B&W DM4, Celestion HF1300 questions/guidance

[Wyndwalker]

Greetings all

Wyndwalker here from North Carolina(USA)

Picked up a pair of B&W DM4(1972 version, I believe)

One of the Celestion HF1300 tweeters is shot

I've disassembled the speaker and the voice coil is broken/gone

The version I have is the 16ohm version(large magnet and little red 16 sticker next to mounting hole)

I see an ebay seller from France as something similar but in conversations with him, seems he only has the 8ohm version
He says this is the voice coil only

Can that 8ohm version be used in my 16 ohm?

Assuming it is just the voice coil piece he has
I would attach to my diaphragm and hope I can solder those tiny wires
and reassemble the unit

Speaking of reassembly
I mistakenly took the speaker apart from the front(opps)
I have a general idea of how it goes back together
but am a tad confused on the proper order of the 3 cardboard gaskets

What I'm calling Gasket 1 has some small slits, so assume this goes on first so the lead wires can come out
What I'm calling Gasket-2, is very thin
And what I'm calling Gasket-3 is thicker(same as G-1 but without slits)

Is that the proper gasket arrangement?
or do G-2 and G-3 need to be reversed

Thanks
Any/all help/guidance welcomed

 

[planet10]

There are a number of HF1300 versions… 8/16 ohm small/large magnets at a minimum.

You need to use the same one.

dave

 

[Wyndwalker]

There are a number of HF1300 versions… 8/16 ohm small/large magnets at a minimum.

You need to use the same one.

dave

Thanks
But I've scoured the interwebz and finding a 16ohm voice coil, is like looking for a unicorn.

Anyone know a source?

 

[planet10]

At this point in history you almost have to wait for someone else with an HF1300 16Ω speaker to have it die and part it out.

You might contact Jerry at Falcon to see if he can suggest replacements.

dave

 

[Wyndwalker]

Curious as to what the difference are in the 8 verses 16 voice coil
More wrappings?
does the size of the magnet have any bearing on impedance

I have the whole speaker, just the Voice coil portion is gone
Though I did manage to save most of the wire from it
wonder if possible to rewind myself....

 

[planet10]

Voice coil can be manipulated a number of ways to change impedance.

Magnet doesn’t significantly affect impedance.

I have a small magnet HF1300, not sure what the impedance is. I also have some dead big magnet ones. I had thots of trying a butterfly transplant.

dave

 

[boswald]

Coles Acoustics is making 8 & 16 ohm versions. The faceplate is more modern and flush mountable without the grill plate, so I don't know if that works for you. They may have coil assemblies.
I really enjoy the 1300s in my Dittons, and if we can organise a small order, perhaps we can reach any minimum order requirement they may have. I have wanted to try a new construction with a pair.I had asked Falcon and a few other British resellers, they said get ahold of Coles, it isn't worth their trouble.
So write to Coles, see what can be done. Used hair-thin wires in old stock(ebay etc) are too sketchy, not worth any trouble adapting if there's any difference in behavior.

 

[high123bid]

Did Celestion HF1300 and HF2000 use ferrofluid, please?

I am rebuilding the above for a pair of IMF speakers. Did Celestion HF1300 and HF2000 use ferrofluid, please?

Even if they possibly did not, does anyone have experience with "retrofitting" ferrofluid to tweeters?

 

[system7]

I am dead certain ferrofluid wasn't even around back in those days.

More than you could possibly want to know about the HF1300 here:

Spendor BC1

Looks like 16 ohm version of HF1300 in the Spendor BC1. It behaves a lot like a cone tweeter. But maybe goes lower. Originally a compression driver. The Coles 4001 was originally an ITT microphone. Weird, huh?

I suspect adding the Kerosene in ferrofluid might be a bit unpredictable with old adhesives. These days, manufacturers design for it, more often than not.

 

[planet10]

I am dead certain ferrofluid wasn't even around back in those days.

+1.

The HF1300s i had that i disassembled (not from an IMF) did not have ferrofluid.

dave