Part of my "DIY Journey" involves building a balanced (as in double-ended completely through) amp. There's been any number of suggestions on this forum for single-ended designs you could adapt to such use, and indeed some noted higher-end designs (e.g. Gilmore Reference) use this approach.
It's been suggested, to myself and others, that a number of simpler designs (CMOY, Szekeres, VanWaarde) could be pieced together into balanced design.
One of my concerns, however, is that people who build the Gilmore and similar high-end DIY projects have the quality (read-expensive) test equipment to ensure that component matching isn't an issue, so performance tolerances for the different phases are likely to be pretty tight. Also, those higher-end designs likely wouldn't suffer from thermal drift or other circuit performance inconsistencies like some of these simpler designs have been documented to have.
Seems to me that getting the phases to mirror exactly is a pretty critical aspect of making a balanced build work. Otherwise what you'll end up with is two great stereo amps wired together that sound like crap.
Is there anyone who has done balanced builds who could suggest a topology that might help me alleviate the matching issue? Is there some kind of feedback/differential/servo mechanization that would compensate for thermal/component mismatch error?
...Or am I making a mouse out of a molehill?
I've seen a number of balanced mic preamp circuit designs, and dsavitsk actually provided me with a nice link to get started, but I really am a novice circuit-design wise, so anything that would help me synthesize all this would be of great help.
And yes, I'm still trying to keep the design simple and parts count low. I want to have my cake and eat it too, though I think I've comfortable with the realization that building a balanced amp may needs to be a bit more complicated than wiring 4 simple amp circuits together.
It's been suggested, to myself and others, that a number of simpler designs (CMOY, Szekeres, VanWaarde) could be pieced together into balanced design.
One of my concerns, however, is that people who build the Gilmore and similar high-end DIY projects have the quality (read-expensive) test equipment to ensure that component matching isn't an issue, so performance tolerances for the different phases are likely to be pretty tight. Also, those higher-end designs likely wouldn't suffer from thermal drift or other circuit performance inconsistencies like some of these simpler designs have been documented to have.
Seems to me that getting the phases to mirror exactly is a pretty critical aspect of making a balanced build work. Otherwise what you'll end up with is two great stereo amps wired together that sound like crap.
Is there anyone who has done balanced builds who could suggest a topology that might help me alleviate the matching issue? Is there some kind of feedback/differential/servo mechanization that would compensate for thermal/component mismatch error?
...Or am I making a mouse out of a molehill?
I've seen a number of balanced mic preamp circuit designs, and dsavitsk actually provided me with a nice link to get started, but I really am a novice circuit-design wise, so anything that would help me synthesize all this would be of great help.
And yes, I'm still trying to keep the design simple and parts count low. I want to have my cake and eat it too, though I think I've comfortable with the realization that building a balanced amp may needs to be a bit more complicated than wiring 4 simple amp circuits together.
