Gotta love Nelson Pass

Seems like it become addictive when someone buying First Watt stuff. I decided to buy another preamp for my FW F2J power amp. 

Soon i will be able to compare my FW B1 Buffer Preamp and Pass Aleph L. 

After 7 month of using my B1 i realized that i need at least 4 inputs to switch between different phono stages. The B1 has only two inputs, the Aleph L has 4 inputs. 

Another reason to buy Aleph L was the second output which can be used for an active SUB if i will buy Zu Undertone sub for my Druid speakers. 

It was not easy to find the latest version of Aleph L which is passive if the volume control knob position is not higher than 3 o'clock. I'm sure that i don't need an active gain in my system, because even with B1 buffer preamp i only use 10-20% of the volume control. It was hard to imagine that less than 5 watt Power Amp (F2J) is more than enough for 101db speakers in my big room. 

if someone compared the same preamps (First Watt B1 and Pass Labs Aleph L mkII) please share your experience. 

thanks 

chakster I’m sure that i don’t need an active gain in my system, because even with B1 buffer preamp i only use 10-20% of the volume control.

If that’s right B1 has no gain, you don’t need any gain,
BUT! your FW F2J is only 2kohm input impedance this doesn’t bode well for any passive or tube preamps, even your B1 has 1kohm output impedance, which is not a good look either into the 2kohm of the F2.

You really need a low gain preamp with an output impedance that’s below say 250ohm output impedance for this amp. You could look at the Schiit Ferya low gain with solid state output is 75ohm and the tube output is 210ohm, forget the passive output. Remote, excellent volume pot, cheap! and you can return it.
http://www.schiit.com/products/freya
Cheers George

Hi George
Actually i have F2 upgraded to F2J by Nelson Pass for previous owner.
MOSFETs replaced with JFETs

Input impedance is 50k Ohms which is stated in the original manual that i have on hands. But this is F2 manual, not F2J.

I realized that F2J input impedance is lower ( approximately 25 Kohm )
"So the F2J is recommended for use with preamps with ordinary to low output resistance – tube preamps without cathode followers will work but will not reap as much benefit at high frequencies. "

As Nelson said the F2J has a bit lower input impedance than most are used to, so having a preamp that can provide more current is a good idea. But there is no current production in my B1.

He said the Aleph L in my system would be fine!

P.S. What i don’t want is a tube preamp, i sold all my tube gear before i bought First Watt. Still have nice mega rare vintage tubes, but i want to sell them too. No more tubes at least in the near future.