Yes thanks!
I'm trying to read up the Quasimoto thread. Wish there was more time in the day. I honestly don't know how most of you do it.
Salas, I asked earlier about a very low outout cart. What about 3.2mV? Would I be correct at 43dB.
Yes, you should be. 43db gain gives you 710mV output for the standard 5mV in ... so 450mV output for 3.2mV in.
450mV should be enough input to your preamp, unless it has very low gain.
Regards,
Andy
Finally... After having trouble with matching the led (the one from GB somehow didn't lit).
I can play the Tp1 and Tp2 in between 3.6 and 3.7.
But the drifting of Tp1 and TP2 is quite high (3.55 ~ 3.73) and It keep drifting on those value... is that normal??
I also have to increase the R3X to 11K (with 9K1 I always get 7.6V)
I can play the Tp1 and Tp2 in between 3.6 and 3.7.
But the drifting of Tp1 and TP2 is quite high (3.55 ~ 3.73) and It keep drifting on those value... is that normal??
I also have to increase the R3X to 11K (with 9K1 I always get 7.6V)
Did you give it enough time? Atleast half an hour is not unusual for stabilizing. If it doesnt there is a temp drift due to variating cooling/self heating.
I did measure it after 30 minutes... it seems that that the variation is started to steady (smaller drifting)...
BTW is it OK using R3X up to 11K? I can't adjust it if I follow the manual... everything is stable. I tried to connect it without case and got alot of hummm 😀
BTW is it OK using R3X up to 11K? I can't adjust it if I follow the manual... everything is stable. I tried to connect it without case and got alot of hummm 😀
It will change by small wind, an open door, or you changing instruments in contact. Box it in and put some probes on and leg them stay I'm sure it will stabilize.
If the mean average IDSS of K117GR fell lower in the kits then 11K is valid.
Drift will be there in MC two JFET builds. When just hovering around target center fairly when warmed up means good to go. Hum is a buid and wiring issue. Many said they could get very low hum with FSP even when naked but this does not apply to all environments and system groundings. Are the raw PSUs wired as the PDF's generic model?
I'm stil strugling wether or not leaving the gate stoppers away...I read a lot of differences in feedback.
I will follow classic Le pacific...with a 6,2mV cartridge output volume. Due to lowering the drain resistors (for a better output impedance)..I will losse some gain...but I don't see a problem. But what do you think is the best to do with the gate resistors?
I will follow classic Le pacific...with a 6,2mV cartridge output volume. Due to lowering the drain resistors (for a better output impedance)..I will losse some gain...but I don't see a problem. But what do you think is the best to do with the gate resistors?
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In my layout and gain structure missing them did not present problems. They are very detrimental regarding SNR of the head amp when entering MC area builds. If you can, do without. If its MM they are more tolerable. It takes practical research in every different preamp. It can tune in radio even.
Yes.. I use two JFET 369...
I'm got a quite stable Vrail at 30V (Tp1 & Tp2 3,5XX to 3,7XX)....
Still looking for decent chassis before upload the pic....
I'm gonna put my Jfet phono in the same case as my DCB1....hope this will work fine. So two toriods...and I really hope the "envirement" is quiet enough. In the pas I buided a opamp circuit (with good OPA-types)....even in a wooden enclusere....the result was "doable"....but these days we wouls like to build everything more decent 🙂
the output impedance of your jFET phono should be low enough that it does not need another Buffer to drive the cable from the TT to the volume control.
After trying so many position finally i can try without hum by putting transformer 25 cm from the board... Testing using DL-103 alu body revelaed that the phono really great...
Thank you Salas for providing us such a great design...
Thank you Salas for providing us such a great design...
Very good. Congratulations.
Yes... Definitely need a nice alu box...
As for TT... I searched for so long to get the rare vintage like that.. 🙂
I like L75S because the arm is heavy (easy setup for MC)... Unlike its brother (L75/L78), the arm is rather nice looking...