ARC 100 Mk11or Conrad Johnson 11a?

I have not heard that particular conrad-johnson, but the vt100m2 is one of my all time favorites. I've been very happy with the build quality, sound and support on mine.
Arc's tend to be more accurate and transparent, but conrad johnson's tend to be warmer with wonderful 'alive' midranges. I used to own the mv-50 which is a distant ancestor to the premier 11a. I thought the mv-50 was wonderful with my magnepan 1.6QR's.
Take care,
John.

Hi, I own ARC vt130 and have heard ARC100mkII at my house.
My experience with CJ is at dealer showroom.
They certainly sound different, but I don't think it is an "clear" upgrade. simply a sideways move ! ARC was very neutural, CJ was very relaxed and "great" midrange. I thought the VT130se was better than VT100mkII. More bigger, enveloping sound.
hope this helps.

How much power do you need? The ARC has more dynamics, more spacious soundstage, better bass, but its upper mid/lower treble bites a bit. The C-J is more seamless, finer textured, more midrange body, but sounds smaller/less powerful; should also be cheaper by 20-30% used. Are you only looking at tubes? Marsh A400s-pretty great for 200 watts/ch solid state.

I own the VT100 MKII and have auditioned the VT130 in my system. Suffice it to say, I did not feel it necessary to replace my ARC D115 MKII with the VT130. However, after hearing the VT100 MKII in my system, I sold the D115 MKII. I think that the VT100 MKII is a superior amp to the VT130. Period! Used with the 'right' ancillary equipment and cables the VT100 MKII can sound 'rich' in the midrange without being 'tubey' sounding. The VT100 MKII has greater treble extension and bass control than either the CJ IIa or the VT130. The CJ has a warmer, less transparent (darker?) tonal balance than the VT100 MKII which also has a magic midrange. In the final analysis, the 'better' amp depends on your system/room and personal preference.

Really, this is an apples vs. oranges comparison. As mentioned above, the CJ and ARC sound is about as different as you can get, and both are pretty much the models for their style. I suggest that you try and audition the ARC with your speakers and see which of the two amps speaks to you. I'm certain that one will very quickly stand out as a preference.

I upgraded my system last year and spent quite a bit of time auditioning both of these amps. In my case, it didn't take very long for CJ to stand out as a clear winner. Between the two brands, I found the CJ equipment to be much more emotionally involving, as well as being easier to listen to for long periods. To me, the ARC systems felt somewhat cold and lifeless. However, in every system I listened to, the CJ amps really seemed to be at their best when paired with other CJ electronics, while the VT-100 sounded good with a variety of preamps and sources. Just something you might want to consider when evaluating the two amps for your system. Anyway, it boils down to a personal preference, but it would certainly be beneficial for you to hear the ARC before you decide if swapping out the CJ constitutes an upgrade.

Happy listening...
Ken