1970s Design Indulgence

Paraphrasing BBC Science Focus "the electromagnetic wave rippling through the electrons will usually be around 90 per cent of the speed of light"

So will one channel connected by 6 inches of wire sound different to the other channel connected by 2 inches of wire?

It depends on the frequency, yes, but at the frequencies of audio and right up to the stability corner frequency of a typical audio amplifier (1MHz to 10MHz) it will run at ...

Well, let's take the lowest frequency of light as 400,000,000,000,000 Hz and 90% of that is 360,000,000,000,000 Hz and so

10MHz being 10,000,000 Hz, so 360,000,000,000,000 / 10,000,000 = 36,000,000, and as a decimal fraction 0.000000028th.

So, at 10MHz the electromagnetic wave travels 0.000000028th slower than the speed of light.

So, at audio frequencies just add a few more leading zeroes, and if you can hear it, then you need psychiatric help.

But obviously, 6 inches of wire is open to more interference than 2 inches of wire, as all wires are also antennas. But it depends on the direction of that interference and if it's straight down onto the wire, it receives 100%, but we're talking about frequencies, so on the opposite cycle, if the wire has the chassis below it, then it receives 0%, so even an open chassis attenuates interference by half.

Common sense says that you place the thing away from strong magnetic wave generators.

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As 45 years ago I didn't bother checking. I'd just had enough of the soldering shakes - the two pairs of glasses - the awkward Chinese wire, and the awkward Chinese plated pins!

I gave it a good look over, it all seemed to be there, and thought "sod the test gear", and went and plugged it in. Turntable connected, output to power amp, switch on and hope.

Well, it works (so far). Swing the balance left and the left speaker goes louder than the right speaker (and vice-versa). Tone controls work. Tone cancel works!

45 years in the making. I'm exhausted and feel like calling it a day (perhaps?)

The vinyl input sounds louder that its 38dB gain would suggest, and digital (from the Majestic fixed output sockets) seems to have a bit more "meat" - perhaps I should say both seem a tad warmer than you'd expect for solid state. Then again, this is discrete transistors with lower open-loop gain than op-amps.

The 35dB attenuation followed by 35dB gain on the more sensitive line input doesn't seem to have taken anything away. The source output impedance has zilch effect on the preamp input, and this is due to the attenuation. The preamp simply sees a small driving resistance - this being around 800 ohms.

It will take a few days for the electrolytics to bed in. Often you get a fuller sound with brand new electrolytics, which then "give" and the "consistency" improves - the sound becomes more realistic.

Timing is fast enough, but should improve, and perspective or soundstage depth is becoming deeper, making fade-outs sound like the stage is receding into the distance.

Clicks and pops as well as "groove distortion" are well back with music to the fore.

Maximum output noise is a bit high indicating a hum-loop. It isn't induced noise from the transformer as I switched the mains off and it remained until the smoothing cap discharged.

Perhaps the 10 ohm resistor has to be 100 ohms and the cap 10n instead of 100n. Or, perhaps it's the cap and it just needs the 10 ohm resistor. These are the joys of grounding.