New Tortuga passive/active tube pre looks like a winner

Curious, what about it do you believe to be "innovative?"

+1

Hi All,

Thought I'd pipe in here with some perspective. The LDR3000T is indeed NOT a passive preamp although it does employ our V25 LDR preamp controller/attenuator which is the heart of our current line of passive preamps. Downstream there's a zero-low gain active linestage with a tube input/gain (voltage amplifier) stage followed by a discrete solid state JFET buffer (current amplifier) output stage. We run the tube deliberately zero to low (+6 dB) gain running at a slack plate voltage of only 42 volts. The input stage is direct coupled (no cap) but the output stage does employ a DC blocking output coupling cap. By keeping the plate voltage low we can use the same voltage to run the class A buffer output stage. Some or all of the above tends to illicit cries of heresy and blasphemer from certain orthodox tubies. The active linestage is a second generation derivative of a similar circuit used for the past 2 years in our TBP.V1 Tube Preamp Buffer which has been very well received by our customers. heresy notwithstanding. I make no claims about this design being purely original first-of-kind work but the devil is truly in the details. The overall synergy produces a remarkably pleasing sound that I personally find very enjoyable and satisfying. We think other folks will as well.

Cheers,
Morten

Thanks for info. Everyone will be looking forward to hearing the unit and reading reviews. 

https://www.audiocircle.com/index.php?topic=163967.msg1767308#msg1767308

Initial comments from customers have been positive. Here's a recent customer post on our audiocircle.com forum. I've copied the text below. 

Just got mine today at last. It took a while to finally get to the UK, then Customs kept it for two and half weeks, during which time they wrote me two letters about it. Actual letters. Who does that these days for this sort of thing? It's Dickensian. (And they stung me for $500 tax; not excise, UK sales tax. Win some you lose some.)

Worth it in this case though, for sure. I had been wondering whether I'd spent too much money on a preamp. More than I've spent on one before. Indeed I buy 10x more vintage audio gear than I do new anyway. And how much difference does a pre-amp really make, I started to think.

It's also the first new valve amp I've bought. I've got early Quad II monoblocks (who doesn't at some point or other over here?), but my contemporary amps are all SS. The LDR3000T is currently between English solid state either side: Sugden masterclass phono stage and Nord hypex nc500 dual mono power amp.

The difference it makes to the sound is astonishing. I echo what others have said: clarity, purity, soundstage. But I particularly agree with "clean". It's really unbelievably clean. And natural. Very very natural sound.

And the one thing that I don't think others have mentioned but which is really striking in my system is the bass. Huge extra bass depth and slam, to the extent that I'm almost not sure if it's too much. This is going into Neat SX1 speakers, quite a small floorstander which is not particularly bassy (I love them, but they're quite restrained), at relatively low volumes in a small room.

Anyway, I'm incredibly impressed. I would recommend this amp to anyone. And in the middle of an avowedly neutral SS system (and to "neutralist/naturalist" English ears), I think the little bit of valvery works incredibly well. There's an English word I don't think Americans use: gobsmacked. I am truly gobsmacked by this amp.

Bravo, Morten and pals, and thank you.