In my case, in two systems--no overloading, great sound, yes, worth it.

So who it goes ?
DAC > Zbit > Zrock > Amp ?

Would you add the Pills to that ?

I use Lon's 2nd system setup. DAC-ZBIT-ZRock2-CSP3-Torii IV

The ZBIt converts from balanced XLR to single ended RCA, so for folks without balanced pres, it usually comes after the DAC. It can really shine there by utilizing a voltage bump from most DACs, and running that signal through nicely transparent and smooth transformers, making the DAC sound better to me while giving more gain riding to sound flexibility... part of this is the higher voltage potential from balanced out of the DAC. The ZBIT gain knob makes adjusting DAC voltage easy for sound preferences and gain riding. My DAC puts out about 6 V balanced, then a ZRock2 after the ZBIT, and CSP3 after the ZRock, I use three pre stages. This combo does tend to cause earlier distortion from my Torii... a little earlier, making gain riding trickier for high volume listening. It is especially noticeable with some recordings and less so with others. Guessing compression, release, limiting edges in mastering, and the like probably play a roll there...

Anyway, I am used to just thinking I have earlier distortion with 3 stages in front of my Torii...two being less prone to early distortion. And my Torii is toned down some to complicate matters. I like the sound better with tubes that do not pull absolutely all the available power. In combo with earlier distortion from the using my 3 pre stages, my ±92 dB speakers are a little inefficient for my loudest listening volumes in my relatively large space. Normally playing much lower volume, it is gorgeous and satisfying for most of my listening, but in late night, lost in the music mode (at the seat), I am near the edge of distortion for this setup. Guessing that if I had say 95 dB speakers, I might not have noticed this.

So I need to try to measure the output voltage of the ZBIT and make sure it is under 4 volts based on the spec Dom gave us of a 4 volt max for the ZRock2 and check that out. I wonder if it is this, or some other voltage/impedance issue with more and more pieces in a chain? Anyone?

Interesting. So I wonder if anyone can tell me why I get a little easier distortion with these 3 pre-amp stages in succession over two or one. I have never taken the time to learn the details of voltage and impedance when combining gear like this, or even know where to look. I just assumed all Decware will work together really well, and this thing has had me a little buffaloed. But the sound is so good, I live with it, just running my late night sessions near the edge.. wishing I could go a touch past that at times.

Dom, there's a number of things I have found over the years that are either cut and paste victims from previous versions, or not updating manuals fully. I've pointed out a lot to Steve. . . but don't always want to, don't want to be "that guy" pestering about things.

The way the ZROCK2 acts in my systems I'm pretty sure that the 15 volt total is accurate--I can pump a lot of gain into that component!

Lon…I’m sure the 15 volts max is accurate.  Thanks for clearing that up.  I just want to make sure the OP is getting accurate information…especially if he is looking to purchase a component.   Gain riding is a great tuning tool and I’m glad I incorporated a ZBIT into my system with the addition of the ZROCK2.

I recently swapped out a 12AU7 in my ZSTAGE and tried a 12AT7WA.  It’s still breaking in, and while I don’t think it’s going to stay, the addition of the ZBIT allows my to tailor the gain coming off my dac to compensate for the higher gain on the 12AT7 tube.  The manipulation of the ZROCK2 also allows me to take some of the edge and brightness off the 12AT7 by adding a bit more bass.

Dom