Tubes, glow and tube amps

For genuine glow you’d need to run a jillion volts through the tubes, and use functional tubes. A hot death trap with no sound?

These display items are themed LED lamps, but surely do fit the décor of some rooms. If you want to display 300Bs and KT88s, you might buy (or be given) worn out tubes and be able to put them in this type of display socket. It depends how they are constructed. Some of the builders may do a proportional custom build for you too.

A lot of tubes don’t really glow very much, you’d be hard pushed to even see the filament is glowing in my 2A3 amp during daylight hours. Even the 845’s in the Viva which are like light bulbs compared to most tubes, the glow isn’t bright in daylight.

1 Like

The lack of glow might be fixed with strategically positioned LED or neon mini bulbs.

1 Like

16 Likes

Over the years I’ve actually grown to prefer the tube longevity of a dimmer tube over the lack of visual aesthetics. And then even shielded tubes to further decrease noise, but now they just look like ugly metal tins :joy:

2 Likes

Might as well put the tubes INSIDE the metal boxes like STAX does.

2 Likes

It’s what most tube pre amps do. Not that 12AU7’s are particularly attractive to look at.

Ah, so it’s exaggerated in most audiophile ads?

2 Likes

Pictures taken in low light conditions to emphasize the glow for the most part.
Many tubes the construction hides the heater which is the glowy bit, because its job is to heat the cathode, and wrapping the cathode around it is more efficient.
Some older tubes have constructions that expose the heater more, and some use thoriated tungsten filaments and glow a lot more.

KTC’s picture of his Horizon above is a pretty reasonable indication of the ammount of glow most amps put out in with limited direct light, most of the images here are obviously real but taken to emphasize the glow.

2 Likes

In addition to what @Polygonhell said, some amps have LED lighting in the sockets. LEDs generally make the bottom of a tube brighter than any other portion, but the heat and function actually comes from the middle region. AFAIK tubes do not glow green either (but they can have genuine blue in the middle):


KT88s – not LED lights:

12 Likes

I would pay double for a pair of vintage RCA 2A3s that did this. I suspect that anyone who has such a thing isn’t parting with it.

The filaments on the top of mine barely turn orange.

10 Likes

14 Likes

Are you referring to RCA dual plate 2A3 tubes?

7 Likes

What tubes you running? I am not a tube identifying wizard lmao

Sylvania 5U4G, RCA 2A3 (black plate, spring top), and a Voskhod 6N1P-EV.


McChanson Ultimate Mini, Phillips 1963 EL84 output, Ken Rad 6C5 driver, Mazda EZ81 rectifier.

8 Likes

That’s a very intriguing amp David, how did you even find out about it or its builder?

I’ve never heard of it (or him), so of course had to Google it. An Australian amp to boot? I’d be interested in your impressions of it, and how you came to have one. It’s definitely an amp off the “beaten track”…

3 Likes

Thanks for asking Jonathan.:pray: I was looking for an amp with a bit more tube flexibility than my LTA MZ3, a bit less costly. I also had a bit of small builder fever.:flushed::thinking: I came across a multi hundred posting thread on McChanson amps on head fi, and was intrigued by 1: the uniform accolades, even easily driving a Susvara 2: the tremendous variety of tubes not only supported but uniformly sounding excellent and 3: the variety of pre build out customisation options. Order to delivery time was less than 2 months. Price for mine was about 1/3 of the cost of my MZ3, and it punches right up there with it, in some ways better due to tube options.
I am very happy with the performance, and choose to listen to it 2/3 of the time. It is a bit darker in the mids and fatter in the bass than the MZ3, which I still enjoy.
I use it with a ZMF Caldera and Verite Closed, occasionally a DCA Aeon Closed X.

8 Likes

7 Likes