EMG Mark Xb ('Export') serial 657 in Australia - new member

[Jozwolf]

Hi everyone! I have to say I am overwhelmed by this remarkable response to my post and all the generously given information. What a great group of people! Any of you who have gone to my website (http://things-that-count.net (or worse my home page http://metastudies.net) will realise that I am a total amateur on gramophones, but I am a history of calculation technology nut! So I really appreciate coming across the same - actually maybe greater(?) - enthusiasm and expertise that I have enjoyed in the antique calculator world.

Now - Graham (and of course everyone please call me Jim - as an Aussie even the Prime Minister gets called either by his first name or something somewhat more vulgar!) - you have come to a core issue! And I am pretty sure you are right that this is an Xa not an Xb. I only chose the Xb category after some discussion with an expert, but I did not quite give him the information he may have needed. In fact, prior to that I had decided it was an Xa.

My reason for that was that the horn bell circumference at its opening is 90.5 inches (giving a diameter of 28.8 inches, assuming it is circular, - although of course it has become a bit elliptical over the years), Measuring vertically I have a diameter of 28.5 inches, and horizontally 29.1 inches, giving an average diameter of 28.8 inches which matches the measurement induced from the circumference. Further, these are measured to the outer edge of the horn, but I should think the diameter given for the Xa and Xb is to the inner surfaces of the horn(?) and allowing for an approximately 0.15 inch thickness of the papier mache horn wall, this gives us an inner diameter of 28.6 inches.

So the diameter is 28.6 inches which equates well with the listed diameter for the Xa of 28 ⅝ inches = 28.63 inches. What with the information about the thinner knuckle and diameter I think we should conclude this is an EMG Mark Xa ('Export'). Are we agreed?

I attach below a closeup of the deck and another of the outside of the case as requested. For those who are even more curious I have put more pictures up at https://www.dropbox.com/sh/7epl16pngkt5 ... jXqta?dl=0

If indeed this is an Xa it could be suggested this might take us slightly closer to the issue of why its soundbox has a mica diaphragm - from the point of view this is likely to be a bit earlier? Confounding this however is the cabinet with the later features already listed by Graham, and of course the serial number inscribed under the record turntable platen - 657, which seems not particularly early (although also not terribly late!).

Now that I have my strobe disk, once I have dug out a good one, I will set about videoing playing a record and put it up on Youtube for anyone interested.

Once more thanks for all the fascinating information!

Warm good wishes,

Jim

[chunnybh]

This really is a wonderful find. My mistake with saying it's an Xb.
Thanks Graham for the pictures of other Export models. I believe the last picture is of one in Japan.
Here is an awful picture of the one in the Charmsori museum in Korea and of one in this summer's edition of For The Record. John Smith obituary.

[emgcr]

Hello again Jim,

I think we are agreed that you have a Xa ! My own Xa measures 29” vertically and 28 ⅜” horizontally giving an average of 28 11/16” or just over the standard 28 ⅝”. As a point of record, I should say that all the measurements in the abovementioned link were taken externally but would also have to say that, in my opinion, some latitude must be allowed for a hand-constructed item and the passage of time. In passing, it might be of interest to mention that the external diameter of the Xb horn was limited to 29 ½ “ to allow passage through the British standard door opening !

It is also important to remember that the original title of the firm was “EMG handmade gramophones”, thus almost every example was individual and different---in many cases responding to customer specification. The generic imperatives of the various Mk numbers can only be considered a guide as there seems to have been a certain amount of blurring of detail as new developments came along and unsold older parts were used up.

A further difficulty for us when attempting to date a particular gramophone is that alterations have often been made by subsequent owners, either personally or as a result of having returned their examples to the manufacturer for upgrading. The ex-Cobham Hall Xb Oversize (first photo) is a case in point which, having started out as a Xa, was returned to EMG to fit the 33 ½” horn together with longer conduit (second photo). Two number stamps (199 and 333) on the deck-board together with two name-plates perhaps prove the occurrence (photos three and four).

As a rough guide, I have found the following: Mk X had the weakly designed horn (few seem to be known---short casting much like Mk IX) with goose-neck tonearm and short (bronze) conduit. Mk Xa had early cygnet initial aluminium casting with narrow knuckle, swan-neck tonearm and short (aluminium) conduit. Mk Xb and Xb Oversize had later cygnet initial aluminium casting with wide knuckle, swan-neck tonearm and long (aluminium) conduit.

You may like to remove your deck-board to measure your conduit (photos five and six---underside of deck-board to bottom of conduit). This will establish one more piece of the jigsaw.

One further aspect worth observing is the tonearm bearing. It would seem that all EMGs prior to Xa had the bearing formed by loose ball bearings whereas subsequently a fully caged ball race was used. Once again, the time of the Xa production seems to have been one of crossover with earlier examples having loose ball bearings. Further photos (seven and eight) show the different external appearance of both types. The earlier type has a pinch-screw to set ball pressure.

As far as numbers are concerned, the nearest to your # 657 in my records is # 817 and owned by a member of this forum (Orchorsol) which, extremely interestingly, has what we think is a factory hybrid horn with early Xa narrow knuckle but later Xb 29 ½” final diameter. This appears to be a crossover instrument, perhaps using up previous stock. Yet another member of this forum (Frankia) has a Xa # 412 which can be dated to 1932 due to the presence of a bronze name plaque apparently unique to that year according to Frank James. From this, we might infer that your instrument could be 1932/33 but this is still very much conjecture.

The situation is complicated and eternally confusing but also fascinating. I hope this helps a little?

Finally, having thought a little more about your mica diaphragm, it occurs to me that this irregularity may be nothing more than due to the original aluminium equivalent having been accidentally destroyed (easily done when playing a record without effective run-off grooves) and replaced by more easily obtained mica and circular needle holder from an earlier soundbox ? Just a suggestion..............

Good thoughts, Graham.

[Jozwolf]

Thanks again Graham for your obvious expertise and generous advice. Some answers to your questions:

1. The distance from the bottom of the under-board conduit to the under-board is 4.9 inches which I believe makes it the oversize conduit.

2. The tonearm bearing clearly matches your image of the caged ball race, and does not, as a consequence, bear a pinch screw.

I have placed a gallery of images of components at http://metastudies.net/pmwiki/pmwiki.ph ... hisMachine. You can click on any of the thumbnails to see the enlarged image.

I include in the set of images bottom, back and front views of the reproducer. It is possible that you may be able to see whether the needle/diaphragm assembly has been replaced. From an uninformed assessment that seems possible, as you suggest. What do you think?


And now yet another question that I would very much appreciate your advice on.

I see that a number of the horns appear to have had a lacquer applied to the external surface of the papier applique horn, seemingly bringing out the original colour and texture in a very good way. In general I take the position with my calculators that one should interfere as little as possible with their original condition, since the signs of ageing are themselves part of the integrity of the object. But I am of two minds about my EMG Xa horn.

For a start, at one stage in my misguided youth I tried a little furniture polish on the horn. Of course that was a hopeless idea since the wax was instantly absorbed into the material (leaving some light streaks). It may well be possible to remove all traces of that dreadful intervention by dabbing the surface with a cloth wetted with methylated spirits. However, I do not know enough about the material to dare do that without someone more knowledgeable providing advice.

Having done that it would be possible to apply a coat of clear lacquer. There are however so many different approaches to what to use, and indeed it might be a very bad idea for reasons already mentioned, that I would once more treasure the advice of those who have been in this game for a long time.

Do you (or any others in this wonderful forum) have views/advice on this question?

Once more my thanks for generous advice and assistance to date.

Warm good wishes,

Jim

[Orchorsol]

Dear Jim,

A very warm welcome from these quarters too - I have only just caught up with these fascinating developments. What a treasure you have there, and what a wonderful story! And I'm so glad to see how you're most evidently enjoying the unfolding puzzlement, detail and wonder of getting to grips with one of these splendid beasts technically and historically - although, of course, the delivery of the music is the prime enjoyment above all else.

As Graham has suggested, I suspect that mica diaphragm isn't original, or at least not standard... Picking up a good Meltrope would give a better account of the machine's performance in the shorter term, but ultimately, finding another good EMG or Expert soundbox would be the thing to aspire to. You might also want to get a replacement rubber insulator for the back of your soundbox - Chunny can supply them.

I have a similar Collaro D30 motor in my 1928 Mk VIII (lovely and smooth) and as Graham has mentioned, one of my Xbs has the unusual small-knuckle 28 ½" horn which may well be from when production changed over from the Xa - but we will probably never know - as with your diaphragm! - perhaps the original buyer specified mica, being an aficionado of early acoustic records. But the metal diaphragms give such a fine account of acoustics that it's hard to imagine such a thing happening, unless said buyer was highly opinionated! That's another of the astounding properties of EMGs and Experts - the way they get the very best sound quality from virtually all periods of record.

[Jozwolf]

Dear Orchorsol,

Thanks so much for this warm welcome also. Yes - there are multiple viable explanations for the mica. Actually I have already ordered the rubber insulator/gasket for the back of the soundbox from Chunny (and he provided me with very helpful advise before I joined the TMF). (I am well convinced by EMGColonel's test on youtube albeit with the new insulator for a Meltrope!)

But, as you say, what I really need to do now is find myself a good EMG or Expert soundbox with the aluminium diaphragm working well. I am definitely in the market for that so if anyone knows of one that I could purchase I would be extremely interested!

Of course, I do not know whether I dare say this (I am, by nature, very conservative about meddling with antiques), but the alternative would be to have the current soundbox re-fitted with an aluminium diaphragm. I believe Ian Maxted offers that sort of service, but perhaps there are some others who could do it? It depends whether one thinks the current mica diaphragm is original, or a repair using the wrong parts out of then necessity. I would feel easier about repairing a bad prior repair, than mucking around with an original - even if it reflected a poor choice by some purchaser some 83 years ago!

I do agree with you that whilst, it is very interesting to pin down the technicalities and historical placing of this machine after so many years of its comparative anonymity in my possession, the music is the thing! That at least has been available to me, although now I wish to move to some clean records with thorn needles and once the new rubber insulator is in place I expect it will be all the better. Then - one way or another - when I can get hold of a reproducer with an aluminium diaphragm it will be fascinating to listen to the difference.

As a matter of interest - do you have views about my question to Graham about treating the papier appliqué surface of the horn? I notice that some of them appear to have a clear varnish applied - and look all the better for it! As I say, I do harbour an inherent conservatism about meddling - but I am also aware that the horn will deteriorate over time unless provided with some protection.

Once more my thanks,

All the best,

Jim

[Orchorsol]

Apologies, in haste I hadn't noticed that Chunny had already made a similar conjecture to mine regarding the mica diaphragm.

Jim, I've carried out light conservation work on all of my horns, and speaking personally, I'd strongly advocate bare minimum treatment if any. Varnish or lacquer can result in an excessively reflective surface which can be very detrimental to sound. The most I've done on mine is tiny, very light touch-ups with stain or watercolour paint, and/or dilute white glue where the paper layers were flaking slightly, to stabilize the rim. It's all too easy to overdo things and of course any such intervention will be irreversible. Where there are defects, whether wear and tear or from efforts in the past, I think it's usually better to accept them and live with them. Any more, and I think a professional conservator should be involved, but I struggle to think what sort of field would be comparable or relevant to a papier applique horn!

I'm in the process of going much further with a couple of Mk IX horns, but those were pretty much dead losses in the first place condition-wise - very badly sagged, and major surface damage (in one case with much of the original surface removed). These are interesting "explorations" which I'll report back on here at some point in future.

Andy

[Jozwolf]

Thanks Andy. I was editing my earlier comment as you replied - ships passing in the night! But in any case I agree with your caution. I probably feel the same way about meddling with the reproducer. But I am interested in your views on that. Chunny was with me on saying leave it alone and buy another one (Meltrope or better) with an aluminium diaphragm, and obviously if that proves possible I will. There is no urgency, given I have had this thing for 47 years so far!

I have to say it sounds pretty amazing already!

Warm good wishes,

Jim

[chunnybh]

All the "varnished" horns I have seen look awful. This one looks fantastic just as it is. A gentle cleaning is all it really needs. I remember seeing my first EMG and thinking, what an ugly beast. On hearing it, it suddenly became the most beautiful thing I had ever seen. Frank gave me a small sheet of the original paper that EMG used on the horns. It had been kept folded and on opening it I was stunned at the vibrant gold colour of the paper. When new,they must have been quite a sight.
The soundbox on this Xa is confusing and I guess we shall never know if it left the shop like that. To me, the stylus bar looks original.

[emgcr]

Thanks for your quick replies Jim.

I think what this exercise has shown so far is that there are many exceptions that prove the rule ! Having decided that you have a Xa, we now discover that you have the later conduit which perhaps begs the question as to when the longer example was introduced. I had always imagined the changeover came with the Xb which would make sense geometrically/exponentially (longer horn---longer conduit etc) but your discovery tells us that is not so. Your case appears to be of the later variety---also tonearm bearing---so it would seem that this long conduit detail may have appeared towards the end of Xa production---which is new information. Thank you ! Of course, it may well have been that, after tooling up for the Xb, there were still some Xa horns left to be sold which may have appealed to some customers due to price ? We shall probably never know.

On the subject of the soundbox/reproducer, it is not really possible from the photos to see if the stylus platform/needle holder has been replaced---indeed it looks reasonably normal but for the fact that it is not pierced for bamboo etc. The platform is usually supported on two transverse knife edges soldered/screwed to part of the main case although sometimes one support is a pinnacle/conical point which establishes a definite position for the whole assembly in space. The one aspect seen in your photos is that the needle screw is in line with the stylus bar. On most four spring examples I have seen, the screw is slightly offset, I think to facilitate handling (see photos). Your notion of acquiring another soundbox is a good one as many of us have collected various examples over the years which allows comparative listening and the ability to drive oneself (and others) completely insane ! All good fun in the asylum………..

Ian Maxted is probably the best soundbox rebuilder on the planet and I know that Chunny has also had very impressive results. I shall look out for a good four spring example for you but they are scarce birds these days.

Regarding the horn, I very much agree with Andy and Chunny. When I first became interested in EMGs I started out using a MK IX base with an incorrect, very small, paper petal horn. The sound quality, even with such an inappropriate item, was enough to seduce me but I then thought to enhance things cosmetically. Not knowing any better, I painted all surfaces with a gloss paint and totally destroyed the magic of the reproduction !! Even a further coat of matt on the inside did not restore the glorious sound so I would very much counsel you not to play around with any aspect of an original horn. I fully appreciate that it is very tempting to try to enhance the appeal of the paper in some way---especially yours with such obvious, but perhaps slightly subdued, beauty---but I think it would be a big mistake---even on the exterior. There were two reasons for employing paper originally, the first being economic, of course---very cheap and unending supply etc---but the main idea was to use a material which is almost totally inert acoustically so that only the vibrations/frequencies initiated on the record surface are heard without subsequent reflection or alteration anywhere in the sound delivery system. As we know, the whole concept works brilliantly. I would not be concerned about long-term deterioration of the papier-appliqué which is far stronger than it might appear. Obviously it is always very important to avoid damp conditions. The Cobham Hall example, which has had a very hard life indeed and is totally missing much of the material it started out with, is still structurally sound believe it or not !

Having said this, I would have to add that we have made further discoveries when evaluating the new fibre-glass horns (reported elsewhere) which demonstrate the overriding importance of structural stability as well as abraded internal finish---seemingly regardless of material. Interestingly, empirical evidence has also shown that the radii at the end of the bell also contribute to good sound quality---an unexpected component.

Good thoughts, Graham.