G’day all, yes I’ll admit that I went to bed last night thinking about phono stages! Yes I’m a strange fellow, and it probably explains my poor sleep lately too. Being a playback system requiring equalisation does place considerable demands on the phono preamplifier and I never cease to be amazed by despite so called standard playback RIAA equalisation, the sound and quality of phono stages varies so much!
My DIY ESP P06 is my reference but I have considerable fondness for the sound and performance of that little black metal box (well mine is), called the TCC TC-750. It’s really not bad at all, and yes a 12 volt DC power supply really improves it, but mostly because the supplied wall wart isn’t that good and electrically noisy. The ‘single ended’ nature of the circuit without the advantage of good ‘common mode’ noise rejection probably contributes to this so the advantage of a pure DC supply rail (i.e. a battery) is more apparent as a consequence.
Still, the exclusive use of discrete transistor circuitry is appealing to me and is in a sense rather nostalgic. The sort of circuitry used in this phono stage reminds me of my early DIY days playing around with BC549C transistors (still my favourite), and they make very nice audio preamplifiers, similar to the transistors used in the TCC TC-750, and discrete transistors of this type are a lot less noisy than a lot of common field effect transistors (FET’s) too.
Although I now use op amps in everything I still think simple transistor circuitry have some distinct advantages over op amp circuitry, probably in terms of ultimate operational bandwidth and TIM effects. There are a lot of transistors all in overall feedback in a typical op amp chip. A simple two or three discrete transistor package tends to produce a more open and uncompressed sound over many simple full feedback op amp designs I think and the TCC TC-750 certainly does!
It is a good circuit too. My own attempt at building a simple transistor based phono stage a while back was successful, but the whole thing sounded very ‘nothing’, poor dynamics and no sense of ‘life’. My own effort also had a peculiarly interesting tendency to pick up radio stations unless the power supply filtering was just right!
No such issues with the TCC TC-750 at all! Here is the ‘reverse engineered’ general circuit from the Beavis Hi Fi website http://beavishifi.com/ of the very similar LC version. I don’t actually see any advantage of having a ‘level control’, by the way as it is just a passive attenuator, but people like turning another control perhaps. The TCC TC-750 is a very nice and endearing phono stage. Regards, Felix aka catman.
My DIY ESP P06 is my reference but I have considerable fondness for the sound and performance of that little black metal box (well mine is), called the TCC TC-750. It’s really not bad at all, and yes a 12 volt DC power supply really improves it, but mostly because the supplied wall wart isn’t that good and electrically noisy. The ‘single ended’ nature of the circuit without the advantage of good ‘common mode’ noise rejection probably contributes to this so the advantage of a pure DC supply rail (i.e. a battery) is more apparent as a consequence.
Still, the exclusive use of discrete transistor circuitry is appealing to me and is in a sense rather nostalgic. The sort of circuitry used in this phono stage reminds me of my early DIY days playing around with BC549C transistors (still my favourite), and they make very nice audio preamplifiers, similar to the transistors used in the TCC TC-750, and discrete transistors of this type are a lot less noisy than a lot of common field effect transistors (FET’s) too.
Although I now use op amps in everything I still think simple transistor circuitry have some distinct advantages over op amp circuitry, probably in terms of ultimate operational bandwidth and TIM effects. There are a lot of transistors all in overall feedback in a typical op amp chip. A simple two or three discrete transistor package tends to produce a more open and uncompressed sound over many simple full feedback op amp designs I think and the TCC TC-750 certainly does!
It is a good circuit too. My own attempt at building a simple transistor based phono stage a while back was successful, but the whole thing sounded very ‘nothing’, poor dynamics and no sense of ‘life’. My own effort also had a peculiarly interesting tendency to pick up radio stations unless the power supply filtering was just right!
No such issues with the TCC TC-750 at all! Here is the ‘reverse engineered’ general circuit from the Beavis Hi Fi website http://beavishifi.com/ of the very similar LC version. I don’t actually see any advantage of having a ‘level control’, by the way as it is just a passive attenuator, but people like turning another control perhaps. The TCC TC-750 is a very nice and endearing phono stage. Regards, Felix aka catman.
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Download the clips in Post 213, Page 15 and listen carefully. Muddywaters is not releasing the brand names/models publicly, but will tell you by PM which ones you prefer. 