Author Topic: Speaker Cone replacement sources?  (Read 2801 times)

0 Members and 1 Guest are viewing this topic.

Offline Wil_BloodworthTopic starter

  • Regular Contributor
  • *
  • Posts: 200
  • Country: us
Speaker Cone replacement sources?
« on: November 18, 2023, 11:52:31 pm »
The cone on this speaker completely disintegrated.  Any suggestions on where to find a replacement cone?  The voice coil is 15mm / 0.6" in diameter.

The output transformer measures 84 Ohms on the primary side.

1932012-0

Thank you,

- Wil
 

Offline wasedadoc

  • Super Contributor
  • ***
  • Posts: 1730
  • Country: gb
Re: Speaker Cone replacement sources?
« Reply #1 on: November 19, 2023, 12:03:52 am »
1.  It is the resistance of the speaker's coil which matters, not that of the output transformer.  Is there any info printed on the back of the speaker's magnet enclosure.

2.  I would have left more of a complete circle of the original and just glued a new paper cone to it.  That is use the original voice coil.

3.  Whatever you do it is tricky to keep the voice coil centred so that it moves freely in the magnet gap and does not rub against the magnet.
 
The following users thanked this post: Wil_Bloodworth

Offline CaptDon

  • Super Contributor
  • ***
  • Posts: 2500
  • Country: is
Re: Speaker Cone replacement sources?
« Reply #2 on: November 19, 2023, 12:57:38 am »
There are some antique radio forums as well as antique radio shows one being in Kutztown Pennsylvania. Google up speaker reconing. It isn't cheap!!! There are several who specialize in exactly the style of speaker you have. Back in the day speaker magnets were only a few ounces unlike my pro audio stuff where the magnets today run 17 pounds and more!! The neo magnets are a life saver for old dogs like me who still have to carry their own gigging amplifiers. Neos cut as much as 60% of the speaker weight compared to the older stuff. I just sold two Peavey 12" Black widow baskets with open voice coils. A guy from the Netherlands bought them and he does reconing in that country!!
Collector and repairer of vintage and not so vintage electronic gadgets and test equipment. What's the difference between a pizza and a musician? A pizza can feed a family of four!! Classically trained guitarist. Sound engineer.
 
The following users thanked this post: Wil_Bloodworth

Offline Jeff eelcr

  • Frequent Contributor
  • **
  • Posts: 368
  • Country: us
Re: Speaker Cone replacement sources?
« Reply #3 on: November 19, 2023, 02:29:35 am »
I have no idea, what speaker cone are you asking about?
Manufacturer if known, size, ID and OD, depth all in inches. Metric if not US made.
Proably made in USA, paper cone only? No spider, no wires, no other parts.
Jeff   
 
The following users thanked this post: Wil_Bloodworth

Offline amyk

  • Super Contributor
  • ***
  • Posts: 8928
Re: Speaker Cone replacement sources?
« Reply #4 on: November 19, 2023, 03:45:01 am »
You can try making a replacement out of thick paper. It's unlikely the original would've provided very high quality sound either.
 
The following users thanked this post: Wil_Bloodworth

Offline CatalinaWOW

  • Super Contributor
  • ***
  • Posts: 5886
  • Country: us
Re: Speaker Cone replacement sources?
« Reply #5 on: November 19, 2023, 04:15:46 am »
You might try these folks. 

http://www.thespeakershop.com/home/speakerrepair.html

Have you thought about replacing the whole speaker.  It would be relatively easy to transfer the transformer to the frame of the new speaker
 
The following users thanked this post: Wil_Bloodworth

Offline Wil_BloodworthTopic starter

  • Regular Contributor
  • *
  • Posts: 200
  • Country: us
Re: Speaker Cone replacement sources?
« Reply #6 on: November 19, 2023, 05:26:54 pm »
Amy:  Yes, that was my first thought... but my second thought was, "You're terrible at arts/crafts so don't waste the time/energy/money".

Jeff:  Sorry, there are no markings anywhere on the speaker of any kind.  The only thing I know is that it is a 5" speaker from circa 1946.

Fixing this 80-year-old speaker is probably quite a bit above my pay grade so I think I'll have to just replace it until I learn how to repair one correctly.  The entire radio isn't worth $25 so I'm not about so spent a ton of money on something almost no one wants.

I've ordered a few replacements from Amazon to see if I can find something similar.

- Wil
 

Offline Jwillis

  • Super Contributor
  • ***
  • Posts: 1740
  • Country: ca
Re: Speaker Cone replacement sources?
« Reply #7 on: November 19, 2023, 09:16:04 pm »
The cone on this speaker completely disintegrated.  Any suggestions on where to find a replacement cone?  The voice coil is 15mm / 0.6" in diameter.


Try Ebay. This one is in the States. they have the wires preinstalled which is handy. Check the depth from spider to top of basket.
 5" paper cone


Rebuilt a couple myself. The old glues used  can usually be softened with acetone. Contact cement works pretty good if you can't get anything else. Just messy to use.
Build the surround before gluing the cone . The surround will help keep the cone pressed in place and centred.
The surround might be tough to find. try to separate as best as you can. These can be made with heavy card board or non-oiled gasket material. Carefully separate the surround from the basket and make a copy. Or you can stack construction paper to build a new surround.
Does the voice coil move freely ?  If not you may have to replace the spider as well. Try to salvage the coil if you can.

Regards





 
The following users thanked this post: Wil_Bloodworth

Offline Wil_BloodworthTopic starter

  • Regular Contributor
  • *
  • Posts: 200
  • Country: us
Re: Speaker Cone replacement sources?
« Reply #8 on: November 19, 2023, 09:34:46 pm »
Try Ebay. This one is in the States. they have the wires preinstalled which is handy. Check the depth from spider to top of basket.
 5" paper cone

Thank you for the link sir!  I will keep that in mind.

I didn't realize it would cost so much to re-cone a speaker.  Unfortunately, I cannot justify all the extra $ to rebuild this old speaker... unless I was just bored and wanted something to do (which is a perfectly good reason).

I was able to purchase two, fully-functioning 8-Ohm speakers delivered to my door for the same price as this single 5" eBay cone.  We shall see how that goes!

Maybe if I was restoring a radio that meant something to someone or it was a rare/valuable radio I might "splurge" but this is my first restore and I just want to "get it working again" and feel like I actually accomplished something.

Thank you,

- Wil

 

Offline wasedadoc

  • Super Contributor
  • ***
  • Posts: 1730
  • Country: gb
Re: Speaker Cone replacement sources?
« Reply #9 on: November 19, 2023, 11:53:11 pm »
Unsolder one of the wires on the secondary of the transformer so that you can measure the resistance of the voice coil.  Supposedly a rule of thumb is that if you multiply that resistance by 4/3 you get an estimate of the speaker impedance *.  You may find that really old speakers are closer to 3 Ohms impedance than 8.

* https://www.diyaudio.com/community/threads/lower-than-normal-impedance-in-vintage-speakers.397034/post-7299723
 
The following users thanked this post: Wil_Bloodworth

Offline Wil_BloodworthTopic starter

  • Regular Contributor
  • *
  • Posts: 200
  • Country: us
Re: Speaker Cone replacement sources?
« Reply #10 on: November 20, 2023, 12:41:59 am »
Unsolder one of the wires on the secondary of the transformer so that you can measure the resistance of the voice coil.  Supposedly a rule of thumb is that if you multiply that resistance by 4/3 you get an estimate of the speaker impedance *.  You may find that really old speakers are closer to 3 Ohms impedance than 8.

* https://www.diyaudio.com/community/threads/lower-than-normal-impedance-in-vintage-speakers.397034/post-7299723

I de-soldered the output transformer and measured the voice coil as you suggested.  It read 3.0 Ohms.  Therefore, based on the 4/3 rule, I estimate this is a 4-Ohm speaker.

That was a fun experiment!  Thanks.

- Wil
 

Offline Jwillis

  • Super Contributor
  • ***
  • Posts: 1740
  • Country: ca
Re: Speaker Cone replacement sources?
« Reply #11 on: November 20, 2023, 12:55:22 am »
Try Ebay. This one is in the States. they have the wires preinstalled which is handy. Check the depth from spider to top of basket.
 5" paper cone

Thank you for the link sir!  I will keep that in mind.

I didn't realize it would cost so much to re-cone a speaker.  Unfortunately, I cannot justify all the extra $ to rebuild this old speaker... unless I was just bored and wanted something to do (which is a perfectly good reason).

I was able to purchase two, fully-functioning 8-Ohm speakers delivered to my door for the same price as this single 5" eBay cone.  We shall see how that goes!

Maybe if I was restoring a radio that meant something to someone or it was a rare/valuable radio I might "splurge" but this is my first restore and I just want to "get it working again" and feel like I actually accomplished something.

Thank you,

- Wil

Ya.When the speaker gets that small it generally isn't worth it. Depends on how close to stock you want to take the restoration. Larger than 8 inch may be worth the effort and cost. Finding complete vintage speakers under 8 inch that are a close match is much easier than above 8 inch. It has a lot to do with the numbers sold in the market at the time.
The ones I rebuilt were 10 inches and up. So the cost and effort was justifiable.
 
The following users thanked this post: Wil_Bloodworth


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf