How to make a loudspeaker sandwich cone DIY

[Freedom666]

Hello,

I will post here some information on how to do by yourself a conversion of an existing loudspeaker driver with a simple paper cone to a more sophisticated sandwich cone.

It can be also done with plastic cones but with thinner foil and special glue.

There is abundant information on this already posted by me on this thread:

How to make a loudspeaker sandwich cone

Hello, here I want to describe how I do make a sandwich cone with aluminium foil. This can be done with normal household aluminium foil and normal glue you can buy everywhere as "universal glue". You need a scissor and the materials like aluminium foil, glue and the loudspeaker. The foil can...

www.diyaudio.com

So to say I am doing this since the year 2000 and you can achieve good acoustic results doing this modification to existing drivers. Sometimes it ads a resonance at 4 or 5khz -the region where hard cones often have problems with break up modes but I found out that these resonances can easily be tamed with proper filtering being it analogue or digital active or passive EQ.

You use simple household aluminium foil and available glue like pattex or uhu. You need a scissor.

You cut pieces of aluminium foil into tart like parts and glue them overlapping onto the loudspeaker paper cone. Its more difficult on the backside of the cone but it can be done with some experience.

There will be also measurements before and after modification.

This kind of mod is also usable for fullrange drivers because the foil is mellow aluminium foil (not duraluminium like in D.A. Barlows designs) and the core is damping paper. Usually you end up with a fullrange driver with less resonances and much more stability of the cone. Better transients overall.

This is most easily checked with an A/B listening test doing this mod with a pair of drivers - one being modified and the other not - and using the balance knob of your amplifier playing a mono record. Then you switch between the channels and you get an impression of what this tweaking is capable of.

 

[restorer-john]

Oh dear.

 

[Penelinfi]

Sounds interesting. I used to do similar things, modding cheap speakers. I wouldn't do it with more expensive stuff or if it sounded good already. My favourite was scanspeak revelator cone mods.

Will be interesting to see how these new Leak speakers measure . Sandwich cones are relatively common these days. My current speakers have some, and I've found interest in the Sony APM speakers.

 

[restorer-john]

Will be interesting to see how these new Leak speakers measure . Sandwich cones are relatively common these days. My current speakers have some, and I've found interest in the Sony APM speakers.

Sony's original APM and the Leak's original Sandwich have virtually nothing in common.

The early Leaks were an absolute abomination IMO and the quad drive Sony APMs were interesting, but ultimately a complex solution in search of a problem.

 

[Penelinfi]

Sony's original APM and the Leak's original Sandwich have virtually nothing in common.

The early Leaks were an absolute abomination IMO and the quad drive Sony APMs were interesting, but ultimately a complex solution in search of a problem.

I didn't say they were in common with one another though. It's still sandwich construction

Anyhow, sometimes I find it's fun to do things out of interest than to do nothing because everything's already been solved and the perfect item has already been made

 

[Jim Taylor]

Please show detailed before-and-after measurements. The difference should show the improvement, no?

Jim