2234 recone kit in E 145 baskets

[MoD]

I had feeling that I am missing something. I was presumptioning that longer coil will give less overdumped speaker and by that more bass extension.
But your observation about ME150 is right.

So that leaves little maneuvering space. It seem logical to try to find extension rings (long shot), so I could go with "original" recone kits, or go straight for LE 15 recone kits.

[MoD]

They are home.

They are also hommage to fix it what You have laying around. The best are spiders. They are from some huge speaker, because they do not fit in the frame and surface that should be glued is protruding on the sides. One who put this together simply glued one convenient lower part of the roll.

But they are working. I will play a little bit with them until i buy some recone kits.
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Speaking of recone kits, SoundSpeakerRepair closed permanently. I have their D130 kits which I find good. I have found post where one member of this forum stated that he had to recone one of two his LE15 and couldnt hear the difference.

Such a shame. I was looking for other LE 15 recone kits and it seems all of them have aluminum wire instead of copper voice coil.

Does anybody maybe have a two E 140 extension rings to spare?

[MoD]

So...Time fly...I have changed a lot of ideas of what to do with those speakers. In some point I was playing with idea to buy this aftermarket recone kit;https://reconingspeakers.com/product...recone-kit/and to make make extension rims myself to accommodate those recone kits, but that is a very long shot....So to cut this never ending story, I think, I am going to buy one of these recone kits;https://reconingspeakers.com/product...le15a.htmlWhat do You think, which one? They look the same to me, both with wrong alluminium ribbon wire, instead copper...

[MoD]

At Last... I Ordered LE 15A recone kits from Speaker exchange page. ( https://reconingspeakers.com/product...et-recone-kit/ ) for my E 145 baskets. They clame, that voice coil is wounded with coper edgewound wire, so mms should be ok. They allso claim that provided spider is stiffness C, so medium stiffness. Is that right stiffness for LE 15A spider?

[RMC]

MoD,

RE LE15A recone in E145 basket

I don't intend to rain on your project, i assume you know what you are doing and the risks involved.

This is a "unorthodox" mix you are trying to achieve, but if you can make it fit and work correctly great for you.

Since these are aftermarket recones there's a possibility the tolerances might be less than perfect? Anyway you're on your own for such recone job.

Good luck.

Richard

[MoD]

RMC, I know.But, original E 145 kits can not be mounted any more on my speakers because they are missing extension rings. I was contemplating diy extension ring, I was even given measurements (on this site) but, necessary thickness aluminium plate can be bought here only in 2m x1m dimenssions and cost 800 euro. I was thinking buying square rod, and machine bend it to circle of appropriate diameter, weld it and then machine it, but there is no such machine in my town...So, only plausible way to go is try to fit LE15 recone kit. LE 15 shoul have mms about 97 grams, and E147 about 55 grams. And aftermarket recone kit... who knows..., I will weight them upon arrival, and then will decide what next;Flux density in both LE15 and E145 is similar, LE 15 has lover Fs, but wont play as high as E145. LE 15 spider has (I think) less stiffer spider, so even if aftermarket recone kit will have mms between 55 and 97 grams, that will be ok, because it will produce speaker with caracteristics between those two speakers, and one can work with that. I think so any way...Thank for thumbs up, it will be needed :-)

[RMC]

MoD,

RE "LE 15 spider has (I think) less stiffer spider"

True, but it applies to spider and surround. The LE15A Vas parameter of 736 L represents a large volume of air and as such it is more compliant (the opposite of stiffness), compared to a smaller Vas number leading to a stiffer suspension.

So that data gives an indication about a woofer's suspension (more or less flexible), plus it is also used to determine the proper box volume for a speaker, along with the driver Qts.

Richard

[MoD]

I understand. I assume risk is not big due to existence of LE 15H speaker, which to my (limited) knowledge is nothing more then E 145 without extension rims with LE15A cone assembly. Real question are aftermarket parts. I have read other experiences with aftermarket recone kits, and few people said that aftermarket recones had higher Fs than original. That could be caused by smaler recone mms, or stiffer spider. (or both) Speaker Exchange guy said that their aftermarket recone kits voice coils are edgewound with copper wire, and have spider stiffness C. I do not know what spider stiffness should be in LE15A but since 136A and 2235 models have stiffness C I assume LE15A has the same. All I can do now Is wait for recones, then I will measure them, and then I will go from there...Regards...

[MoD]

So, recone kits has arrived. Took it friend of mine who has precise scale. We put on scale; one cone (have already glued foam surround on it), one dust cup, one voice coil. Weight; 75 grams. I was told in local recone shop that during glueing there goes about 15 grams of adhesives. So 75 + 15 equals 90 grams, and MMS should be 97 grams. So I will be about 7 grams off, probably more because surround mas should be taken of this calculation, and i do not know mass of surround.So, I am thinking of taking piece of brass wire 2mm diameter, make it round and glue it inside of top part of voice coil former. What do You think?

[1audiohack]

Hello MoD;

Since you have some unknowns why not assemble the cone kits in the frames and before you install the dust caps run them a bit and see where they are, and then decide if and how much mass to add.

I don’t recall if these are going to be used as subs or used in a multiway speaker?

Barry.

[Earl K]

So, recone kits has arrived. Took it friend of mine who has precise scale. We put on scale; one cone (have already glued foam surround on it), one dust cup, one voice coil. Weight; 75 grams. I was told in local recone shop that during glueing there goes about 15 grams of adhesives. So 75 + 15 equals 90 grams, and MMS should be 97 grams. So I will be about 7 grams off, probably more because surround mas should be taken of this calculation, and i do not know mass of surround.So, I am thinking of taking piece of brass wire 2mm diameter, make it round and glue it inside of top part of voice coil former. What do You think?

@MoD

MoD, the 75 grams measured weight obtained from a scale doesn't represent a drivers MMS

What you obtained by weighing your recone kit on a kitchen scale is more accurately called the drivers MMD.

If all the parts for a fully assembled recone kit are included in the weighing ( including the tinsel leads and glue for the dust-cap and voice-coil bobbin ) then the weight would be more accurately called the MMD.
- The weight of the glue, to glue the spider ( and the surround ) to the frame is not included in either the MMD or the MMS.

MMS = MMD & ( the so-called ) "air-load" expressed in grams ( which also includes a tiny bit of the compliance's resistance to movement expressed as grams and then added into the MMS ).

Depending on the 15" woofers compliance ( stiffness ) that "airload" can be anywhere from 15 to 20 grams ( approximately ).
- The "stiffer" the suspension ( compliance ) the greater its contribution will be to the final ( all-inclusive ) "airload".

A 15" woofer having a MMS of 97 grams should have an MMD in the neighborhood of 82 to 85 grams.

Your measured weight of 75 grams is only 7 to 10 grams short ( of which a goodly portion will be made-up for, by adding glue for the dustcap-cone and glue for the spider to VC assembly and then glue for the cone to VC assembly ).

As Barry has suggested, assemble what you have and then run DATs 3 ( or similar ) and use the software to see where you are at for all the TS parameters needed for box tuning ( before adding any more weight ).

[MoD]

@ 1audiohack;It is going to be used in two way with 2344 horn and 2425 compression driver. I will send speaker to local speaker service. Deal is to measure Fs before dust cup is attached.@ Earl K;I tought, I new basic obout T/S parameters, but, I was wrong. Had no idea about MMD and airload. But with what You said, it looks MMS with airload should be ok. With that, if speakers will not measure right Fs I think it will not be due to MMS, but because wrong suspension compliance. And voice coil. After market coil winding is 0,375" and should be 0,313". At this point I think I will not add mass to speaker, but...

[1audiohack]

Hello MoD;

I think, if it were me, I would leave them as light as possible for the best midrange extension and EQ them to your taste.

Barry.

[MoD]

Yes, I think that would be the smartest way.Today evening I will be taking out rcf parts recone kits from baskets and tomorrow going to recone shop with the lot. I am going to save rcf parts recone kits, I have one rcf 15" frame, and plan to do some experimenting. some day.