Beschrijving
The Telefunken ECC803S is the best ECC83 ever made!
A Telefunken ECC803S tube made in Ulm Germany. In original box; please see pictures and test data!
I personally opened the foil around the box for assessment of the specs! (12 July 2026)
The printed code U0208501d on the glass indicates that the tubes are manufactured in the same date in the Ulm plant in Germany. The tube has the typical plate structure of the Telefunken ECC803S tubes (frame grid) and of course the gold pins and the diamond bottom.
The tube is thoroughly tested. And has excellent electrical values (note test results below). The test values match the factory specification very precisely and both internal systems are balanced.
The tube is a real jewel, so please excuse the firm It fully justifies the high costs. Telefunken produced a very limited number of these beauties.
The ECC803S will bring the real instruments and orchestra to your room!
Sonics
The sonical properties of this tube are legendary and widely known. I refer to the many threads on the web for more information. Superior preamp valve, low noise, very smooth extended highs, very good in phono stages. ECC803S: balanced and smooth sounding with liquid midrange, and extremely natural; recommended!
Quotes from the web:
- These tubes are just pure silk, rich and warm, and so perfectly quiet its amazing.
- Telefunken ecc803s was rather special tube in some aspect. It was extremely quiet and detailed tube better than any other ecc83 tubes in my collection.
- Holy grail tubes. Good investment, these tubes get more extinct every year!
Test methods & results
The tube is tested with official Telefunken test set-up. Test methods are outline on the Tube testing page, for test conditions see Category Page.
The measurement data below show that the tube is in NOS condition.
| Valve 1 | Ia (plate current): | 1,74 / 1,79 mA | = NOS / NOS |
| V396 | Transconductance (Gm): | 1,80 /1,83 mA/V | = NOS / NOS |
| Gas test, Shorts test: | OK |
The measurement data show that both systems of all tubes are matched nicely. The test results fulfill the factory specs of a new tube.
(Telefunken factory specification see picture)
Summarized description
| Tube type | ECC803S diamond bottom |
| Quantity of Tubes | One tube |
| Brand | Telefunken |
| Manufactured in | Ulm, Germany |
| Date code | U0208501d |
| Plate Construction | “Spangitter” |
| Getter Construction | Halo getter |
| Print Condition | Excellent; see pictures |
| Box included | Generic Telefunken box |
| Equivalent tubes: | E83CC, ECC83, 12AX7, CV4004 |
| General test results | NEW |
Please read our test and shipping policy before buying !
