Description
This is a pair of NOS testing Siemens Halske CCa made in Germany. It is the preferred grey shield version. The properties of this tube are legendary and widely known. I refer to the many threads on the web for more information. The tube is thoroughly tested and it has excellent electrical values (note test results below). NOS testing tubes!
Siemens produced a very limited number of these beauties.
Note: I also offer a Telefunken CCa pair; a famous tube also!.
The tubes have the typical E88CC plate structure. The pair has very nice test values that match the factory specification well.
Sonics
Excellent preamp valve, low noise, very smooth extended highs, very good in phono stages.
CCa / E88CC: balanced and smooth sounding with liquid midrange, recommended!
Test results*
| Valve 1
V427 |
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
15,2/ 15,2 mA
11,7/11,4 mA/V OK |
= NOS
= NOS
|
| Valve 2
V426 |
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
14,9/ 15,1 mA
11,2/ 11,5 mA/V OK |
= NOS
= NOS
|
Where NOS is : Ia = 14,2 to 15,8mA, Gm= 10,5 to 14,9 mA/V.
* For test methods and factory specification read the tube testing page.
Short description
| Tube type | CCa |
| Quantity of Tubes | One pair |
| Brand | Siemens Halske |
| Manufactured in | München, Germany |
| Date codes | no visible date codes |
| Plate Construction | “Spangitter” |
| Getter Construction | 0-getter grey shield |
| Print Condition | see pictures |
| Box included | replicate Siemens box |
| Equivalent tubes: | E88CC, 6922, E188CC |
| General test results | NOS |
