Mackie 24.8 Service Manual / Schematics

[DavidWBatts]

Thank You Enzo

[DavidWBatts]

My problem with this 24 x 8 mackie i just bought is aux 1 and 3 work part of the time they seem to drop the signal down to almost nothing and a loud spike will bring them back but they soon drop out again i talked to a engineer that has seen this problem in other mackie mixers he tells me that the cause is a 72 cent op amp chip i need to find out what the chips # is so i can try to repair this has anyone run into this i only paid 400 for this mixer so i dont want to take it back i can not find another mixer of this caliber for this price
Thanks

[Enzo]

Your guy may be right, but I'd have to say I doubt it. Most op amps are not intermittant. The solder under them might be cracked, but that isn't the part's fault. And if it is a solder problem, replacing the part will surely cure it, but so would simply resoldering the old one. Not only that, but to change the IC, you have to take the board out, and doing that refreshes all the ribbons, see below. In other words, in my theory, it is not the IC that was bad, it was the act of changing it that restored operation.

My experience with mixers in general and Mackies in particular leads me to suspect three things first.

First is ribbon cables. I forget the innards of this one, but so many Mackie mixers make subassembly boards, then connect them together with wide ribbon cables. The ribbon connectors fail. (They get oxidized or electrically dirty) Usually pulling the ribbon connector off the header and then pushing it back on cleans the contacts and refreshes them. And you need no schematic for that, just pull each ribbon half way off and push it back down. And don;t skip the inconvenient ones.

second is insert jacks. Might not apply to your specific trouble, but each channel has one and often the outputs upper right corner have them. They get dirty and lose contact. Usually a spray of contact cleaner into the jack and poke a plug in and out a few time to spread it around solves this.

third is push switches. The little push switches than everyone uses for things like channel assign, pre/post assign, mute, PFL, whatever. I find they often get dirty. I also find that if I take a breath, sit down with pliers, and pop all the caps off them, I can then go down the row and squirt cleaner into each, then push it a few times. The little square posts have enough space around them that a squirt of Deoxit will get inside. Try just poking each switch on the channel sending to your bad aux and see if any wake up. I see 15 buttons per channel

SLiders are also a major source of trouble, but they affect the main outs, not specific aux sends. At least mostly.

[DavidWBatts]

Thank you again i have spent the last 4 hours with contact cleaner so i am reasonably sure its not a dirty pot or switch however you may be right on the ribbon thing or the insert so i will run those in the morning i have not pulled it apart yet so i have a plan of attack now

[km6xz]

Mackie has a series of ribbon cables that were required to be changed as a set under warranty years ago when the 8 bus came out. The boards are very reliable otherwise and once a year cleaning the normalizing jacks: any inserts. Be sure not to use Contact Cleaner but a deoxidizer. Solvents labeled as contact cleaner are often the exact opposite of what is needed. Be sure it says Deoxidizer on the label. The most common is the Craig Laboratories De-Oxit in various flavors. In Europe, Cramolin R-5 or CRC 60. Don't squirt into the shafts of pots, it washes the lube out and the pot loses its smooth feel. There are pot lubes but none are effective in returning the smooth damped feel of the original pot.

The odds of the engineer being right about an IC are possibly 1 in 1,000,000 with that symptom and if that is his first guess, save yourself a lot of trouble in the future and not ask him for technical advice or hire him to engineer a project for you. He is clueless or trying to deceive you, either one is bad. If the drop out was a channel, sub or main, look for the oxidized insert TRS jack to be cleaning or the ribbon cable. If the cable set is original and it is an early serial number, order the replacement cable set and change everything. You could repair a cable if you identify the culprit by cutting off the connector and crimping on another connector on the end that is flaky, but eventually more than one cable will need to be repaired due to intermittent cable header connectors.
$400 is a good price for the board, it will last forever.

[Enzo]

Good point. When I say contact cleaner, I have in my mind my can of Deoxit, But i really should be more precise.

[DavidWBatts]

Thank You guys i did the cable thing and it fixed aux 1 aux 3 is still having the same problem i suspect you guys are right and the cables need replace so i have won the first battle but still fighting the war
Thanks Guys

[vkostin]

Guys, I need schematic of power supply of my 24\8 bus, anybody have it for help good people? Thanx

[Jazz P Bass]

Attached.

[vkostin]

Thank you! Very much!

[locust_tree]

Thank You guys i did the cable thing and it fixed aux 1 aux 3 is still having the same problem i suspect you guys are right and the cables need replace so i have won the first battle but still fighting the war
Thanks Guys

David - I created an account because I'm having the same problem on aux send 6 (and sometimes 4, the same knob controls both). If you solo the aux masters you can really hear it. Quiet / distorted sound or sometimes no sound at all, and a good signal spike will sometimes "pop" the aux open and then it will function normally. Other times you just can't get sound out of that aux. I have a lot of outboard parallel effects and having working auxes is very important to my particular workflow with that desk.

I suspected a failing IC or a solder joint going cold as well but the responses in this thread lead me to believe it's the dreaded ribbon cable problem. It's worth mentioning that aux 6 behaves the worst between channels 9 and 16, which lends more support to the ribbon cable theory as I believe the ribbon cables run in 8-channel banks. What did you do to fix this?

[filomarino]

Hi, i need to remove the armrest of a 24.8 Is there a way to do that... its glued? Any advice great appreciated.

[Renatoloks]

Hello Friends, please someone has schematics complete Mackie 24.8? I tried to open the links but does not work My Mackie does not modulate the Meter LR, but normal audio. I also want to know if you know where I can buy new faders, all are failing. Thanks

[Jazz P Bass]

http://music-electronics-forum.com/t15640/
Contact Loud Technologies for parts.

[EmosDad]

But until we get that working right, get your serial numbher, and contact Loud Technologies (owner of Mackie) and ask for the drawings. They will probably ask you to agree not to post them online. But at least you will have them.

Hey folks!
How are you all doing?
My name is Robert and I am new to your forum; I too am looking for the schematics/service manual for a Mackie 24 8 console.....

Is there any possibility that someone on this board could email them to me directly???

I contacted Loud Technologies and here's what they said..... "We are sorry to hear about the troubles you are experiencing with your console. Thank you for all the information provided regarding your M1400 S/N *****12. Unfortunately, we do not have the schematics for this product because it is discontinued. If you have any questions or concerns, you may call our Technical Support at 1-800-258-6883 when you are in front of the console. Please know that although our support is very knowledgeable and carries a lot of experience, they are not component level bench techs. We apologize for the inconvenience and thank you for choosing Mackie"

Any help would be greatly apprecaited!!!

Thank you and God bless!!!

Robert