Kharma Matrix MP 150 issues???

hi Jimbox; first...very nice system; i'll bet it sounds excellent.

i would strongly recommend that you disconnect your speakers from your amps temporarily. the reason is that the ceramic mid-range of your wonderful CRM 3.2's is relatively fragile and those 'pops' could easily shatter them. i use to own Kharma Exquisite Reference speakers with the same drivers and i shattered three of them over the three years i owned them.

next find another speaker (it could be just about anything) and connect it to the right hand Matrix MP150. play the music again and see if you get another 'pop'. if you do then connect this speaker to the other MP150 to see if that side pops. if it does not then switch interconnects with the right and left output of the ART preamp and then see if the right MP150 'pops'with the left input of the ART. you simply need to isolate the problem to the one amp before you go any further (but without blowing up your ceramic driver).

obviously; if you don't get a 'pop' with the left input from the ART your problem is not the amp. you then need to isolate the right channel of your preamp; followed by the right channel of your source.....until you determine the source of the 'pop'. i do agree that the amp is the likely source but not for certain until proven. a 'pop' from your ART could trigger the protection circut of the MP150 and shut it down. the ART has those nasty tube thingys.....which when going bad can 'flare' or 'sputter' and could be your problem. this would be the 'DC' (direct current) your friend speaks of.

don't assume anything.

once you isolate the problem to the right hand MP150 e-mail your dealer or Kharma directly; Kharma was always very helpful to me. a class 'D' amp is pretty simple but you may have some sort of 'part failure'.

Hi Mike,
I really apprecitate your support. I am always on Agon and happen to see your system. What a wonderful dream you got there!!! It reminds me of my fathers system in Asia. Here is what i find below this morning.
I find out my Cj ART pre-amp lower chassis tubes are not lighing up. Here is what i did. I change all tubes from the bottom chassis to the Top chassis to test if the tubes were ok? Yes, there fine, thank god! I also check the fuse inside the art and its ok. Does this sign means, my lower right side channel is done? The light still stays on, but not the tubes, and no sounds.

However, if the preamp is leaking DC? Does this mean i need a module for DC filtering before the input? Does kharma make that? Or, maybe i have change my preamp better to work with my Mp-150?

hi Jimbox; thanks. your father's system and room is really on another level beyond anything i have ever seen.

i assume from your description that you have determined that the 'pop' originated from the right channel of the ART? is that correct? since the ART is a true dual mono design; the left channel should be working fine....is that correct?

are the tubes in the lower chassis of the ART for the right channel? that is not clear from your comments?

if so; and you have then switched those bottom tubes into the top and they all work.....you likely have some sort of failed part in the right channel. i am afraid i have no further thoughts about what to do to for an easy fix. you really need to contact Conrad Johnson or your dealer.

the preamp is not 'leaking' DC; but the 'Pop' might contain DC which can occur when there is a 'short' someplace which can be the result of a failing part. one guess about why might be that once this failing part reaches operating temperature it shorts out.....this 'pop' resulting triggers the protection circut in the MP150. the POP may just be a very loud sound and not contain 'DC'....but non-the-less it triggers the protection circut.

you can likely thank the design of your amps for preventing damage to your speakers. in essence; the amp is acting as the 'filter' you mention.

you must fix the ART before it can be used.....at least as i am reading your repsonse to my initial post. hopefully the 'fix' will be something simple.

in your efforts to isolate the 'pop' did it occur again? if so; how long after you turned on the ART did it happen again?

also...are you sure there is only one fuse on the bottom of the ART? maybe consult the owner's manual.