T-preamp TCC TC-754 preamp

[JiiPee]

This one seems interesting. A preamp with volume control, phono preamp, and three extra RCA inputs - All for less than 100 €
T-preamp

Any thoughts, or even measurements regarding this one?

 

[AnalogSteph]

Talk about a blast from the past. I hope you are aware that these have been around since the mid-2000s if not earlier. Aside from the phonopre which appears to be the same 3-transistor circuit as the TC-750 (note: it has been found that the 360k resistor should ideally be more like 310-320k to alleviate the bass bump), I don't think there is much preampification going on in this unit, maybe an emitter follower buffer (those 2 transistors on the right?). TC9208N input switch, 4013 for the logic.

T-Preamp TCC TC754 - 3 inputs preamp with MM phono stage - [English]

Seems to be sensitive to output loading, perhaps some of the 1µ/50s on the right are the output coupling caps.


The "5 V" lettering is most likely incorrect, the TC-750 shipped with something closer to a 15 V supply. (If you find a hand-drawn schematic of that thing, I drew that all the way back in 2008.) Ah yes, the review says 12 V. That's what you would expect.

I wonder how they're getting a negative supply for the input switch, is there a rail splitter somewhere?

 

[JiiPee]

Talk about a blast from the past. I hope you are aware that these have been around since the mid-2000s if not earlier. Aside from the phonopre which appears to be the same 3-transistor circuit as the TC-750 (note: it has been found that the 360k resistor should ideally be more like 310-320k to alleviate the bass bump), I don't think there is much preampification going on in this unit, maybe an emitter follower buffer (those 2 transistors on the right?). TC9208N input switch, 4013 for the logic.

T-Preamp TCC TC754 - 3 inputs preamp with MM phono stage - [English]

Seems to be sensitive to output loading, perhaps some of the 1µ/50s on the right are the output coupling caps.


The "5 V" lettering is most likely incorrect, the TC-750 shipped with something closer to a 15 V supply. (If you find a hand-drawn schematic of that thing, I drew that all the way back in 2008.) Ah yes, the review says 12 V. That's what you would expect.

I wonder how they're getting a negative supply for the input switch, is there a rail splitter somewhere?

Thanks! This is pretty much what I suspected. I was just wondering, because there seems to be quite a few positive comments about it in the 'net. Just goes to show...

 

[Clmrt]

I've had one for a long time. It works well enough. Not sure how it performs, analytically speaking.