Amp upgrade ?


I have a handful of amps in mind that I would like to upgrade to but I can't decide, #1,pass aleph 1s #2,Krell KSA 250 #3,Bat vk-500 #4,Sim w-5 #5,Mark lev 23.5 my current system is B&W 804 pre is audio research sp 16 cd player sony scd-1 I have heard all of these amps but in different system configurations even though some are much older than the others I think the krell and mark are still good units.
paulficarella
For less than half the money, I chose the BAT VK-500 with Batpack option to drive my Thiel CS 6 speakers. I considered the ML and Krell amps, but don't think spending two or three times the money would have resulted in that much better sound. My pre-amp is an ARC SP9 Mk II.
I agree the bat or the sim w-5 lae is still a very good choice both build like a tank and with the bat pack the power reserve is huge, I don't want to change my pre amp I think the sp-16 is still good I run it with a bryston 4 bst it sounds pretty good but not great, my brother has a krell ksa 100 the pure class a and it surprisingly sounds better than my bryston I have his krell right now and he has my bryston I don't want to give it back , anyway any suggestion would help thanks.
I am still breaking in the Modwright SWL 9.0 Signature model (new caps). So far it's incredible, I hooked up the Levinson No. 27 (paid $1400 local) to my Aerial model 6's. I am pulling the 23.5 and have decided to bite the bullet - sending it back to Harmon for caps and anything else it needs.

If there is an amp out there for $700 that equals the No.27 I am all over it. I will check with my local used audio store in Portland (Echo Hi Fi) and see if he has anything from BAT for demo. I thought I saw something up on the shelf the last trip in. I have tried a few Krell amps over the years but not with the Modwright. I may try that for comparison as well. It's nice to have a local guy that lets you demo equipment in your house. I read a post a week or two ago that said there were issues with running a tubed linestage with certain Krell amps (FPB?) and there where jumpered caps that had to be put in-line before you could run a tube linestage. The caps caused a degraded sound. If you didnt run the caps you risked damaging the amp.

Anyone have any info on that?