Uploaded October 2020 | Updated September 2026, 3 days ago
I decided to build the Bryston BP26 Preamp clone from the bare board sold on eBay. If you're interested just search BP26 Bryston on eBay, I'm sure they are still available.
I did this because I own a Bryston 4B SST power amp and given my current preamp (Acurus) was 25 years old, I felt it was time for an upgrade and the idea of having an fully balanced, all Bryston monitoring system was too hard to resist. In the end, it was a long process - made longer because of delays in parts due to COVID restrictions, my unending search for perfect 'feeling' rotary switches, my addition of a balance pot which is not part of this board's architecture and my decision to design my own +/- 24 VDC supply.
The only thing you get with the kit is the bare, unstuffed preamp board. Everything else is up to your system/mechanical design chops and of course, your imagination. Some patience is required decoding some of the parts listed on their BOM and if you're like me - Google translate (from Chinese) REALLY comes in handy here. I designed a faceplate and had one made by Front Panel Express. I'm never going to sell this, and as such don't feel bad for duplicating the Bryston logo (which I did in Illustrator, calling upon my past life as an art director).
This unit ended up being a bit more complex than it needed to be, mainly due to my (wise) decision to keep the AC transformers out of the box as Bryston does which eliminated the need for hours of RFI suppression voodoo that I would have had to deal with, AND my insistence on using the rotary power on switch which i spec'd, which was not designed to handle the amplitude AC voltage i would have had to put through it, so it required four added relays to engage power to the 24 volt supply and +5 and +12 reference voltages needed by the preamp board. The relay board is a pre-assembled unit designed for Arduino projects. This is also why i had to duplicate the +5 +12 volt DC normally on the preamp board itself. I go into these details in the video.
I did not use the other 24 VDC kit intended for this preamp. The BOM was dodgy and didn't spec the transformer the one i got was 56 VCT, much bigger than required. It was less expensive for me to design my own supply, given i had all the parts/perf boards to do it. Oddly, my supply isn't that much different than the one Bystron originally designed for their 1B Preamp (schematics are online (linked below) and why i assume this preamp board was made as the schematics for the entire unit are also online, published by Bryston themselves).
After my final 24 VDC supply was mounted notice a large single cap hung an a 90 degree angle on the end that faces the relay board (there's a real good shot of it around 8:00). This is the 4700uf filter cap for the bridge rectifier on the small +5 and +12 volt supplies that hang off the back of the power switch assembly. It was too big to hang locally on that tiny little perf board, so i did it by routing the wires from/to the PSUs to the isolated capacitor which converts the AC to DC leading to the two switching regulators. A little kludgy, but this is to be expecting with the number of engineering decisions/solutions required to take a bare board to a completed unit designed for years of daily usage.
The board comes ready for XLRs (balanced) and RCA (line level) connectors. I hate RCAs, and decided to use TRS 1/4 inch phone jacks for all of them, including the balanced I/Os. As a safeguard, I incorporated twisted pairs in all cases (highly recommended). Note: when i mention "wallwart", it's actuly a homemade box contaning the two fused AC transformers tht connect to the wall on one end and my 5 pin XLR connector which brings the secondary transformer voltage into the box itself.
As reference - before you start - know that this preamp as you see here ran me about $500 all things said and done. Sorta/kinda pricey, yet still only a fraction of what a store bought BP26/Power system would run. There's a reason for this, above and beyond Bryston exercising its full right to charge a premium for their products - which i say is justified . The real BP26 has many more input selection options, including a RIAA rated phono input, a remote control and a myriad of additional monitoring mode. This clone however does have the benefit of Bryston's legendary discrete D0433 op amp design (six in total).
Also take this as certification that the PCBA, when completed, is 100% functional. The art is good. If your unit isn't working, it's due to an error you made along the way.
The unit is done, this video documents the journey, including the stupid mistakes i made along the way. Highlights can be found at 6:45 when i apply full system power, 9:16 when i do the initial audio tests and 11:25 when it's completed and demo'd in my rack. I can't see anyone sitting through the whole thing, but best of luck trying.
Bryston B1 Preamp schematics online:
manualslib.com/manual/355786/Bryston-1b.html#manual
I decided to build the Bryston BP26 Preamp clone from the bare board sold on eBay. If you're interested just search BP26 Bryston on eBay, I'm sure they are still available.
I did this because I own a Bryston 4B SST power amp and given my current preamp (Acurus) was 25 years old, I felt it was time for an upgrade and the idea of having an fully balanced, all Bryston monitoring system was too hard to resist. In the end, it was a long process - made longer because of delays in parts due to COVID restrictions, my unending search for perfect 'feeling' rotary switches, my addition of a balance pot which is not part of this board's architecture and my decision to design my own +/- 24 VDC supply.
The only thing you get with the kit is the bare, unstuffed preamp board. Everything else is up to your system/mechanical design chops and of course, your imagination. Some patience is required decoding some of the parts listed on their BOM and if you're like me - Google translate (from Chinese) REALLY comes in handy here. I designed a faceplate and had one made by Front Panel Express. I'm never going to sell this, and as such don't feel bad for duplicating the Bryston logo (which I did in Illustrator, calling upon my past life as an art director).
This unit ended up being a bit more complex than it needed to be, mainly due to my (wise) decision to keep the AC transformers out of the box as Bryston does which eliminated the need for hours of RFI suppression voodoo that I would have had to deal with, AND my insistence on using the rotary power on switch which i spec'd, which was not designed to handle the amplitude AC voltage i would have had to put through it, so it required four added relays to engage power to the 24 volt supply and +5 and +12 reference voltages needed by the preamp board. The relay board is a pre-assembled unit designed for Arduino projects. This is also why i had to duplicate the +5 +12 volt DC normally on the preamp board itself. I go into these details in the video.
I did not use the other 24 VDC kit intended for this preamp. The BOM was dodgy and didn't spec the transformer the one i got was 56 VCT, much bigger than required. It was less expensive for me to design my own supply, given i had all the parts/perf boards to do it. Oddly, my supply isn't that much different than the one Bystron originally designed for their 1B Preamp (schematics are online (linked below) and why i assume this preamp board was made as the schematics for the entire unit are also online, published by Bryston themselves).
After my final 24 VDC supply was mounted notice a large single cap hung an a 90 degree angle on the end that faces the relay board (there's a real good shot of it around 8:00). This is the 4700uf filter cap for the bridge rectifier on the small +5 and +12 volt supplies that hang off the back of the power switch assembly. It was too big to hang locally on that tiny little perf board, so i did it by routing the wires from/to the PSUs to the isolated capacitor which converts the AC to DC leading to the two switching regulators. A little kludgy, but this is to be expecting with the number of engineering decisions/solutions required to take a bare board to a completed unit designed for years of daily usage.
The board comes ready for XLRs (balanced) and RCA (line level) connectors. I hate RCAs, and decided to use TRS 1/4 inch phone jacks for all of them, including the balanced I/Os. As a safeguard, I incorporated twisted pairs in all cases (highly recommended). Note: when i mention "wallwart", it's actuly a homemade box contaning the two fused AC transformers tht connect to the wall on one end and my 5 pin XLR connector which brings the secondary transformer voltage into the box itself.
As reference - before you start - know that this preamp as you see here ran me about $500 all things said and done. Sorta/kinda pricey, yet still only a fraction of what a store bought BP26/Power system would run. There's a reason for this, above and beyond Bryston exercising its full right to charge a premium for their products - which i say is justified . The real BP26 has many more input selection options, including a RIAA rated phono input, a remote control and a myriad of additional monitoring mode. This clone however does have the benefit of Bryston's legendary discrete D0433 op amp design (six in total).
Also take this as certification that the PCBA, when completed, is 100% functional. The art is good. If your unit isn't working, it's due to an error you made along the way.
The unit is done, this video documents the journey, including the stupid mistakes i made along the way. Highlights can be found at 6:45 when i apply full system power, 9:16 when i do the initial audio tests and 11:25 when it's completed and demo'd in my rack. I can't see anyone sitting through the whole thing, but best of luck trying.
Bryston B1 Preamp schematics online:
manualslib.com/manual/355786/Bryston-1b.html#manual
