LOUNGE Audio LCR Gold phono preamp – Pt 3 New PSU

In 2019, my LOUNGE LCR phono preamp was upgraded to a LCR Gold phono (plus a few extras), by LOUNGE AUDIO (Robert Morin) in California.

Everything now well ‘run-in’ and some initial ‘brightness’ has disappeared (exactly as Robert had advised).

How good is this phono stage? This is not a device that impresses in an ‘artificial’ way. Let me just say that, (sadly) I have no urge to return to my Diego Nardi Phi-42 all-tube phono preamp.

Now, I really wanted to improve the external AC Power Supply to this phono stage.

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Magic and Microphony (Pt 2) – 6SN7GT tubes

Back in 2015 – Magic and Microphony (Pt 1) – I suggested that the tendency to ‘microphony’ in some vacuum tubes / valves, can actually enhance the sense of ‘ambience’ or ‘live-ness’ of the reproduced sound.

The last thing I wish for, is a ‘dry’ or ‘threadbare’ sound that is lacking in ‘resonance’ or harmonic ‘decay’.

However, having moved on from a 2-stage tube preamp, back to a single-tube, ‘WOT’ (With Output Transformer) Tube Line-stage, I’ve found that sensitivity to ‘microphony’ can be a serious problem.

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TECHNICS SP-10MkII turntable – Pt 5 plinth support

Previously, I used 4 x ‘mag-lev’ (magnetic levitation) support ‘feet’ under the new plinth on my TECHNICS SP-10MkII – similar to the mag-lev feet used under my previous turntable.

However, I found that this turntable sounds much better supported on top of (3) solid plywood blocks.

Supporting the plywood plinth perimeter – the sound is sharper, clearer, dynamic, rhythmic, with a light, ‘agile’ touch. Image height and scale are good. There is nice treble extension, nice tonal ‘sustain’.

This is an example of why you cannot just assume that what works on one turntable (eg. rim-drive) will work similarly on another turntable (direct-drive).

Always use and trust your ears! 

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Fidelity Research FRT-4 MC cartridge transformer

This has ended up being my favourite cartridge step-up transformer (SUT) whenever I am using a Moving Coil cartridge.

The Fidelity Research FRT-4 SUT is versatile, with 4 x Gain/Impedance ratios and it sounds very good.

It is better sounding than my Fidelity Research FRT-3 (dynamic but slightly ‘coarse’ in comparison) or the very good Stevens & Billington TX103 (less extended treble tone).

Fidelity Research operated from Tokyo from 1964 – 1984.

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GAINCLONE Amplifier build

It all started in 1999.

47 Laboratory (Junji Kimura) introduced the 4706 Gaincard amplifier, which produced 25 Watts per channel from a single IC chip amplifier per channel.

The special features of this amplifier design were:

  • A ‘high-end’ dual-mono amplifier designed around a single power IC (per channel)
  • The world’s smallest number of parts in an amplifier (9 per channel)
  • The world’s shortest signal path length (32mm including parts lengths)
  • The world’s shortest negative feedback loop (9mm)
  • Smallest possible Power Supply filter capacitance (1,000uF) combined with a high capacity power transformer
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KEITH MONKS Record Cleaning Machine

The Keith Monks Record Cleaning Machine was introduced in 1969 and is still unique in the method used to vacuum-dry the cleaning fluid from the vinyl record.

The KMAL (Keith Monks Audio Ltd) Record Cleaning Machine was originally developed from a ‘Record Doctor’ concept devised by Percy Wilson in England and presented to the Audio Engineering Society (AES) in 1965.

In 1969, Keith Monks was successful in securing orders from the BBC for the first KMAL Record Cleaning Machines to be manufactured.

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Vacuum tube Headphone Amp-DAC

The Sennheiser HD 650 is a great headphone with a little bit of sonic ‘magic’ appeal. The attractively priced MassDrop HD 6XX version is a special bargain.

A popular and nice match for the Sennheiser HD 650 / HD 6XX is a vacuum tube headphone amplifier.

The project here was built by Jeremy Young. It was inspired by the Bottlehead OTL headphone amp, but circuit ‘operating points’ were determined to suit a locally made power transformer.

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LONDON DECCA cartridge – Pt 2 with Decapod

Replacing the standard Decca 2-piece plastic mount with a ‘Decapod’ (solid aluminium) mount, is essential in my opinion and I recommend it.

The Decapod ‘mounting block’ is obviously a much more solid connection between the cartridge and the tonearm, than the original Decca design

And, I can advise that the Decapod will transform the sound of your ‘standard’ London Decca or Decca cartridge.

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Fidelity Research FR-64 tonearm

This vintage Japanese tonearm still enjoys a certain ‘cult’ status.

Fidelity Research Co. was founded by Isamu Ikeda in 1964 and the FR-64 tonearm was introduced in 1978. Fidelity Research closed down c.1984.

(A new company, Ikeda Sound Labs, currently again offers new cartridge & tonearm products.)

The detailing and machine-finishing is visually uncomplicated. After 40 years, it still looks elegant and the material is durable and un-tarnished.

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