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The bonding of the needle bar to the diaphragm can sometimes give trouble. If it looks a little suspect I sometimes wick a small amount of cyanoacrylate glue behind the cup, or wax with heat.

gramophone-georg wrote:

Orchorsol wrote: Hmmm, that seems to be basically what I used. Scratching my head on this one. I can appreciate what an earlier poster said about the difference the machine itself makes, but I'd expect this Mel to perform at least on par with the existing soundboxes on the machines I'm using to test it.

The Meltrope should produce a better sound on the 104 than the HMV 4, but on my 130 (acoustically identical to the 104) the Meltrope does not result in any improvement over the HMV 5B.

Have you noticed that the there are two little rubber pads on the opposite side of the bearing, in between the needle bar and the external round cover? if the rubber is hard the soundbox will sound poorly. Another area to check is the attachment of the needlebar to the diaphragm, it is soldered but it can come loose or semi-detached. A third point to check is the symmetry of the attachment points of the external cover towards the bearing. This soundbox does not have springs, it relies on the pressure of the cover to pre-load the bearings, and if one side is nearer the needle bar than the other, it will result also in poor sound - I have one with such problem, one side was slightly warped, and I could not fix it satisfactorily.

CarlosV wrote:

gramophone-georg wrote:

Orchorsol wrote: Hmmm, that seems to be basically what I used. Scratching my head on this one. I can appreciate what an earlier poster said about the difference the machine itself makes, but I'd expect this Mel to perform at least on par with the existing soundboxes on the machines I'm using to test it.

The Meltrope should produce a better sound on the 104 than the HMV 4, but on my 130 (acoustically identical to the 104) the Meltrope does not result in any improvement over the HMV 5B.

Have you noticed that the there are two little rubber pads on the opposite side of the bearing, in between the needle bar and the external round cover? if the rubber is hard the soundbox will sound poorly. Another area to check is the attachment of the needlebar to the diaphragm, it is soldered but it can come loose or semi-detached. A third point to check is the symmetry of the attachment points of the external cover towards the bearing. This soundbox does not have springs, it relies on the pressure of the cover to pre-load the bearings, and if one side is nearer the needle bar than the other, it will result also in poor sound - I have one with such problem, one side was slightly warped, and I could not fix it satisfactorily.

Maybe we're getting somewhere- no rubber pads in sight on this one.

But again... wouldn't that cause the box to rattle? This one doesn't.

No rubber pads on mine either, nor have I ever seen rubber pads on these. I'm afraid I'm not a fan of Meltrope soundboxes. The only adjustment that can be made is to the screws that hold the front cover on. Too tight, and the needle bar movement is restricted, too loose and everything rattles. When the balance is exactly right, within a few weeks of use, the screws work loose, and it all has to be done again. And as for the way the needle bar is riveted to the diaphragm......

Phono48 wrote:No rubber pads on mine either, nor have I ever seen rubber pads on these. I'm afraid I'm not a fan of Meltrope soundboxes. The only adjustment that can be made is to the screws that hold the front cover on. Too tight, and the needle bar movement is restricted, too loose and everything rattles. When the balance is exactly right, within a few weeks of use, the screws work loose, and it all has to be done again. And as for the way the needle bar is riveted to the diaphragm......

These shortcomings are exactly what I experienced with them. As to the rubber pads, here is a photo:

Ouch! Those rubber pads are definitely not original, and make the front cover stand away from the body at an alarming angle. Had they been much smaller than they are, the basic idea would have been a good one, although the needle bar would have had difficulty in trying to swing on solid rubber, rather than the two tiny ball bearings that are supposed to be there.

larryh wrote:In a recent thread about needles and the importance they play in determining the sound, some of the European members chimed in on the fact that usually a well built and maintained reproducer from the orthophonic era on could, or should, play as well as any so long as properly maintained. That made me wonder if there are any particular secrets to producing the optimum sound from these late reproducers? I have been told that a good one working well shouldn't exhibit a metallic sound on loud portions, something I too dislike. But where does that effect come from or what might cure it? I know these are very subjective questions but I thought maybe some of our European friends may have some insight on how to bring these back to near original sound. Are there any particular "experts" that seem able to revive these or improve on them when needed?

Dear Larry, unfortunately your nice post has been hijacked by the "same'ol" Meltrope fans, who perhaps should have opened a thread of their own. I hope this didn't give you a bad image of the European subscribers of this forum, since you asked for their opinions specifically. Meltropes are one of the many third-party soundboxes available at the time, but for some reason they rose to cult status in UK lately. Contrariwise to what written earlier, they are so rare and difficult to find (a search on eBay this morning returns ZERO results worldwide) that, personally, I wonder about the utility to mention them here.

Back to topic, there are no real "secrets" about reahauling orthophonic soundboxes. Concerning metallic sound specifically, in Columbia Viva-Tonal soundboxes this may be due to a cracked aluminium diaphragm (no serious possibility to repair it in this case: it has to be replaced with a generic spare part cut to size), to a loosen screw at the needlebar-diaphragm join (this must be tightened and sealed with wax, without using force as the aluminium diaphragm is very delicate and easy to rip or bend) or by dried-up rubber gaskets. At least in my experience, red Columbia rubber gaskets were made in a much more lasting material than HMV's white tubing, and are usually found still quite soft, but "the safe way" is to replace them anyway. The same applies to HMV orthophonics, except thatthey don't have rubber gaskets but felt pads, which basically last forever unless eaten by insects or alike, so they can be considered "maintenance free" from this perspective.

Another major cause of metallic sound are the joins of the stylus bar. Both Columbia and Victor styli pivot on ball bearings. The stylus bar has to be completely de-assembled, the balls of the bearing (and of course their receptacle) cleaned one by one with gasoline, re-lubricated, re-installed and adjusted so that there is just enough backlash for the needle bar to swing. This is done by ear, while playing a test record; my experience on the field tells me that the ball bearings have to be tightened sligthly more than you would think at first. It is also important that the needlebar is adjusted in such a way that, when everything is screwed back in position, the bar end barely touches the diaphragm dome/spider. The diaphragm must not be pulled or pushed constantly on either side by a misaligned bar: this will cause a severe distortion. When at rest, the diaphragm must rest freely in its neutral position.

Usually, the isolator is mentoned at this point. However, the isolator has little or nothing to do with metallic sound unless it is so hardened and/or deformed that the soundbox phisically rattles over the tonearm (or makes the tonearm itself rattle), which is a very rare condition. An isolator which is simply no longer airtight will primarily dampen the lower end of the frequency spectrum due to pressure loss, but would not cause a metallic sound. If a decent spare part is available (it is not so for all types of isolators) it is a good practice to replace the isolator in any case, although the improvement in sound is barely audible in most cases.

Marco Gilardetti wrote: Back to topic, there are no real "secrets" about reahauling orthophonic soundboxes.

Thanks for putting the conversation back on track, Marco. Your comments are all pertinent, as usual, with one clarification: the specific orthophonic soundboxes (I refer to the Victor trade name) are very difficult to service, they require special tools to remove the needle bar and to remove and reinstall the bearings.

Correct, and at least some of them have parts made with pot metal which became very delicate with time; these should be serviced with extreme care, or better not serviced at all. However, not having rubber gaskets, maintenance can be kept to a minimum in many cases. In few words: I would suggest to buy an orthophonic soundbox only by a reputable collector who assures that the soundbox is flawless and sounds good.

CarlosV wrote:

Marco Gilardetti wrote: Back to topic, there are no real "secrets" about reahauling orthophonic soundboxes.

Thanks for putting the conversation back on track, Marco. Your comments are all pertinent, as usual, with one clarification: the specific orthophonic soundboxes (I refer to the Victor trade name) are very difficult to service, they require special tools to remove the needle bar and to remove and reinstall the bearings.

I respectfully and vehemently disagree that this was off topic at all.

1. A Meltrope is a reproducer.
2. Where else to ask about it but in the British and European forum?
3. The questions and were directly related to making a good reproducer work well.

Now, as far as Orthophonics go... I'd like to add two things to the conversation:

1. In my personal experience I've gotten very good results with adding a light grease to the needlebar bearings, tightening them tight to seat them, then backing off until you achieve ultimate sound quality.

2. I'm going to argue that the isolator condition and proper suppleness is absolutely critical. Not only does it need to seal the reproducer to the arm, a good supple isolator allows it to reproduce high notes with far better efficiency, and, even more important, cuts down needle and record wear, as well as significantly reducing surface noise.

As far as bringing back the suppleness to a stiff isolator, I've had occasional moderate success in giving them a three to five minute lacquer thinner "bath", drying them off, then coating with a petroleum jelly like Vaseline and letting that absorb for several days, adding Vaseline as necessary when the isolator starts looking "dry". A mineral oil soak can be helpful as well. If you have some hard isolators, experiment. I most certainly haven't done this on every type of isolator, and sometimes they're just too crystalised to have any effect, and if the isolator is already crumbling, it's toast. Plus, there may well be some isolators made of materials that these chemicals will attack, so keep your junkers, play, and take notes.

I agree that the Victor isolators reproduced today are slightly too hard. An interesting eye opener about that was when I had Mica Monster do a couple orthophonics for me last year to see what all the fuss was about. The guy injects clear silicone into the back of the reproducer as an isolator using the original inner ring... and what a difference in fidelity (although volume drops, but only slightly). I can play the same disc with an HMV or Victor orthophonic with the regular black isolator (or multiple ones), then install Wyatt's with the injected silicone isolator, and with Wyatt's reproducer I hear the other half of the music that was missing... the traps, cymbals, high muted trumpet in the background...

This only makes sense as a reproducer is a device to transfer vibration... and if it's stiff anywhere, it can only vibrate so fast! A stiff isolator will tend to transfer certain vibrations to the tone arm rather than the air. It'll also really bring out surface noise. If you've ever had a badly maladjusted reproducer you'll know just what I'm talking about, too, because a too tight needlebar exhibits a lot of the same sins.

Victor discovered this themselves, actually. If you've ever owned an Improved Concert reproducer for a tapering arm, you'll see what I mean. Play the Concert first (non- isolator), then a Victrola #2 (with a good isolator). The isolator is key, especially with electric records!

This swings us back around to my poor Meltrope. The thing I noticed about Wyatt's injected silicone isolators was the perceptible "give" they have when installed on a tone arm. The Meltrope I have exhibits some of that, too, as its isolator is nice and supple, so I was sort of surprised (not in a good way) by the aural results seeing as how these are supposedly such great reproducers.