Krell KAV-250a/3 or KAV-500?

I have a Krell HTS 5.1 and Thiel CS 1.5s, and I'm trying to decide which three channel amp to get. I'm strongly biased toward matching the preamp and amp, so I'd like to get something else from Krell. Does anyone have any opinions on the KAV-500 (in 3 channel configuration) versus the KAV-250a/3?
Are the three channels for the front 3 speakers (L-R-C) or for the Center and surrounds/rears? If you are looking for a 3-channel amp for the LCR speakers I would recommend the 250. If you are looking for an amp for the center and surrounds then I would throw in the 500. But this partially depends on what amp you are driving the front LR speakers. With 2 of the channels bridged to one on the 500, it is supposedly rated at 400 watts per channel. In my opinion, others may certainly differ, if you are running 3 channels for the front 3 speakers having similar power to each in this case is probably a better move (ie. the 250). Of course the 500 gives you great flexibility running all 5 channels (vs. bridging) and allows for you to use 2 of these channels for a second zone as well (assuming you only need three for the main zone).
I had a Kav-500 3-channel driving my center and rears for a couple of years...a nice little amp. I would guess that the two amps have the same sonic signature...the Kav-250 would have a good deal more, "power to spare" may want to consider this factor in?

The 3-channel Kav-500 has a 1 kva transformer, and is rated as 120 watts at 8 ohms load....240 watts at 4 ohm load. It's sound is highly detailed, but not, "over the top" bright (still, maybe not a good match with some tweeters)...pretty good bass too, for only a baby Krell.

This will be for the fronts and center.
I would go with more power then. The Kav-250 probably has twice the transformer size of the Kav-500...the center and mains will hit it hard, as that is where most of the sound is in movies.

I used a Ksa-250 with my Kav-500...Apogee Duettas for mains, and Apogee Centaur Minor for center, and rear duty....this was a few years back....(early multichannel SACD days).

I concur, with Sogood51, without a doubt for the front 3 speakers.
Is power the only factor for that? The Thiels are 4 ohm speakers, so the KAV-500 would be giving them 240 wpc. The recommended power for the speakers is 50-150 watts. It seems like even the KAV-500 would be plenty, and the 500 wpc at 4 ohms that the KAV-250a would provide would be excess.
I did hook the Kav-500 to my 4ohm Apogee Duetta Signatures while I owned it. As I stated, the Kav-500 usually drove my center, and rears...a Krell Ksa-250 drove the Duetta Signature front L+R speakers at that time.

The little Kav-500, had no problem driving the "fairly large" Apogee panels to quite hi spl's in my room. I'm not up to speed on the Thiel CS 1.5s though?

I found an old Stereophile review of your speakers, the Kav-500 will drive them with ease.

BTW...use balanced connections with Krell amps.

Thanks Dave, I'll definitely check out balanced connections. I have an integrated amp now (an old Creek), so I don't have amp to preamp interconnects. I'll have to demo a few different things to see what I like the best.

Other than power, do you think there are any differences between the KAV-250a and KAV-500? I've listened to the 3250 and know I like that, but for financial reasons I'm going to be going with something a bit older. The 250a goes for a bit more than the 500, but if there's a marked difference in sound quality it would be worth it. If not, I'll go with the 500, and use the extra cash for media.
Donnelly asked:

"Other than power, do you think there are any differences between the KAV-250a and KAV-500?"

I don't know, my best guess would be that they sound a lot, a like. The biggest difference in sound, between amps cut from the same cloth (IMHO) is the difference between their power supply/transformer size. This would come into play (or not)...depending on the speakers used, room size, spl's required...ect. At normal listening levels (75-85db) I would expect, that the Kav amps sound similar.

The Kav-500 "does not" sound like the old Ksa-250 I had. The Ksa-250 had a relaxed tonal presentation...the Kav-500 has a more forward sound, more detailed (lots of twinkle)... I never thought it bright though. I liked mine.

As I mentioned above, though. If I had speakers with tweeters, that were "a little over the top" in the treble area of reproduction....they would now be, more so.

You could try the Kav-500?...the three channel Kav goes for around $1,300-$1,400 used...pretty easy to sell, easy to ship if you don't like it, (50 lbs or so).

I paid $1,400 for mine, sold it a couple years latter for $1,400.

Thanks a bunch, Dave. That was very useful input. Just what I needed.