Duplex

Discussions on Talking Machines of British or European Manufacture
Sherazhyder
Victor I
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Re: Duplex

Post by Sherazhyder »

What I find interesting about this machine is the winding handle suggests it has a repurposed motor possibly form a HMV 102. The tonearm looks like it is from a portable too.
Whilst these fake machines are often referred to as reusing vintage parts, many of the machines currently being made seem to have all new parts, with copies of Garrard or Thorens motors
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Interesting observation

Gramtastic
Victor III
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Re: Duplex

Post by Gramtastic »

It seems there were many experiments with double horn machines. I have a portable with two internal horns and a table model !!

Sherazhyder
Victor I
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Re: Duplex

Post by Sherazhyder »

Gramtastic wrote: Mon Mar 20, 2023 11:37 am It seems there were many experiments with double horn machines. I have a portable with two internal horns and a table model !!
Hi ! Do you have an original machine or a replica? Will you please post some pictures please.
Thank you

Gramtastic
Victor III
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Re: Duplex

Post by Gramtastic »

Hi , Here's the table model. It has the normal horn under the motorboard as usual and a second one in the lid which connects to the bracket holding the tone arm when you shut the lid. Can't find photos of the portable at the moment so will post something later....
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Gramtastic
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Re: Duplex

Post by Gramtastic »

Managed to dig it out of the gramophone room! This is a strange portable by J H Offen who was apparently an employee of Garrard and patented some gramophone inventions. It has two internal horns and a strange corner opening lid ! (I did post some info on it on here many years ago in case it rings a bell with anyone !)
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jamiegramo
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Re: Duplex

Post by jamiegramo »

Thank you Gramtastic for showing these fascinating machines. The original J H Offen pictures are, of course, lost, so it’s good to have a chance to see them.

I used to own a Columbia tabletop with bifurcated horn that sounded very good but I’m not sure any better than without?

With the Kalamazoo Duplex one horn is attached to one side of the soundbox and the other horn to the other side of the soundbox. As I understand it the vibrations from one side of the diaphragm would cancel out those from the other, hence, out of phase. How this sounds in practise I don’t know but it appears that members here do not think it was a particularly good idea.

Edison marketed a similar idea in the 1890s (2 horns but each fed from a different side of the reproducer) called the Edison Duplex. It was shown, however, with the horns pointing in opposite directions. It would be interesting to hear how it sounds with the horns together and then pointing away from each other.

Another machine I can think of was the small Pixie Grippa portable gramophone which utilised each side of the soundbox for sound reproduction.

Sherazhyder
Victor I
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Re: Duplex

Post by Sherazhyder »

Gramtastic wrote: Mon Mar 20, 2023 4:10 pm Hi , Here's the table model. It has the normal horn under the motorboard as usual and a second one in the lid which connects to the bracket holding the tone arm when you shut the lid.
Amazing! Two internal horns connected to a motor. Was this type of machine was ever marketed by any manufacturer?. Whenever I get a commonly available gramophone like HMV 113 , I will modify it to have two horns. Thanks for posting.
Regards
Sheraz

Sherazhyder
Victor I
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Re: Duplex

Post by Sherazhyder »

Gramtastic wrote: Mon Mar 20, 2023 4:30 pm This is a strange portable by J H Offen who was apparently an employee of Garrard and patented some gramophone inventions. It has two internal horns and a strange corner opening lid ! (I did post some info on it on here many years ago in case it rings a bell with anyone !)
Thanks for sharing the pictures. But I could not an idea of the gramophone in its totality. Please share whenever you find it convenient some pictures which give me a complete profile of your machine. Thanks
Sheraz

Sherazhyder
Victor I
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Re: Duplex

Post by Sherazhyder »

Recently, I saw another type of Duplex on gumtree presented for sale. It has two horns fixed on on the back bracket and connected to a single reproducer. The machine box has a decal which is not legible. I don’t know if it’s an original piece or an improvised one. But some of you must have the information.

Best regards
Sheraz
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physicist
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Re: Duplex

Post by physicist »

That would be the Odeon logo.

Another example here:-
viewtopic.php?f=11&t=53917&p=320085&hil ... go#p320085

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