8 responses Add your response
Yes, an active preamp for sure, but some mistake zero gain for “passive.” Plus, the seller manufactures “passive” LDR attenuators so there may be some inclination to assume the pre is passive since there is no gain.
it seems they have combined their tube buffer (an active, zero gain, buffer) with their LDR attenuator.
You can also order it with +6dB of gain, which may lead some to believe the version without gain is a passive (it is not).
All that said, there is nothing wrong with not going the passive route and in every instance I have tried, I preferred a zero gain buffer or low gain preamp to a true “passive” attenuator or auto-former set-up.
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.
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.)