[morzh]

Why would I want AK10 to drive a cone speaker? It is a high impedance load output, and that is what it should be driving. Which is what it will drive.
This said, I am sure that if one made a transformer to reconcile the 01A plate resistance with the cone speaker, it would make it work, though notsure how well.

[radiorich]

Hello mike,
I wonder what impedance far as the speaker would you need or would using a audio matching transformer .
Sincerely Richard

[morzh]

The one it was intended to work with, the horn, I think no transformer is needed.
The one with the cone...yes it would and to make it look presentable a box could be built with an audio xfmr in it, that would connect between the radio and the speaker. Plain stained wood box, 4 screw terminals.

[Arran]

Mike;
If you are thinking of a dynamic speaker like most radios use to this day, then you would be quite correct about needing a transformer. I have a speaker from a Radiola 33 where someone fitted a 5'' P.M dynamic inside, and it has an output transformer fitted, so either the original speaker failed, or they just decided to re-use the cabinet. I also have a Radiola 100A, with a broken cabinet, that I picked up for the 8'' speaker inside for the Radiola 33speaker, and it's a high impedance cone speaker, with a tar filled paper cap and choke in series with the voice coil. The A.K speakers would be similar, either the horn, or cone speakers, without the chole and capacitor. https://antiqueradios.com/forums/viewtopic.php?t=444395
Regards
Arran

[morzh]

Arran,

So are saying that the AK speaker would be a high Ohms unit with a filter (BTW, why are they using the filters?) inside it, so it should work directly, same as the horn type?

I have no experince with these so far.

[RodB]

I remember the RCA 100 I worked on was 1800 ohms and connected with a 0.05 mfd cap to the output tube. There was a capacitor filter network block inside the speaker. I replaced the guts with a modem 6 inch high fidelity and transformer. Worked beautifully and cosmetically it was the same.

[Eliot Ness]

The correct speaker for the AK breadboard is a horn speaker, preferably an AK, although a Music Master with the wooden bell would look pretty spiffy with it.

   

[Arran]

Mike;
I don't believe that the A.K speakers have chokes, or capacitors inside them, I think it's basically like an old headphone diaphragm in the base. The cone speakers are also high impedance, the drivers I think are similar to the Radiola ones, but without the choke and capacitor, in the one A.K cone speaker I have apart the mechanism was inside a cloth bag, the speaker worked so I left it alone. I was mostly concerned with repainting the metal housing, and stand, so I removed the cone and driver as a unit, and reinstalled it after I repainted the housing.
Regards
Arran

[MrFixr55]

Hi Folks, I am differentiating between a "Cone" speaker and the modern dynamic speaker.  Here was the evolution:

• Marconi era to about 1924:  Headphones, 1,000-2,000 ohms.  Worked with crystal radios and early tube sets.
  
• Early 1920s: Horn speakers, 1,000-2,000 Ohms, the sound producing element was very similar to a headphone. Requires more power than a headphone, at least one stage of tube amplification was needed to drive the horn.
  
• Early - mid 1920s: Magnetic Cone speakers.  Speaker driven by a magnetic reed "motor".  Speaker impedance was between 1,000 and 2,000 Ohms.  Required more power than either horn or headphones.  Usually required a "power tube", UV120 (35mW at 135V), UX112A (30 mW at 90V, 115mW at 135V) or UX171A (125mW at 90V,370mW at 135V, 700mW at 180V) Examples include A-K Model E, E2, E3; RCA 100, 100A, Crosley Musicone, Timmons Talker.  RCA 100A, 100B and 103 included an LC filter to filter out highs to lessen the harshness caused by distortion.
  
• 1926 to current: Rice-Kellog Dynamic Speaker.  Low impedance (1.0-16 Ohm) cylindrical "voice coil", acting with / against an electromagnet or permanent magnet "field".  Requires a transformer to match to tube' stated load resistance.  requires more power to drive than a magnetic cone speaker of the same cone size.  However, of all of the above speaker types, the dynamic speaker delivers the best fidelity.
  

Hope that this clarifies my position.

[MrFixr55]

Yes, bottom line is that an AK Breadboard or 20 Big Box drove a horn speaker, no transformer, no filters. A US Postage stamp titled "Radio entertains America" showed an AK9 type radio with a wonderful Burns horn speaker where the horn had brown translucent celluloid "petals".

To best of my knowledge, only the RCA magnetic speakers, specifically the 100A, 100B and 103 used the LC filter. My AK E2 cone speaker uses solely the reed "motor", no filter. The earphones, horn and cone speakers were connected between output tube plate and B+. Polarity was important, as wrong polarity gave lower volume and demagnetized the poor quality magnets available at the time.

"Socket powered" sets used an L-C coupling method, similar to RC coupling where the choke was in series between the output tube plate and B+ and the cap was in series between the output tube plate and speaker. The other speaker lead was connected to the output tube cathode.

[morzh]

So, can AK model E speaker be used with the UX201 output amp?

This one or others from E series?


   

[morzh]

OK, steel wool is in, microfiber cloth is in.
Waiting on Howard. Ppromissed on Friday.

[radiorich]

Hello mike,
Is that howard's restore a finish ?
I also like using howard's Bees wax polish too .
Sincerely richard

[morzh]

Yes, Restor-a-Finish. Is promised for tomorrow.

[Paul Philco322]

I have had good luck with those products Rich, the wax is especially handy for a qwik polish up. The restore a finish is not a "miracle" product but good at spiffing up a tired finish that has not gotten to the refinish line.

Good luck Mike. Paul