With me here in the R. Macedonia tempeature was 34...38 degrees Celsius and the sun as much as you want!
Hi all !
Very good simple preamplifier with excellent sound and no one to try to develop and discuss a little with respect thereto!?
Cheers!!!
No, because here you have to build what everybody else is building. For example, make a preamp with a pentode, and a mosfet ccs. Then everybody will like it.
No, because here you have to build what everybody else is building. For example, make a preamp with a pentode, and a mosfet ccs. Then everybody will like it.
Please give your schematic with the preamplifier mention that with a pentode, and mosfet CCS?!
Cheers !
+1
Same thing applies to the tubes being used. If it ain't a mainstream tube, it ain't good enough... or so they say.. Much to the joy of those of us who like oddball tubes...
High-End preamplifier with 12AX7 (ECC83) !?
Hi all !!
If one is interested in making this a "High-End Preamplifier with 12AX7 (ECC83)", can give values of components to give the schematic!?
Cheers !!
P.S.
Podrav do zemjakot Goran B.
Zemjak ubav e ovj predzasiluvac so ECC83!! Mnogu interesen, definiran i prijaten zvuk za slusanje dava,...
Hi all !!
If one is interested in making this a "High-End Preamplifier with 12AX7 (ECC83)", can give values of components to give the schematic!?
Cheers !!
P.S.
Podrav do zemjakot Goran B.
Zemjak ubav e ovj predzasiluvac so ECC83!! Mnogu interesen, definiran i prijaten zvuk za slusanje dava,...
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Hi
Here they are:
R1=12k, R2=30k, R7=470k, R9=1M, R8=30k R10=100k, R11=2k7, R12=560k,
R13=100k, R14=1M, R15=1k5, R16=100k/o,5W, R17=1k/1W. Out P1=50k/log
all resistors with 1% metal film!!
C1=470nF/63V-MKP, C2=220nF/400V-MKP, C3=5p6/500V-stiroflex, C4=33pF, C5=220nF/400V-MKP
C6=3,3uF/100V-MKP, C7=100uF/350V, C8=100nF/400V.
Regards
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This is the frequency response of the complicated RC-network between the tube halves. There is practically no effect at the audio band.
What is it for, execpt attenuator ?
An externally hosted image should be here but it was not working when we last tested it.
What is it for, execpt attenuator ?
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The frequency response of which?
I do not understand, whose is this frequency response?
And where are the measurements of harmonics?
Well-filtered and stabilized DC-voltage Uf=2x6,3V/300mA
Well-filtred and stabilized DC-voltage Ua=+250 V/30mA!
For High-End preamplifier with 12AX7!!!
Regards !
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Sorry, I'm confused. In what sense of "high end" is this a high-end preamp? It uses high gain valves, but then attenuates much of the gain away. It has a relatively high (and variable) output impedance so cannot drive long cables. It has an equalisation network, for no apparent reason (except perhaps to compensate for stray capacitance in the high impedance attenuator?). It has to be high impedance because of the peculiar choice of valve. The only sense in which it might be considered 'high end' is that it is eccentric!
This kind of construction has better linearity due to local negative feedback at first stage. The gain can be reduced by increasing cathode resistor (now 5k6) if required.
The output inpedance is also much lower and constant compared to your circuit.
The output inpedance is also much lower and constant compared to your circuit.
An externally hosted image should be here but it was not working when we last tested it.
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