Hacker News Reader

Comment by nlh | Hacker News Reader

I’m a long-time ham (DE K2KD) but one thing I missed out on was the fun of building a mega vacuum tube amplifier.

I remember fondly gawking over things like the 3-1000Z tubes and dreaming of having an amp like this on my desk:

https://www.youtube.com/watch?v=k9nsRZKvLtg

I also came after the [valve|tube] generation but when I was a kid I similarly felt left out. So I dug out an [ECC83|12AX7] from my Dad's store room, found a high voltage PSU and hooked it up. Once I had made a circuit that proved it would act as a gate, I turned it off and that was the end of my interaction with thermionic devices. Still glad I did that though.

The 12ax7 and ecc83 / el84s are still commonly used in guitar amps. It’s fascinating how different manufacturers versions of the 12ax7 affects tone and transients.

Have there been made digital models that mimic the sound characteristics of these tubes based on descriptions of their mechanics? That might be an interesting project: emulate different manufacturers tubes based on the exact physical differences between them. Tubes are very interesting, they are amplifiers, switches, resonators, diodes, microphones, sources of interesting particles and even speakers when used creatively.

Someone did this a few years ago but I can’t find the link. It would pass in a double blind test but I suspect if someone realised it was a DSP then it would instantly be unpopular.

Most of the tube sound actually comes from the terrible performance and lack of linearity of the tubes.

I understand the point of view, but aside from the analogue vs. digital debate of passing double blind tests of final output, in my personal experience the real big difference is in real-time when the sound is being produced. The subtleties of latency and transient responses, microphonic feedback, and distortion while playing are what make tubes preferable for audio. I suppose it’s not unlike comparing driving a Tesla and a rear-wheel drive combustion engine car - the outcomes can certainly be similar, but the process is vastly different.

I think they sound terrible so it’s definitely subjective :)

There are a lot of electronic guitar effect pedals that try to emulate different types of tube amps. Some do a pretty good job.

Annoyingly people seem to rob them out of other equipment destroying it in the process.

Reply on news.ycombinator.com