Good news, AudioXpress will feature LuminAria in this week's Audio Voice e-newsletter.
That means you'll be able to read and download the original article here:
You Can DIY!: LuminAria SIT Preamplifier | audioXpress
I'd like to thank the editors at AudioXpress for making this available and I hope you will be encouraged to show your support by subscribing.
I hope to have a new SIT preamp article for you this winter.
Mike
That means you'll be able to read and download the original article here:
You Can DIY!: LuminAria SIT Preamplifier | audioXpress
I'd like to thank the editors at AudioXpress for making this available and I hope you will be encouraged to show your support by subscribing.
I hope to have a new SIT preamp article for you this winter.
Mike
Last edited:
You're certainly welcome. My pleasure
When I did this, it was meant to be a "show the work (design and calculations)" piece, so there are some things I ultimately did differently for my own copy. The main difference being fixed bias, which Tim has done here as well to nice effect.
Also, just in case it comes up. The PCB's shown in the article have never been publicly available. They were special prototype boards I used that had all kinds of extra jumpers and pads so I could try a lot of different stuff, so I don't intend to release them. Maybe I'll do one for the next one...
When I did this, it was meant to be a "show the work (design and calculations)" piece, so there are some things I ultimately did differently for my own copy. The main difference being fixed bias, which Tim has done here as well to nice effect.
Also, just in case it comes up. The PCB's shown in the article have never been publicly available. They were special prototype boards I used that had all kinds of extra jumpers and pads so I could try a lot of different stuff, so I don't intend to release them. Maybe I'll do one for the next one...
You're welcome. Glad you enjoyed it. I'll check on that. It's been a few years now I doubt I would have gone as high as a 20k source impedance. What music source are we planning to use? The eff. input capacitance is around a hundred pf, so you can figure out the FR from there.
In actuality, the buffer is made this way, because it was intended to (also) work with a certain unobtainium part I had on hand in the same circuit with some resistor value changes. That part has an input capacitance of a couple pf.
In actuality, the buffer is made this way, because it was intended to (also) work with a certain unobtainium part I had on hand in the same circuit with some resistor value changes. That part has an input capacitance of a couple pf.
Last edited:
I do feel a bit guilty about writing about unobtainium. I wish I had more control over that. Unfortunately, whenever Nelson or I mention a part number, they seem to start to vanish. Maybe we should start a chip fab
I should probably get back to more obtainable stuff, but this stuff is just so darn fun.
I should probably get back to more obtainable stuff, but this stuff is just so darn fun.
You're welcome. Glad you enjoyed it. I'll check on that. It's been a few years now I doubt I would have gone as high as a 20k source impedance. What music source are we planning to use? The eff. input capacitance is around a hundred pf, so you can figure out the FR from
That would be 50 percent of a 47k pot hung in front of the buffer
It's not the FR per-se that is of direct interest but the impact of the fet's varying input capacitance on THD if a reasonably high impedance pot is used.
No worries though - enough hints so far from you so that I can do the rest
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
- Home
- Amplifiers
- Pass Labs
- LuminAria Article Available