I believe you are talking about the ground connection of the secondaries. I don't think you need to earth this to the PCB or the casing. when you have finished with the 5V regulator just fix the +5V to the DAC and connect the 0V to the PCB's common ground.
I used the star point near C813 negative terminal as my gnd point for everything. Can get a bit busy tho!!
Hi UV101,
I am hearing a kind of distortion after did the direct coupling of output. Initially I didnt hear this kind of distortion for last 2 days. Can you please tell me what will happen if DC go into amp and speaker? What should be the value if i measure DC?
Thanks
Badri
Thanks guys. The output of each of my 5v regulators is currently wired to both terminals of a 470uF local decoupling capacitor close to the chip. It sounds as though I can leave those connections in place until I upgrade my regs to lower noise types.
Just searched the forum for info on badrisuper's question and saw that Brent had 22mV/24mV DC offset and that went down to 2mV per channel when he moved to a star earthing scheme (for his regs?)
@badrisuper - the DC should measure as close to zero as possible. I have about 30mV offset per channel at the speaker terminals of my amplifier, which is a little on the high side. Depending on your amp/pre-amp, any DC present at the output of your player could get amplified my the same amount as the music signal. In the short term this could result in distortion and popping of the speakers, but it could also fry your voice coils and/or your amp. Did you measure it before you hooked it up?
Just searched the forum for info on badrisuper's question and saw that Brent had 22mV/24mV DC offset and that went down to 2mV per channel when he moved to a star earthing scheme (for his regs?)
@badrisuper - the DC should measure as close to zero as possible. I have about 30mV offset per channel at the speaker terminals of my amplifier, which is a little on the high side. Depending on your amp/pre-amp, any DC present at the output of your player could get amplified my the same amount as the music signal. In the short term this could result in distortion and popping of the speakers, but it could also fry your voice coils and/or your amp. Did you measure it before you hooked it up?
Mine are wired to the original IEC socket ground, but I find I get a fuller sound if I also don't use the internal insulator rings on the RCAs and screw them nice and tight to the chassis.
Take gnd from the original point that fed the output phonos. Where are you taking gnd for now? This could be the reason for distorted output??
For me at the speaker terminals I got 10mV DC on the Right speaker and 20mV on the Left speaker irrespective of volume setting of my amplifier and with or without the CD63 being turned on/off. It seems that the amplifier's input has built-in DC blocking capacitors. As to the CD63 RCA output, the measurement are both just less than 30mV DC. I did not hear any distortions at all.
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I didnt take the ground. Can you please tell me the position number fromt he scematic if it is there?
Thanks
Badri
Thanks
Badri
Seriously, if you cannot identify the original output gnd connection, you really shouldn't be poking around in the player.
Why don't you have a look and the PCB and point it out to me and then I'll help!!!!
Why don't you have a look and the PCB and point it out to me and then I'll help!!!!
RCA! The RCA socket ground! Not the IEC. OMG 😱
@badrisuper Hint: The RCA sockets that you removed only had two connections per channel - signal and ground. You've already connected one of them.
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Basic electronic theory is a help before you decide to try to modify these players we are all here to help,All of us started somewhere.
alan
alan
Thanks UV101. Please see the picture. Is it right? And I did read the DC, in right channel 14.2 and in left channel 33.8. Any suggestions.
Thanks
Badri
Attachments
Get a pair of good quality output caps such as Mundorf Silver/Oil 2.2uF - 4.7uF and run that signal wire through them. I got a matched pair of 3.3uF from Parts Connexion. They will block the DC for you.
Thanks Ben, Can you please post pictures of yours. I have K71 Russian Cap 1.2uf value. Is that enough?
Thanks
Badri
I don't have a pic of them to hand, I'm afraid. They're axial caps. The exact value required is based on the input impedance of your amp and desired low frequency rolloff. You can calculate the value you want here: Coupling Capacitor Calculator by V-Cap
My guess is your Russian caps will probably work just fine.
My guess is your Russian caps will probably work just fine.
Thanks Ben. Now the distortion gone. And I used Russian capacitor. Not bad, bass is controlled and very good but i feel like i it is little slow. I have to find a suitable cap. Any Suggestion.
Thanks
Badri
Cool. Further to my previous post, here's a link to a well-regarded output cap:
Mundorf Silver/Oil Series Film Capacitors
It's probably best to get a value between 2.2uF and 4.7uF. I personally chose 3.3uF.
By the way, you might want to let the Russian caps settle in a bit before you cast definitive judgement.
In other news, I fitted the first of my dual 15v supplies this evening. It's tested and ready to hook up to the DAC analogue regs tomorrow.
Mundorf Silver/Oil Series Film Capacitors
It's probably best to get a value between 2.2uF and 4.7uF. I personally chose 3.3uF.
By the way, you might want to let the Russian caps settle in a bit before you cast definitive judgement.
In other news, I fitted the first of my dual 15v supplies this evening. It's tested and ready to hook up to the DAC analogue regs tomorrow.
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I've not seen one of these with DC on the output. Something doesn't sound right.
Cap wise, I've not used lower than 4.7uF althought I know Brent was running 2.2uF with his dos. I believe a lower value can start to effect the bass. If you are buying new caps, I'd go for 4.7uF but you may be ok with 3.3uF as Ben suggested.
When will you have a listen Ben?????
Cap wise, I've not used lower than 4.7uF althought I know Brent was running 2.2uF with his dos. I believe a lower value can start to effect the bass. If you are buying new caps, I'd go for 4.7uF but you may be ok with 3.3uF as Ben suggested.
When will you have a listen Ben?????