'Decapod' mounting block now fitted:




(With stylus guard.)



(Unique pin config.)

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Look forward to hearing your thoughts with the POD Owen. I prefer the sound with the POD then without.

FYI John doesn't have the rights to the name Decca so he can not use that name with branding, marketing etc.
The cartridges he builds now are branded London.

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Ah yes, I believe that Decca sold the Decca brand name in around '89.

John & Brian (Smith) seem to use the name London Decca for their cartridges

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I've been told a few times by Brian Smith not to use the name Decca in any ads etc when I promote Decca .. ah ... yes, sorry Owen one can use London Decca cartridges :-)
Just not Decca on its own.

Audionut - Artisan Audio At Its Best
www.audionut.net

This is my pick from the London Decca range, the good old Jubilee.
Not much in the way of reviews. Just like the other London Decca's, if you can get it to sing right it will reward you with stunning sound.

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owen - that's a unique pin configuration ?

i seen deccas with 3 pins, 4 in row but never one with the blue pin out by itself.

the john & brian had me confused - those were also the names of the garrott brothers.

"John Wright does not have the rights to the Decca name..."

I had wondered why he called it a Decapod and not a Deccapod as a decapod is a crustacean such as a shrimp or a lobster!  

Owen, did John Wright have to do any extra work on your cartridge to bring it up to scratch? I have a Decca London and he quoted me £150 for examination and fitting a Decapod which seems quite reasonable.

Hi Mark audionut - I had forgotten that you represent London cartridges here.
And interesting thanks, what you say about the Jubilee & Decapod.

mijoh - my Super Gold was only 1 year & a half old...and I'm embarassed to confess that I managed to break it!
Never broken a cartridge before, but I managed to dislodge the stylus holder (I think by bumping the cartridge against the platter) & the stylus was found on the platter (miraculously), with tie-cord & all else intact on the cartridge
(Luckily I got a black platter mat & not a white one )

So, John checked & reinstalled stylus, recalibrated electrical outputs - £130.
Whilst there, I asked him to also supply & fit a Decapod - one less DIY project!

michaelw - if you look carefully at the last pic, you might just see that the blue & green (Ground) pins are tied together with a loop of copper wire at the base of the pins.
(See earlier post, electrical diagram, showing the Decca common Gnd for L & R ch's.)
L & R ch Gnds are 'commoned' or joined inside the preamp anyway (unbalanced circuits), so joining them at the cartridge would seem a smart idea to minimise possible hum (loop) pickup - although you could argue that L & R ch phono ICs (with their separate L & R Gnds), would then form a potential 'hum loop', phono ICs are usually well shielded (except mine!).

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yep, was aware of the internal arrangements, just haven't seen a decca with a 4th leg before

FWIW, a couple of shots of my spare Decca mounting bracket.. as the threads are oh so easily stripped in these mounts...

Never play Leapfrog with a Unicorn.

The Lomdon Decapod is supplied with a couple of tiny M2.5 (or 6BA) hex socket (steel) grubscrews as studs:




But, as I usually have a nerdy obsession with brass cartridge fixings (I prefer the sound of them), I cut down some brass screws & installed them instead.

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The Decca is a difficult cartridge to align, possibly the most difficult I've come across.

This is mainly due to the cantilever-less design & very low clearance from the surface of the record.

Using the parallel-tracking protractor is simple enough in principle.


But actually seeing the diamond stylus, with its +ve raking tip, requires some good lighting.

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Great photos, Owen!
I’ve been using AnalogMagik software to align cartridges recently. It’s quite costly and you need a good analogue to digital converter to analyse the output of your cartridge-phono stage setup. The phono stage needs to be a quiet one as well, and little rumble from your turntable. My 301 unfortunately puts out a bit of low frequency rumble from the idler drive and plays havoc with some of the measurements. Your SP10 should be better!

AMR-iFi R&D

Looking good there Owen.

Yes they do require a bit of patience to set up. An good eye sight 

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My eyesight ain't as good as it once was...but I have a decent cellphone camera now fortunately!

colinf - I have read a bit about the Analog Magik here & there.
I was also interested in the the Fozgometer or using a 'scope for Azimuth setup, but I think I'll stick with mechanical/visual azimuth for now

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A cheap way I found of checking azimuth is with a tape deck having 2 VU meters...

The only other current cartridge that I can think of, that is similar (but different) to the London Decca in this regard is the Tzar DST1.

But this is a Moving Coil, a copy of the historic Neumann DST MC cartridge, with coils attached to the stylus-end of a cantilever (see pic).




The TZAR DST1 is not really cantilever-less & probably has more in common with the currently-available Audio Technica ART-1000 MC cartridge:

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Once upon a time (late 80s) Isamu Ikeda (founder of Fidelity Research) made a cantilever-less MC cartridge, the Ikeda 9C - which Ikeda OEM-manufactured for Jeff Rowland & Cello (Mark Levinson) for a while.

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I guess with these style cartridges because the stylus is difficult to see when lowered onto a record, you’d have to rely on how well the maker aligned the stylus relative to the body, in order to align the cartridge visually by looking at the parallel sides of its casing.

AMR-iFi R&D

give me a naked stylus any day

Where's the fun it that Michaelw  

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Sept 3, 2019 18:43:40 GMT 12 colinf said:

I guess with these style cartridges because the stylus is difficult to see when lowered onto a record, you’d have to rely on how well the maker aligned the stylus relative to the body, in order to align the cartridge visually by looking at the parallel sides of its casing.

Yes, you would expect correct stylus alignment/installation for any cartridge, but at least there are no cantilever misalignment problems - something that I've come across a bit with conventional cantilever cartridges.

As far as stylus type is concerned, you expect a 'naked' diamond (ie, non-bonded) on any quality cartridge.

The aspect that I haven't understood yet, is why the stylus has significant +ve rake - most cartridges have a couple of degrees of negative rake & some, like Ortofon's A90 Replicant, have zero rake (I read, just like the cutting lathe). However, the London Decca seems to work, very well.

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Aug 27, 2019 17:26:39 GMT 12 Owen Y said:

mijoh - my Super Gold was only 1 year & a half old...and I'm embarassed to confess that I managed to break it!
Never broken a cartridge before, but I managed to dislodge the stylus holder (I think by bumping the cartrdige against the platter) & the stylus was found on the platter (miraculously), with tie-cord & all else intact on the cartridge

Sorry to read about that Owen, I know what that experience feels like. I once found the cantilever/stylus from my naked Sumiko Blue Point Special in the sleeve of my jersey! The arm on my Aura TT stood out in space inviting such accidents! I now park it near the centre of the turntable! 

The sound of the Decca London Super Gold, with Decapod mount fitted, seems entirely different from the 'stock' Decca London, with its plastic 2-piece mount.
Not surprising maybe, as the Decapod block is obviously an entirely more solid connection to cartridge & tonearm, than the traditional Decca mount (which can only be described as 'flimsy').

Nevertheless, something visually or mechanically more impressive, does not always mean better sound in this game

The stock Decca London is powerful (bass & 'solid' tonally), energetic, vivid, 'exhilarating'.... it was a touch edgy & 'brittle' at times & lacking some HF sparkle.

The London Decca with Decapod mount, is no less dynamically powerful & 'fast' & solid imaging... but everything else is much better behaved.

Initial impression is disappointment that some 'edge-of'seat' excitement has gone, it sounds more like a 'normal' cartridge, but the extraordinary 'solid', 'human/real' vocal image & tone is still there & everything still has the 'power' & energy & 'presence' (that I've not experienced with in other cartridges). HF tone & extension is much better too.

Another shot of the forward-raking 'line contact' stylus on the Decca London 'Super Gold' (mine) & the unique Decca tie-back cord - taken on a USB microscope :

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Decca cartridges are prone to earthing and hum loop problems, and obviously cannot be used on ferrous platters. I have had ffss cartridges and currently have two Garrot Brothers (RIP)Decca Golds mounted on (separate) Hadcock arms. The Hadcock despite being a unipivot was apparently made for the Decca. The following bit of wiring wisdom is paraphrased from Morgan Jones (2012), "Valves and Amplifiers" (4th Edn), Elsevier Ltd (Pp 589-599). Jones notes that the wiring resistance of the pick up arm can be significant with mc cartridges (not the Decca) and mc transformers such that the DC resistance of the cartridge should be measured (with care) at the preamp input plug to arrive at the correct impedance loading for the cartridge. He also notes that the optimal capacitance loading can be estimated by using a variable two-gang air-spaced tuning capacitor such as found in a typical mw valve radio (e.g. Bell Colt) which are typically 300pf. There is a loop between the balanced cartridge and the balanced input stage of the RIAA circuit (which should have its 0v signal grounded to the chassis) because typical arm wiring and RCA interconnects are not balanced. He therefore advises that the former - at least from the base of the arm if not the tube - be replaced by twisted pairs which are then shielded and the shields bonded to the base of the arm. The next step is to link the base of the arm to the turntable chassis. The turntable motor should be linked to the chassis (star earthing throughout) although most often it is the motor which is earthed first through the mains cord. Connecting the RCA interconnect screens to the respective preamp and turntable earths may create a hum problem. If it does and this is the important bit, remove the link between the arm and the turntable chassis.

I have had no hum problems with this London Decca (even with both Blue & Green cartridge pins connected).

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Jun 21, 2020 22:31:56 GMT 12 Owen Y said:

I have had no hum problems with this London Decca (even with both Blue & Green cartridge pins connected).

Same - no hum ever! Once the Illustrious is back I'll try both of mine! One with Wesley Deccapod, one without and let you know.

I'm loving my current SPU but have been lining up a date with a Decca for aeons. Next up, perhaps.
If I can't afford a new London it may have to be a used Decca.
Good to know there are local users.

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Jun 21, 2020 12:07:05 GMT 12 Owen Y said:

Another shot of the forward-raking 'line contact' stylus on the Decca London 'Super Gold' (mine) & the unique Decca tie-back cord - taken on a USB microscope :

Great pic.

Unusual tie back, strange SRA, coil arrangement. A very interesting cart indeed!

MCs too of course, have a 'tie-back' wire, at the back of the coil assembly.

And when you think about it, the 'conventional' cantilever type cartridge, with stylus SRA of ~2deg 'rearward' rake (except for Ortofon A95 with 0deg SRA), forces the stylus ti 'dig' into the record surface, as it is dragged 'rearward'. ;

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