Posted on Friday, 15th December 2006 by Jimmy Auw
I have chance to mod the Altec MX5021. I think so far MX5021 is one of good candidate to be modded (though I prefer Altec CS21 or 621/641 series, but they have been discontinued).
The target of this mod should fulfill 3 main criterias:
1. Affordable
2. The components should be easy to find
3. Significant result
It’s quite challenging for me, since you know that I don’t (never) expect much from a multimedia based computer (some of them are good, but not good enough for my taste). Anyway, since this is just for fun, so let’s do it.
Here’s the Altec MX5021 system:
This system has a little bit bright sound, metallic, a little bit harsh, not too detail for music, and average mid. I think the subwoofer is for movie (THX Certified) than music. Need to be improved a little bit in the low bass region. I think it’s good enough for most people, but not for me 
The internal crossover uses “bad” non-polar eletrolytic. Also you can find small inductor with ferrite. This is bad. Very bad. They use 1st order for high pass section, F3 at around 8 kHz I think (if I calculate them correctly). The two mid woofer is not working on same region. I think they build a bandpass filter and both woofer works in different region. Need to fire up my simulator to check the actual graphs, but since I think this is just for fun, I don’t sweat a lot 
The components are: 4.7 uF, 6.8 uF, 47 uF, 0.8 mH, and 0.25 mH.
Below is just another view of the stock crossover.
I removed all the “tiny-little-cute” capacitor from the board. Made by Samxon. A well known brand for Capacitor in China, I guess. I’ve seen a lot of electronic consumer product use this brand.
All of the capacitor were upgraded. I used better capacitor for the high pass filter (the black tube). And for the mid-woofer application, I chose the lower grade (yellow tube) than the one used for the high pass filter. Because this is non-elco based capacitor, so you can see the giant size of the new capacitor. Well, I don’t have enough space there. Sorry for bad layout
I’ll do more mods within next few days. I’ve order a special inductor and hope they can make it in small size so I can fit them inside. The cable also will be upgraded to a better one. Especialy the signal cable inside the crossover.
The result so far:
The high extension is absolutely better. I can hear more detail, even from music like Siti Nurhaliza (Cinta Tak Berganti), to Kari Bremens (A Lover in Berlin) and Rim Banna (The Mirror of My Soul). Even my friend (not an audiophile) can hear the different! The mid woofer have not reached my satisfactory level. Cable and capacitor size should be checked again. Will do soon. It’s clear enough that I need a new inductor to fix the mid-woofer. Just hope the ordered inductor can be fitted inside (though it’s crowded enough) or otherwise I need to find a better placement.
The subwoofer also need a little fix. But it should be on my last priority.
Read more:
http://jimmyauw.com/?p=120
Posted in DIY Audio | Comments (44)
December 17th, 2006 at 10:28 am
wew broo… cool abiss… CS21 gua gimana nihhh
mau mod tapi gak ada skill dan knowledgenya 
December 29th, 2006 at 10:58 am
Wow.. mr.. Jimmy u r such a Exellent Craftsman…. Kalo bolehh bantuin wa mod MX gwa juga donk…pretty please…
coz im totally amateur in Electrical Device& component:(
January 4th, 2007 at 11:20 pm
wow, that was quite an awesome mod.
maybe you can help me and jozzy do a little works on our speakers?
March 15th, 2007 at 11:54 am
[...] If you haven’t read my previous article, please click here. I discussed the mod of MX5021’s satellites. Now, it’s time for the electronic parts I opened the Altec MX5021 subwoofer yesterday. Here’s the picture of the board inside. We can see two big rectifier, some big capacitors (removed from the board), and some op-amps (all are ST4558C). [...]
April 19th, 2007 at 12:06 pm
Bro Jimmy, saya punya MX 5021 + SC Audigy2 kalau mau ningkatin kualitas suaranya secara software (driver + player) pake apa? Oya, kalo tetang Mod MX 5021 ini sptnya teknis banget ya… dan saya juga binggung mau beli kapasitor buat upgrade nya dimana? dan bisa ga dikerjain sama teknisi service an audio, krn saya ga ngerti tuh elektronika takutnya malah rusak kalo upgrade sendiri, mohon bantuannya bro jimmy, thx
October 7th, 2007 at 1:46 am
[...] there was just one Jimmy Auw in Indonesia or someplace who had done the mods. That webpage is here: Jimmy’s Junkyard » Blog Archive » Altec MX5021 Speaker Mod I don’t agree with all of Jimmy’s mods, and down in the comments section are what I ended up [...]
November 20th, 2007 at 7:12 pm
What are those huge capacitors made of? Polypropylene?
January 16th, 2008 at 12:34 am
Jim,
pls tell me the replacement components’ voltage and the uf…
January 16th, 2008 at 3:39 pm
Same value as original.
Thank you.
January 16th, 2008 at 5:13 pm
bro.. dari forum banyak anak2 tuh pingin modifikasi Altec Lansing MX5021, termasuk gw bro.. gimana kalau kita upgrade bareng2… gw yakin semua pasti pada mau.. tar saya yg atur soal pertemuan. tar bung Jimmy tinggak datang dan hasil apa yg kita kerjain bisa kita masukin ke forum sebagai bahan diskusi. dimana dengan speaker yg sudah ada kita tingkatkan kualitasnya.. tapi, bung Jimmy sibuk sih.. and gw ngerti lah…
January 16th, 2008 at 6:13 pm
Memang ada rencana ketemu di mana bro? Dari saya pribadi agak susah dari sisi komponen karena komponen rata2 stok lama saya…. barang baru gak tau ada atau tidak… kalo memang ada, rasanya saya bisa bantu untuk sekedar kasih panduan (jikalau memang pas waktunya cocok dan saya tidak janji)…
Coba kontak dengan bro Pemula_Kompie juga di CHIP Forum… dia juga suka mod…
Thanks.
January 17th, 2008 at 9:49 pm
Thanks for fast reply
I had opened the satelite last night, but it’s a cut-cost product from AL, darn… (pls refer to the link below)
Just got 1 cap on the board, 50v 15uf for tweeter.
should i replace it with a bypass cap?
http://img33.picoodle.com/img/img33/4/1/15/skydriver/f_q03m_4e1a216.jpg
January 18th, 2008 at 9:18 am
Replace it with better caps first if you can… changing XO design is not recommended unless you know what you are doing…
January 19th, 2008 at 5:45 pm
done.
Replaced the 50v 4.7uf with 100v 4.7uf bypass cap and changed the cable too (inside the satelite)…
anyway, cant found 100v 15uf cap to replace the 50v 15uf and i just leave it =.=”
thanks!
April 10th, 2008 at 5:41 pm
setelah dari article mod subwoofer
koq modifikasi satelit kayanya beda sekali dengan subwoofer
1. komponen2 kuning dan hitam itu apa tergolong kapasitor?mereknya? soalnya bentuknya beda
2. tinggal ganti dengan komponen yang value-nya sama yha?
3. kabel2 yang warna warni itu perlu diganti juga? klo iya ada saran untuk jenis kabel yang harus dipakai?
April 25th, 2008 at 11:12 am
hi there jimmy,
i’ve open up my speaker and its nothing like ur crossover cct, urs are 3-way crossover cct but mine only 2-way crossover cct. i think my spk was one of the cut cost version (sad) anyway can u send me the crossover cct 4 ur speaker, i would like to change the crosover of my spker to see da diffrence, thnx.
April 27th, 2008 at 7:55 pm
You can’t use different crossover design. Most likely, Altec has changed the drivers for your speaker, so they came up with new crossover.
Better stick with the one that you have.
Thank you.
April 29th, 2008 at 7:05 pm
i just want to try out how different the sound would be with 3-way crossover, i notice that they are stil using the same speaker but only change the crossover design to 2-way to save the build cost on the components used . i dont know what they did have an effect on the THX certification. maybe this can help afew out there whose not satisfied with the newer model sounds.
May 10th, 2008 at 11:09 am
Bang Jim, aku udah putus asa nih nyari MX 5021, kalau udah bosan boleh dong kita beli bang, posisi kita di medan, gimana kira2 bang?
May 11th, 2008 at 5:38 am
@Yance cari speaker seri lain aja bwt di modif…. kan lebih asyik …rencana mau coba modif ACS 45.1
(white n black series) … blm ada wktu nh…pgn bgt…
June 28th, 2008 at 3:42 am
Please help me with the modding of this AMP http://my-cool-gsm.hit.bg/DSC00097.JPG
I wont to clear the sound.PLEASE HELP ME!!!
Sorry for my bad English.
July 8th, 2008 at 5:04 pm
Hi Jimmy,
Nice article!
> Jimmy Auw Says: April 27th, 2008 at 7:55 pm
> You can’t use different crossover design. Most likely, Altec has changed the drivers for your
> speaker, so they came up with new crossover.
> Better stick with the one that you have.
From what I can see on your photos and on this one http://img33.picoodle.com/img/img33/4/1/15/skydriver/f_q03m_4e1a216.jpg , I would say they are still the same 4-ohm drivers, according to type numbers. I think the “performance optimization” process took place here making the product cheaper to build with “quality still acceptable for consumer”.
Could you, please, post a photo of the back side of satellite crossover PCB (if not the schematics)? At least it would be interesting to see what Altec’s engineers came with prior to the marketing department intervence
Regards,
JT
July 8th, 2008 at 6:14 pm
Hi,
I dont have the speaker on hand now.
Please be noted that same 4 Ohm speaker doesnt mean it’s the same one. We are not talking about impedance only, but also the T/S parameter. Different T/S parameters need different crossover design. We cant make sure they are the same or not unless we do the measurement for T/S parameters.
Thank you.
August 5th, 2008 at 9:36 pm
can you help me how to mod my altec 5021.
December 9th, 2008 at 12:01 pm
om…jimmy…ur my favorit for electronik man….
bs tolong di sebutin yg lengkap komponen2 yg diupgrade… aq gak tau itu apaan contohny yg kuning besar itu…
misal nie om…
1.kapasitor merk apa brp farad brp volt
2.dst…
gt lho om… makasih ya… smoga ditanggepin…
kalo bs jg dikasih tau kapasitor ini sebaikny diganti dgn yg ini…
pm diimel saya ya om….
oh ya, kalo kabel standart dr sub ke speaker tu di upgrade ngaruh besar gak dr yg standart?… ngaruhny apa?…
December 9th, 2008 at 10:27 pm
Hi,
Basically ganti dengan nilai yang sama aja.
Kapasitor kuning itu murahan, merek Audiophiler. Cari di Glodok aja.
Yang lain-lain juga modal cari di Glodok aja. Gak ada barang2 mahal koq. La wong speaker murah, jadi upgradenya jangan sampe seharga speakernya. Kurang lebih abis 300ribuan aja koq waktu itu.
Kabel speaker ngaruh bro… cukup banyak di kualitas suaranya.
Thanks.
December 10th, 2008 at 12:23 am
wah makasih banyak om jimmy…
kayany glodok kejauhan dech… saya kan tinggal dimalang… deketny jg surabaya…
oke dech… jadi pointny ganti nilai yg sama…
bagi saya sie nie speaker lumayan mahal (1,9jt)… kalo om jimmy kan duitny banyak hiks..hiks..
ya dech saya coba dulu… kalo ada trouble ntar saya ask lg dech…
thanks alot…
oh ya… sepertiny kabel yg rada mahal ketimbang komponen… kmrn saya tny ditoko hifi… tp lupa merkny… semeterny 45rb rencana mo saya panjangin kira2 ada saran kabel apa gak om?… yg lumayan murah dan lossny dikit…
December 10th, 2008 at 9:03 pm
Kabel saya aja pake Canare yang dulu beli cuman Rp 5000 semeter.
Hampir semua barang saya murah2 semua bro… dan rakitan pula. Kalo duit saya banyak sih mending beli jadi kali ye? :p lebih keren…
Thanks.
December 11th, 2008 at 12:18 am
thanx alot om… makasih infony… ntar q cari Canare dech…
wah… makany aq ya mikir2 beli kabel 1 meter 45rb… mana msh kul lagi…
kalo kabel dr satellite ke sub itu diganti jg gak ya?… kalo diganti apa jg ganti dgn canare?… rencanany mau q panjangin 5 meter mau ditaruh diatas…
oh ya om… cm sekedar info… kan gw jg suka audiophile… kalo om susah cari2 yg rare… contohny xrcd ato piringan hitam… bisa liat di avaxhome.ws browse aja audiophile ato apalah yg om suka… tp gw sih nyaranin donlot yg pnyny aksman(browse aja aksman) dia beli piringan hitam trus dishare… (tp gw gak nyaranin lho om, kan i*egal)… tp kalo cm sekedar buat dengerin halal koq… hehehe…
December 19th, 2008 at 9:53 am
Klo tuh caps diganti ama yg kelasnya solen, gak worth ya om jimmy.
December 19th, 2008 at 10:25 pm
Kalo menurut saya sih yang penting2 aja diganti yang bagus… Yang kurang penting sebaiknya tidak perlu… sayang duitnya…
Thanks.
December 21st, 2008 at 5:52 am
Iya, maunya Crossover giganti solen, caps power diganti elna for audio. Ama opamp.
Nah kira2 klo crossover yg diganti pake solen, worth gak. Atau cukup pake caps film biasa ?
Trims.
December 21st, 2008 at 11:10 am
Pake Solen untuk yang high pass tweeter aja. Saya juga pake Solen hanya di posisi ini.
Thanks.
December 22nd, 2008 at 4:40 pm
jadi untuk tweeter aja pake solen. mid pake caps film biasa ya. Makasih sharenya om Jimmy.
December 22nd, 2008 at 10:54 pm
Sip… Silakan dicoba bro.
Thanks.
January 27th, 2009 at 8:06 pm
Hi;
One of the pins has broken on the DIN controller of the Altec Lansing MX.5021.The support provided by Lansing has not been good!
Please could you send me a wiring diagram for the 9 pin plug of this controller.
Many Thanks.
Best Wishes.
Pete Frizzel
January 28th, 2009 at 12:29 am
Hi,
Sorry I dont have any wiring diagram.
Thanks.
March 10th, 2009 at 5:06 am
Hi,
)
Jimmy, (or some one else) could you post, please, a picture from the back side of satellite crossover (if it will be the scheme, I would be twice happier
Thank you in advance.
April 23rd, 2009 at 8:35 am
Sorry Mr. Jimmy Auw I’ve forgot to fill the name.
Gwa ulang lagi jawabannya
Jimmy Auw berkata :
Kapasitor kuning itu murahan, merek A**********.
kenapa pakai kapasitor yang murahan? kenapa ngga pakai kapasitor yang murah tapi bagus?
induktor yang bagus itu dari bahan apa? mohon bisa disebutkan dari yang bagus sampai yang murah tapi tidak MURAHAN?
thx
April 23rd, 2009 at 9:11 am
Hi,
Kapasitor “murahan” di kelas segitu (dan gampang diperoleh secara massal) ya memang yang kuning Audiophiler itu saja… tidak ada pilihan lain yang lebih bagus dari sisi cost/performance (kalo Anda nemu, boleh share di sini). Mau pake yang lebih “mahal” ya banyak saja, tapi apa iya speaker MM kelas begini mau habiskan ratusan ribu untuk kapasitor. Tentu tidak, bukan?
Saya sengaja highlight kata “murahan” supaya orang yang baca itu tidak menganggap mod ini menghabiskan uang banyak. Dan semua parts bisa gampang diperoleh di toko elektronik macam Glodok ataupun toko2 yang jual produk speaker/audio.
Silakan kalo mau upgrade dengan yang lebih “mahalan”
Perlu diingat juga, “murahan” tidak identik dengan jelek. Saya juga ada beberapa capacitor lama yang bersuara bagus dan murah, tapi umumnya barang NOS dan nyarinya susah. Makanya saya tidak sarankan untuk mod “massal” disini.
Induktor tergantung selera, ada yang suka solid core, hepta litz, sampai foil. Makin atas grade-nya tentu makin mahal. Jenis yang sama dengan beda produsen pun harganya beda (contoh foil dari Alpha Core vs Duelund). Mau yang “murahan” bisa gulung sendiri (atau hitung dan minta tukang trafo gulungin). Yang “murahan” gini suara belum tentu jelek, tapi secara penampilan dan kalo orang liat, pasti disebutnya “murahan” (lah iya karena harganya murah tho?).
Thanks.
April 24th, 2009 at 5:58 pm
Thanks for your reply Mr. Jimmy
Yang Mr. Jimmy maksud dari murahan itu adalah harganya yang murah, dikira jelek, sorry for misunderstood you.
April 24th, 2009 at 6:20 pm
No problem
Thanks.
May 13th, 2009 at 7:23 pm
Hi everyone,
I have spend sometime modifying Altec MX5021, well, the sound were much better than initial one (thanks to Jimmy). But this quality didn’t satisfy my ears, (if someone made computations for the second modification of speakers (the one which has first order high-pass and second order low-pass filters) he saw that the range 1.5…8 kHz is simply canceled). Well, guys, two month ago I’ve bought real stereo system (two speakers Q-Acoustics and Pioneer amplifier), compare to which Altec is the generator of noise.Of course only speakers costs ~20% higher then all Altec MX5021 system, but difference is like between Ferrari and Fiat, it’s not important how you will tune the Fiat, it could be better or worse, but it will never become Ferari…
All the best.
June 21st, 2009 at 4:57 am
To remove the hiss I replaced the transformer inside for a toroidal one, and now I have them hiss free!:D