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Realistic Mach 1 (4029) upgrade x-over vs stock

b3733366 said:
Right, and to elaborate ...

My understanding of this, having done the mod myself late in the game (there was already 120 pages *before* I discovered the thread), is that:

1) VideoLady201 (VL) did the Tier 1 work based upon 4029.

2) Later VL examined the 4024A and determine that the drivers (woofers in particular) were pretty much acoustically/electrically equivalent. Differences were mostly in power handling, i.e. the woofer in the 4029 has some type of metal voice coil former giving it greater power handling over the 4024A (which has a paper voice coil former if I recall correctly).

In other words VL determined the Tier 1 mod could also be performed on the 4024A. Everything the same.

The only complication is that when you compare original x-over component values between 4029 and 4024A most of the values *are different* ... so from 4024A to 4029 the latter has greater power handling *and* a modified x-over (component values).

Hence the Tier 1 mod applied to a 4029 and 4024A are the same "in the end" (as RS Steve puts it), but how you get there may differ. If keeping original coils you have to do unwraps on all three 4024A coils whereas for 4029 (I think) you have only to unwrap one coil.

---

Now at the risk putting the clouds back into what I hope is now a clear sky ...

The Mach 1 x-over resembles more a quasi-2-way than a true 3-way. The tweeter and the horn (mid) "overlap" in the highest frequencies.

VL worked on a true 3-way x-over and reported even greater improvements over Tier 1. Unfortunately the 3-way x-over never got published.

I mention this for the benefit of those that might otherwise be confused, especially if encountering mention of the 3-way after 70-80 pages! :)

--

"So I'm wanting to do the x-over upgrade to my 4024a's. But I noticed that some of the cap values are different from what the tier 1 mod from VL stated. Will this mod work for the 4024a. Just wanting a solid yes or no. Thanks"

All that fluff works out to a solid ... YES!

LOL
Click to expand...
Actually VL published a preliminary network for the Tier-3 upgrade, it's in the VL thread. It's not a 3-way but a 4-way actually. VL also posted a mockup of the speaker which ran two woofers (with different xover points) and then the stock mid and tweeter.
 
Well I wish it were true but there's no way I'm ever going into those +120 pages to find it. :scratch2:

Should be easy to just leave out a woofer and do a three way ... but was the speaker he did bigger (bigger volume)? If so the x-over values might be wrong for the Mach 1 box.

--

BTW - this is my first horn ... well my second, my main speakers Tannoy Arden are technically horns if I understand properly ... but anyway first separate horn. I gotta say it can sound very realistic at times, not everything but then it just plays something and, nice, so realistic! And even when not doing magic sounds just fine, not harsh at all. Great speaker!
 
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b3733366 said:
Right, and to elaborate ...

My understanding of this, having done the mod myself late in the game (there was already 120 pages *before* I discovered the thread), is that:

1) VideoLady201 (VL) did the Tier 1 work based upon 4029.

2) Later VL examined the 4024A and determine that the drivers (woofers in particular) were pretty much acoustically/electrically equivalent. Differences were mostly in power handling, i.e. the woofer in the 4029 has some type of metal voice coil former giving it greater power handling over the 4024A (which has a paper voice coil former if I recall correctly).

In other words VL determined the Tier 1 mod could also be performed on the 4024A. Everything the same.

The only complication is that when you compare original x-over component values between 4029 and 4024A most of the values *are different* ... so from 4024A to 4029 the latter has greater power handling *and* a modified x-over (component values).

Hence the Tier 1 mod applied to a 4029 and 4024A are the same "in the end" (as RS Steve puts it), but how you get there may differ. If keeping original coils you have to do unwraps on all three 4024A coils whereas for 4029 (I think) you have only to unwrap one coil.

---

Now at the risk putting the clouds back into what I hope is now a clear sky ...

The Mach 1 x-over resembles more a quasi-2-way than a true 3-way. The tweeter and the horn (mid) "overlap" in the highest frequencies.

VL worked on a true 3-way x-over and reported even greater improvements over Tier 1. Unfortunately the 3-way x-over never got published.

I mention this for the benefit of those that might otherwise be confused, especially if encountering mention of the 3-way after 70-80 pages! :)

--

"So I'm wanting to do the x-over upgrade to my 4024a's. But I noticed that some of the cap values are different from what the tier 1 mod from VL stated. Will this mod work for the 4024a. Just wanting a solid yes or no. Thanks"

All that fluff works out to a solid ... YES!

LOL
Click to expand...



**This is what I dug up for the 4024a crossover change out of my files.


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
 
b3733366 said:
Well I wish it were true but there's no way I'm ever going into those +120 pages to find it. :scratch2:

Should be easy to just leave out a woofer and do a three way ... but was the speaker he did bigger (bigger volume)? If so the x-over values might be wrong for the Mach 1 box.

--

BTW - this is my first horn ... well my second, my main speakers Tannoy Arden are technically horns if I understand properly ... but anyway first separate horn. I gotta say it can sound very realistic at times, not everything but then it just plays something and, nice, so realistic! And even when not doing magic sounds just fine, not harsh at all. Great speaker!
Click to expand...
I don't recall specific dimensions. One would have to extrapolate dimensions going by the known dimensions of the drivers themselves. Plus I don't recall depth, so that could be an issue as well. VL worked on the assumption the woofer normally would require 4cuft minimum. But with one functioning as a mid-bass driver that could change things.
 
RS Steve said:
**This is what I dug up for the 4024a crossover change out of my files.


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...
This is only my personal take on the matter, but I have my mid set to almost -6db at present. I have 4024a with the full VL treatment (Tier 1&2). My horns are 4029 and running absent of ferrofluid. With my next build I plan to replace the ferrofluid, but only if I do a "VL Mach One". I'm leaning towards doing the Tier-3 system, but volume is an issue, i.e. not knowing the actual volume NOR knowing if the mid-bass has it's own chamber (most likely).
 
Ok, so I found VL's Tier one mod, and I completed it. Seems to be a little more subdued in the mid-range department now. But I do have two pairs of 4024a's. I was thinking about custom building two cabs and putting a pair in each box. Any thoughts on this?
 
Pair of woofers in each cabinet?

Any chance you got the wiring wrong? Really have to dig, but there was quite the discussion about drivers being out of phase, as well as the phase being different going from the 4024 to the 4029. So it's possible you have the phase wrong with the mid, that happened with me, but it was due to my not using the correct terminals on the pot, before going to the driver. After switching the wires the mid not only came back to life, I had to turn down the pot. There could be other issues at play, but I don't recall anyone describing this other than when phase was incorrect.
 
I believe I have them wired correctly. I thought that that is what I had read. That by doing the cross over mod, unwinding the coils and such. That it would mellow out the mid-range section a bit.

Yes, a pair in each cab, along with the tweeters and mid-ranges. Would I need to have separate chambers for each woofer?
 
Probably better definition and transient performance in separate chambers. But they'll probably go an octave lower together in one. You must have tried them stacked by now, top ends against each other. You probably will not improve on that. Building new stiffer cabs may offset the drawback but they'll still be faster if you separate them even then.
 
Stacked they're crazy. The bass is to die for. I have one set of Mach One left, just shy a woofer at the moment, and not sure now why. Oh well.
 
Could someone show me where to buy the 10uf 50v capacitors for the Mach one speakers? Forgive my ignorance but the ones I see have the two wires sticking out of one end and I need wires coming from both sides. I checked Parts express. Also will I only be needing four caps?
Thanks
 
any poly film or non-polar electrolytic cap with a rating of 50V or higher is fine. most caps nowadays are rated at 100-400V....

the voltage isn't an issue, it's the capacitance (microfarad) value that is important to match, and again, I wouldn't restore them to stock, I'd definitely do the videolady mods. it results in a much flatter frequency response and better sounding speaker. it does reduce the "sensitivity" slightly by flattening out the 6+ DB humps in response in the midrange.....
 
rxonmymind said:
Could someone show me where to buy the 10uf 50v capacitors for the Mach one speakers? Forgive my ignorance but the ones I see have the two wires sticking out of one end and I need wires coming from both sides. I checked Parts express. Also will I only be needing four caps?
Thanks
Click to expand...


I ordered mine from partsexpress.com.
 
michiganpat said:
any poly film or non-polar electrolytic cap with a rating of 50V or higher is fine. most caps nowadays are rated at 100-400V....

the voltage isn't an issue, it's the capacitance (microfarad) value that is important to match, and again, I wouldn't restore them to stock, I'd definitely do the videolady mods. it results in a much flatter frequency response and better sounding speaker. it does reduce the "sensitivity" slightly by flattening out the 6+ DB humps in response in the midrange.....
Click to expand...
Thanks for the input & I will do all VL suggested upgrades. Unfortunately the PDF wasn't able to download on my Droid RAZR phone so I don't know exactly what Caps to buy. The felt, sawing & midrange 1/16 neoprene I understand.
But WHERE can I buy quality caps that have the wires sticking out of both ends? I see a lot of caps with two wires sticking out of the same end.
I wouldn't mind spending a bit for quality caps as I'm keeping these speakers.
Thanks
 
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