Valves. Brimar Mazda ECC83 grey ladders plates NOS 1962-1972

Sorry to divert from your specific question, but I am trying to imagine where you would use a 12AX7/ECC83 in a CD player. Typically, CDPs that use tubes, use them in a capacity that would not be well suited to an ECC83.  Are you trying to replace "like with like", or are you experimenting with changing the tube type, as well as the tube brand? If you would divulge the name of your CDP, that would help.  Thanks.

Thanks a lot for the answers. The name of the Cdp is Lua Appassionato, famous player and H Lua is an authority and I m not afraid that he could do wrong things. Last year he used Mullard Ecc83 valves,  now for the actual upgrade he use the Brimar Mazda grey plate valves.

background of my question is a Test from watford valves, Derek Rocco. He Tested many valves, also the Brimar cv4004 and the Mazda greyplates, and that seems to be valves with a different sound. So there seem to be differences between Birmar valves and that is the reason I asked for the sound of theMazda ecc83 greyplates. Does anybody know this valves?

I have a doge 8 pre, and Lua is the name for doge in Germany...In fact it depends a lot of your taste and the CD player.
On my pre the Mazda grey plate was common, I prefer the silver plate but in Somme occasion people may found it too bright.
For me the basic Mazda grey plate was lacking high and air.
I finally settled on philips heerlen factory which have a lot of air.
You can find cheap mazda on eBay to try.
There is probably a difference between brimar and Mazda grey plate but it is not night and day.
For 12 at7 I found the Mazda to be great but lacking high with some electronic but with a good 3 d on the soundtage.

The Brimar cv4004 is a boxplate which is a military spec valve. It has a very different internal structure than a grey plate and will sound different. I have the boxplates and they have sweet mids with smooth extended highs.

There are different versions of the Mullard ECC83; short grey plate, longplate with square getter, longplate with O getter. They all have warm sonics, with the longplates having a better soundstage and deeper bass. 1950’s would be the best.

If the Mazda has grey ladder plates it will sound very different than a CV valve.

There is very little tech info on the net about the Lua, but it does seem to be a very unusual piece, apparently using tubes for some functions other than as an output buffer, where the 12AX7 would not be a good choice.  Probably the 12AT7s serve that purpose.