OK, the PS ground now goes to the binding post, and separate wires go from there to the boards. Noise gone
What do you mean by 10R/1W or CL60?
Happy that you succeeded
You can now reference GND to Earth through a 10R/1W or CL60 thermistor.
For this ou can also alternatively use a diode bridge, as mentionned in the Pearl II manual. It gives a safety connection in case there is a fault and a lot of current flowing through Ground.
May be it can help lower the noise floor, depends of the wholde setup. Just try it
Best,
nAr
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Got it. I also see that Fran recommended a 0.01uF cap for this.
Yes. 10 nF cap can help if you have some radio waves coming in, FM noises, etc ...
For best effect, use ceramic disc type, and mount it short, direct on the input RCAs
This cap is not necessary in all situations though
Best,
nAr
I happen to have a 10 ohm 1/4w resistor left over from another project. Is it necessary to use a 1W resistor?
It can "pass" more current without blowing in case of a problem, this is why a tad higher wattage than 1/4W is preferred. 1W, 2W, or 3W types are quite OK too
I'm still seeing some minor voltage instability on the left channel board. It will drift 20-30mv, then a small turn of the pot will cause a swing of 300mv. C7 is removed. Any other ideas?
Mark
This is by design; Wayne stated that in closed box offset would be more stable;
a rework of the design layout by coupling diff pair , output stage and according CCSs could make the offset more stable, with lower amplitude ( +/- 1 mV )
Best,
nAr
Sorry if this has been asked before.
I am thinking about building a few mc phono stages and the pearl is definitley at the top of my list.
I have noticed that the output capacitors are a 100nF Film and 22uF electrolitic.
I do not realy like to use eletrolitic caps as decoupling.
As I am building more than one I was wondering if there is a capacitor value that may do the lot at a compromise (Sallas Simplistic uses a 2.2uF for example)
I am thinking about using Mundorf or Obbligato so especialy for the Mundorf is big money
I understand that a smaller value capacitor efect the low frequency and maybe can help with rumble and record warp.
How is the output capacitor calculated for the Pearl 2?
For semplicity the next stage (volume and preamplifier have 10K impedence)
Tanks
I am thinking about building a few mc phono stages and the pearl is definitley at the top of my list.
I have noticed that the output capacitors are a 100nF Film and 22uF electrolitic.
I do not realy like to use eletrolitic caps as decoupling.
As I am building more than one I was wondering if there is a capacitor value that may do the lot at a compromise (Sallas Simplistic uses a 2.2uF for example)
I am thinking about using Mundorf or Obbligato so especialy for the Mundorf is big money
I understand that a smaller value capacitor efect the low frequency and maybe can help with rumble and record warp.
How is the output capacitor calculated for the Pearl 2?
For semplicity the next stage (volume and preamplifier have 10K impedence)
Tanks
Seems a neat solutionbksabath, I used a 22UF AEON cap from parts express. Bypassed with a Wima MKT1837.
I did not find the gain sufficient for a DL-103, so I put some step-ups in there. I like that much better.
Gain can also be increased by increasing feeback resistor value
55 dB seems a good match with low MCs
Best,
nAr
Tea-bag, what kind of step-ups did you use? And, how does the input to the Pearl look? I mean, what kind of loading is required for the step-ups? I'm also finding that the gain is a little lower than I want for the DL-103, even after the increasing the feedback resistor value. I guess both of us have lower gain in the rest of our system (using a B1 for the preamp, are you?).
Tanks Tea-Bag
I dig the Wima 1837 but i was wondering if getting rid of the electrolitic
and using a posh film may improve the sound
If I was going to make one Phono pre investing on same expensi capacitors for best performance would be not a problem.
I have 2.2uF Mundorf camming for Sallas Simplistic in and was wondering how the coupling output capacitors where calculated for the Pearl2
I suspect that the output capacitor would be of great influence on the sound signature
and by fitting a 1/10 of the reccomended value may not give the Pearl a fair chance.
I dig the Wima 1837 but i was wondering if getting rid of the electrolitic
and using a posh film may improve the sound
If I was going to make one Phono pre investing on same expensi capacitors for best performance would be not a problem.
I have 2.2uF Mundorf camming for Sallas Simplistic in and was wondering how the coupling output capacitors where calculated for the Pearl2
I suspect that the output capacitor would be of great influence on the sound signature
and by fitting a 1/10 of the reccomended value may not give the Pearl a fair chance.
Tanks Wayne being that 7hZ at -3dB is corect?
So not much of a compromise if I try Pearl 2 with this value and hig quality cap instead of electrolitic.
I am inclined to go for pumpkin and of the top of my head imput impedence should be hier than the 10K ball park figure so roll off be lower
Sorted
Tank you
So not much of a compromise if I try Pearl 2 with this value and hig quality cap instead of electrolitic.
I am inclined to go for pumpkin and of the top of my head imput impedence should be hier than the 10K ball park figure so roll off be lower
Sorted
Tank you
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