodgy dac chip rather than some of the changes that I'd made causing the problem.
Pete
Hi,
as clocking problems are appliable to this player and all SAA/TDA1541 teams:
my attempt to reclock the TDA on is own failed. In any position i got silence or slight withe noise.
Before:
I have a Flea, powered by a dedicated PSU, from only one R at the XO's output pin, 2 wires, one for the Decoder and one for the Filter, then the ground to the Filter's ground.
Work like clockwork (!).
Now:
Then I fitted a LM317, a +10V from the player PSU, ground to a local ground passing by. Shows a solid 4.98V.
A FlipFlip 74HC74 is fed by a pair of wires, ground and +5V from that reg, a 10µF 35V and a 100nF X7R between the 7 & 14 pins.
A new R (100R; PRP), is set at the XO's output pin, via a coax, soldered at the Clock pin of the flipflip, pin 3.
Another coax goes from pin 5, then 6, to pin 2,
I've tried it with Q and Q_, with the RC 1K/10pF wich works fine with SAA7220 OEM data lines, 100R, always with pins 4 & 2 linked on PCB.
Don't know what i've missed, maybe something obvious?
I've seen some BCK from the SAA7220 wired to the Data of the Flipflop, a must be done?
Ground and PSU problem? Sync problem? Speed of start problem? Flea feeds problem?
Before I go back I'll be happy if any things to check guys. Thanks!
When I think that was the last mod before amp/speakers works...
Matthieu
as clocking problems are appliable to this player and all SAA/TDA1541 teams:
my attempt to reclock the TDA on is own failed. In any position i got silence or slight withe noise.
Before:
I have a Flea, powered by a dedicated PSU, from only one R at the XO's output pin, 2 wires, one for the Decoder and one for the Filter, then the ground to the Filter's ground.
Work like clockwork (!).
Now:
Then I fitted a LM317, a +10V from the player PSU, ground to a local ground passing by. Shows a solid 4.98V.
A FlipFlip 74HC74 is fed by a pair of wires, ground and +5V from that reg, a 10µF 35V and a 100nF X7R between the 7 & 14 pins.
A new R (100R; PRP), is set at the XO's output pin, via a coax, soldered at the Clock pin of the flipflip, pin 3.
Another coax goes from pin 5, then 6, to pin 2,
I've tried it with Q and Q_, with the RC 1K/10pF wich works fine with SAA7220 OEM data lines, 100R, always with pins 4 & 2 linked on PCB.
Don't know what i've missed, maybe something obvious?
I've seen some BCK from the SAA7220 wired to the Data of the Flipflop, a must be done?
Ground and PSU problem? Sync problem? Speed of start problem? Flea feeds problem?
Before I go back I'll be happy if any things to check guys. Thanks!
When I think that was the last mod before amp/speakers works...
Matthieu
Output from the DAC is a current not a voltage, it feeds a virtual earth created by the first op amp, so you won't see any significant voltage at this point.
Thanks for the explanation, although I find it quite hard to get my round round
(Arcam Alpha mods - http://www.diyaudio.com/forums/digital-source/167068-arcam-alpha-mods.html )
Simon
(Arcam Alpha mods - http://www.diyaudio.com/forums/digital-source/167068-arcam-alpha-mods.html )
Simon
Hi Pete,
You've probably got a problem with the DEM clock. The non-A dac has the capacitor that makes the DEM clock run built in. The A type hasn't got that capacitor, you need to add it between pin 16 and 17, it is a 470pF capacitor.
It should work OK when you add that cap.
Best regards
Joris
Matthieu,
It's very normal, as Lee says the decoder and digital filter use lots of current and it makes the voltage regs very warm indeed. Try running a little class A output stage in there too...
It's very, very warm in the UK today, it won't last!! I'm taking advantage and have been doing woodwork in the garden, speaker stuff
Simon
It's very normal, as Lee says the decoder and digital filter use lots of current and it makes the voltage regs very warm indeed. Try running a little class A output stage in there too...
It's very, very warm in the UK today, it won't last!! I'm taking advantage and have been doing woodwork in the garden, speaker stuff
Simon
Pete you could test with a 470pF cap although according to EC there are several other values that will result in a better DEM lock!!
You could go the whole hog and do the full DEM reclock!!!
** As Joris correctly pointed out, most (if not all) commercial implimentations use a 470pF
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Hi, I don't think that was the problem.
Although the CD160 is a non A machine it does have a 680p cap in that postion as standard.
It had been working ok for several weeks with the A dac, I guess it wouldn't have worked at all without that cap in place.
Regards
Pete
I'm going crazy,
seems I'm the only one can't get the TDA1541 reclocked.
Help! Promise will wash my theeth after having goat cheese and wil get more humble!
http://www.diyaudio.com/forums/digi...ero-oversampling-cd-player-2.html#post2196146
='(
It's so nice with it ( striking bass, dynamic, detail... all!) I'll be the happiest man on earth with that terrific mod fixed!
Matthieu
seems I'm the only one can't get the TDA1541 reclocked.
Help! Promise will wash my theeth after having goat cheese and wil get more humble!
http://www.diyaudio.com/forums/digi...ero-oversampling-cd-player-2.html#post2196146
='(
It's so nice with it ( striking bass, dynamic, detail... all!) I'll be the happiest man on earth with that terrific mod fixed!
Matthieu
Hi Simon,
for me this was as huge as the SAA7220 dedicated reg: the 2 best mods! When it works...
Well it's the pin 2 still linked to 4 by the oem's pcb trace. No way to restart the player this evening :'( Just hope in worst case that I'ne not done any harm to the TDA! I still can undo that last mode, and get back my great player... I want the " greater " version ! That kicking bass...
Wondering about faster logic with VHC ICs, or playing with "clear" & "reset"via a switch or such... even in reclocking the whole I2S!
Matthieu.
for me this was as huge as the SAA7220 dedicated reg: the 2 best mods! When it works...
Well it's the pin 2 still linked to 4 by the oem's pcb trace. No way to restart the player this evening :'( Just hope in worst case that I'ne not done any harm to the TDA! I still can undo that last mode, and get back my great player... I want the " greater " version ! That kicking bass...
Wondering about faster logic with VHC ICs, or playing with "clear" & "reset"via a switch or such... even in reclocking the whole I2S!
Matthieu.