AudioAficionado.org  

Go Back   AudioAficionado.org > Audio & Video > Tubes & Valves

Tubes & Valves Upgrades, Spares & General Comments

Reply
 
Thread Tools Display Modes
  #1  
Old 11-03-2019, 09:02 AM
n_brio n_brio is online now
Member
 
Join Date: Oct 2018
Posts: 49
Default Nos amperex/Philips tube lights up

I did find 4 matched Nos philips/amperex holland made fom 1963 - 1969 here in sweden to a really good price so i brought them and just put them in.

But when i start the pre amp (C500T) the tubes flashes like a normal light bulb for 1 sec and then turn green. is this normal? It did not do this with the gold lions.
Everyting else is normal
Reply With Quote
  #2  
Old 11-03-2019, 09:00 PM
W9TR's Avatar
W9TR W9TR is offline
Senior Member

 
Join Date: Sep 2009
Location: The Neutral Zone
Posts: 3,497
Default

Your tubes are fine. Older 12AX7 variants made by Phillips or under license from them exhibit this effect - a bright filament on startup and then dimming down to normal as the tube warms up.

Newer 12AX7A tubes have a more controlled startup and don’t exhibit this behavior. The A suffix stands for controlled filament warmup.

Tom
__________________
Main System:
Amati Futura Mains
Amati Homage VOX Center,
Proac Response 1sc Rears,
Three MC2301's for L,C,R
MC 602 for the rears
C 1100, MX 151, MCD 1100, MR 80
Nottingham Dais with Sumiko Palo Santos Presentation
SurfacePro 3, JRiver, WW Starlight Platinum USB, Schiit Yggdrasil, Benchmark DAC3 HGC

MX 151, OppO BDP-95, JVC RS-500 DILA projector, 106" diagonal Stewart Luxus Screenwall Deluxe with Studiotek 130 G3 material.

Lake House:
Ohm F, MC 275V, C2300, MR 77, Rega P3

OnDeck:
McIntosh MAC 4300v
Reply With Quote
  #3  
Old 11-04-2019, 09:08 AM
n_brio n_brio is online now
Member
 
Join Date: Oct 2018
Posts: 49
Default

Ok thank you!
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Audioaficionado.org tested by Norton Internet Security

All times are GMT -4. The time now is 10:21 AM.



Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
©Copyright 2009-2019 AudioAficionado.org.Privately owned, All Rights Reserved.
Audio Aficionado Sponsors
AudioAficionado Subscriber
AudioAficionado Subscriber
Inspire By Dennis Had
Inspire By Dennis Had
Harmonic Resolution Systems
Harmonic Resolution Systems
Wyred4Sound
Wyred4Sound
Dragonfire Acoustics
Dragonfire Acoustics
GIK Acoustics
GIK Acoustics
Esoteric
Esoteric
AC Infinity
AC Infinity
JL Audio
JL Audio
Acoustic Sciences Corportation
Acoustic Sciences Corportation
Legend Audio & Video
Legend Audio & Video
Audio by E
Audio by E
Canton
Canton
Bryston
Bryston
WireWorld Cables
WireWorld Cables
Stillpoints
Stillpoints
Bricasti Design
Bricasti Design
Furutech
Furutech
Shunyata Research
Shunyata Research
Accuphase
Accuphase