If someone opt for a Gainclone would be cheaper than to opt for an amplifier using coupling audio transformers, because when we need high-quality xformers, the cost increases greatly, and would need to order the transformers tailored for that because the off-the-shelf parts are small toys, compared when really necessary (or if you need only an sound-blaster, its OK with off-the-shelf parts, but even the output power sometimes sucks if the trafo is high internal wire resistance).
I built one of these with 2SD226 + 2N3055 in mono for my car subwoofer ("only" 50W in 4R, but as I do not want to go deaf, an my sub is reasonable efficient ...). I did the custom transformers, and only for bass use. They work from almost 10 Hz, with well balanced internal resistences from emmiter-to-emmiter, but are unstable to treble use. I used 1A/output transistor quiescent current, because this amplifier works in open loop, and to have some damping factor, it will have to come from somewhere, and this place would be through the transconductance of the output transistors (so it must be active with some quiescent current to have some transconductance). I modified my car radio internals to outputting sub in the rear AF out (I use midrange/treble at RCA out).
I built one of these with 2SD226 + 2N3055 in mono for my car subwoofer ("only" 50W in 4R, but as I do not want to go deaf, an my sub is reasonable efficient ...). I did the custom transformers, and only for bass use. They work from almost 10 Hz, with well balanced internal resistences from emmiter-to-emmiter, but are unstable to treble use. I used 1A/output transistor quiescent current, because this amplifier works in open loop, and to have some damping factor, it will have to come from somewhere, and this place would be through the transconductance of the output transistors (so it must be active with some quiescent current to have some transconductance). I modified my car radio internals to outputting sub in the rear AF out (I use midrange/treble at RCA out).
Very DIY
And will be far cheaper
If one make from scratch, perfect, but I already have an good "OVC" woofer, and the "normal" amp also serves to testing and selecting normal one VC models.
Some time ago (2001) I saw an interesting application for an 2R DVC woofer: an "stereo" BTL Toshiba chip amp 2R load capable, with enclosure being an 8" "bazooka". It seems to be an '90's design. With "1R equivalent" BTL the power is the same from my amp in 4R load (theorethical 72W).
With sufficient transistors and low rdc from inductor, one will obtain more than 250Wrms in 1R, or more yet if uses an transforming ratio.
And will be far cheaper
If one make from scratch, perfect, but I already have an good "OVC" woofer, and the "normal" amp also serves to testing and selecting normal one VC models.Some time ago (2001
) I saw an interesting application for an 2R DVC woofer: an "stereo" BTL Toshiba chip amp 2R load capable, with enclosure being an 8" "bazooka". It seems to be an '90's design. With "1R equivalent" BTL the power is the same from my amp in 4R load (theorethical 72W). With sufficient transistors and low rdc from inductor, one will obtain more than 250Wrms in 1R, or more yet if uses an transforming ratio.
hi denver, this is ian, i am so interested, but are you still there? it is already 12 years ago.... hu hu hu hello...
My email is note4ianb@gmail.com
My email is note4ianb@gmail.com
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