Consider Connectors

“God is in the detail” – Ludwig Mies van der Rohe (et al)

Sometimes it’s necessary to re-examine the little things, the forgotten details.  Try to dig out the last 10% improvement.

Consider amplifier and loudspeaker connectors.

We know that music signals are alternating current, AC not DC – swinging positive/negative.  We know also that “current in a conductor resides at the surface at high frequency” (Prof. Malcolm Hawksford, HFNRR Aug 1985): Continue reading

Kenwood L-07D tonearm

This extraordinary tonearm was fitted to the Kenwood L-07D turntable, the legendary flagship Direct Drive turntable manufactured by Kenwood from 1979-83.

This was the halcyon decade or so, when Japanese hi-fi was at a peak of industrial and electronic design and engineering.

Those were the days when analogue hi-fi was at a high point, with many Japanese companies participating and leading the innovation.  Sadly, some of those great names no longer exist – eg. Fidelity Research, Sansui, Stax, Supex, Coral, Grace, Micro Seiki,…. Continue reading

LOUNGE AUDIO LCR phono preamp – Pt 2 LCR Gold upgrade

It’s been over 2 years since I purchased a Lounge Audio LCR phono preamp (US$300).

I was keen to investigate LCR phono EQ and possibly incorporate LCR EQ into my own Phi-42 vacuum tube DIY phono stage.

I shipped my Lounge LCR (MkI) back to Lounge Audio (Robert Morin) in California, for upgrading to LCR Gold specification (plus some extras).

The results are outstanding. Continue reading

TECHNICS SP-10MkII turntable – Pt 2

The Technics SP-10MkII turntable’s platter (yellow) is 2.9kg cast aluminium and is screw-fixed down onto the sub-platter rotor of the Direct Drive motor.

A ring magnet (red) is attached to the inside of the rotor.  The motor stator coils are fixed onto the motor bearing base below (green).  This bearing base is also cast aluminium and is attached to the turntable top chassis frame (green), with 4 small M4 screws.

If you examine the Technics SP-10 in detail like this, you can see that there are things that can be improved for potentially better performance. Continue reading

TECHNICS SP-10MkII turntable – Pt 1

The Technics SP-10 Direct Drive turntable was manufactured by Matshushita from 1970.  It had 33/45/78rpm speeds and superb technical specifications for speed accuracy and stability, wow and flutter and rumble.

The MKII / MK2 version was manufactured from around 1975 I believe, until at least 1987.

The SP-10 was supplied as a motor unit without tonearm/s, for studio or commercial use.  Continue reading

Street food – TAIWAN

Taiwan is known for ‘street food’, but ‘snack food’ is a better description for what is found throughout all of Taiwan.

Taiwanese cuisine is most obviously Chinese cuisine, but influenced by the Japanese, who ‘ruled’ Taiwan for 50 years from 1895 to 1945.

Japan constructed and organised much of Taiwan’s civic infrastructure and has greatly influenced public behaviour in general – something that is still much in evidence in (orderly and efficient) Taiwan today. Continue reading

AZTEC CAMERA – High Land, Hard Rain

Now 35 years since release (1983), I still love this album

Aztec Camera (ie. Roddy Frame) was part of the Scottish ‘new wave’ of pop artists at that time (see also The Blue Nile, Deacon Blue, etc).

Created in Glasgow, this debut record is still something special, fresh, magical.

Romantic pop it is, but it sounds inspirational, optimistic, full of life and youthful, free-spirited energy. Continue reading

Amplifiers on the bench

After purchasing a (Tonghui) dB-Millivolt meter, I am able to more easily (and more accurately) undertake frequency response measurements of my Preamp and Power amp.

This enables me to directly read relative dB signal voltage output from my amplifier (or preamp) without laborious 20Log Vout/Vin calculations. (Thanks to advice from my pal Clarry.)

I will check out my recently built WOT Preamp and my usual 2A3 Push-pull amplifier. Continue reading

WOT tube Line-stage redux – Pt 1

A Line-stage With Output Transformer (WOT) was built back in 1998, a single 5687 tube per channel with output transformer (OPT).

However I failed to get rid of noise (EM pick-up and attenuator switching noise).  I lacked the expertise to optimise Grounding and to shield and/or orientate the output transformers (OPTs) properly.

Now, I have been fortunate to acquire a pair of Tango NP-126 Line Output transformers. So, I must re-visit the WOT Line-stage. Continue reading