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Mach One 4024, 4024A, 4029 Information and Upgrades!

Thanks for the quick reply for the quick reply video lady..

I also removed the horn and put a new piece of foam as per your doc, the only thing i noticed that was different was on mine i had a clear plastic O ring that went around on the outside of the foam part... i did not remember seeing that in your doc, so i thought i would let you know.... i can send pic when i do the next speaker if you want...

have a great evening..
 
O-ring

robmorin said:
Thanks for the quick reply for the quick reply video lady..

I also removed the horn and put a new piece of foam as per your doc, the only thing i noticed that was different was on mine i had a clear plastic O ring that went around on the outside of the foam part... i did not remember seeing that in your doc, so i thought i would let you know.... i can send pic when i do the next speaker if you want...

have a great evening..
Click to expand...

Hello,

Yes, please send a picture. I assume someone added the o-ring. Many with 4024a speakers have had them apart and no o-ring was in them. I really would like to see the images. The o-ring is to dense and will limit the response of the horn. Looking forward to you pictures.:scratch2:
 
Oh drat!

I think i freaked up the horn... i went through the upgrade for the horn on one of my mach ones(4024A). Now the horn is less pronounced, as compared to the non re-foamed one...???

I guess i might have messed up the re foaming... i use 1/8 of an inch rather than 1/16 as i could not find any 1/16.. would this make a difference?

any ideas what i should check for?

i also replaced the caps on the same unit at the same time....

is there any software programs i can use to test with any kind of proper tones?

Am i able to buy that 1/16 foam anywhere online as a few places i went to only have 1/8 inch...

Thanks...
 
My camera is not the best, but here are 2 shots, one is with the O ring on the side and the other is with the O ring in the, not sure what to call it? the black part of the casing...

The O ring is transparent plastic..
not sure if you can see my foam, that i replaced...

what do you think..

do i then remove that O ring thingy?

Thanks...
 

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O ring

robmorin said:
My camera is not the best, but here are 2 shots, one is with the O ring on the side and the other is with the O ring in the, not sure what to call it? the black part of the casing...

The O ring is transparent plastic..
not sure if you can see my foam, that i replaced...

what do you think..

do i then remove that O ring thingy?

Thanks...
Click to expand...

OK. Is the O ring flat or is it round? It looks like a spacer to keep the dome from buzzing or touching. If it is flat, how thick is it? If it is around 1/16" thick and the foam you put on is 1/8" thick, I would put the O-ring/washer back in the unit. This will make up for the extra foam thickness. Also, the horn will not be as loud/sharp as it use to be, that's what the foam damper is for. If you had a new horn is would be more like the one you just did. Also, what new caps did you put in? What brand/values?
 
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Thanks once again for the quick reply... the O ring is flat, transparent and rigid plastic and its very thin, i guess about 1/16" or thinner. as you can see it went around the outer perimeter of the foam..

to be safe i will order that 1 /16 foam.....

As for the sound difference, i did not think it would be that drastic of a difference..

i will re do with the foam in your link, better safe than sorry, when i do should i still put the O ring back?
Also BTW, not sure if its a big deal, the O ring is slightly sticky, not sure if it was glued anywhere before it came out, it was not difficult for it to come out

i wonder if anyone else has encounter this ring?
I hope i can contribute to this thread somehow....

Thanks very much..
 
O-ring & Foam

robmorin said:
Thanks once again for the quick reply... the O ring is flat, transparent and rigid plastic and its very thin, i guess about 1/16" or thinner. as you can see it went around the outer perimeter of the foam..

to be safe i will order that 1 /16 foam.....

As for the sound difference, i did not think it would be that drastic of a difference..

i will re do with the foam in your link, better safe than sorry, when i do should i still put the O ring back?
Also BTW, not sure if its a big deal, the O ring is slightly sticky, not sure if it was glued anywhere before it came out, it was not difficult for it to come out

i wonder if anyone else has encounter this ring?
I hope i can contribute to this thread somehow....

Thanks very much..
Click to expand...

That would be the best thing to do, replace the foam with the 1/16" foam. As for the spacer I would put it back in the unit based on what I have seen. Can you try to get better pictures and also a picture of the dome assembly it's self. I think the sticky stuff on the ring and in that area is the melted / rotten foam that was in the mid.
 
replacement tweeter

One of my tweeters measures open- Is there a source for an original or suitable aftermarket replacement?

This for the 4024A model- SH-2, 8 ohms, 1.5KHz - 18KHz, nominal 5w, music 10w. max-
 
okay i will get another camera and take a better photo of the pieces... but i can only do after work today....

So i will post around 7pm after dinner :)

Thanks...
 
Replacement Dome Mach 1 4024a

Buttercup said:
One of my tweeters measures open- Is there a source for an original or suitable aftermarket replacement?

This for the 4024A model- SH-2, 8 ohms, 1.5KHz - 18KHz, nominal 5w, music 10w. max-
Click to expand...

I have tested this one and it fits and the ohm load is the same, the material is the same as is the look. It requires just a few mods but will work fine. The foam ring has to be removed and your leads soldered and taped in place.:yes:

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-531
 
Just a note, when caps go bad the tweeters often get lower frequencies than intended, and thus will sound louder. So replacing caps alone would have made the tweeters sound softer as the lower frequencies would no longer be fed to them. So between the new foam and new caps it makes sense that the tweeters would be softer. Also do keep in mind that you also spared them severe damage as the lower frequencies would have caused permanent damage over time.
 
hope these are better for you.. VL
one pic is of the casing with my refoam, but i ordered today new 1/16 inch foam, so i will redo that again
one pic is of the O ring/spacer itself
one pic of the dome assembly with O ring in it an done pic without it in it...

If you wanted me to take apart the dome assembly, i was a bit scared as it does not seem to come apart easily, and i did no want to break anything..
Anything else you need?

btw, with my Fluke multimeter connected i get 7.4 ohms as the impedance off the input terminals of the speaker.

thanks
 

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Mid Driver Mods

robmorin said:
hope these are better for you.. VL
one pic is of the casing with my refoam, but i ordered today new 1/16 inch foam, so i will redo that again
one pic is of the O ring/spacer itself
one pic of the dome assembly with O ring in it an done pic without it in it...

If you wanted me to take apart the dome assembly, i was a bit scared as it does not seem to come apart easily, and i did no want to break anything..
Anything else you need?

btw, with my Fluke multimeter connected i get 7.4 ohms as the impedance off the input terminals of the speaker.

thanks
Click to expand...

Please see the picture. No foam should overhang the Mid cup where the dome sets. There should be a small recess where you cleaned the old foam off. Try to make sure your foam is no wider than this recess and that it does not overhang any edge of that recess area. On your units the clear washer (O-ring) needs to be left in place. The newer models have a molded in ring, so keep those in your units. Also, the foam is to thick. It would be good to redo them with the 1/16" foam tape!:yes:
 
ok, great when i get the new foam i will do a better job, the 1/8 inch was a little hard to curve around the recess..

as for the O ring, no adhesive needed? just clean off sticky stuff and put back?

Thanks for all your help''

Have yourself a great evening....

:)
 
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