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View Full Version : "Something old, something new, something borrowed, something Blue"



Barry
07-01-2011, 23:52
Recently I have had the pleasure of listening to two cartridges that despite having ‘Blue’ in their title, could not be more different: a Decca Mk. V fitted with a spherical tip (also known as the Decca blue) and a Sumiko ‘Blue Point Special’ fitted with an elliptical tip.


Something old and something Blue
Having recently written enthusiastically and in depth of the Decca Mk VI (a.k.a the Decca ‘Gold’) http://theartofsound.net/forum/showthread.php?t=7107, and having loaned the cartridge to a fellow member, I wanted to see if the Decca ‘magic’ could be supplied by the humbler version fitted with a 15μm spherical tip: the Decca ‘Blue’. My sample is at least 25 years old and was bought with the intention of sending it off to Australia to the (late) Garrott brothers for them to fit a Weinz parabolic stylus and generally give the cartridge their ‘make-over’ (the standard of workmanship of Decca’s at that time was, quite frankly, appalling). In the end I had such work done on another sample: unfortunately I can’t find it (!)

Suspecting that in the absence of the GB mounting block referred to the above cited post and owing to their low compliance, Deccas might benefit from additional mass, either through using a heavy headshell or a headshell weight, I somewhat perversely chose to mount the cartridge in an empty EMT headshell (EMT TSD-G) and use this with an EMT/SME bayonet adapter. There are two reasons why I did this: firstly, I had seen a photograph of such an assembly and was curious to try it for myself, secondly the available space in the EMT headshell is quite small and there are few cartridges that will fit. I bought the headshell intending to fit the Denon DL103 cartridge into it, so as to compare the Denon with the EMT TSD-15, however I found the body of the Denon was just too long, causing the output pins of the latter to clash with those of the headshell (I have seen a photograph of a 103 fitted into a TSD-G shell, however I suspect the pins of the cartridge had been trimmed, and even then the clearance was miniscule and the contact lugs and leads had to be very carefully dressed). The Decca was fitted to the headshell using Decca’s own plastic mounting hardware as shown in the following photograph.

http://i780.photobucket.com/albums/yy88/barrydhunt/224.jpg?t=1294440966

Decca’s use a three-wire system. Depending on one’s system it may be sufficient to ignore one or other of the return connections (the blue and green coloured leads), for my system it is essential that both return leads are connected to the common terminal, and to do this both were soldered to the contact lug.

The cartridge/headshell/adapter assembly was fitted to an SME 3009/II arm and was easily balanced using a double set of tracking force weights. Tracking was set at 3g with 1.5g of bias correction. The arm was fitted with the FD200 damping dashpot with which the black damping paddle was used, providing the lightest damping. VTA was set ensuring the arm was exactly parallel with the record surface. Overhang was set using the sliding bedplate of the arm, using a two-point alignment protractor. Azimuth was also set at the arm, rather than at the headshell, using a mirror.

With compliance figures of 12cu lateral and 5cu vertical and with an overall cartridge/headshell/adapter mass of 22.6g, the LF resonances are calculated to be 8.5Hz lateral, 13.2Hz vertical; not ideal but I encountered no problems (possibly helped by the damping used).

The Decca ‘Blue’ has an output of 7.5mV at 5cm/sec with a recommended loading of 50KΩ. I ran it into the moving magnet input of a Quad 44 preamp providing 47KΩ with the option of switching in 180pF of capacitance. I used the latter loading but the effect is very small: quite different to my experience with the Decca Gold. I shall revisit the Gold to try to understand why I found it necessary to use an enormous amount of capacitive loading, however then I was using a Quad 33 preamp, this time I used a Quad 44 for the RIAA equalisation stage, which in turn feeds a Levinson ML28 preamp.

http://i780.photobucket.com/albums/yy88/barrydhunt/215.jpg?t=1294431881

I must at this point mention that the integrity of the cartridge-arm connections is vital and of paramount importance. Initially I was plagued with all sorts of random and alarming clicks, pops and bangs (possibly due to static discharge), hum when the arm was handled and the whole arm/cartridge seemed especially microphonic, producing uncomfortable handling noises. Furthermore, at times, the midrange could appear recessed, distant and ‘hollow’. I traced the problem to an imperfect mating of the EMT headshell to the EMT/SME adapter; the bayonet fixing here has to be tightly made. Once corrected the set-up proved to be well behaved and an absolute delight to use.

So to the musical performance – once again that indefinable Decca ‘magic’ was there, not to the same extent as that displayed by the Gold, but was there nonetheless. Treble was very well behaved with no ‘nasties’ and when I did hear the occasional tracing distortion that was due to the record being in less than perfect condition. Transient attack was as good as ever, if not quite so ‘jaw dropping’ as the Gold. Bass performance was however on a par with the Gold. The sense of presence was there too, though again not to the same extent as that provided by the Gold. Soundstage was wide and deep, possibly deeper than that displayed by the Gold and stable. The tracking of the Blue particularly impressed me, especially as Deccas are not known for their tracking abilities, and one would expect a spherical tipped stylus not to have as good a tracking ability as one with an elliptical tip. There was no ‘end of side’ distortion. As mentioned with the Decca Gold, owing to the very small clearance between the underside of the cartridge and the record surface, all Deccas need to have their styli cleaned regularly.

Once again there was the ‘fun’ or ‘hugely enjoyable’ effect at work – I just wanted to play LP after LP. Deccas seem to ably portray a sense of timing and rhythm to what ever is being played that, when appropriate, has you tapping your toe and generally just moving to the music. It involves you. I don’t believe the Deccas to be the most tonally accurate of cartridges, but they have that certain something, a life or a presence, that I like to call the ‘Decca magic’.

The next step will be to replace the Blue with the Gold, retaining the same set up (apart from tracking force) to compare the two. One thing is for sure, I’m always going to have a Decca set up and available from now on, even though I believe my moving coil cartridges to be more ‘accurate’.


Something new, something borrowed and something Blue
This is the Sumiko ‘Blue Point Special’: ‘new’ to me and ‘borrowed’ as it was on loan for a short period (about three weeks) for audition. It is not the Evo III version, but its predecessor.

http://www.audiovenue.co.uk/itemimages/bluepointspecial(1).jpg
Photo: Audiovenue

It is a high output (2.5mV) moving coil cartridge of moderate compliance (12cu), fitted with a 7.5 x 18μm tip. It is designed to operate into a conventional moving magnet input of 47KΩ.

It came already fitted into an SME S2-R headshell (mass 8g) and was set up in an SME 3009/II arm and tracked at 2g. Bias compensation was set to half this amount. Again very light damping was used. Calculated LF resonance in this set-up is an ideal 9.5Hz.

http://i780.photobucket.com/albums/yy88/barrydhunt/004-1.jpg?t=1294441436

Being on loan, I was reluctant to fuss with this arrangement; especially, as can be seen, the generator is naked with a cantilever 4mm long that is almost asking to be snapped! I should add that the cartridge comes with no stylus protection whatsoever. Quite frankly I regard this as the height of arrogance by the manufacture to fail to provide even the most palliative measures to protect such a vulnerable cantilever. How do they suppose you fit this cartridge to a fixed headshell arm, with the arm in situ?

http://i780.photobucket.com/albums/yy88/barrydhunt/006-2.jpg?t=1294441656

On a technical level this cartridge is hard to fault, especially at the price (~ £250). It offers a wide seamless bandwidth with a smooth unforced treble. Bass is solid and taut, if not especially deep (but then the speakers I use are not particularly revealing in this aspect). Midrange is detailed and the sense of dynamics adequately well portrayed. The soundstage is acceptably wide and deep, though I have heard better with some other cartridges.

Tracking capability of this cartridge is good: it was never caught out. Being a loan item, I was reluctant to experiment with the tracking force. The 2g used was recommended by the owner, who incidentally commented that the cartridge sounded better in my system than in his.

Given the reasonable cost of this cartridge the technical performance is nigh on perfect and I could recommend it wholeheartedly were it not for a fatal flaw: the cartridge simply did not engage me. There were several occasions when I found myself just not paying attention to what was being played – quite the opposite to the Decca. Neither did I want to follow LP after LP after LP, again the opposite to the environment created by the Decca.

So here we have a bit of a dilemma, on the one hand we have a cartridge, the Decca, that is not the most accurate of transducers, yet has the ability to get to the heart and soul of what is being played and on the other hand the Sumiko, which whilst technically better, seems to rob LPs of their life and enjoyment. Perhaps if I had had more time to experiment with VTF and VTA I might have improved matters. However the cartridge was not mine and with its vulnerable cantilever just using it, and keeping it clean almost gave me the heebie-jeebies!

I won’t be buying one, and would prefer to put the cost towards an Ortofon SPU. I really must try and find that Garrott Decca!

Alex_UK
08-01-2011, 00:12
Superb write up as usual Barry, thank you for taking the time.

The Grand Wazoo
08-01-2011, 00:19
Yes Barry, very interesting thanks.
I've been promising myself a chance at having a go on a Decca for years. This make me want to bring that day closer!

Marco
11-01-2011, 19:09
A most interesting and superbly written piece as usual, Barry :)

I feel that a special reward is in order for managing to fit a Decca into an EMT headshell, and reasonably elegantly too! :respect:

It would be interesting to compare the Decca Blue to the Gold, so I look forward to being able to do that sometime. I loved the Gold very much, but there's a magic about conical styli which I can't quite put my finger on, even if they're not as accurate...

There are a few other points you've raised I'd like to touch on, so I'll comment more on your excellent article later :cool:

Marco.

John
11-01-2011, 19:15
Great write up Barry

Barry
13-01-2011, 18:59
A most interesting and superbly written piece as usual, Barry :)

I feel that a special reward is in order for managing to fit a Decca into an EMT headshell, and reasonably elegantly too! :respect:
It would be interesting to compare the Decca Blue to the Gold, so I look forward to being able to do that sometime. I loved the Gold very much, but there's a magic about conical styli which I can't quite put my finger on, even if they're not as accurate...

There are a few other points you've raised I'd like to touch on, so I'll comment more on your excellent article later :cool:

Marco.

Thanks Marco,

Personally I think it looks a bit of a 'dogs dinner' - but it works. :eyebrows: The leads of the EMT shell are very thin and flimsy: a cartridge tag had broken off and whilst trying to strip a little of the insulation in order to re-solder the tag, the wire broke away from the contact pip of the bayonet stub! Some very delicate soldering was necessary.

In many ways the design of the EMT shell is poor: the cartidge wires are soldered to the very tips of the bayonet contacts, and are quite delicate and frail.

Anyway now it all works, though I would like to replace the 'average' quality cartridge clips with some nice gold plated items.

I feel bad about dismissing the Sumiko design. With more time to experiment with VTA and VTF, I might have got more out of it. I would have liked to have been able to mount the BPS in a Breuer pick up, but as commented, with such a long, exposed and vulnerable cantilever, that is not for the faint hearted (and for this cartridge, I include myself in that catagory)!