I had repair a VTV 6sn7 line stage preamp for a friend before, he said he had a few preamps include a forplay I had epair for him long time ago, he mention he compare all line stage preamps he own the VTV he like most.
So I always want to build one for myself. Recently I had build one for fun, I also include a MM phono amp, I try to build a bottleheard phono amp but I don't have the schematic, the phono amp I use 6j32p, EF86 equivalent and half 12au7 each channel, at first I try to use 6dj8, but I found my extension power cable socket only had 3 pins, it need 4 pins to lift the filament cathode for 6dj8. This phono amp RIAA network only 3 components but it looks not bad I had check 5 points and the db not off to munch. I had pack 5 tubes inside a compact box. The power supply section I used a Textronix probe power as the housing. I used most parts I already had on hand. I am not a designer, I just try by mistake and make correction. I spent time to read and lean from internet. I hope some one interesting.
So I always want to build one for myself. Recently I had build one for fun, I also include a MM phono amp, I try to build a bottleheard phono amp but I don't have the schematic, the phono amp I use 6j32p, EF86 equivalent and half 12au7 each channel, at first I try to use 6dj8, but I found my extension power cable socket only had 3 pins, it need 4 pins to lift the filament cathode for 6dj8. This phono amp RIAA network only 3 components but it looks not bad I had check 5 points and the db not off to munch. I had pack 5 tubes inside a compact box. The power supply section I used a Textronix probe power as the housing. I used most parts I already had on hand. I am not a designer, I just try by mistake and make correction. I spent time to read and lean from internet. I hope some one interesting.
Attachments
Interesting adaptation of full wave bridge rectifier. Seems there would be an imbalance since voltage drop less across SS diodes.
Jim
Jim
Yes, I like the sound, the phono amp is good, I had a vinyl record disc and a CD disc had the same contain, I play the same song at the same time, then switch the phono/CD switch, I can't tell the diffrent, looks like the RIAA curve was very accurate. The phono amp not much components but result is good.
I like to used the tube rectifier for time delay. It look works good, I don't see any balance issue.
