Thanks for advice ray just mesured voltage at opamps got 1.4v so does that mean the dac ok6h5c said:
😕
Well, at least the DAC's analog output section is not screwed and the opamps are getting the correct DC levels. So any abnormal offset or current draw must be caused around the opamps, not by the DAC.
A complete test of the DAC is difficult, if you have a scope you can see if the three I2S signals and the clock are going in, and on pins 2 and 3 of the opamps you should see something that resembles an analog output signal.
But first I would solve the strange 12V problem.
- take the opamps out. Measure voltages at pins 4 and 8 to ground. Report.
- insert a 2~3k resistor in pins 4 and 8 of the IC sockets. Measure again at 4 and 8. Report.
Ray
A complete test of the DAC is difficult, if you have a scope you can see if the three I2S signals and the clock are going in, and on pins 2 and 3 of the opamps you should see something that resembles an analog output signal.
But first I would solve the strange 12V problem.
- take the opamps out. Measure voltages at pins 4 and 8 to ground. Report.
- insert a 2~3k resistor in pins 4 and 8 of the IC sockets. Measure again at 4 and 8. Report.
Ray
Update:
Just removed BGs fromCD05/06/12/13 fitted 100 ZAs also fitted 1000 RJH at 814 and disabled headphone
Sound has opened up, treble is cleaner, bass tighter and deeper.
Feeling happier now😀
Ian
Just removed BGs fromCD05/06/12/13 fitted 100 ZAs also fitted 1000 RJH at 814 and disabled headphone
Sound has opened up, treble is cleaner, bass tighter and deeper.
Feeling happier now😀
Ian
Hi fellas,
work is going on and I did not fried my IC. It all worked just fine. The servo reclocking mainly impressed me with nice bass, stong and clear. The level of detail and space also improved. And yes Ian, I find these players dull, need a lot of work to get it dynamic. My Onkyo and Philips were way faster in stock form and I still think in this state my CD-53 is still a bit dull. Maybe the output caps used (Yes Ray I removed my amp ones as they were no more needed... ), so these caps are not the best and I find the treble veiled and... dull. They are just here until I setup my DOS and real output caps. The fact I donwgraded from LME49720HA to LM4562 also get the player a bit less good.
Coax mod has been done. Voices sweet as my former CD-53 🙂
•> The clock divider dedicated regulator (LT1086) runs hot, very hot but not enough to burn me. I don't know if and when such IC needs a radiator, does it?
About the output caps, the amp combo in fact was the output caps of the CDP but just on the opposite side of the RCA. It worked very like a no-cap (even I the amp get even better without...) and just need the extra capacity for the DC and improved bass 🙂 As it will be very hard to fit in and I may get very close to the TX and PS parts I'm wondering if the channel near that will get degraded by some "noise" or such and the channel near the cabinet side get dead quiet and nicer, or there is no problem here?
Matthieu
nb: thank you to Matthew who gave me some left and free 6.8µF MKPs wich are very usefull right now... ! Also to my coax Santa Claus 🙂
work is going on and I did not fried my IC. It all worked just fine. The servo reclocking mainly impressed me with nice bass, stong and clear. The level of detail and space also improved. And yes Ian, I find these players dull, need a lot of work to get it dynamic. My Onkyo and Philips were way faster in stock form and I still think in this state my CD-53 is still a bit dull. Maybe the output caps used (Yes Ray I removed my amp ones as they were no more needed... ), so these caps are not the best and I find the treble veiled and... dull. They are just here until I setup my DOS and real output caps. The fact I donwgraded from LME49720HA to LM4562 also get the player a bit less good.
An externally hosted image should be here but it was not working when we last tested it.
Coax mod has been done. Voices sweet as my former CD-53 🙂
•> The clock divider dedicated regulator (LT1086) runs hot, very hot but not enough to burn me. I don't know if and when such IC needs a radiator, does it?
An externally hosted image should be here but it was not working when we last tested it.
About the output caps, the amp combo in fact was the output caps of the CDP but just on the opposite side of the RCA. It worked very like a no-cap (even I the amp get even better without...) and just need the extra capacity for the DC and improved bass 🙂 As it will be very hard to fit in and I may get very close to the TX and PS parts I'm wondering if the channel near that will get degraded by some "noise" or such and the channel near the cabinet side get dead quiet and nicer, or there is no problem here?
Matthieu
nb: thank you to Matthew who gave me some left and free 6.8µF MKPs wich are very usefull right now... ! Also to my coax Santa Claus 🙂
Hi Matthieu,
Nice work! It is true that a big cap will catch more noise that pollutes the signal going through it. Best thing is to find out which pin is the cap's outer foil and connect that to the output-side (= the opamps/DOS).
But why use 20 year old caps anyway? They will never sound as clear as new modern production ones. Also, a multiple cap cluster can form all kinds of different resonances.
If an IC gets too hot to touch, it's better to add a small heatsink. The IC itself can handle the heat, but the capacitors around it don't like it
. It decreases their lifespan.
Ray
Nice work! It is true that a big cap will catch more noise that pollutes the signal going through it. Best thing is to find out which pin is the cap's outer foil and connect that to the output-side (= the opamps/DOS).
But why use 20 year old caps anyway? They will never sound as clear as new modern production ones. Also, a multiple cap cluster can form all kinds of different resonances.
If an IC gets too hot to touch, it's better to add a small heatsink. The IC itself can handle the heat, but the capacitors around it don't like it
. It decreases their lifespan.Ray
Ray,
my experience has "seen" better sound (to my hear) with these caps than with new and famous ClarityCap or Audyn caps. I may go for the 1cm less diameter 6.8µF. I think it's a question of taste here 🙂
I've just found load of small radiators, they will live again!
Matthieu
my experience has "seen" better sound (to my hear) with these caps than with new and famous ClarityCap or Audyn caps. I may go for the 1cm less diameter 6.8µF. I think it's a question of taste here 🙂
I've just found load of small radiators, they will live again!
Matthieu
Of course, you are right. But in my humble opinion the Clarity caps and Audyn caps are not very special either, mostly they are standard MKP. These Russian caps give a very good value-for-money however, compared to those!
I did a blind test a while ago, comparing six coupling caps in a black box, with a rotary switch. It was very easy to separate the cr@p from the really good ones. The winners: AudioNote copper foil, good old Auricap MKP (!), Mundorf Supreme Silver/Oil 😀.
Losers: Jupiter Beeswax (yuk...), Russian PIO, Aura-T Teflon ($$$).
Regards,
Ray
I did a blind test a while ago, comparing six coupling caps in a black box, with a rotary switch. It was very easy to separate the cr@p from the really good ones. The winners: AudioNote copper foil, good old Auricap MKP (!), Mundorf Supreme Silver/Oil 😀.
Losers: Jupiter Beeswax (yuk...), Russian PIO, Aura-T Teflon ($$$).
Regards,
Ray
Let's have a look:
http://www.toutlehautparleur.com/mcap-supreme-silveroil/mundorf-supreme-so-680-p-2506.html
I should have said that money is the key 🙂 2 caps are over the full modded CD-53 I planned even with russians caps included!
In fact I never had good sound with only one PIO, maybe you do with such crazy priced caps but when you get the right cheap combo of PIO it does music.
I was also willing to have a try on Obbligato caps but price again...
Talking of rotary switch I was wondering if a stepped attenuator with resistors is a good upgrade for an amp... but that's not the place 😉
Matthieu
http://www.toutlehautparleur.com/mcap-supreme-silveroil/mundorf-supreme-so-680-p-2506.html
I should have said that money is the key 🙂 2 caps are over the full modded CD-53 I planned even with russians caps included!
In fact I never had good sound with only one PIO, maybe you do with such crazy priced caps but when you get the right cheap combo of PIO it does music.
I was also willing to have a try on Obbligato caps but price again...
Talking of rotary switch I was wondering if a stepped attenuator with resistors is a good upgrade for an amp... but that's not the place 😉
Matthieu
I agree, that's why I wrote the Russians are good value for money. That price is ridiculous, that's why I used the BG-Nx in the DOS...
I can ship some for you from Holland. Luckily, my tubeamp needs only 0,47uF! Soundwise, these caps are superior!
Ray
I can ship some for you from Holland. Luckily, my tubeamp needs only 0,47uF! Soundwise, these caps are superior!
Ray
Hi MatthieuMalefoda said:
Very good job !
I am very pleased using 4.7u obbligato + 100nF russian FT-3 Teflon as output caps. (This is the best combination so far)
PS: I did never used Auricap MKP... maybe these are even better.
Ricardo
Hi Ricardo,
well right now I'll use what I have and that should sound very good already and keep my budget tought player in.
Anyway I may try some Obbligato in a Rotel RDC1072 soon between the DAC and op amps, I may also try to bypass them with my left 0.022 Teflon.
Time to build my DOS!
well right now I'll use what I have and that should sound very good already and keep my budget tought player in.
Anyway I may try some Obbligato in a Rotel RDC1072 soon between the DAC and op amps, I may also try to bypass them with my left 0.022 Teflon.
Time to build my DOS!
DOS
Hello All,
I have just completed a swapout in my original DOS replacing the standard 7812 and 7912 regs with low noise DEXA regs. I also moved all components to a new board with bigger tracks.
The low noise regs are the real cats meow. As always when you remove noise from an audio circuit, music appears with much more low level information and detail resulting in bigger and harmonically richer sound, on every disc.
Just thought I'd pass this along.
Steve
Hello All,
I have just completed a swapout in my original DOS replacing the standard 7812 and 7912 regs with low noise DEXA regs. I also moved all components to a new board with bigger tracks.
The low noise regs are the real cats meow. As always when you remove noise from an audio circuit, music appears with much more low level information and detail resulting in bigger and harmonically richer sound, on every disc.
Just thought I'd pass this along.
Steve
rowemeister said:
Including myself as my other Marantz player with a DOS has the same low noise DEXA regs. I'm just catching up on the original.
My original DOS has different from standard parts in the low pass filter, and I think I will change the second DOS to these same parts, Rel RTE polystyrene caps and film resistors.
Ray's DOS is the best thing that has ever happened to these Marantz players!!!!!!
Well, I wonder where my LM317/337 ( known here as Raygs ) will bring my DOS, hope it's enough until Teddyregs... I'll try my best to avoid one cap and bring theses regs close to the DOS...
About dedicated 5V, seems everywhere it's fed with an RC low pass filter, is it the case or it's just an R to "separate" ps and C to keep some gas under the pedal? In first case it may be wise to feed the new 5V through the R.
When/if I supply 5V via a LT1086 5V wich is fed by the player TX then I'll ground it to the player, but what if I use a dedicated TX? I may cut the PCB trace and link ground to the TX ground only?
You may tell me what you think of this:
a 7VA TX and a LT1086 adjustable for the DAC digital, another LT1086 fixed 5V for the decoder
a 1.6VA for each analog side (AVdd1/AVdd2 and AVdd3/AVdd4) with LM317 so 3.2VA for the analog
a 1VA TX for Clock ref on LT1086 5V
Matthieu
About dedicated 5V, seems everywhere it's fed with an RC low pass filter, is it the case or it's just an R to "separate" ps and C to keep some gas under the pedal? In first case it may be wise to feed the new 5V through the R.
When/if I supply 5V via a LT1086 5V wich is fed by the player TX then I'll ground it to the player, but what if I use a dedicated TX? I may cut the PCB trace and link ground to the TX ground only?
You may tell me what you think of this:
a 7VA TX and a LT1086 adjustable for the DAC digital, another LT1086 fixed 5V for the decoder
a 1.6VA for each analog side (AVdd1/AVdd2 and AVdd3/AVdd4) with LM317 so 3.2VA for the analog
a 1VA TX for Clock ref on LT1086 5V
Matthieu
The R/C filters are mainly used if multiple IC's or power-pins are fed from one regulator, like in the CD63/67 players. If you use a dedicated regulator for a power-pin, you can leave out the R and just use a cap at the output of the regulator, and, if it is not close to the IC, another cap directly on the power-pin.
If you use a separate TX and regulator, only connect the ground of the player to the output-side of the dedicated PSU, just as you would connect the plus. Make the ground connection near the IC it is powering. Don't cut any traces, the circuit that is powered separately still needs a ground connection to the rest of the player.
What you should avoid is to make double ground connections, for example: connect plus and ground of a new PSU near the DAC IC, AND connect ground of that PSU's buffer cap (or the TX centre tap) to the player's ground also. Then you have created a nice ground-loop
.
Regards,
Ray
If you use a separate TX and regulator, only connect the ground of the player to the output-side of the dedicated PSU, just as you would connect the plus. Make the ground connection near the IC it is powering. Don't cut any traces, the circuit that is powered separately still needs a ground connection to the rest of the player.
What you should avoid is to make double ground connections, for example: connect plus and ground of a new PSU near the DAC IC, AND connect ground of that PSU's buffer cap (or the TX centre tap) to the player's ground also. Then you have created a nice ground-loop
.Regards,
Ray