Schuchhardt microphone

[unrealdave]

Hi all

I got this the other day – it’s a 1928 German microphone.  It reads just under 60 Ohms.

There is a bit of info on this site https://www.radiomuseum.org/r/schuchhard...ophon.html

But I can’t find anything else.  Does anyone have any info on it?  Its made just as the bad guys started taking over so I wonder what rubbish has gone through this......

[beamcurrent]

Hello Dave

I have no real information, but my curiosity was aroused by what appears to be 6 microphone inserts?

I wondered how they were arranged electrically. what came to mind was the possibility that they were in say parallel to provide more power output? maybe as a transmitter modulator?

Brian

[unrealdave]

Unfortunately I cant get the back off without damaging the thing , but yes there are 6 inserts

[Hartley118]

I wonder whether they're carbon granule inserts. Can you hear the granules rattling when you shake it?

Martin

[unrealdave]

No - no rattling. Also the Ohm reading stays the same when I move it about so I think its a moving coil microphone with 6 coils. Capt. Round developed the first moving coil mike in 1923 so it would be an improvement on his design I guess as its from 1928 / 29

[Terry]

Dave, could this arrangement have been an attempt, successful or otherwise, to create a highly directional microphone?

I'm thinking here of the way line source speaker - aka column speakers - focus the sound coverage in the vertical plane whilst giving a wide dispersal action in the horizontal plane (with the column mounted vertically as usually found).

I recall a very interesting use of such speakers that I encountered in the 60s at the BBC studio at the (former) Paris theatre.

The auditorium was, from memory, roughly square and the PA used four line source speakers mounted horizontally, two on each side, at the top of the wall just below the (lowish) ceiling and angled downwards towards the bottom corner on the opposite side.

The coverage was excellent and the shape of the beam prevented both overspill onto the stage and reflections from the back wall which, in  a radio studio was, of course, the highly reflective large glass window at the front of the control room..

I also noted an ingenious use for a 5th column - it was suspended centrally over the stage running from front to back and used for talk back. Thus the sound was dispersed from left to right and reasonably constrained to the performing area.

How about a pair of line source speaker using a mere one hundred drivers?

[unrealdave]

Not sure about that Terry...

Its a shame I cant get it open but even taking the felt off the back I might not get it apart.

Anyway some more info - its .37 kilo in weight and 11 cm diameter

[Terry]

I wondered how they were arranged electrically. what came to mind was the possibility that they were in say parallel to provide more power output? maybe as a transmitter modulator?

It wouldn't matter how they were connected, Brian, assuming that there isn't anything connected in antiphase for some strange reason.

Series, parallel or series parallel, the output power would be the same although, obviously, the impedance would vary, dependent on the individual arrangement.

Its a shame I cant get it open but even taking the felt off the back I might not get it apart.

If it works, there is nothing to be gained by taking it apart but everything to lose if you damage it, so I'd leave well alone, Dave.

[Crackle]

How about a pair of line source speaker using a mere one hundred drivers?

Its a pity he did not mount the bass speakers behind the baffle in the same way as the tweeters and routed the bass openings as well, it would have looked so much nicer.

Terry, we used column speakers at the "old" Towngate Theatre and they do "throw" the sound right back to the rear of the auditorium but they were "100v line speakers" because of the type of high impedance low loss output they were designed to be used with. Why are the speakers you refer to called "line speakers". I have not come across that term before, I suspect they are not 100 volt line fed..

Mike

[Mark Hennessy]

Confusing, isn't it

"100V line" is quite separate from "line array" or "line source" speakers. Sometimes the two are found together; i.e. a line source speaker has a 100V line input, but "normal" speakers can have 100V line inputs, and line source speakers can be 8 ohms or whatever...

The main difference between a line array and a conventional speaker is the dispersion pattern. And of course, for PA use today, it's one way to get scarily high sound levels

https://en.wikipedia.org/wiki/Line_array