Audio Altec Lansing MX 5021 Modding
- Thread starter cranky
- Start date
Re: MX5021 modding
Didnt work
Moment I turned on, there is this very LOUS KIIIIIIIII sound from left speaker.
Right speaker sound is coming, but that KII sound is present, although much lesser than the left one
Back to sqare one i guess. I just took a small wire piece, shorted the leg to R92.
edit : added pic
Didnt work
Moment I turned on, there is this very LOUS KIIIIIIIII sound from left speaker.
Right speaker sound is coming, but that KII sound is present, although much lesser than the left one
Back to sqare one i guess. I just took a small wire piece, shorted the leg to R92.
edit : added pic
Re: MX5021 modding
You need to
a) trim the excess wire
2) use a component leg rather than wire.
That feedback path needs to be as short and low-impedance as possible. Opamps are very sensitive to any stray interference.
Also I see a short between pin 6 and 7 on that opamp. That may be causing feedback.
Take off the wire link and tell me what you hear - no sound, or sound in one channel only?
You need to
a) trim the excess wire
2) use a component leg rather than wire.
That feedback path needs to be as short and low-impedance as possible. Opamps are very sensitive to any stray interference.
Also I see a short between pin 6 and 7 on that opamp. That may be causing feedback.
Take off the wire link and tell me what you hear - no sound, or sound in one channel only?
Re: MX5021 modding
?? Did it work ?? You have to trim it down to the bare minimum. The input trace runs really close to that resistor. it is a prime candidate for causing feedback.
Edit; Gonna be offline till Thursday. Tomorrow is moving day and I'm not headed back to work till Thursday. Call me if the situation gets out of control. Zhops an Bikey both have my numbers.
?? Did it work ?? You have to trim it down to the bare minimum. The input trace runs really close to that resistor. it is a prime candidate for causing feedback.
Edit; Gonna be offline till Thursday. Tomorrow is moving day and I'm not headed back to work till Thursday. Call me if the situation gets out of control. Zhops an Bikey both have my numbers.
Re: MX5021 modding
Hello all,
Just modded my MX. I have been trying few opamps(5532, OPA2132, OPA2107, THS4032, AD8066) with it.
Initially swapped with some NE5532. There was some improvement in the mids/highs. The sound cleraed up a bit.
Then tried some OPA2132. And the difference was huge. The mids and treble improved a lot. But bass? well was disapointing. It lacked the punch.
Not sure whether it would improve after burn in.
OPA2107: Greater detail compared to OPA2132. Low end also improved compared to OPA2132. Was quite happy with the bass until I tried THS4032 and AD8066. The BB's I tried are no match in the low end to these opamp.
However THS4032 was a bit harsh around 5khz-10khz range I feel.
ANd finally when I tried some AD8066.. oh boy.. The soundstage is just awesome.. I felt as if Metallica is right in front of me giving a show. Very detailed yet not harsh. Ad8066 is my favourite now.
Hello all,
Just modded my MX. I have been trying few opamps(5532, OPA2132, OPA2107, THS4032, AD8066) with it.
Initially swapped with some NE5532. There was some improvement in the mids/highs. The sound cleraed up a bit.
Then tried some OPA2132. And the difference was huge. The mids and treble improved a lot. But bass? well was disapointing. It lacked the punch.
Not sure whether it would improve after burn in.
OPA2107: Greater detail compared to OPA2132. Low end also improved compared to OPA2132. Was quite happy with the bass until I tried THS4032 and AD8066. The BB's I tried are no match in the low end to these opamp.
However THS4032 was a bit harsh around 5khz-10khz range I feel.
ANd finally when I tried some AD8066.. oh boy.. The soundstage is just awesome.. I felt as if Metallica is right in front of me giving a show. Very detailed yet not harsh. Ad8066 is my favourite now.
Re: MX5021 modding
Good for you! I'm surprised you didn't try the LM4562.
The 4032 may be oscillating due to insufficient decoupling and the terrible layout on the MX board.
As long as you're satisfied with your results, it's all good. The satellite and sub amps are well-separated, so opamp-rolling will get you good results in some spots. I felt that the power amp in the MX did not justify a step up to 5 dollar opamps, due to the distortion being too high in the power stages. SO I didn't even try the more expensive LM4562.
I now have a small stock of SOIC adapters (Amarbir stocks those) so I can roll some exotics into regular sockets.
Good for you! I'm surprised you didn't try the LM4562.
The 4032 may be oscillating due to insufficient decoupling and the terrible layout on the MX board.
As long as you're satisfied with your results, it's all good. The satellite and sub amps are well-separated, so opamp-rolling will get you good results in some spots. I felt that the power amp in the MX did not justify a step up to 5 dollar opamps, due to the distortion being too high in the power stages. SO I didn't even try the more expensive LM4562.
I now have a small stock of SOIC adapters (Amarbir stocks those) so I can roll some exotics into regular sockets.
Re: MX5021 modding
After my trials I do think that experiment with some premium opamps is worth it especially when you have it. You will surely feel the difference compared to 5532's.
Presently don't have any 4562 to try. Will surely try once I get them.
Also I forgot to mention that in case of AD8066, I only changed final opamp, near PA's. Rest of them were OPA2107. Just wondering now will there be any further improvements if I changed all through out?
After my trials I do think that experiment with some premium opamps is worth it especially when you have it. You will surely feel the difference compared to 5532's.
Presently don't have any 4562 to try. Will surely try once I get them.
Also I forgot to mention that in case of AD8066, I only changed final opamp, near PA's. Rest of them were OPA2107. Just wondering now will there be any further improvements if I changed all through out?
Re: MX5021 modding
Just 2 words!!!
Thank you Sangram!! :clap:
Mod completed successfully! Replaced 3 opamps to NE5532s (with no damage to tracing on the circuitry!), did the recap (6 Panasonic caps x 22uF + Thermax .47uF x 2) and 2 x Vishay MKPs for bypassing the tweeters.
Thanx a ton to Bikey, Vaibhav and Kichy dada!
Frack the soundstage's improved like shit! Vocals unheard before, tighter and pleasant bass! :jumpy:
Putting up a guide this weekend. Frack the experience was just awesome. Loved every bit of doing it. Brought back those golden memories when I used to do those DIY stuff.
Just 2 words!!!
Thank you Sangram!! :clap:
Mod completed successfully! Replaced 3 opamps to NE5532s (with no damage to tracing on the circuitry!), did the recap (6 Panasonic caps x 22uF + Thermax .47uF x 2) and 2 x Vishay MKPs for bypassing the tweeters.
Thanx a ton to Bikey, Vaibhav and Kichy dada!
Frack the soundstage's improved like shit! Vocals unheard before, tighter and pleasant bass! :jumpy:
Putting up a guide this weekend. Frack the experience was just awesome. Loved every bit of doing it. Brought back those golden memories when I used to do those DIY stuff.
Re: MX5021 modding
I wonder that means, but you sound happy so congratulations You should compare notes with Vandal/he's running my originally modded pair, and those are on 4 years of age now, or a little more.
What's really surprising that I don't really touch the woofer stage much, except maybe the two front end opamps. The 4558s in the 5021 really beat the life out of the music, same with the TL074 on the bottom side. The satellite portion gets the max benefit of the mods, and the clearer mids and top end help the perception of the bottom, as it lifts a bit of muddiness in the overall sound.
I think you have a spare set of components, so you should offer to do it for one more person in Surat. Spread the love
I wonder that means, but you sound happy so congratulations
You should compare notes with Vandal/he's running my originally modded pair, and those are on 4 years of age now, or a little more.What's really surprising that I don't really touch the woofer stage much, except maybe the two front end opamps. The 4558s in the 5021 really beat the life out of the music, same with the TL074 on the bottom side. The satellite portion gets the max benefit of the mods, and the clearer mids and top end help the perception of the bottom, as it lifts a bit of muddiness in the overall sound.
I think you have a spare set of components, so you should offer to do it for one more person in Surat. Spread the love
Re: MX5021 modding
^Yeah thinking of the same. But out of the only 3 TE members in Surat, none uses the MX except me AFAIK. Will put up a thread in the market.
Meanwhile I downloaded the TDA 7265 datasheet from here: http://www.digchip.com/datasheets/download_datasheet.php?id=961292&part-number=TDA7265
Not much greek and latin in there like I predicted. They've given a 2 channel amp circuitry as well. Once I figure out something, I'll shoot u a PM! But seems like the TDA 7265s itself could be interchanged as well? Are the replacements expensive?
Once again Sangram, thanx a ton! Couldn't have been there without your timely help.
^Yeah thinking of the same. But out of the only 3 TE members in Surat, none uses the MX except me AFAIK. Will put up a thread in the market.
Meanwhile I downloaded the TDA 7265 datasheet from here: http://www.digchip.com/datasheets/download_datasheet.php?id=961292&part-number=TDA7265
Not much greek and latin in there like I predicted. They've given a 2 channel amp circuitry as well. Once I figure out something, I'll shoot u a PM! But seems like the TDA 7265s itself could be interchanged as well? Are the replacements expensive?
Once again Sangram, thanx a ton! Couldn't have been there without your timely help.
WingZero
Skilled
Re: MX5021 modding
I can understand . Duh! mine subs wernt functioning properly. Was all thud thud...after 1mnth with rashi finally got speakers back. They said they replaced all internal circuitry. Well the bass is tight now and performance is like a good old mx:hap2: .
Wudbe eager for a mod once i get raws
edit: how much did u spend on the replacements??.
Gunman said:
I can understand
. Duh! mine subs wernt functioning properly. Was all thud thud...after 1mnth with rashi finally got speakers back. They said they replaced all internal circuitry. Well the bass is tight now and performance is like a good old mx:hap2: .Wudbe eager for a mod once i get raws
edit: how much did u spend on the replacements??.
Re: MX5021 modding
^The motherboard and the crossover circuitry of the new MX has undergone some major changes compared to the *expensive* older lot of MXs which retailed like hot cakes at the time!
U'll know why once I put up the guide. Like my previous guide on building HTPCs, this's going to be easy for any n00b.
^The motherboard and the crossover circuitry of the new MX has undergone some major changes compared to the *expensive* older lot of MXs which retailed like hot cakes at the time!
U'll know why once I put up the guide. Like my previous guide on building HTPCs, this's going to be easy for any n00b.
WingZero
Skilled
Re: MX5021 modding
so noob's gonna put up a guide for noobs thts good
I ll be keen on modding once the warranty period get ova.
Gunman said:^The motherboard and the crossover circuitry of the new MX has undergone some major changes compared to the *expensive* older lot of MXs which retailed like hot cakes at the time!
U'll know why once I put up the guide. Like my previous guide on building HTPCs, this's going to be easy for any n00b.
so noob's gonna put up a guide for noobs
thts good I ll be keen on modding once the warranty period get ova.
Re: MX5021 modding
congratulations Gannu ! :hap2:
and try to put up a guide with some pics
looking at your excitement after the modding .. i am thinking of canceling the earlier plan of modding only after warranty period.
anyways first i need to get a decent sound card ..
I guess the sound card is more needed right now then a mod on my MX ?
let me know if you are selling of the remaining components ..i might be interested if the whole mod doesnt cost too much..
how much was the total damage ?
also another problem is i have very very basic knowledge of soldering ..whatever was taught to us ,in the first year ..like basic mounting of components on a PCB,5v dc power supply circuit etc.
so i wouldnt want to take risk with my MX 5021.
would either get some help from some one who's good at tracing circuits and soldering ..
or else my last option would be a local electronic repair guy..whom i dont trust so much ..so that is again ruled out.:ashamed:
congratulations Gannu ! :hap2:
and try to put up a guide with some pics
looking at your excitement after the modding .. i am thinking of canceling the earlier plan of modding only after warranty period.
anyways first i need to get a decent sound card ..
I guess the sound card is more needed right now then a mod on my MX ?
Gunman said:^Yeah thinking of the same. But out of the only 3 TE members in Surat, none uses the MX except me AFAIK. Will put up a thread in the market.
let me know if you are selling of the remaining components ..i might be interested if the whole mod doesnt cost too much..
how much was the total damage ?
also another problem is i have very very basic knowledge of soldering ..whatever was taught to us ,in the first year ..like basic mounting of components on a PCB,5v dc power supply circuit etc.
so i wouldnt want to take risk with my MX 5021.
would either get some help from some one who's good at tracing circuits and soldering ..
or else my last option would be a local electronic repair guy..whom i dont trust so much ..so that is again ruled out.:ashamed: