Ayon CD5S Tube Replacement


I I have recently purchased the above in excellent condition and very happy with the outstanding performance.
The improvement over all my previous CD players is amazing with drastic improvements to resolution, imaging and superb mid/range with another octave of bass!

This player allows streaming via USB and the results are equally impressive highlighting the performance of an exceptional DAC.

The CD5s came  boxed and with the Ayon User Manual  - that did not provide any useful information regarding tube replacement.  I expect the 6x4 rectifier tubes may need to be refreshed - as I notice after turn on the display pulses for a while but becomes stable after about 15 minutes.  I am not sure how many hours this machine has done so I would prefer to simply change the rectifiers_

Can anyone explain how to remove the top plate of the CD5s  to  enable tubes to be replaced as this is NOT obvious and secondly which brand of tubes work best for the power supply and signal path (6h30)?

128x128warmtone
I am an owner of  AYON CD-5 (bought used, but prob had very little hours on it, looked brand new), and it is really an amazing player (or DAC, as it used 80% of the time). I had the same question, and found on AYON S-3 manual on page 40 instruction on opening the unit, which has the same case as CD-5. But video indeed will be better.
Now I am thinking what tubes I should (and should I) replace. What tubes are actually inside - is it known?
It specifies (4) 6H30 and (4) 6Z4 in the manual. The 6Z4 are Chinese made tubes with very few substitutes. They are pretty inexpensive. I was experiencing some tube noise in mine and changed them all out. I used Electro Harmonix gold pin 6H30s, so the complete tube change out was less than $200. I can't say if NOS 6H30s would be an improvement over the EH, but I am satisfied with the result. 
@csmgolf 
Thank you for this info!
When you replaced tubes, what 6H30 were originally in? Sovtek?
It has been several months ago so I am not 100 percent certain, but I believe they were Sovtek. They were certainly nothing special (i.e. pricey NOS tubes). Knowing how it sounded with the inexpensive factory tubes, I had no problem going with the EH to replace them. 
@csmgolf  thank you again! Did you use regular EH 6H30Pi, or "selected by vendor" (i.e. matched triodes, low microphonics, etc)?