S G Brown H1 horn loudspeaker.

[RadioBlues]

Hello!
I just bought myself an S G Brown horn loudspeaker and since I am new to restoring, I was wondering if anyone could give me some advice on how to handle/what to do with this wonderful device
Any help will be much appreciated.

Best regards,
Pedro

Moderator edit: Moved from this thread: https://www.vintage-radio.net/forum/...ad.php?t=65905

[newlite4]

They look brilliant on a shelf display, but I suppose it wouldn't hurt to run an ipod through them, the output is low enough not to damage the coil and it would make a good talking point.
Neil

They do sound pretty awful compared to modern 'speakers, just think of it in the 20's, must have been brilliant!

[RadioBlues]

Haha, thank you both for your posts
I would love to do that! just for the kicks of it haha
I completely fell in love for it when I saw it but its in a pretty bad condition as it shows in the pictures, any advice on where I should start refurbishing/restoring it? any tips or knacks on how to do it? regard me as a complete newbie haha



Best of regards from yours trully,
Pedro Magalhães

[Heatercathodeshort]

The coil should read around 1-2k ohms. You will need a matching transformer if you wish to use it in place of a conventional speaker. They sound 'hollow' but it's surprising how your hearing becomes accustomed to it. Have fun, John.

[RadioBlues]

Thank you John,
I see, but there is a round metal inscription in between the two frontal "pistons" that reads 4k ohms, should I take this into consideration?

Best regards,
Pedro

[AC/HL]

They are the terminal posts to connect to the speaker, in this case a 4K version.
All being well, you should be able to measure something around this resistance between them.
If you haven't got a meter, a battery should produce a noise if all is well.

[RadioBlues]

Thank you Bill,
Do I have to open the base in order to measure it or is there another way?
By the way, there are 3 holes around the wooden base (as you can see on the first picture) that I do not know what they are for, any ideas of what they can be?

Best regards
Pedro

As said before pop a Walman/Ipod etc onto the terminals, there is a knob to adjust for 'best' sound (it will never be very good). That said they do look very good when restored, I am thinking of puting a modern 3" 'speaker at the horn/flare joint in mine to make it better (sound wise) filling the horn bit with padding to absorb the rear sound.

[RadioBlues]

Oh, I see, if everything's ok there should be music haha
I know this must sound rookie-like but what kind of cables am I looking for in order to pop in the ipod? I have access to them in my faculty but I'm not quite sure what to look for.
Merlin, that sounds like an awesome idea! but how would you power that modern speaker? (please excuse me if I am making any rookie mistakes).

best regards

[RadioBlues]

Hello!
I bring an update I've measured the Ohms and it's 3.9k! I even heard a faint sound when I was measuring it with my multimeter!
What's the next step?

Best regards,
Pedro

[wireful3]

Pedro,

You could connect it to the phone socket of a transistor radio but with a direct connection it would be very quiet. I have done this myself using the lead from an old set of phones. I just cut the lead before the Y division and separated the wires.

To get a reasonable output you need a matching transformer. This may be hard to find. I am not sure how much experience you have but the output transformer from a valve radio can be used. With the speaker connected to the input connections and the radio to what would have been the output connections. It might not help you very much because I am not sure whether old, faulty, valve radios are as easy to find in Portugal as in England.

It looks quite an interesting speaker and from my experience you are very fortunate to have the coil working. Most I have found have open circuit coils and so completely silent.

Good luck,

[AC/HL]

The three holes in the wooden base would be to mount it on top of a radio, which in those days would be in a wooden case with a flat top.

[RadioBlues]

Thank you both for your reply,
John, I'm not very experienced but let's see where this will get me, I know I can do it with your help haha, in case I can't find one of those valve radio trasformers, I've heard that it's "easy" to build one yourself. Have you ever heard of such working for these models?

Bill, haha I wasn't managing to figuring out what they were for, thank you for clarifying me.

Best regards, yours truly

Pedro

[wireful3]

Hello Pedro,

I think your first move is to try the direct connection, it might show that something works.

You might be able to find on-line suppliers who have a transformer but I am not confident about this. It would only be worth doing if the direct connection gives some music even if very faint.

It is possible to make your own transformer but I am afraid it is not easy. It needs hundreds of turns of very fine wire on a bobbin and transformer laminations.This wire is probably more difficult to find than an old radio with a suitable transformer that could be used.

There is another way that I have not tried myself but others have said it works. This is to use a transformer intended for reducing the mains voltage to work low voltage (about 6volts) equipment. One might be found in an old adapter for transistor radios. It would have to be the old type that is usually heavy. The modern adapters will not be any use because they work in a different way.

There may be someone else on the forum who has done this and could help

Let us know what happens with the direct connection.

Regards

[RadioBlues]

Hello John,
Thank you for your reply, it helped a lot!
I'll be sure to keep you updated and try the direct connection and then tell you how it went
Actually, I did as you suggested and cut an old set of earphones before the Y but there are 4 wires, two on the right and two on the left, one green one red, one copper and one blue (respectively) any idea on the color code?, Will it hurt the horn if I test the cables in pairs on the terminal posts?

Best regards,

Pedro

[wireful3]

Hello Pedro,
First I would like to reassure you that testing by trying pairs separately will not harm the horn. Your lead must have been from a set of stereo phones, when I did it I had some old mono phones so it was easier to see what to do.

I don't know the colour code but try first by using the copper as a common lead and first the red lead, then the others in turn. Remember that the signal might be very quiet. You should find that two of the wires give an output. If this happens you could join these two wires together and then to the speaker.

If you get nothing at all then try the pairs in turn as you said.

Regards

One pair may be quieter than another, this will be the two 'positives' only giving the difference in audio, i.e. no signal if in mono. Best to try all combinations, for the loudest. Or look at the wires in one of the cut off earphones and use those two.

[RadioBlues]

Thank you both for your reply,
John, I see, I did test them all as you and Merlin suggested and I definitely heard music, those are the good news haha, the bad news are that the music was so low that you basically had to put your head inside the horn to only hear a whisper. I though that maybe this was because of the earphones so I bough myself a mono cable and a jack and let's see if this helps. I'll post an update as soon as I can but I believe I will still need your guys help using the transformer as I didn't understand how you are to use it much less how to add it.
Thanks for all your help so far.

Best regards,

Pedro Magalhães

[RadioBlues]

Greetings,
Well, the mono definitely helped (although just little bit) at least it's easier to set, and after I messed with the volume variable I could immediately see the potential that this amazing piece has! this has set up the fire burning stronger haha!

Best regards.
Pedro