E88CC Valvo (CCa) Matched Pair NOS condition, same date codes! 1961 ** v3/6

Description

E88CC Valvo (CCa) Matched Pair NOS condition, same date codes! 1961 ** v3/6
Highlights:
Valvo
Red print
Heerlen production
testing NOS
matched and balanced pair
grey shield
nice print
Note
: my tubes are often not the cheapest.
But is
very hard to find better tubes !
E88CC twin triodes are very popular for audio applications. The most sought after makes are from Telefunken ULM, Philips Holland, Mullard UK, Valvo Hamburg and Siemens Munich.
Description
This
is a pair early VALVO RED LABEL E88CC tubes made by Philips in the Netherlands (Heerlen plant).  Tubes have grey shield and 0-getter. Very strong tubes with matching systems. Very reliable, long life and low noise version of a ECC88 tube only used for military or postal purposes.
The properties of the Valvo/Philips E88CC are legendary and widely known. I refer to the many threads on the web for more information.
Both
tubes are manufactured in 1961.
The tubes are thoroughly tested.
The matched pair has strong test values that match the factory specifications very well and and both tubes have balanced systems.
See  test results below
.
Note: in another ad I offer a Mullad
E88CC
pair; a famous tube also!.
The
etch
codes
7L6
Δ
1J2
on the glass
indicate that both tubes were manufactured in
1961
in the Heerlen plant in Holland.
The tubes have the typical plate structure of the
E88CC
(frame grid).
The pair has excellent test values that match the factory specification very well and balanced systems.
This pair is a real jewel, so please excuse the high price.
Sonics
Excellent preamp valve, low noise, very smooth extended highs, very good in phono stages.
E88CC: balanced and smooth sounding with liquid midrange, recommended!
Factory Specification
The emission value for a new E88CC is:
14,2 - 15,8 mA
The transconductance value for a new
E88CC
is:
10,5 - 15,0 mA/V
(for factory specification see last picture)
Test method & results
Philips, Mullard, Philips, Telefunken and other manufacturiers also describe how to measure the tube data of an E88CC. And they supply also the end of life criteria for E88CC tubes that were measured with this testing method. These criteria are more strict than those used for traditional tube testers. For example: the average anode current of a new E88CC is 15 mA and the end of life is reached when this value is lowered by 10% (13,5mA). In many tube testers the end of life is indicated when the initial value has lowered by 40% (9 mA) or more.
For our tube tests and ratings of the E88C) we use the testing setup and the very strict NOS and end of life criteria that are specified by the manufacturers (Telefunken & Siemens).
Tested with:
AVO CT-160 (Dutch army tester), AVO Valve Data Manual 23rd edition 1981, Utracer3+, Philips 1532, RFT stabilized power supply, 2x Korad KA3005P programmable power supply and 2x Keithley 2700.
Gas and shorts tested with: AVO CT-160 (Dutch army tester) Setup: AVO Valve Data Manual 23rd edition 1981.
Ia is tested with the official Telefunken/Philips/Mullard E88CC test setup: Va = 250V, Vba = 90V and a 680 Ohm cathode resistor.
Look for a detailed description of testing methods on the site:
tubes4hifiaudio.ctpu.nl/
tube-testing-quality-control/
Measurement after 10 minutes stabilization.
The measurement data below show that both systems are
matched and balance
d.
And fulfill the factory specs of a new/NOS tube.
Valve 1
(V3)
System 1/2
Ia (plate current):
14,6 mA
/
14,8 mA
=
NOS / NOS
Mutual conductance:
13,5 / 14,3  mA/V
=
NOS / NOS
Gas test, Shorts test:
OK
Valve 2
(V6)
System 1/2
Ia (plate current):
14,9 mA
/
14,9 mA
=
NOS / NOS
Mutual conductance:
13,2 / 13,3  mA/V
=
NOS / NOS
Gas test, Shorts test:
OK
(
factory specification see picture
)
Summarized description
Tube code:
E88CC
Brand:
Valvo
Manufactured in:
Heerlen, Holland
Date Codes
:
7L6
Δ
1J2    both!
Production date:
1961
Plate Construction:
frame grid;
grey shield
Getter Construction:
round halo getter
Print Condition:
new; see picture
Box included:
Generic
box
Equivalent tubes:
E88CC, CCa
General test results:
t
est new
Quantity of Tubes:
2; one pair
Please study photos carefully; what you see is what you get! A
sk any questions before bidding. Thanks
—————————————————————
Shipping
I
ship
worldwide
.
Shipping costs for countries
outside Europe, if not shown,
are supplied on request.
Shipping on buyer's risk
.
Product is sold as is.
Private sale.
Test results may vary on your test equipment.
I cannot offer any guarantee or warranty.
I will pack the item very carefully.
Shipping with tracking.
If you prefer insured shipping or another shipping option please contact me !
Payment
Bank transfer preferred;
Payment within 5 days after auction ending.
We are located in Holland (Europe) so for customers within the Eurozone the easiest and cheapest way to pay is via an international bank transfer (IBAN).
Paypal outside the EU
.
Cus
tomers
outside the Eurozone can pay with PayPal.
We are not a company, shop or other business. We therefore cannot accept any other form of payment like credit card etc. Sorry!
Sellers Note
I will offer a full take-back with
complete refund
of the purchase price within 14 days after delivery if the product is dead on arrival!
Conditions for a take-back: Item must be returned unused (except a short listening test, of course) with functioning heater filament and visible undamaged. Shipment back to me will be made on buyer’s risk only. Money-back transfer for take-back will only be made via PayPal after the tubes safely arrived back here.
_gsrx_vers_841 (GS 7.0.16 (841))