It'll take the voltage if the caps are rated. You'll have to describe how you like the sound. Keantoken mentioned earlier that it might sound better with a bit less voltage. But I'm running higher than everyone else and it sounds great, so I'm not sure how important it even happens to be.
The transistors see a bit less than a 4th of the voltage (18/4=4.5 so a bit less than 4.5v). I think it might be better to have this headroom with some sources. My phono preamp claims up to 9v.
The transistors see a bit less than a 4th of the voltage (18/4=4.5 so a bit less than 4.5v). I think it might be better to have this headroom with some sources. My phono preamp claims up to 9v.
as I am going to use it in front of a passive RIAA filter, it's input impedance will affect the EQ curve.
What is the input impedance of the Kuart ?
What is the input impedance of the Kuart ?
100k when you use the BOM I provide, but some schematics show 10k input. It also has an input capacitance of about 18pF.
Hi Kean
but what if I use a 1meg ohm input resistor ? Does it work ? And what would be input impedance in that case ?
but what if I use a 1meg ohm input resistor ? Does it work ? And what would be input impedance in that case ?
With a 1Mohm input resistor input impedance would be around 1Mohm, input capacitance would not change.
Very good.
This is crucial info that I need to calc the RIAA filter.
now about output transistor current, can I raise R6 to 3k ?
This is crucial info that I need to calc the RIAA filter.
now about output transistor current, can I raise R6 to 3k ?
The DC trim resistor shunts the input resistor, so for 1Mohm input impedance you actually want to use a 1.5Mohm input resistor.
Hello everyone
I realized the Kuartlotron there is already a lot of time and this buffer is a small jewel. After some requests I took again my printed circuit design with a better placement and a plan of mass which proved however useless.
If the request is made I will be able to post the manufacturing files.
Regard's
I realized the Kuartlotron there is already a lot of time and this buffer is a small jewel. After some requests I took again my printed circuit design with a better placement and a plan of mass which proved however useless.
If the request is made I will be able to post the manufacturing files.
Regard's
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I have made an active 3 way active crossover with this buffer and I like it very very much. I even tried to drive the xo with this buffer. Probably the load is too much for the buffer since an AD815 based buffer gave me a much better slam and control. Unfortunatly the AD815 hasn't the magic and rightness of the Kuartlotron. Has anyone tried to add one more stage (BD139/140) to add muscles to this beautifull buffer?
Is this what you were doing? Notice the bootstrap is taken before the 47R resistor and there is no input shunt resistor (input must be DC coupled). You could also remove the 47R resistor entirely, it is there to help with cables.
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