on the NA-5? the EC2 is negative of pin 12?
the NA-5 is a non latching, i thought the first polarity is the right one, which indicate pin 12 is negative
A project
Junior line; multi configurable fro different tubes
The THD vs level has a 0 dB = 2 volts
There is also the possibility to insert the pcb of tone control.
Two mwthod of bias: fixed and autobias, configurable
I prefer this configuration due the more detailed sound ( my opinion and some other people)
Junior line; multi configurable fro different tubes
The THD vs level has a 0 dB = 2 volts
There is also the possibility to insert the pcb of tone control.
Two mwthod of bias: fixed and autobias, configurable
I prefer this configuration due the more detailed sound ( my opinion and some other people)
Attachments
Thank you Koifarm
What is the voltage rating for 100nf at C1 and C11? 63V should be enough? Is the value of 100nf critical? What is the function of this capacitor ?
I notice the 400 V 10Uf output capacitor. Can i substitute for 4.7Uf , 250 V rating?
What is the voltage rating for 100nf at C1 and C11? 63V should be enough? Is the value of 100nf critical? What is the function of this capacitor ?
I notice the 400 V 10Uf output capacitor. Can i substitute for 4.7Uf , 250 V rating?
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Voltage rating C1/C11 should be minimal voltage drop(80/90V)over R5 but at warmup this voltage could be easy 150/200V. To be save use minimum voltage of anode supply(265v).
The upperstage is a active load. It is just a cathode follower. C1 and R6 are a high pass filter the crossover point should be below 20Hz.
The voltage of the output capacitor is the same story as C1.
The value can depend on the inputimpedance off the following stage. It is also a highpass filter.
You can calculate crossoverpoint by freq(hz) =1/(2*3.14*R(ohm)*C(F)).
10uf is good for low impedance like 2k
2.2uf is good for impedance like 10k
and you can use 0.22uf for 100k input impedance.
One thing if you choose capacity to low there is no bass. So do not go cheap.
The upperstage is a active load. It is just a cathode follower. C1 and R6 are a high pass filter the crossover point should be below 20Hz.
The voltage of the output capacitor is the same story as C1.
The value can depend on the inputimpedance off the following stage. It is also a highpass filter.
You can calculate crossoverpoint by freq(hz) =1/(2*3.14*R(ohm)*C(F)).
10uf is good for low impedance like 2k
2.2uf is good for impedance like 10k
and you can use 0.22uf for 100k input impedance.
One thing if you choose capacity to low there is no bass. So do not go cheap.
Koifarm, is your universal tube preamp good to be used as a buffer with a low impedance (1k8) Hypex UCD400oem?
Did you use a different tube buffer on your UCD400oem?
Thanks for support and for sharing with us your project 🙂
Did you use a different tube buffer on your UCD400oem?
Thanks for support and for sharing with us your project 🙂
Ok, very thanks for your answer.
May you share the gerber files of your tube preamplifier "Hypex oem version", with the 36pin headers, with schematic? Or maybe you have already published them in another Hypex dedicated topic, even if I don't think so.
Thanks again 🙂
May you share the gerber files of your tube preamplifier "Hypex oem version", with the 36pin headers, with schematic? Or maybe you have already published them in another Hypex dedicated topic, even if I don't think so.
Thanks again 🙂
Sorry,
this was more then a decade ago.
https://www.diyaudio.com/community/threads/hybrid-hypex-ucd.115388/page-4
No gerbers, only SE version.
It is not so difficult to make a adaper board for the pcb in this thread.
Or look here:
https://www.diyaudio.com/community/...urifi-1et400a-amps.379211/page-3#post-7046086
this was more then a decade ago.
https://www.diyaudio.com/community/threads/hybrid-hypex-ucd.115388/page-4
No gerbers, only SE version.
It is not so difficult to make a adaper board for the pcb in this thread.
Or look here:
https://www.diyaudio.com/community/...urifi-1et400a-amps.379211/page-3#post-7046086