I decided to take her apart last week to make some modifications. The previous amplifier topology was SRPP, which worked well, but after hearing a number of my mixes through this board I felt it was too colorful. Yes, there's such a thing as too much color! Plus, the tone of SRPP amplifiers is slightly gritty IMO. I wanted a smoother cleaner tone, like what I'm getting out of my Trinity channel strips. That required a new power supply for the board, more tubes, and a whole lot of work. But, now that its done and working I can say it sounds exactly as I had hoped... maybe better! I also needed to add a couple extra controls that I felt were necessary after working with this board for about a year. I added a VU meter kill switch (sometimes I like slamming the output of the board, which pegs the VU needles). I also added VU meter L/R calibration pots. I felt like the meters were too arbitrary before, so now I can dial them in exactly. Lastly, I changed the role of the trim pots from being amplifier input volume controls to output attenuators (post output transformers). This just makes a whole lot more sense to me, because now I can attenuate any noise from the amplifier stage when I attenuate the volume. Speaking of noise, that was a subtle trade-off switching from the SRPP output stage to what is now single-ended. Simplicity and noise rejection are the hallmarks of the SRPP topology. Super sexy tone, low noise (practically as good as SRPP), wider frequency response, greater degree of amplification, and much lower THD are the benefits of the Trinity design, which is a single-ended, Class A, ultra-linear pentode amplifier. I you want to hear the board before all this, you can check out my past work at www.lbastudios.com. It will be a little bit before I can get some new mixes done through the updated board. I'm really looking forward to it though!
About the Author
Mike Congilosi II, Owner/Designer/Electronics Engineer at Lightning Boy Audio and Owner/Audio Engineer/Music Producer at LBA Studios.