Looking to buy Firstwatt B5,4 ,F2J, SIT-1, SIT-2, SIT-3 and any DIY alternatives
Looking for single ended jfet or sit 0 feedback amplifier
Single ended 0 feedback preamp
Active crossover boards
Looking for single ended jfet or sit 0 feedback amplifier
Single ended 0 feedback preamp
Active crossover boards
I'm looking for some of them, whichever lot comes first.
SIT NEMESIS, F2j, SIT-1 and B4 and are most desired.
SIT NEMESIS, F2j, SIT-1 and B4 and are most desired.
If there are 10 completed SIT Nemesis in the world, I’d be surprised. You’ll almost certainly have to build your own.
….Which is super fun.
🙂
….Which is super fun.
🙂
Ok, let’s turn the hinting and subtlety off for a moment...
There is exactly one verified build of the Nemesis, and that included the ones that Nelson built and then disassembled. The one may be for sale, but I have no idea. Perhaps the builder would contact you if he’s interested. But outside that, you wont find one.
The SIT-1, -2, -3 amps are not DIY projects and they have all been factory built. If anybody here has one, I suspect it’s not going to be for sale.
F1J, F2J have been done DIY, and with excellent results. There are still PCBs and parts available if you search around, as the most straightforward way to get one of these if to build it yourself.
B4, B5 were never official DIY projects, there may be some but are likely veroboard projects. Not sure there were ever PCBs made. (Maybe?)
If you want zero-feedback amplification, look at the Burning Amp series, BA-2, BA-2, BA-3. They are excellent and have not requirements for hard-to-find parts or processes.
So to reiterate, build a F2J or BA-series amp. It’s fun, you will love it, and the process is fantastic, educational, and satisfying.
🙂
There is exactly one verified build of the Nemesis, and that included the ones that Nelson built and then disassembled. The one may be for sale, but I have no idea. Perhaps the builder would contact you if he’s interested. But outside that, you wont find one.
The SIT-1, -2, -3 amps are not DIY projects and they have all been factory built. If anybody here has one, I suspect it’s not going to be for sale.
F1J, F2J have been done DIY, and with excellent results. There are still PCBs and parts available if you search around, as the most straightforward way to get one of these if to build it yourself.
B4, B5 were never official DIY projects, there may be some but are likely veroboard projects. Not sure there were ever PCBs made. (Maybe?)
If you want zero-feedback amplification, look at the Burning Amp series, BA-2, BA-2, BA-3. They are excellent and have not requirements for hard-to-find parts or processes.
So to reiterate, build a F2J or BA-series amp. It’s fun, you will love it, and the process is fantastic, educational, and satisfying.
🙂
Or, DIY . Design It Yourself. A single ended, non-feedback preamp is an especially straightforward task. Non-feedback guarantees it won't be DC coupled, and that simplifies the design. Get yourself a pile of ZTX851s and ZTX951s, the lowest noise bipolar transistors currently available, and start drawing. These are perfect for moving coil pre-pre designs. Excellent for multistage, no-feedback, passive RIAA. Fantastic for line amps. You'll need a high performance power supply, but of course it won't be regulated: that requires feedback. Cascade two or three capacitance multipliers, install power up/down protection diodes as needed, job done. 40dB + 40dB + 40dB = quite good attenuation of 50/60 Hz hum.