Kolster Dynamic Speaker

This speaker is a very interesting example of early electronic audio reproduction. This speaker was built October 12th, 1928. I hope someone who is "in the know" can tell me what model radio it was built for. Audio reproduction in the 1920s was was an ever growing and changing industrial frontier with engineers devising ways to bring more dynamic and high quality audio reproduction for the home consumer. In the latter 1920s about the best quality of audio reproduction one could get in the home was from a Victor Orthophonic acoustic phonograph playing an Orthophonic record that was electrically recorded. Electronic audio reproduction of that era was never as good but the speaker I show in my video is one early example of the strides companies were making to provide better electronic audio.

Category:

Science & Technology

Tags:

• Speaker
• electrodynamic
• Kolster radio
• Brandes Corp
• antique flea market
• Lectophone
• 1920s audio
• early radio

[CLBrinhof]

Cool. I picked up same model (torn cone) in California from a collection that was moving and getting rid of some of their stuff. It came with a tag saying that it is a 1928 Kolster speaker and that the company was originally in Palo Alto, CA. I get the same resistances (35, 7200 ohms) and even without hooking up field coil you get a click if you touch the 35 ohm leads to a 9V battery. Must be residual magnetism from the field coil, even after all those years! Weighs 21 lbs. You want stereo?

[HD7100]

@CLBrinhof Stereo? LOL My Kolster is sitting on the shelf collecting dust. Gary

[pooface006]

nice speaker mate!

[HD7100]

@pooface006 Thanks for looking.

[raymondleeleggs]

I Just bet it still works!

[HD7100]

@raymondleeleggs It might. One coil measures about 35 ohms and the other is over 7k ohms. That confuses me. I will need to depend on someone in the know to tell me how that speaker was used in a circuit. Gary

[HD7100]

@raymondleeleggs The field coil and voice coil are still good so no doubt it will still work. I will eventually try it on something. Thanks for looking. Gary

[batterymaker]

Probably came from one of their large consoles like the Model K-24.

[Murrtalica]

see. i would have liked to live in the time where electricity was getting popular. you could have saw things like this.

[HD7100]

Continued: With the emergence of dynamic style speakers that had permanent magnets the field coil speakers were in turned called "Electro-dynamic". So we actually have two "dynamic" style speakers that have "vibrant" or "lively" moving voice coils. PM which means permanent magnet and electro-dynamic which means speakers with a field coil. Incidently-I worked for the Hammond Organ company back in the late 1960s and was introduced to a wide variety of electro-dynamic speakers.