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

I've got my bum tweeter rebuilt, the cabinets expanded and sealed and I have all my x-over components in hand- the last thing I need is the foam for the mids. I just can't locate anything 1/16' thick and I'm not going to order a whole sheet for the tiny amount I need -the freight cost more than the foam- so I'll shelve this project for a while and keep my eyes open for something that will work. In the meantime I'll be recapping my optimus 5b's!
 
Foam for mids

Buttercup said:
I've got my bum tweeter rebuilt, the cabinets expanded and sealed and I have all my x-over components in hand- the last thing I need is the foam for the mids. I just can't locate anything 1/16' thick and I'm not going to order a whole sheet for the tiny amount I need -the freight cost more than the foam- so I'll shelve this project for a while and keep my eyes open for something that will work. In the meantime I'll be recapping my optimus 5b's!
Click to expand...

If you have 1/8" foam or the like, you can cut it 1/8" wide and lay it on a flat surface on it's side and cut it in half with a razor! I did this on the last ones I refoamed. The strips are just over 3" long, should be easy enough.
 
Hey Buttercup i have a piece here that i have left over its a small piece, but good for your two mids.... i can mail it to you if you want? it should be good enough, you will just have to cut the straight pieces as its a crooked piece....

Let me know i could mail it out today if you wish....
 
robmorin said:
Hey Buttercup i have a piece here that i have left over its a small piece, but good for your two mids.... i can mail it to you if you want? it should be good enough, you will just have to cut the straight pieces as its a crooked piece....

Let me know i could mail it out today if you wish....
Click to expand...

That's a very generous offer- I'll pay it forward! PM sent!
 
videolady201 said:
52 turns off should be fine. If you have a MM that has a mh scale and can test inductance, I would use it to confirm it, that would be best!
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I am now in the process of recapping my crossovers but i have noticed i have 3 coils with wire, two have a cloth covering, one has the copper wire exposed. one is marked 0.2mhf, one is marked 3.0mhf and the is a very small coil this i am ignoring. I do not see any markings .3 mhf. which coil are we unwinding? also i notice on the coil with 3.0mhf the two copper wires coming out of the coil cross over each other where they leave the coil and touch . any info would be appreciated.
 
I have now realized its the inductor coil stamped at 0.2mhf is the one we are dealing with, do i just unwind it to .15, i see the 4029 had a 0.3mhf
 
The tier 1 upgrade paper is ready for all who have an interest. It is in PDF file format and can be downloaded at the link below. Please contact me with questions
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Just confirming ohm resistance at speaker terminals. I see in your report you stated after completing new crossovers ohm reading should be 6.5-6.6 this is of course for the 4029,s my first completed crossover reading is 8-8.2, hopefully this is what you would expect with the 4024a,s considering it is a 8ohm woofer.
 
I'm not the britest bulb on the planet, but it appears I may be able to test caps with my meter? There is a setting "CAP" with "40unF and 4nF", does that make sense? Also, what symbol am I looking for to test mH? I don't see mH anywhere on my dial.

Thanks!!
 
Copa1934 said:
I'm not the britest bulb on the planet, but it appears I may be able to test caps with my meter? There is a setting "CAP" with "40unF and 4nF", does that make sense? Also, what symbol am I looking for to test mH? I don't see mH anywhere on my dial.

Thanks!!
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Your right on with the caps ,that will test them, you will be surprised at how far off all the new ones are, i had to to test quite a few to get values i needed, also put some in parallel. I found the caps that read numbers like 14 were off by quite a bit. My meter has an L setting for inductance which really helped with my coil
 
System Impedance after Mods

sendust said:
Just confirming ohm resistance at speaker terminals. I see in your report you stated after completing new crossovers ohm reading should be 6.5-6.6 this is of course for the 4029,s my first completed crossover reading is 8-8.2, hopefully this is what you would expect with the 4024a,s considering it is a 8ohm woofer.
Click to expand...

I would expect to see an ohm load just about one ohm higher, around 7.5-7.6. It would not hurt to double check and look at the crossover again and just see that all looks ok.
 
Can you send an image? I don't recall mine crossing. I have an extra set at work I'll check out tomorrow. As for the coil, I'll have to check that out tomorrow as well, thought I had that info here at home.
 
videolady201 said:
I would expect to see an ohm load just about one ohm higher, around 7.5-7.6. It would not hurt to double check and look at the crossover again and just see that all looks ok.
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I checked the crossover and saw nothing amiss, i did the second crossover independently and did not use the first as a reference, just in case i made a mistake with the first. Again i ended up with a resistance of 8.2 ohm. Im not sure why i didn't get the 7.6 but i thought if anything i may have gotten 8.6 considering my speakers are 8 ohm. The sound is amazing and after the complete tier 1 upgrade it has been quite impressive. Also i tried the speakers raised and on the floor and am happy to say you were right on with your information, there is a noticeable improvement on the floor. Thank you for all of your advise to date and hopefully at some point i may improve to the second tier upgrade.
 
Copa1934 said:
Can you send an image? I don't recall mine crossing. I have an extra set at work I'll check out tomorrow. As for the coil, I'll have to check that out tomorrow as well, thought I had that info here at home.
Click to expand...

It ends up that the one that crosses is not the coil we are changing, it was the 0.2 coil. I guess on the 4029,s it has a 0.3 coil.
 
I'm trying to follow VL's tier one upgrades and I've run into an issue.

The plan calls for replacing:
33uf with a 14 uf
10 uf w/ 8.2
2.75uf w/ 4 uf
.3mh w/ .15

My values on the 4024A are different

I have:
2mh / 2.2 uf / 2kR for the tweeter
coil ? (can't read the value) / 10uf / 8kR for the mid
22uf / 3mh / for the woofer

As I see it my resistor values are different as well as some capacitor values... can someone that's completed the 4024A x-over take a look and straighten me out as to what needs replacing with what!!!
 
Mach 1 4024a Tier 1

Buttercup said:
I'm trying to follow VL's tier one upgrades and I've run into an issue.

The plan calls for replacing:
33uf with a 14 uf
10 uf w/ 8.2
2.75uf w/ 4 uf
.3mh w/ .15

My values on the 4024A are different

I have:
2mh / 2.2 uf / 2kR for the tweeter
coil ? (can't read the value) / 10uf / 8kR for the mid
22uf / 3mh / for the woofer

As I see it my resistor values are different as well as some capacitor values... can someone that's completed the 4024A x-over take a look and straighten me out as to what needs replacing with what!!!
Click to expand...

Replace the 22uf with 14uf (Woofer)
Replace the 3mh coil with 2.7mh or wind down (Woofer)
Replace the 10uf with 8.2uf (Midrange)
Replace the 1.4mh coil with 1mh coil or wind down (Midrange)
Replace the .2 mh with .15mh (Tweeter)
Replace the 2.2uf with 4uf (Tweeter)

Follow all the other instructions in the Tier 1

Set both Midrange and Tweeter dials to 0db (4024a) or -3db (4029) for the new 0 db setting. This is because of the resistor values used in each model, the 4024a using more resistance does not need to be turned down but the 4029 does. If you want your dials at 0db on the 4029 model, you can replace the 2 ohm mid resistor with 8 ohm and replace the tweeter's 1 ohm with a 2 ohm resistor.
 
This thread has gotten so bloody long (not complaining) so finding what I'm looking for has been a challenge.

As it relates to both 4024 and 4029, are the leads from the crossover reversed for mids and tweets? I thought I saw mentioned where this was the case from the factory, but not necessary with the Tier-1 upgrades. Is this correct?

Thanks!!!
 
videolady201 said:
Replace the 22uf with 14uf (Woofer)
Replace the 3mh coil with 2.7mh or wind down (Woofer)
Replace the 10uf with 8.2uf (Midrange)
Replace the 1.4mh coil with 1mh coil or wind down (Midrange)
Replace the .2 mh with .15mh (Tweeter)
Replace the 2.2uf with 4uf (Tweeter)

Follow all the other instructions in the Tier 1

Set both Midrange and Tweeter dials to 0db (4024a) or -3db (4029) for the new 0 db setting. This is because of the resistor values used in each model, the 4024a using more resistance does not need to be turned down but the 4029 does. If you want your dials at 0db on the 4029 model, you can replace the 2 ohm mid resistor with 8 ohm and replace the tweeter's 1 ohm with a 2 ohm resistor.
Click to expand...

ok VL now you have lost me, in the tier one report it never mentioned replacing the 3mh with a 2.7mh. Is it needed and a noticeable change, if so i will remove the crossover and make needed changes.
 
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