Krell kav 250a/3 - Input Mix?


Can I mix inputs on this amp? I would like to run balanced inputs from a stereo pre-amp and an rca input from my HT processor for the centre channel if possible. Clearly the amp sounds much better running in balanced mode!
paul_smith
Krell have confirmed that you can mix inputs on the amp.See response below

" At the end of the day though it is possible to use channels in balanced and in single-ended mode at the same time. Two items of importance to note are:

1 - There will be a 6 db gain differential between the balanced and single ended channels. Meaning that the balanced channels will be louder during surround playback. However you should be able to balance this out by doing a system volume calibration via your processor set up menu.

2 - When operating any balanced amp in single ended you will need to short out the balanced input to make sure that noise does not get introduced through it, the result of which will be a noticeable hum or buzz present when attempting playback. We ship all of our amps with shorting pins (brass U pins) installed in the balanced inputs from the factory. These are inserted into pin 1 and 3 on the balanced input."
Paul,
Krell's website has a link to service where you could ask them this question. Go to www.krellonline.com and look for this link. I would be interested to see what Krell has to say. Plus additional posts here from other users would be useful. My local dealer here in the states agrees that this amp is absolutely intended to be used this way. And the owner's manual makes no mention in way of a caution or warning that the user should not mix and match. If you get an answer from Krell, please post it here so we can see what they said. Then perhaps forward it on to your distributor so they can be educated as well.
David.
Thanks for that David. I e-mailed the UK importers for Krell last week and was told under no circumstances to do this as it would damage the amp!At the time I thought it strange as it was my understanding that the 3 channels were independent.I guess they misinterpreted my question.

This is excellent news as it means I can use a stereo pre-amp and not lose a channel.Much appreciated help (having saved me the cost of another amp!)- and even second hand krells are expensive in the UK

Paul
Hello,
This is exactly how I am using my Krell KAV250a/3 - single-ended for the center speaker, and balanced for the L & R. Just remember to use the shorting pin for the center channel when using single-ended output. It works perfectly in this configuration.
The 3 channels of this amp are completely independent, so you can configure each as you wish. I haven't found the amp to sound much better, if any, however, in balanced versus single-ended. However, due to the sensitivity differences in my main speakers vs the higher sensitivity of my center, the balanced connection gives me that extra 6db volume boost that my L&R pair need to match my center. It works great!
David.