Really good actives that bely and justify their parts count and complexity seem so rarely found that I cashed out with a Pass DIY B-1 made with reasonably decent parts to replace my decades old passive.That unit did sound better with the GamuT CD-1 than an older Audio Research SP-9 MKIII in terms of transparency and image width. The GamuT had exceptionally low impedance along with high output which worked very well. The prototype was made using Radio Shack parts and ran about $15 in parts.
Beyond a certain point, however, I have to come to agree with the Co senses that a really good active can better resistive or TVC based passives especially in terms of dynamics at both ends of the spectrum.