As a Dyn C1 owner that has upgraded to the C1 Sig I have to disagree/agree with Bruce. I also had the Octave V40se - V70se and currently have the V110.
That being said the original C1 needed to be cranked up (high listening levels)to sound their best. I've had a black box (not super). The black box lowers the noise floor and adds a bit more headroom. The V40 will work but again turn it up. The V70 was a bit better in that it had a hair more 'control' in the sound. Then I upgraded to the C1 Sig. The MKII/Sig DO NOT need to turned up to sound their best. They sound best at low/mid to high volumes. But I am not sure the MKII/Sig can be as loud as the originals. Moot point for me as I prefer low/mid to low/high volumes.
The V110 the last upgrade I've made and it offers a bit more control in the sound when in high (110W power) mode vs the low (70W) mode.
That being said the original C1 needed to be cranked up (high listening levels)to sound their best. I've had a black box (not super). The black box lowers the noise floor and adds a bit more headroom. The V40 will work but again turn it up. The V70 was a bit better in that it had a hair more 'control' in the sound. Then I upgraded to the C1 Sig. The MKII/Sig DO NOT need to turned up to sound their best. They sound best at low/mid to high volumes. But I am not sure the MKII/Sig can be as loud as the originals. Moot point for me as I prefer low/mid to low/high volumes.
The V110 the last upgrade I've made and it offers a bit more control in the sound when in high (110W power) mode vs the low (70W) mode.