The Talking Machine Forum — For All Antique Phonographs & Recordings

Hello all:
I have a 1927 VV4-3 Consolette machine from the original owner that has what must have been a replacement ortho reproducer. I know it must be from 1929 onwards, but wonder when they went to a round-hole needle bar rather than triangular. Also, was the diaphragm screen standard by then, and not just for portables? Thanks for any history on this!
Bob

I'm not sure when they dumped the triangular hole in them, but all of the later RCA Victor ones like this I've seen have the round hole and the screen. I really like this style reproducer, they sound great and they're easily taken apart, the pot metal is very good quality. My 8-35 came with two of them, one still in the box obviously never used. My 10-50 also came with one of these. I always wondered if this meant that the pot metal on some of the earlier Ortho reproducers was unstable and fell apart even then?

I know this doesn't really answer any of your questions, Bob, but rather it adds a little more meat to the sauce, as it were!

Sean

Thanks Sean-
I agree this type looks and sounds just fine.
Bob

That is a nice looking reproducer. Do the words quality and potmetal ever really belong next to each other? Perhaps it not potmetal but some other mixture of elements?

Couch Potato wrote:That is a nice looking reproducer. Do the words quality and potmetal ever really belong next to each other? Perhaps it not potmetal but some other mixture of elements?

Pot metal is not a formula, it's a generic term. The most common name was Spelter, usually applied to a zinc composition used for casting sculpture. It made fine detailed castings but had severe decomp issues.

estott wrote:

Couch Potato wrote:That is a nice looking reproducer. Do the words quality and potmetal ever really belong next to each other? Perhaps it not potmetal but some other mixture of elements?

Pot metal is not a formula, it's a generic term. The most common name was Spelter, usually applied to a zinc composition used for casting sculpture. It made fine detailed castings but had severe decomp issues.

The time of day when the item was cast had a great effect on its later stability. I remember being told at a car club meet that the mixture started out pure at the beginning of the shift, and guys would throw their old cigarette packs in it (made of lead back then) so by the end of the day there was a lot of crap in the metal.

My 2-65 came with one of these, but in a gold color. Is there a "spider" on yours? Mine has no spider - the feet were snipped off close to the diaphragm, and a long double-pronged connector used betweeen diaphragm & stylus bar. RCA must have been using up old parts, instead of having new diaphragms made!

Edisone wrote:My 2-65 came with one of these, but in a gold color. Is there a "spider" on yours? Mine has no spider - the feet were snipped off close to the diaphragm, and a long double-pronged connector used betweeen diaphragm & stylus bar. RCA must have been using up old parts, instead of having new diaphragms made!

The late ones omitted the spider. Less chance of damage, I can't hear the difference.

Edisone wrote:My 2-65 came with one of these, but in a gold color. Is there a "spider" on yours? Mine has no spider - the feet were snipped off close to the diaphragm, and a long double-pronged connector used between diaphragm & stylus bar. RCA must have been using up old parts, instead of having new diaphragms made!

You are correct, they did cut the "legs" off of the spiders on the later ones. I'm sure there was a reason for this, however, I found the earlier ones with the spider to be fuller in sound and have better bass response than their amputated successors. The difference was really only noticeable in larger machines like a credenza or 8-35.

Time of day did have a great influence on the long-term durability of the die castings. (these are all technically die castings, whether we call them otherwise or not). However, while it's possible that operators would drop cigaret butts into the mixture --although that seems a bit doubtful since the die-casting machines were/are one-man operations, with the mold numbers keyed to his machine, and it would seem that the superintendant would have someting to say about this practice-- a more important variable is mold temperature. Too cold or too hot, and the structure of the internal casting changes. Early in the day or just after lunch = too cold. Well into a long production run = too hot.

This problem was discovered in the early 1930s and corrected for the most part, making die castings from then on fairly consistent and durable over time.

Of course alloy content also effects long-term durability. Cheaper manufacturers used (and still use) cheaper alloys. (Think of Taiwan "tools" from Harbor Freight and similar travesties today that break in hand.)

A friend in Australia has studied surviving die castings of the teens and twenties. There is a great variation in the microstructure from part to part, with certain microstructures surviving till today with great success. The poor ones have an open sturcture --something like porosity-- that allows impurities to migrate into the metal stucture, binding with certain elements, turning them brittle and causing them to expand and crack. These poor ones almost become like ceramics, subject to breaking when dropped or mishandled.