Re: Re: Statistical question for all
Just for fun I did a statistics analysis of the data using Minitab.
The universe is 57 jfet.
As you can see, the distribution is almost "normal" so Median is very similar to the Mean.
8.5mA seems very good indeed.
Ricardo
Hi SalasRCruz said:
Just for fun I did a statistics analysis of the data using Minitab.
The universe is 57 jfet.
As you can see, the distribution is almost "normal" so Median is very similar to the Mean.
8.5mA seems very good indeed.
Ricardo
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salas said:
I see that you are very expert in voicing. Since we helped you to go fast in the ballpark, now play ball libero.
Thank you for the exceptional compliment but my knowledge is very limited compared with yours.
What I know about caps, I read in the net.....!!!
I am able to compute or calculate as other engineers do but I never studyed electronics in the university.
I am very gratefull for the information you give for free in the internet.
My vision is quite poor and my hands are not so steady so I can not solder 100pin chips, but nature gave me a very acute hearing.
I can really hear the differences after any mod, and after some years modding I am now understanding the effects of each component... and that is all.
I love learning, studying and verifying the results of the mods I do after a good planning.
Regards
Ricardo
PS: It seems the noises problem only appears after I do some soldering in the PCB... after some burning in, the noises disappear even if I switch the riaa on/off.
OK guys, those answers were very illuminating. I am preparing 3 standards. MM, HighMC 1mV, MC 0.5mV. First stage cascode. Those I will send to Kent, along with a Shunt with JFET enhanced transistor Vbe CCS and R6 mod (as Ikoflexer ended up). Three voltage values, same circuit. So anybody that wants to make the Simplistic NJFET RIAA & Simplistic Mosfet Shunt Reg, will not have to look for specific LEDS, calculate current with R1 etc. That will be a clear, specific, final resume sporting definite PCBs. Anybody new who will want to know for instance how non cascoded sounds and for what systems may be better, or wants LEDS, very low MC etc. will have to try a little and read the thread.
Hi Salas
Good work - Finally we will be able to understand the various options...
Today I received my FT-3 from Russia.
I noticed you replaced the C1 PIO by one of those Teflons.
Can I do the same ?
(I am using the obbligatos without any bypass)
I am searching for more detail and larger soundstage without loosing any mid freq presence and attack.
Ricardo
PS
Once again I am leaning in your experience.
Good work - Finally we will be able to understand the various options...
Today I received my FT-3 from Russia.
I noticed you replaced the C1 PIO by one of those Teflons.
Can I do the same ?
(I am using the obbligatos without any bypass)
I am searching for more detail and larger soundstage without loosing any mid freq presence and attack.
Ricardo
PS
Once again I am leaning in your experience.
What type of mundorf are you using ?nicoch46 said:
I use mundorf on signal path,
stannol free pb
kester 77 for hard work (big gnd, hair dryer helps a lot
WBT 4% silver 0.8mm..... I used it a lot in other mods (CDP, 101b etc) and only once had this issue before when I replaced the analog psu in the cdp. I believe it is my desoldering technique that causes the problem.
When I populated Lee´s board, it worked perfectly the first time. This happened because I replaced all resistors at the same time and did a mess.... padlifter is the apropriate name..
Do you mean you pre-heat the points before soldering ?
Ricardo
Rewarding work !!!!
Hi Salas
Today, while looking at my new FT-3, still lying on the bench and listening to my son´s comments about the "bilhas russas", the left channel started to puff at very low freq.... pooooor woofers...
So I decided to mod.
First I replaced Q5 (buffer jfet) and the annoing sounds persisted.
So I decided to clean up the board again.... still oscilating.
Finally I decided to probe (very tricky thing due to my newly aquired human handycaps) and found that R4 oscilated quite vividly from 12 to 8v... the other channel was steady at 10.5v.
Looked at the circuit and decided... Q2 have to go.
After replacing this one, the circuit stabilized in 50 sec......
FT-3 are in place and even from the beguinning I can say these are much better for this job replacing the PIO K40y on C1.
Better bass control and seemingly infinite extension on low freq.
No proheminense in the mids.
Sweet very integrated highs.
Now I will have to listen to all the records again...
Ricardo (Very happy... Very confortable... Very very...
)
Hi Salas
Today, while looking at my new FT-3, still lying on the bench and listening to my son´s comments about the "bilhas russas", the left channel started to puff at very low freq.... pooooor woofers...
So I decided to mod.
First I replaced Q5 (buffer jfet) and the annoing sounds persisted.
So I decided to clean up the board again.... still oscilating.
Finally I decided to probe (very tricky thing due to my newly aquired human handycaps) and found that R4 oscilated quite vividly from 12 to 8v... the other channel was steady at 10.5v.
Looked at the circuit and decided... Q2 have to go.
After replacing this one, the circuit stabilized in 50 sec......
FT-3 are in place and even from the beguinning I can say these are much better for this job replacing the PIO K40y on C1.
Better bass control and seemingly infinite extension on low freq.
No proheminense in the mids.
Sweet very integrated highs.
Now I will have to listen to all the records again...
Ricardo (Very happy... Very confortable... Very very...
)
Salas hi,
Yesterday I installed some Mundorf silver oil at the output and sound is even better. Of course I will give them some time to brake in. Also I installed the bypass capacitors recomended, an 100 nF SCR.
I have one question for you though. As you probably saw at the pictures, I use some russian KY40 capacitors for RIAA. The thing is when I measure them with my LCR meter, their D (dissipation) is around 0,00036 against to 0,00001 to some MKP. What do you think about that? Which capacitor would be the best choice for this place of the circuit?
Yesterday I installed some Mundorf silver oil at the output and sound is even better. Of course I will give them some time to brake in. Also I installed the bypass capacitors recomended, an 100 nF SCR.
I have one question for you though. As you probably saw at the pictures, I use some russian KY40 capacitors for RIAA. The thing is when I measure them with my LCR meter, their D (dissipation) is around 0,00036 against to 0,00001 to some MKP. What do you think about that? Which capacitor would be the best choice for this place of the circuit?