follow up with the question about whether Boulder 866 can incorporate a subwoofer in the system or not? The answer is still "yes" instead of NO. In fact for all type of amplifier be it a power amp or an integrated amp you can still add a subwoofer in the system. The caveat is actually you need to choose a subwoofer that is more specific to HIFI system instead of for Home Theater system. A sub that that is designed specifically for HIFI system will usually incorporate a "High Level Input" where by signal is being sent to the sub via the speaker out-put terminal. This kinda connection is more suitable to HIFI system as the signal is direct and you will experience less delay compare to using the pre-out/LFE.