My Quest to Highend heaven with my first CJ AMP.

[Maze]

Hi everyone Maze here From Holland . Just want to introduce my system. and say thanks for having me here .

After having tons of stuff , wanted to try-out some CJ amp and got a CJ12 and to be honest it does NOT sound like expected.

Its dull , misses sparkle and spacioucenes . It sounds like a impedance mismatch but the CJ12 just has one Tap on it??? Anyone idea about what can be wrong here????

My system is :
Arc Sp11 mk2
Arc Reference phono
Airtight ATL10 passive Pre
Arc D70 Mk2
CJ12
Magico monitor MiNi
Marantz CD/Dac 12
Kimber 88 black Pearl.
Kimber KCAG
Amd few other stuff...
Weltempered ref TT with the Colibri

[admin]

Hi Maze,
Welcome to CJO. Great to have you with us.

First off, nice setup. You can tell that room gets used for some great listening sessions. Congrats.

As for the Premier 12. Not sure why it sounds "dull?" It's certainly a high quality amp. The first thing I would ask is whether both left and right channels sound identical? If not, maybe some component is going bad. Are the tubes new or have they been replaced? This unit is two decades old so we have to consider component degradation. Have you tried using the unit in another system to see if for some reason it is not blending well with the rest of your components (although I think that would be unlikely)?

[AnotherJohnson]

Simple. As old as it is, it’s time for tubes and caps.

Get CJ to recap with their proprietary Teflon.
Get tubes that are at least equivalent to Upscale Audio’s Platinum grade.

[Maze]

Hi Guys

Thanks for your respond , I did check the tubes before connecting to my system and everything looks good!

About the age of the amp I dont have a clue! It's my first CJ amp and was hoping for more ! I have had a bit of audio and know how my system can sound .

I just opened the bottom to see on what impedance it's wired and it looks like 8 ohm. That should make it a bit more lay back than the 4 ohm I'm using on my Arc amp but this is way to dark sounding.

Later I wil give the Airtight passive pre amp a try see if it makes a different.


Here some pictures of my QUEST to Audio Heaven in our old home .

[admin]

The Mini's are 4 ohm speakers. So I would start with that and make sure the impedance on the amp is set correctly.

Wow. Really cool room. I like how you have gone through a number of iterations with positioning. It can be difficult to get a proper setup in a room with limitations. It does take some experimentation.

[Maze]

Thanks Admin,

Correct , the Mini is 4 ohm. So have to see what to solder in the cj 12 to get it down to 4!
Some of the pictures you saw were I my old home.
In the new home I have a "mancave" . Ofcourse every room has its limitations . Mine is 3.2 meter by 5.5 meters and some sound treatment to make it better.

[Maze]

This is how my "mancave looks" with different setups and room treatment depending on my speakers and setup.

[AnotherJohnson]

FWIW, I’m pretty sure the Premier 12 was shipped set up for 4 ohm loads. CJ discourages changing to the 8 ohm taps unless you really insist on it because most speakers that are nominally 8 ohm have dips to lower values (complex impedance is frequency dependent, and not a constant single value).

Putting them back on the four ohm taps should move things in the right direction, especially for speakers that are nominally 4 ohm loads.

[admin]

Wow. That's some serious gear that has come and gone in that system. What turntable do you have in the 3rd to last picture (under the large acrylic dust cover?

As for the Premier 12, yeah, I would make sure it is set to the impedance of your speakers before anything else.

[AnotherJohnson]

If you search the forum for this

CJ output transformer cable color (2) (2).pdf

You should find a link from Roberto that gives the color code for transformer taps.

I was not able to copy the link here. Maybe Roberto or Admin could establish the link.

For 4 ohms
Yellow +
Gray. -

2 ohms could also be of interest
Yellow +
Orange -

8 ohms
Yellow +
Black/White -

I think someone reported that this color code is actually on the transformers.

[Maze]

FWIW, I’m pretty sure the Premier 12 was shipped set up for 4 ohm loads. CJ discourages changing to the 8 ohm taps unless you really insist on it because most speakers that are nominally 8 ohm have dips to lower values (complex impedance is frequency dependent, and not a constant single value).

Putting them back on the four ohm taps should move things in the right direction, especially for speakers that are nominally 4 ohm loads.

Thanks for the info , have to check the amp to see how its confogurated now. I think the owner said 8ohm! He had it on a pair of Avantgarde.

[Maze]

Wow. That's some serious gear that has come and gone in that system. What turntable do you have in the 3rd to last picture (under the large acrylic dust cover?

As for the Premier 12, yeah, I would make sure it is set to the impedance of your speakers before anything else.

Thank you,
I have had a few gear in the years. .

If you like turn tables than this should rock your world.

My best ever..TT... :::: Continuum criterium with the Airtight PC1 Cart on the ARC ref Phono and Kharma Exquisite speakers.

Ps.. the Tt your asking about was the Transrotor orpheo doppio.

[admin]

You can find AnotherJohnsons linked post here:

https://www.conradjohnsonowners.com/vie ... 500#p10500

[Maze]

If you search the forum for this

CJ output transformer cable color (2) (2).pdf

You should find a link from Roberto that gives the color code for transformer taps.

I was not able to copy the link here. Maybe Roberto or Admin could establish the link.

For 4 ohms
Yellow +
Gray. -

2 ohms could also be of interest
Yellow +
Orange -

8 ohms
Yellow +
Black/White -

I think someone reported that this color code is actually on the transformers.

Thank you , this should help!

Just opend it and this is how it looks internally.

Looks like im on 8ohm!

[AnotherJohnson]

That’s the 8 ohm set up.

[admin]

Yup. Switch it over to 4 ohm and let's see how it sounds.

BTW- your pictures are amazing. You've really had a tremendous amount of gear go through your system. Are you a reviewer or simply hard to satisfy?

[AnotherJohnson]

What do the cichlids think of the music? Does music sooth them? Are they from Lake Malawi?

[Maze]

Yup. Switch it over to 4 ohm and let's see how it sounds.

BTW- your pictures are amazing. You've really had a tremendous amount of gear go through your system. Are you a reviewer or simply hard to satisfy?

Tmx Admin, I have had my share of nice stuff. I dont do revieuw , its just hobby and trying to see how diffrent stuff sound.

[Maze]

What do the cichlids think of the music? Does music sooth them? Are they from Lake Malawi?

They dont mind the music , lol. They are from Malawi.


Today I tried some other pream(Airtight) to see what it does. It did a better job than the Arc , just not shure its my kind of sound.

[AnotherJohnson]

I used to raise Lamprologus Brichardi from Lake Tanganyika, but I’ve also raised pseudotrophius and haplichromes from Lake Malawi.

The L. Brichardi are incredibly beautiful ... and prolific when a pair have adequate space to feel at home. Any of these mouthbreeding species will provide excellent entertainment.