DIY Front End 2022 Essentials Kit
Among the appreciations of DIYers is stuff that works simply, well, and cheap, not necessarily in that order.
This project is an effort to assemble these elements into a discrete gain stage that can be used as the front end for modest power amplifiers or as a general audio gain circuit.
For more information including the article PDF itself, please read the DIY Front End 2022 thread on diyAudio.
What's included?
- Each kit includes two circuit boards, providing for two channels
- 12 matched J113 JFETs
- 2 KSA992 bipolars
- 4 resistors matched to the JFETs
Easy to assemble. I may opt to bypass the output cap and adjust the DC offset so I installed the trimmer pot. The JFETS were not all matched but I screened them and found two sets of four so they should work out well. I used my own resistors and KSA992s. Nice boards. I will have them in an enclosure playing soon. Cheers.
Works, sounds, and measures quite good. Very happy with it.
Transparent, detailed gain without sterility. I would call it top notch to enhance without detraction or subtraction from virtues of the amp stage.
Single ended usage @ 36v, used with Pass DIY Sony single ended SK60 VFET, superb.
The FE2022 impresses me in four ways:
1. It has a balanced frequency response, reaching deeper lows without an excessive emphasis on upper bass. It also maintains a flat response in the presence and super high-frequency regions.
2. My build is exceptionally quiet, which enhances its ability to capture fine details, N + THD < -90dB with 48V SMPS
3. It shines in creating a realistic soundstage, with a black background that allows the sounds to stand out with clarity and precision.
4. Last but not least, it has a wide volume control range from 0 to 80 steps, making it highly functional. This is visually displayed and realized with an 10k APLS potentiometer. My build has max gain limited to 6dB, with R3 = R4 = 20k
I received the pcbs and the nicely matched J113 in the essential kit a few weeks ago.
I use it at the moment as a preamp. A very good sounding preamp! Not the drive capabilities like an ACP+,
close to the clarity and more analytic sound of Waynes Line Stage.
I am running it in dual mono configuration. I have built two PSUs (linear regulated after CRC-filter / +-20 V DC -rails) and it is very low noise.
It is a beautiful - simple circuit! I have put more efforts on the PSU. You get this at a bargain!
One possibility to avoid buying precious TOSHIBA or LINEAR SYSTEMS- JFets.
Your chance, if the next run is getting to the shop. Thanks to Nelson Pass and the DIYAUDIO STORE-team!
Enjoy the sound
Dirk
Being a 53 yr old newbie in the world of DIY Audio I have no idea what to say except it sounds great paired with the Mofo.