How do I play MP3s through the tonearm / horn?

[berntd]

Hello

I saw this a few years ago. A friend of mine had a gadget that replaced the Soundbox on the tonearm. One was then able to use a walkman to play music through the machine but without records.
He had 1920s music tapes and it was quite wonderful for entertainment during parties etc. Sounded just like that machine itself was playing.

Nowadays, one should be able to to the same with MP3. and I did a few quick trials with a headphone and a small speaker but none of them seem to transfer enough sound into the tonearm to work properly.

Is there a good way to do this?

Regards
Bernt

[MordEth]

Nowadays, one should be able to to the same with MP3. and I did a few quick trials with a headphone and a small speaker but none of them seem to transfer enough sound into the tonearm to work properly.

Bernt,

I’m not sure if there are any vintage parts for this that you could rewire for a ¼" or ⅛" jack (or perhaps speaker wire)...but I’d think that if you made some sort of gasket to attach a small speaker or pair of headphones, it should work, but the important thing would be getting a good seal (and have headphones or a speaker with good frequency response and drivers).

Has anyone tried to do this? RJsoftware was wanting to do the same thing, although I don’t think I heard if he ever had any success with it or not.

— MordEth

[1926CredenzaOwner]

!

[berntd]

Hello all,

I seem to remember that the gadget my buddy had was made of plastic and it wasn't very big at all. It was almost the size of an earphone piece.

I cannot remember any further details at all eccept that he bought it new in the US during the 1990s.

The pates he played were "Walters 1920s hits" and he bought those as well from somewhere in the US.

Regards
Bernt

[B.B.B]

What would happen if you drop a set of in-ear phones like these in the mouth of the tone-arm, at full volume


& then seal up the mouth with a suitable material.

Maybe too low volume to start with?

Or maby a witch hat horn, turned the other way, so the large part point directly to a speaker,
& the end of the horn is connected to the beginning of the tone-arm?
Hard to get that one air-tight though.

[berntd]

Hello, I tried one of those earphones but I heard nothing from the horn.

I didn't get a good seal though.

I can't imagine the "real" thing to be much more complicated thas a modified earphone.

In addition, I found a patent from the 1960s that describes a gadget for doing what I want BUT it actually vibrates the needle and does not connect in place of the soundbox.
Very cunning and I wonder if such a thing was ever made?


Regards
Bernt

[MordEth]

I think that the seal is the biggest issue, although I don’t think that you’re going to get a lot of volume out of in-ear headphones like B.B.B pictured.

On further thought—my old Sony MDR-V600 studio headphones (pictured below) pump out enough volume to be used as a pair of portable speakers; perhaps you may want to cannibalize one of the earpieces from something like that and seal it to a funnel that can be connected to the tone arm?

You could probably pick up a pair of something similar for rather cheap, used.

Also, you might find this thread to be of some interest.

— MordEth

[Wolfe]

I can't see it working without a proper seal.

But even if you succeed at creating the seal, couldn't some problems arise from the relatively lightweight drivers that most headphones use? It would seem that you would need something pretty stout to create enough force enough to push the air/sound under pressure, through the arm.

A mica/aluminum (or whatever) diphragm via mechanical link would seem better suited to the task than a flimsy plastic driver and tiny electrical signal.

[berntd]

Hello,

yes, that thread is interestin

As an engineering student, I actually had a subject named "audio". Unfortunately it was a long time ago.

I seem to remember that the function of a horn is to match the impedance of the sound source to the impedance of the air.
If this match occurs, then the soundwaves will end up in the air without losses.
This must mean that if the gramophone and horn were properly designed and matched, little sound should be required to produce adequate output.

Does this mean that we have to match the impedance of the speaker / funnel combination to that of the original reproducer for this to work at all?

As I type this, I realise that I don't know enough about it at this stage.


Regards
Bernt

[phonophan79]

I posted this a while ago... while not quite the same as using the orginal machine and horn, it applies the same concept by using those in-ear headphones to amplify sound through a horn.

http://www.hammacher.com/publish/75375.asp#