Krell 400 XI

Please have me advised. I recently bought a Krell 400xi new from a local dealer.The mid and the high are impressive. The sound stage is fairly good comparing with some of the MF I used to own.The only disapointment is I cannot get the bass right. It is not boomy just not defined and very weak. We are talking abt Krell attack here but I could not find any "attacks" at all. I use a small 5" two way book shelf speakers. I could not find any dedicated sub-output but a pair of pre-out. What is the best way to hook up a sub-woofer to this intergrated amp.since I am not ready to purchase a full range speakers yet. Thank you.
not to worry, it's most likely not broken in yet! Give it at least 500 hours before you even think twice about the bass.
Use the pre out for your sub hookup. You will need a sub that will accept RCA connection AND that has an adjustable crossover so you can blend the sub with your mains - not too much overlap in frequency.
Thank you for your response. I called Krell and they told me flat-out that it was the function of my bookshelf speakers as a result of lacking of bass. I just wonder if any other 400 xi owners who use bookshlef speakers having the same problems. It seems like either I need to hook-up a sub-woofer or to purchase a new pairs of full range speakers. Regards,
I own the Krell 400 .
The amp works well with Alon 11 louspeakers. It prefer 8 ohm and more than 85 db sensitivity speakers to prevent overheating !
The bass is very good after optimising the power supply.
Tks, Kpw. It is really warming up now. Especially. around 60/65 db, bass is quite good. My usual listenning level is around 40/55 db, that's why I cannot get much bass out of the 5" woofer of my bookshelf speakers.
Kpw, what do you mean "optimising the power supply"? Did you mod your unit?

BTW, I'm getting great bass response from my 400xi. I'm using full range floor stand speakers de-coupled from the floor.
Anyone has any problems with the overheating issue of your 400XI. someone told me according to Stereophile reports, the 400XI had some overheat issue. None of mine does. A lot less heat then B&K or Adcom amp.
I have a 400 xi running a pair of gallo reference 3.05. While both units need break-in time out of the box, there has been no lack of bass response. I have driven these speakers witb tubes on the main input with and without the gallo sub amp on the 2nd voice coil. I also powered the main input with appropriate B&K and Bryston amplification. In the end nothing rivaled the 400xi except the tube/gallo setup that reqiured quite a bit of tweeking and a crazy feedback loop through voicecoil #2. In the end the control of the Krell in this budget minded application won hands down. Quite the pairing with a good/great DAC in line for the price. So my experience in regard to bass response via the 400xi, with budget in mind, the outcome is most dependant on the room, placement and displacement of the driver.