Firstly, if you haven't yet purchased the miniDSP Flex, wait. I've heard from reliable sources that they are coming out with a device that will be Dirac DLBC/ART compatible. It was supposed to be launched this month, but with each passing day it's not looking good for an April launch. The most recent mention, under his breath, was by Mathias from Dirac when he mentioned in the same sentence that there is a new device that "will be coming" that can support ART, and then said that miniDSP has some very good devices, and continued on by saying that they at Dirac always recommend to their partners to offer at least 16 channels. We will see, hopefully soon.
Regarding the Khartago amps, these seem interesting to me. Especially with the prospect of: "Custom bias for your system prior to purchase. The customer has to provide system information to check feasibility. Free of charge."
I would want to know more about the output power at various impedances.
But, since this company has some upgrades available, and since the amps are reasonably priced, I would definitely go for whatever upgrades are possible. Also, the 20 warranty on parts is excellent! It's 2 years labor.
The Khartago vs Emotiva HC-1 is a mixed bag.
Khartago uses a 400VA power supply.
Looks like 8 output power devices at 110 Watts.
Unbalanced Input.
Class A/AB - how much of the power is Class A?
HC-1 uses a switch mode power supply.
6 output power devices.
300 Watts @8Ω, 600 Watts @4Ω,
Balanced and Unbalance inputs.
Class AB only.
I own a HC-1 and it works very well. I tested a pair of them with my 13A speakers and was comparing the sound to my Krell S-1500 amp I had been using. Soundstage was better with the HC-1 mono amps, but the sound otherwise was so close to the Krell that I decided to continue to use the Krell for my 13A speakers. However, I continue to enjoy an HC-1 with my Focus center speaker. Full disclosure, I currently use a different Krell for my 13A speakers.