CM Caps

I opened one of my amplifiers (Chinese Image 34i). It has four CM-Cap coupling caps (each has a legend: "CM cap for audio MPT 630 VDC 0.47 uF J")

Any opinions on these caps and is there any reason for upgrading them by better caps?
Transl I work and live in China and I have seen and listen this amp. Nice looking unit and sound good too. The amp is about $700 new here and that's with their mark-up. So there is a good bet they didn't spend too much on the caps. Doesn't mean they are bad, but there is a very good chance you can improve on the sound of the amp. I've used Obligatoes and Mundorf Silver/Oil's in my Jolida amp and they both were fair superior to the caps that came stock. Sonicap makes some nice caps which are reasonable as far as caps goes at $8.00 a piece and there on sale now. Never used them my self but a lot of people like them. Have fun
Thank you! It is a nice amp indeed, especially because I upgraded it with vintage tubes. Still, it is too "polite" and does not have "slam" of higher grade amplifiers. I looked inside and saw more or less neat soldering job, but there is little space inside to install bigger and higher quality caps. I will ask my technician to have a look at it in order to decide whether it would be easy to solder new caps.
When you talk about slam I'm not sure if you mean more power? The caps will make things cleaner and they may give you more bottom end definition and allow you to see deeper into the music and reveal things you can't hear now. But it may not give you that extra slam you mentioned?

I don't think room is a problem in your amp. You can read some of the reviews on caps. Jon L did a very good one and so did Tony Glee. You can use their impressions but ultimately it's up to you.

Your amp is built by a company which calls itself Nelson Audio. Not sure why? But they make a full line of gear including speakers. I met the owner or the head designer in Guangzhou.

If you change the caps give them some time. My Mundorf Silver/Oil took a couple hundred hours to really shine. But I noticed a difference right away.
Why does the company call itself Nelson Audio? Because the designer's name is Nelson Ho? How do their products compare with Cayin, Mind-Da or Yaqin amplifiers?
That is a difficult question. I have heard the above mentioned products but not together. The Nelson Audio store in Guangzhou sells only their products. I did compare your unit to the Jolida 302 about 4 or 5 years ago in Beijing. I felt the Image 34 was a little more detailed than than the stock Jolida IMO but I knew that the Jolida could be modded to perform to a much higher level.

That along with the availability of schematics for the Jolida steered me to the 502. I also didn't know Nelson audio at the time and was worried about reliability. I went to the Guangzhou Hi-fi show in December and there was some nice stuff. I really like the Audiospace gear.
The Nelson Audio amplifiers are quite reliable. The 65i integrated amplifier powered with 6550 tubes is highly praised. My amplifier (34i) is definitely lower grade and I am not sure whether it is worth upgrading.