Testing later today to confirm, but last night I was able to achieve a level of sound quality that quite frankly caused a jaw drop. The baseline for comparisons during the development phase are two solid state preamps that I love the sound of, an A Designs Pacifica and a Vintech X73i. Obviously, there are going to be differences with tube vs. solid state, but a great preamp is a great preamp regardless of topology. The Pacifica has largely been the main baseline comparator, in regards to frequency response, linearity, and noise. The X73i was also compared against, but more for a reference of gain since it has nomenclature for indicating dB. The Pacifica is the favored of the two test subjects since it has a lower noise floor, more gain and a slightly cleaner sound. Why am I using these 2 name-brand preamps for comparisons? Because that's the best of what I have at LBA Studios.
The goals for the development of Trinity in order of importance
Last night the sound was so impressive coming out of the Trinity prototype. It achieved all of the goals and actually outperformed the Pacifica in terms of noise performance. The level of fidelity sounds more accurate to my ears than the Pacifica, which let me say was a massively daunting task. I actually tried something like 80-100 different designs before finally coming up with this one. I can proudly say Trinity has a gorgeous, dark, underlying tone with an impressive level of detail across the spectrum. Its what I will call a linear vacuum tube mic preamplifier, since it amplifies in an extremely linear manner - very unlike most tube designs. It currently has 3 vacuum tubes per channel, but has relatively low gain for all those tubes. There are two 7025 tubes and one 6922 per channel. I will later confirm the exact dB of gain, but my suspicion is its somewhere around 60dB. That may be on the low side for modern mic preamps, but honestly, the sound of this thing is just so amazing I think anyone can easily overlook that element. For all intents and purposes, I believe it has enough gain for most situations. It may have trouble with ribbon mics used on spoken word, but even if you crank the gain all the way its level of noise is still extremely low.
I was really trying to avoid designing this to have 3 tubes per channel. If I were able to keep it to 2 tubes per channel the price tag would be significantly lower. Turns out 3 tubes were necessary to achieve the level of fidelity I was reaching for. It looks like I will have to sell Trinity for close to 4 grand, which I was trying to avoid since it will be more difficult to sell at that price point. However, it does offer a lot of really impressive features that most preamps don't offer. We're talking about a stereo channel strip here, so 4 grand really isn't that insane of an asking price for something of this pedigree. We'll see how it goes though. I have yet to build a production model.
About the Author
Mike Congilosi II, Inventor/Engineer