View Full Version : Altec Lansing 251 (ACS251) 9 pin mini din pin out

03-01-2011, 03:40 PM
I'm an avid fan of Altec Lansing speakers. My home is set up with various Altec Lansing speakers (Bathroom, Living room, 3 bedrooms, Dining area) connected to various devices and maximizing the DLNA feature of Samsung players.
Knowing this, my cousin handed me down a 2003/2004 Altec Lansing 251 5.1 speaker. I wanted to use this as a mini home theater for my bedroom but the problem is the 9 pin mini din connector from the right satellite to the Subwoofer has been cut and missing. My cousin's dog rip it off and lost it since then (The dog might have swallowed it!).
I was wondering if anyone here had a schematic diagram of the said speakers. At least the pin out configuration.
I've reversed engineered most of the pin outs but I still need the exact connections as I wouldn't want to screw up the ICs by accidentally shorting them through trial and error.
If someone has an extra plug lying around, even with the right satellite it is attached to, please let me know. I'm willing to purchase it and pay for the shipping fees too.


03-01-2011, 06:47 PM
Welcome! :)

Sorry to hear about your speaker malfunction. Hope the dog is going well. Perhaps your friend could check his/her yard or the local dog park to see if s/he can recover the missing connector?

Truth told, the Altec Lansing speakers you're referencing are probably outside of the expertise of those here in terms of knowing the specifics of how they're connected/wired, etc. Long story short, the Altecs that are oft discussed here are vintage items. The company was sold a number of years ago, and changed to a substantially different product line.

Unfortunately, as with many newer portable or computer-related electronics, items like the one you have are not easily serviceable. Even if they can be fixed, the cost is frequently greater than that to replace them. Essentially, they're made to be used and then disposed of when Fido destroys them while working through his abandonment issues.

A quick perusal of the current Altec Lansing site turned up nothing. I don't think they offer tech sheets to the general public, so I'm not sure that the wiring schematic is readily available. Perhaps you could ask them directly:


Best of luck.

03-02-2011, 09:07 AM
Before I started working on the speakers, I did ask Altec Lansing customer support but they told me that my request couldn't be accommodated. So I started on working on reverse engineering the speakers myself. I've been successful in mapping 7 out of 10 pins (9 plus GND), and the last three pins could possibly be the supply, SDA or SCL which is a channel the amplifier and the satellite use to communicate. I might as well study the circuit further before trying a permutation of the 3 wires, that's only 6 orders anyway. 123,132,213,231,312,321.
There has been a lot of people asking how the pin out is but always end up at a dead end. It's time to shed them some light so I'll post more of the results by next week, I ordered a pack of 9 pin mini din from RS components online. They're cheaper at Digikey but costs fortunes to have it shipped to the Philippines.
And since you did mention "Vintage", are we talking about really old speakers? 1950's or so? I hope it wouldn't be a problem to post the results of my project here. Thanks!

03-02-2011, 09:20 AM
Generally, the Altec speakers most folks here are interested in predate home theater or home computer systems - say - before 1985 or so, but some do have much older systems. Those were generally american made speakers and equipment.

The newer companies that use the Altec name bought the name when the original company went out of business and are not the same kind of equipment. Much of the newer gear is not manufactured in the US.

That said, I do wish you the best sorting out the damaged connector.
Ultimately, its all about the music and the fun of listening!

03-02-2011, 11:23 AM
1985, is the year I was born. LOL. Well yeah, most of the speakers I see where either made in Korea, or Taiwan. Unfortunately I didn't get to see older Altec Lansing models except for the JBL drivers my cousin owns, almost half as tall as I am. He's a Bose enthusiast but preferred to keep his largest drivers JBL,. I don't really comprehend why someone would invest a lot of money on Bose systems when there are Altec Lansing speakers that would perform just as good, even better. But my cousin did admit that if the ACS251 didn't get chewed up, he wouldn't have given them to me. For someone with ears sensitive as his , proof enough that the ALs and JBLs have superb engineering and are worth keeping. Just cant wait to receive the mini din connectors and hope to work on them this weekend.

03-02-2011, 08:00 PM
1985, is the year I was born.

Shit. There ends my run as one of the younger members of the community.

Just cant wait to receive the mini din connectors and hope to work on them this weekend.

Hope all works out well for you, and you get them back up and making music! Good luck :)

02-28-2012, 04:48 PM
It's been quite a while. I moved between cities due to work and stumbled upon my speakers last night, and I remember the work I've done last year.I'm glad to say (although it's been very late) that I've reversed engineered the speakers.Studied the data sheet and traced connections and made them work. Sound was still superb. I completed it barely a month after my first post.Been busy with the kids but I suddenly have the urge to create custom housings for the speakers. These are just one set of speakers I cant let go of.

09-30-2013, 07:46 AM
and so? what is the wiring diagram for the 9 pins mini din connector? hoping it is the same diagram as the mx5021...