Cube Audio Nenuphar Single Driver Speaker (10 inch) TQWT Enclosure

"Could you elaborate please on your particular set up for evaluating these amps, the make of preamp and/or dac used with the First Watt amps and dac if any with the Bakoon and LTA? Do you use the VR with its dac board?"

The source is an Aurender N10 paired with a Holo Audio Spring DAC (Level 3) or a COS D1. With the power amps I used a Backert tube preamp, the original Rhythm. The 12au7 tubes were upgraded with NOS Mullards.

I found that I preferred some tubes in the signal path. The SIT-2 and SIT-3 were very close when used directly with the COS (no preamp). To these ears the SIT-2 improved more when the Backert was added to the chain. I could easily live with either of the FirstWatt amps or the Bakoon, but the LTA lacked some musical magic. I never did get entirely comfortable with the volume control on the Bakoon.

Robert

Robert  Please share your findings with tube trials in the VR L2iSE.  I have only tried Electro Harmonix and Elrog 300bs and the Linlai 2A3.
The latter was a clear winner, I mentioned it's attributes in an earlier post and Srajan has a very positive review.  Like to hear what you're rolling.  The Nenuphars obviously love tubes and are a great lens of their different qualities.

My first comparison was between the Electro Harmonix 300b that came with the amp and an EH 2a3 set. I preferred the 2a3 as the 300b tubes were 'slower' even though they had a richer sound. That trade-off was solver with a set of Takatsuki 300b -- the best of both worlds and my current favorite. I do have some KR Audio T-100 DHT on order. I will keep you posted.

In the meantime, I have tried some NOS tubes: 71A and 112a (Most the old tubes seem to run at 5V). The 71A were a bit lean, but the 112a Cunninghams are now in second place after the (pricey) Takas.

Fun days and an embarrassment of riches....

Robert
 

Re the different solid state amps:
I wanted to note that the main difference for me was that the FirstWatt amps had a bit more of the mid-range-icity that is a major attraction of tube SETs.

Robert

I realize that the 300b tube is being discussed in the context of utilization for preamplifier section duty. I've only used them as output tubes in power amplifiers.  I do believe that to get the best from this splendid (My opinion) tube you have to use the premium level options which admittedly are expensive (But worth it).

Elrog, EML,KR, Takatsuki,  these are going to yield exceptionally good sound quality. Worth the cost if you have the level of audio systems/components under discussion here. The Nenuphars will easily reveal the improvement these higher tier 300b tubes provide. I wouldn't cut corners. 
Charles