Mayhem on AmRad 40 m. band

[Jez]

High end hi-fi would be more accurately described as High-Price Hi-Fi.

Conventional circuitry that works flawlessly is too boring, too hard to market. But stumbling across an old cache of nuvisters worked out pretty nicely for a certain Mr Michaelson back in the day. That's the thing - do something unusual, create a bit of excitement and a "story", sell stuff. Who cares how it measures and actually sounds... (not passing judgement on that particular example, but some of what you see today is really quite sketchy)

No harm in experimentation, of course. Should be interesting and fun. But there won't be gold at the end of the rainbow. We already found that with the bipolar transistor

You've basically got it yeah but I can't entirely agree with all of it.

As many will know I waged a one man war against audiophoolery for several years (and got myself banned from all the hi fi sites over it!). Magic fuses, enchanted speaker cables, snake oil coax and "grounding boxes" (literally a wooden box full of "earth" ie soil from the garden, with binding posts on it to which you "ground" your system. £500 - £4000. No I'm not making this up!), amongst other things were all given "both barrels" by me on a daily basis... which made a lot of audiophools very angry

However.... on mainly engineering led sites there is a tendency for people to take things way too far in the opposite direction! On sites such as this people think that all decent measuring amplifiers sound the same. They do not! (and that Quad 33/303, 44/405 are really good.... nope! Especially the pre amps which are poor).

Two units both measuring <0.01% THD and flat from 10Hz - 40KHz, good square wave performance, good damping factor, low noise etc can sound very different to one another with one sounding great and the other one grating on the ear. No one knows why. Which seems to get the backs up of people used to being able to correlate measurements with observed performance in all other fields of electronics. It simply doesn't work like this with hi fi. This is one of the main reasons it has kept my interest and fuelled my frustration since I was a young 'un and why I made it my career.

Bipolar transistors can sound great yes. As can valves. As can FETs and mosfets. But it's horses for courses and they can all sound different depending on how they are used. Square law V's exponential law of devices is just one facet of this (well covered by Baxandall many years ago... but only the technical side. He was virtually booed off stage at an AES meeting late in his life for his "everything can be measured and all decent kit sounds the same" rant which he delivered!).

Valves can often sound particularly good and with fairly simple circuitry. Yes of course there is audiophoolery surrounding this as well and many will (wrongly) say that valves always wipe the floor with transistors for sound quality and even that a single solid state device in the signal path can ruin the sound! (valve rolling I find particularly weird!). Strange then that all audio is not unlistenably awful with all those NE5532's in the mixing desks that most recordings have passed through!

But yes if the rod pentodes have the sort of virtually non existent microphony, very low noise and fine linearity hinted at then they could possibly perform very well in audio gear... and yes the punters are likely to go daft for something "new and different"

(no I can't get the quote thing to work with my browser and computer. There is no "end on quote" to start beneath on my outdated browser and I tried putting several empty lines between the quote and my reply as you can see but still no difference. I'll just keep adding quotation marks)