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

[RayW]

Point is no driver change is required to get different results, just one error in the production of a single piece that would otherwise, upon physical inspection would appear to be the same. :scratch2:

Yup. Done incoming and outgoing QC, too. Was there known to be variability in the Mach 1 woofers? I'm curious here, not trying start or imply anything. Just catching up.

2..The cabinet being Acoustic Suspension and of a very hi Q in this case, provides the largest portion of the compliance load for this driver. Even with changes up to a 30% mark, has almost no affect on the output.

Good point.

3..You don't know what my goal is and I prefer to speak for myself and would appreciate it if you didn't try to do it for me.

Sorry, I wasn't trying to speak for you. Just pointing out that you are approaching things from a different angle than we usually see around here. I did not mean to say or imply that that is good or bad, just different. And I certainly did not mean to comment on your goals. I'm just watching the numbers go by.

 

[RickeyM]

Yes VL, do stay on topic. I don't own Mach Ones, but I am a fan. I'm also a fan of modding speakers to overcome their initial limitations .

 

[Dan ʕ•ᴥ•ʔ]

There are knowledgeable people here who have built speakers on a far grander scale than the Mach Ones. They are trying to help the process along, not deter it. Unless you have something to add that is on topic, don't post in this thread.

 

[robmorin]

So i reassembled my modded Mach One, all seems great except the horn gives a distorted or slight buzz at a volume of 10 watts... ???almost like something is loose, or maybe touching the cone in the voice coil... i will take apart and check again....

VL, i hate to be a pest, but are you sure i should not have to glue the voice coil back onto the magnet? as there did seem to be some brownish glue when i removed it...

Not sure what to do next??



It's a holiday here in Quebec today... so i have time to work on my babies...


Thanks..

 

[marc mc]

They are what they are. I have owned 2 pairs and really did not consider them anything approaching musical. But I don't think they were ever intended to be.

I bought both pairs at a junk store for $30 each. I was just getting into subs and thought the bass drivers looked good. The first pair I set up and played for about an hour put them in the laundry room and sold a year later. The second pair were used as mains on the HT for about a year and then sold.

I understand why guys like them. Their big, bad and cheap. But lets face it they are what they are. And they were made for loud Rock and Disco and can't play much else very well. I also have a pair of Optimus 7's and they are 180 degrees in the opposite direction sounding. Their smooth, balanced and very musical and need zero mods to sound that way. They will also play nearly as loud but without the BOOM.

The Mach 1's create a sound that is unique to them and lets face it that can't be right.

marc mc

 

[robmorin]

So here are some pics of the horn disassembled. if you loo closely you can see a bit of the old adhesive or glue residue... its difficult to come off..

sorry for the quality of the pics its the best i can do for now...

Also i noticed that when putting the voice coil back on magnet... it(the voice coil) can move from side to side a bit, and touch the sides of the round slot in the magnet, is this s problem? As i was thinking maybe during assembly the coil can shift over to one side and actually touch the side of the round grove... this is why i was thinking some type of adhesive was used to make sure it was center first before assembly??

Thoughts, ideas, suggestions?

 

[videolady201]

Mid Range Buzz

So i reassembled my modded Mach One, all seems great except the horn gives a distorted or slight buzz at a volume of 10 watts... ???almost like something is loose, or maybe touching the cone in the voice coil... i will take apart and check again....Thanks..

The glue is not needed for function. It may have been used to set the VC centering in a Rub & Buzz production test.
You can do the same as you reassemble the mid driver. You can hook it up to your amp, just the mid driver, no crossover, just straight wired to your amp. Use a 1khz test tone from a CD, etc. Set the volume/voltage to the driver at 2.83 volts AC. Move the dome of the mid driver side to side on the magnet until the tone is pure with no buzzing sound. Once you have found this position, set the face of the horn over the dome and replace the screws. If it's tone is not pure after tightening the screws, start the procedure over. You may have to do this a fews times to get it right. Newer models has alignment pins so the VC was self centering. Also check that the new foam you put on does not overhang the gap that is molded into the housing. Also, make sure yours has the spacer in place, it provides the clearance between the compression chamber and the dome.

 

[robmorin]

ok i will give it a shot and get back to you....

Thanks for the quick reply..

 

[robmorin]

ok, cool, so what idid is put a couple dabs of contact cement on VC then i turned on the tone at 1kz,and adjust teh VC til the tone was as clear as my 46 year old ears could tell.. then i let the glue set for 10 mins, and re-assembled , and now its much better...


There is a very noticeable difference too in the bass, comparing modded cabinet and un modded.. after the 12x4 inch whole was cut, its actually less boomy, well to my ears anyways....

however i did notice some vibrations a bit at a test tone of 50 hz, so i will have to see what is loose , so to speak...

On another note i swapped woofer, remember i had the farting one, it still farts in the other cab... so i guess the woofer itself is messed up somehow..
so thats it for now..

got to go have a beer, and relax a bit , then maybe tackle the other mach one..

Have a great day all..

 

[jamesm007]

There are knowledgeable people here who have built speakers on a far grander scale than the Mach Ones. They are trying to help the process along, not deter it. Unless you have something to add that is on topic, don't post in this thread.

VideoLady has built speakers on a much grander scale than the MachOnes her/him self. This is not an 'open' project in the works. This is a very much a completed project (Really I don't know "how complete"... but its clear its his/her project) by VideoLady who has done lots and lots of hard work and testing and listening. She/He needs 'no' input, 'no' management other than forum rule management. No one else stepped up to the plate and offered to help make the very popular MachOnes better, did they? Some may have a personal bias against them, or pride. If someone has either, its best to keep negative stuff in email.

I emailed VideoLady with a question when she/he emailed me back they had their real name on the email. When I found some information about this person. Believe me this is a 'highly' experienced speaker designer, and that's very relevant to this project. And don't forget she/he is already way ahead of us, and is only walking us through the upgrades... I would not write it, if it was not true. And would email this person if you have math problems. There are hundreds of people reading this project of hers/his to discredit the person is not good for the project, it forced them to take apart a driver.

In this case if she/he was showing impossible things to all (in a program... don't get me started on 'programs') and a bunch or red flags went up... I can understand the 'major' concern. Seems, a lot of miscommunication happened this is why relevant to the project I feel its best left to email to clear up things that don't make sense. Then make a public disclosure about the problem. This would have prevented the rather extreme act of tearing a driver apart. At least 'extreme' to me, but not to this person... Geez, says a lot. And to be honest glad she/he did, now I know I don't have to tear mine apart. For a short time, when I valued them 'very little' I almost tore the woofer apart to see why it never blew?

But Ive had my fun, I am not modding mine right now; I will latter. I was given a pair of Bose 10.2 (original) and they have a few cabinet nicks, and a pin hole in one of the foams; but the foam is still good! I have been working on them. I have not even listened to them yet! That's how busy I get. I did buy a tweeter plate for my MachOnes on eBay and was starting to work on one of them and then said 'why', I have a PF18tl sub, DT BP10 speakers, the Machs won't replace my setup... I have had my glory with them, when they were the speaker of choice when your 16-25 years of age :thmbsp: But I also went to all the shops on Woodward Ave here in MI back when I had them and knew what hi-end sound was. But I quickly learned to get Hi-end sound at loud levels cost big bucks. Until around 1990... When a lot of speakers flooded the market with the knowledge of the NRC testing behind them. Just at the same time I had some money...

OK the Radio Shack Catalog. It had speakers that cost more and less than the MachOnes that were advertised with a different buyer in mind. Look at all of the ads for the MachOnes, who were they made for. BabyBoomers who loved Rock/Disco and us younger guys drooled over them but many could not buy them... Really almost all of RadioShack catalogs show BabyBoomers near the sound systems, these systems were made for the person in 25-35 age group who may be able to afford them. And us younger guys (13-23) drooled over them lol... and now want that thrill... have fun enjoy them as/is or make em sound better for your taste. I already had my 'blast'. And may have being serious done slight damage to my hearing now... I grew up in the age of loud volume, plenty of power... not good for your hearing, keep care of you ears if your young serious:yes:

Now a question. The original MachOnes horn had a plastic insert in them. I saw this at a co-workers house 20 years ago. I noticed his woofers looked different, and his horn had something in it, and it did not say "liquid-cooled". I wonder if this piece makes a big difference and why it was removed...???

I will just... for the most as I have been for the pasts weeks.

 

[Copa1934]

That's not too much of a dare. I do that for a living. Yes, I've done the changeover from different driver vendors. I know what is involved. I'm not saying test every driver before doing the mods. However, when a difference in Levc of a factor of 10 shows up, that should send up some flags. VL answered that it was because one of the was not actually measured so the program filled it in. No worries.

However, not knowing where you're starting from means that when you get to the end you can't retrace your steps. If there were, in fact, 2 different woofers that were used in the 4029 and the modifications are designed around 1 of them then they may not work out as well for the other.

Usually in a scientific environment you measure, then change 1 thing and measure again. Then change 1 thing and measure again. This assures repeatability and easy to follow documentation. VideoLady is going at it from a different angle. She's got a goal in sight and what matters is getting there. That's fair. The problem is that when she says the goal is 11Hz Fs then you have to measure for that. If she did it by adding 50g of mass to the cone that's great. But if you don't have the same driver she does then adding 50g of mass may or may not get you to the 11Hz Fs. If you don't start at the same place she does then taking her route may not get you to the same destination. That's why I asked about the specs on the modified driver before the modifications.

This is the kind of response I have respect for, it isn't condesending, it doesn't come across as an attack, etc. Too many people don't read the thread, they simply glance and pick and choose what they don't agree with. I've been following the entire thread and for me it has been, for the most part, handled in a scientific fashion. I don't feel that multiple changes have taken place all at once, but in steps. And if not all the time I would say most of the time.

I agree with you completely that if you make more than one change you have very little chance of figuring out which change had an impact or the greatest impact or any impact at all. I have a couple favorite examples of when science doesn't go as planned "Real Genius" and "Medicine Man". Sometimes things slip by us, we are human after all.

 

[Buttercup]

I'm a novice tweaker, as I suspect most folks on this site to be. The technical aspects of this thread are sooo far over my head but, I am enjoying making the mods to my Mach I's and whether the mods turn 'em into world beaters or turd eaters doesn't matter much... I'm having fun pursuing my hobby.
Thanks VL

 

[HomeBody]

... Really almost all of RadioShack catalogs show BabyBoomers near the sound systems, these systems were made for the person in 25-35 age group who may be able to afford them....

Baby Boomers & __________!
Anyone here remember the Yuppie Generation..?

 

[jamesm007]

I remember a little now. In my teens these were people as my oldest brother who was in his 30's, early 30's. Heck I don't even know how old I am anymore... but was that yuppies? I think the show 30 somthing was even for them. Could be 100% wrong as I was into my MachOnes at the times lol....

 

[HomeBody]

There are knowledgeable people here who have built speakers on a far
grander scale than the Mach Ones. They are trying to help the process
along, not deter it. We don't need Mach One flags being waved in every
other post. Unless you have something to add that is on topic, don't post.

(Sobbing)...Geez...I wanted to post about my mach ones somemore...sniffle, sniffle
Would someone bring me a tissue, please:tears:

 

[gyrene]

"Baby Boomers & __________!
Anyone here remember the Yuppie Generation..? "
Yeah they're the ones that drove a cup of coffee up to $4.85,right? And bottled tap water at a buck a throw.

 

[HomeBody]

"Baby Boomers & __________!
Anyone here remember the Yuppie Generation..? "
Yeah they're the ones that drove a cup of coffee up to $4.85,right? And bottled tap water at a buck a throw.

And probably frowned upon anything w/the Realistic label....

 

[videolady201]

STA-84 Picture

And probably frowned upon anything w/the Realistic label....

STA-84, that is a nice receiver!

Had a little mishap yesterday. A GMC truck drove through our front show room and tore the building up. I'll post a few pics later. Always something else to do/deal with....:scratch2:

 

[Sasquatch2]

Hope nobody was hurt VL.

 

[jamesm007]

>I'm making some assumptions here regarding the 15" woofer's cone area

Yea the MachOnes woofer is a tricky woofer to deal with. This thread is for MachOne info and upgrades well this pertains to info and is not part of anyone's project...Go back and look at my posts I am a huge MachOne fan and owner of 30 years of the same pair of 4029s...

Again (I know you get tired of hearing it) long ago I noticed 'all' other 15" woofers looked bigger than the MachOnes. I measured them 30 years ago against another 15" woofer and found the MachOnes woofers are smaller, much smaller and this made me happy as it meant the woofer was at least a bit better sized for the cabinet volume. Now if you don't know you should that a woofers stated diameter does not tell how much area the woofer really has, its (making things simple so I don't lose anyone) the total distance across in the middle including surround, frame... This does subjectively give the MachOnes the bold look as the woofer does not look too big for the cabinet, moreover it looks the right size subjectively if you don't know about speakers design. The latter Machs or RS 15" woofers had larger cone area.

I don't have another 15" driver to measure its cone diameter if you do check and see; I did long ago and it is smaller! This is why MachOnes need special foam, the cone area is smaller than standard (if there is such a thing) 15" woofers and is very thick 'beefy' :thmbsp:. And the new bezel around 4029s may or may not add to the beefy look, now thats a close call and very personal.

Going purely by very poor memory most, 15" woofers I measured were (?) ~12-13" across, and the MachOnes is 11.1/4"... just for those, like those who don't own them know. I have always thought of the MachOne woofer as being something between a 12" and 15" a little closer to a 15" :scratch2:

Anyways IMO this is what gives the MachOnes woofer that meaty tough look and differentiates it from others.

A photoshop refoam, much quicker and easy (altered picture )