Yes, that's correct. is not a hiss or Hum, sounds like you say. Yes I have one oscilloscope ( USB stuff, still in the box, but I think I can manage it)
Disconnect one phono channel from B+ first, listen only to one, anything changes regarding background noise? I see common B+in and GND paths in the reg's PCB and could be upsetting something. Again, what is the gain of your preamp? How is the volume at 12 O' clock? Having more to give or already 'too loud'?
P.S. Make sure that your PCscope can take that much DC as the regs's output. Those things are not like standalone scopes. If it takes it in its spec, you must see a thin straight line for reg's out. If its thick and by dropping microsecs you can even see a pattern, then its woosh by oscillation. Give me those bias voltages meantime.
P.S. Make sure that your PCscope can take that much DC as the regs's output. Those things are not like standalone scopes. If it takes it in its spec, you must see a thin straight line for reg's out. If its thick and by dropping microsecs you can even see a pattern, then its woosh by oscillation. Give me those bias voltages meantime.
Mine is 56db gain, I already try that, only one, two, disconnected from turntable, always the same. Both sounds exactly the same.
It's normal onthis shunts to take several seconds ( at least 10 sec) to get the final voltage ?
At 12 O'clock it's loud (i'm talking about the music, very similar to a cd)
It's normal onthis shunts to take several seconds ( at least 10 sec) to get the final voltage ?
At 12 O'clock it's loud (i'm talking about the music, very similar to a cd)
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Not from turntable, from power I said. Yes its normal. Its the 1000uF cap charging up on CCS's current. Your gain seems right. You got some bug somewhere. We need data. Is there any possibility you mix power ground near first stage's ground?
P.S. If this debugging proves difficult to you, make a quick LM317 supply and see if it has the same grunge. If yes, the bug is in the phono boards, if no, the bug is in the regs board.
P.S. If this debugging proves difficult to you, make a quick LM317 supply and see if it has the same grunge. If yes, the bug is in the phono boards, if no, the bug is in the regs board.
D1-D4 ground same path with first stage's source trimmer and cart's input load. Not best. One is cascode's bias (psu), the other is signal. I never do it that way but it may be benign enough. Either look in your power lines with your scope, or do the LM317 test. Check supply is clean in other words. If it is clean, then your phono boards have a ground bug. Else we find something untoward with the voltages I asked you for.
Yes; I gonna do that, meanwhile if I get the fault board I will measure it to post the results.
Sorry I send you the wrong PCB
I was ref to this
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Post #3949
@NPower
In your pcb I don't like IN gnd + RL gnd not referred with thier own track to star gnd. If you connect them to D4 gnd and R2V gnd, you mix up Signal gnd and Power gnd. Not good at all.
Take example from OUT gnd and R8 gnd: correct routing.
Plenty of space to fix this problem....
As already pointed out when you asked our opinion about your layout..... Disconnect RL gnd side and IN gnd, connect them togheter and then to the star gnd with a piece of wire.
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Hi Salas, compared vs measures gived with the cart I not see any change, very flat & a little bit upper highs increased, congratulations because sounds like measured
More DL103R info
Since there was discussion here about the real useful Denon compliance spec, that's how you can be sure: I run a high resolution FFT and the 103R gave 8.3Hz precisely on the Mission 774. The suspension is new but run in. It has 2 long aluminum screws with no nuts and a small aluminum DIY finger lift. I attach a picture. Make your assumptions and derive the compliance. Oh, don't forget to add a ton of dust in the moving mass calculations.
Since there was discussion here about the real useful Denon compliance spec, that's how you can be sure: I run a high resolution FFT and the 103R gave 8.3Hz precisely on the Mission 774. The suspension is new but run in. It has 2 long aluminum screws with no nuts and a small aluminum DIY finger lift. I attach a picture. Make your assumptions and derive the compliance. Oh, don't forget to add a ton of dust in the moving mass calculations.
Attachments
I got 25x10-6cm/dyne for Mission effective mass of 5.5g, Denon 103r mass of 8.5g and 0.5g screws + dust.
Can this be correct ?.
How does it feel to touch the cart tip with a light finger compared with a "normal" MM feel ?
I am used to the stifness of the B&O MMC 20EN that has a 30 compliance and it is quite easy to move the cantilever with a light finger.
Can this be correct ?.
How does it feel to touch the cart tip with a light finger compared with a "normal" MM feel ?I am used to the stifness of the B&O MMC 20EN that has a 30 compliance and it is quite easy to move the cantilever with a light finger.
Yes. If you can say the extra finger lift is 1-1.5 gram added, then 23cu is bottom number. Lets settle on 24cu give or take. Since this is measurement and math, the Denon spec question is surely answered in my book. In the 103R's case there is a multiplier of roughly 4-5 to keep in mind for the way the company measures and specs. I see many people not sure about what arm to match, asking on forums, so I hope we gave a firm account of the situation here.
I would say is double stiff on finger feel than Stanton 881S I had once. But this one is needing a bit of a firmer push because it is meant to track at 2.5g down force. Has low static compliance but medium dynamic compliance in other words.
I would say is double stiff on finger feel than Stanton 881S I had once. But this one is needing a bit of a firmer push because it is meant to track at 2.5g down force. Has low static compliance but medium dynamic compliance in other words.
Hello Salas
Today I only had one hour to play with this, so, I built another PSU with a TL783 ( only that one on mine stuff ) and I tried one channel at a time.
Ok , the problem is on the phono boards, same noise, maybe a little bit louder.
Now I think it's time to hack the PCB's, if I get some time tomorrow I will measure one PCB and I will post that.
By the way , what a huge difference in sound quality with the shunt's, a friend of mine was with me listening and said something like this with the TL783 " why the sound becomes so slow". I don't know the meaning of this, but for my hears is a huge difference.
Hello Massimo
post#4092
At that time I had already the PCB's done, so I decide to give them a try
As soon I measure the PCB I will perform your mod ( I will keep one phono PCB for ref)
Since there was discussion here about the real useful Denon compliance spec, that's how you can be sure: I run a high resolution FFT and the 103R gave 8.3Hz precisely on the Mission 774. The suspension is new but run in. It has 2 long aluminum screws with no nuts and a small aluminum DIY finger lift. I attach a picture. Make your assumptions and derive the compliance. Oh, don't forget to add a ton of dust in the moving mass calculations.
Small aluminum DIY finger lift, a ton of dust & Polyolefin heat shrink surely change the FS
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Hello Salas
Today I only had one hour to play with this, so, I built another PSU with a TL783 ( only that one on mine stuff ) and I tried one channel at a time.
Ok , the problem is on the phono boards, same noise, maybe a little bit louder.
Now I think it's time to hack the PCB's, if I get some time tomorrow I will measure one PCB and I will post that.
By the way , what a huge difference in sound quality with the shunt's, a friend of mine was with me listening and said something like this with the TL783 " why the sound becomes so slow". I don't know the meaning of this, but for my hears is a huge difference.
Hello Massimo
post#4092
At that time I had already the PCB's done, so I decide to give them a try
As soon I measure the PCB I will perform your mod ( I will keep one phono PCB for ref)
Now you know where to look for the bug, good luck & let us know.