E88CC matched quad SQ Philips Heerlen 1971 NOS/NIB

Beschrijving

This quad Philips E88CC SQ tubes is made by Philips in the Netherlands (Heerlen plant).

These Special Quality tubes have a grey shield and halo-getter. All four tubes are manufactured in 1971 (in the months: may, may, july and november). This very reliable, long life and low noise version of an ECC88 tube which is mostly used for military, professional or communication purposes. The properties of the /Philips E88CC SQ for hifi applications are legendary and widely known. I refer to the many threads on the web for more information. 

Two tubes are new in original Philips factory boxes (NIB) the other two tubes are assumed to be unused (NOS). The tubes are thoroughly tested. The quad is matched very well and all four tubes are internally balanced. The specs of the quad match the factory specifications extremely well. See test results.

Sonics

Test results

 The measurement data below show that the tubes are matched (tube to tube match) and internally balanced. Tube to tube match and internal balance for all tubes is better than 5%. 

Valve 1 V19	Ia (plate current): Transconductance (Gm): Gas test, Shorts test:	14,7 /14,9 mA    12,9 /12,9 mA/V OK	=  NOS / NOS =  NOS / NOS
Valve 2 V45	Ia (plate current): Transconductance (Gm): Gas test, Shorts test:	14,6 /14,7 mA 12,5 /12,8 mA/V OK	=  NOS / NOS =  NOS / NOS

Valve 3 V149 (NIB)	Ia (plate current): Transconductance (Gm): Gas test, Shorts test:	14,6 /14,8 mA    12,0 /12,2 mA/V OK	=  NOS / NOS =  NOS / NOS
Valve 3 V151 (NIB)	Ia (plate current): Transconductance (Gm): Gas test, Shorts test:	15,0 /15,2 mA 12,4 /12,1 mA/V OK	=  NOS / NOS =  NOS / NOS

Test methods and reference values are outline on the Tube testing page.

 

Summarized description