# Modding Altec Lansing MX5021 speakers



## RejZoR (Jun 17, 2017)

Ok, I've decided to buy Sound BlasterX AE-5 when it comes out next month and for the sake of upgrading the whole experience, I'm planning to mod my Altec Lansing MX5021 speakers. They served me well for years and since they are one of rare few with wall mount option, I'm gonna buff them instead.

*Specifically these key areas:*
- capacitors in both satelites
- capacitors on the main amplifier
- OP-AMP in the amplifier
- replacement of power converter to more quality toroid transformer (allegedly, this should fix annoying hissing)

I'm planning to replace ALL key capacitors with Nichicon Muse Gold capacitors. For OP-AMP, I was looking at BurrBrown OPA2134PA. It's considered high end and I could get one for price of peanuts. So, I'm even willing to go with something even more high end, I'm just not sure which one is appropriate since I don't know the parameters important for OP-AMPs. For capacitors, voltage and capacitance, no problem. But for OP-AMS, no clue. I also haven't opened up the AMP unit yet, unsure about the complexity of the PCB underneath. Looks fairly simple from above, but I don't know how's it below. I don't have professional solder iron, just very basic clumsy one...

EDIT:
I'm also wondering how to tell orientation of OP-AMPs? I'm assuming it's important how you place them in.

I've also seen some ridiculous Orange OP-AMPs that have tiny PCB sticking out of the plug pins/base. Is that compatible with MX5021 or not? Might be willing to go crazy with OP-AMPs even up to 30€ (the BurrBrown is like 5€ with shipping). Just need to know what to pay attention to when picking them up.


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## R00kie (Jun 17, 2017)

RejZoR said:


> I'm also wondering how to tell orientation of OP-AMPs? I'm assuming it's important how you place them in.


The OP-AMP's have a little notch or a small indentation on the surface that you have to align with the one on the socket:







Same will go for the cylindrical ones, they will have the same markings on the PCB.

Also, when choosing one, make sure to get the ones you need, be it a mono one or a stereo, otherwise, if you pick a mono one for a stereo use, it will either be too quiet or you'll get a difference in volume between the channels.


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## RejZoR (Jun 17, 2017)

Anything else worth paying attention when picking up OP-AMP ? Do they separate in terms of bit depth and frequency range they can work with (or work at)? I'd like to expand the frequency response, although speaker drivers are probably the most limiting factor anyway.


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## R00kie (Jun 17, 2017)

most OP-Amp's operate at very similar frequencies, all they do is just boost the output signal, and colour the sound depending on their characteristics.

The one's that I've used previously were LM4562, and LME49720, the latter being a bit more powerful and neutral, and the former a bit warmer.
And yes, if your speakers aren't good enough, you probably won't notice the difference.


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## RejZoR (Jun 17, 2017)

I'm actually more looking for more detailed sound rather than warmer. But still not too detailed because that often ends up being harsh on the ears.

Any idea on the transformer? I've read somewhere that better toroid transformer supposedly fixed the hissing with MX5021. Just yesterday, I've noticed I can actually tone down hissing noise if I lower treble/bass parameters to zero. Volume knob doesn't seem to affect it, but treble does. Doesn't eliminate it entirely, but lowers it significantly. Some say it's transformer issue, others pre-AMP overdrive. What's your opinion?

Been using it with zero treble and bass amplification, only colorizing audio using Creative Crystalizer and EQ and the sound is... interesting. First few seconds felt like something was missing, but now it kinda sounds really detailed. Probably because treble and bass frequencies don't drive over all other frequencies. I'm assuming.


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## R00kie (Jun 17, 2017)

The hissing you describe is the noise floor of the speaker system you have. I have a similar issue with my amplifier when there's literally no sound coming from the speaker but there's that annoying background hiss. I've been reading about it and people seem to recommending changing the default caps in the amp. But it can also come from the power outlet itself or the cheap cabling on the satellites.


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## RejZoR (Jun 17, 2017)

I've replaced thin satelitte cables with proper high end thick copper wires specifically for speakers. Good thing MX5021 have same cable ports as HiFi systems so it was a snappy replacement. MX5021 is not grounded system afaik. Never had this issue with Creative speakers in the past, essentially used on same wall socket. I do use power surge in front of everything. That should actually help afaik.


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## RejZoR (Jun 19, 2017)

Damn, was checking eBay for cheap OP-AMP sockets and they cost more than OP-AMP itself. Usually in 10 pcs quantity only. A bit annoying.


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## 5DVX0130 (Jun 19, 2017)

RejZoR said:


> Damn, was checking eBay for cheap OP-AMP sockets and they cost more than OP-AMP itself. Usually in 10 pcs quantity only. A bit annoying.


Search DIP8 socket... 
Pages, upon pages, and for less than $1.


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## RejZoR (Jun 19, 2017)

What the frigging hell!? Tried to open one satellite and at first the screw was really hard to move and then its head literally snapped off. I literally can't open it. It's like some idiot glued it together and rammed screws through the glue. Tried two screws and both snapped off. Insane. Why even bother using screws!? Got 3 others out and the last one just got the cross obliterated. Awesome...


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## RejZoR (Jun 19, 2017)

Ok, just ordered all the goodies.

1x BurrBrown OPA2134PA + socket
8x Nichicon Gold capacitors for pretty much everything
2x 4700uF Nichicon Standard Audio (because I couldn't find any 4700uF 50V Gold's that aren't from China. I'm really not in the mood of waiting 1 month for the components. besides, the ones from Europe were actually cheaper in general.

I think it'll be a good upgrade even if it's not the best "Gold" one. Was thinking of replacing some more stuff, but after checking the other side of PCB, I don't think my tools or soldering skills are good enough to replace others, so I'm keeping those stock. I'll already be sweating with the OP-AMP socket with those 8 pins. Pretty crowded with zero margin for error. Transformer is a big ass unit and the number of wires is a bit confusing, so I'm leaving that one out for now. If I could live this long with a bit of hissing, I can do now. Hoping to boost the quality as whole though.

Total cost, roughly 50€ with shipping costs. Seems reasonable considering speakers were around 150€ back in the day iirc.

It's possible it'll make literally no difference or that I'll even ruin them. But hey, it'll be a great learning experience


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## RejZoR (Jun 19, 2017)

Also noticed transformer was totally loosened up and rubber feet on subwoofer moved all the way to the edges of the sub frame XD Nothing double sided TESA tape can't fix


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## RejZoR (Jun 24, 2017)

So, the OP-AMP was first to arrive  Just need socket for it and then I might already start working as components are arriving from different sellers.


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## RejZoR (Jun 26, 2017)

The Nichicon's golden goodness has arrived.  Now I just have to receive the OP-AMP socket and we're starting the project (might actually change caps ahead of OP-AMP and replace that one in the end. The guys were so cool they chucked in 2 extra ELNA Audio capacitors for free as well. Much appreciated


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## R00kie (Jun 26, 2017)

Those are some nice caps there, let us know how it goes.


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## RejZoR (Jun 27, 2017)

Ok, so I've made a first cockup that I just realized as I was about to replace capacitors in the satellites. The capacitors used are non-polar. Genius me bought polar ones. Yay. So, today we're only replacing caps in the amplifier unit...


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## RejZoR (Jun 27, 2017)

Oh wow. Just fired the speakers with just primary capacitors replaced on the amplifier and in all honesty, I was a bit skeptic about the perceivable differences in sound as people describe them after replacing caps. Deep down inside I was expecting no real difference. But this stuff actually does make a difference. I'm still a bit shocked actually. Best way to describe it is "more colorful" sound. Before I had to use special EQ and sometimes even Creative's Crystalizer to really bring sound to life. Now it sounds almost like that without any EQ or Crystalizer. If I turn these two on, the sound almost feels too harsh now. I've also noticed switching Crystalizer or EQ ON/OFF in Sound Blaster Z panel (software setting!) now emits a clicking sound from speakers which wasn't there before. Not sure if that's a good thing or not, but capacitors alone changed that, which is interesting.

Now I actually can't wait to change the OP-AMP and order some bipolar Nichicon Muse capacitors for the satellite speakers. Dis gonna be gud 

A quick photo session of capacitor replacement...

*ORIGINAL CAPACITORS:*



*
NICHICON GOLD CAPACITORS:*


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## Nuckles56 (Jun 27, 2017)

What were the old caps used in it?


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## RejZoR (Jun 27, 2017)

Samxon. A Chinese capacitor maker. Supposedly they are alright, but not for audio applications where Nichicon, ELNA and the likes still dominate the market and are highly praised by audio enthusiasts. As a sheep, I'll just follow the audiophiles flock hehe  And based on my current experience, it's not just a herd effect, capacitors alone do in fact affect the audio reproduction. And I've used identical capacitance, supposedly, if you use higher, they "smooth" out the sound. But I like my audio detailed and it was right choice to go with same capacitance as originals. Voltages are higher, but that doesn't matter much for as long as it's the same or higher.

Old Samxson capacitors are still in good condition (no leaking or swelling) so I'll save them if I'll ever have to fix anything else. They'll be just fine for that.

Lol, just received OP-AMP socket. Plural. 15 pieces. Didn't check order correctly and I've ordered 15 pieces lol. It was just 1 GBP so it's not end of the world. Lots of spares XD Not enough time to replace it now, but I think I'll do it in the evening after work. So excited 

EDIT:
I wonder what are other 4 OP-AMPs for. There is one closest to heatsink which is supposedly the important one which is scheduled for replacement, but what is the other cluster of 3 OP-AMPs for down there next to largest caps (and the one closest to them), they are all of the same make. I'm assuming they are there for subwoofer and satelittes, but I have no clue which is which exactly.

Ok, one of the small "tri" cluster capacitors had a loose solder somehow which wasn't apparent from other side of the circuitry. Resoldered that better and cleaned the contacts around OP-AMP socket, some solder remains could potentially be bridging the gaps between contacts, causing crackling on left channel. Seems to work fine now. Have still replaced that one capacitor back to stock one anyway.

Interestingly enough, either something went bad during whole process, but bass is now a lot weaker with new OP-AMP. New capacitors enhanced it all, but this OP-AMP toned it down. It seems to still work if I crank it up on the speakers bass controls or if I adjust EQ, but without it, not as deep sound. Though, Max Payne piano theme music seems to have just enough bass, so it seems to really depend on music...

I have to admit my heart dropped down in my pants when left channel started crackling, thought I ruined the circuitry. To my luck, I managed to fix it. Wheeeew 

Now, off to (re)ordering caps for the satellites...





After destroying old OP-AMP and installing the socket with new high end OP-AMP I've decided to replace the capacitor as seen on image above. Turns out that was a mistake. I was blissed by absolutely jaw dropping sound for few seconds and then left channel started crackling horribly. Solution? Unplugging the subwoofer speaker from the circuit board. Then both front speakers work fine, I just have no bass. So, next thing tomorrow morning, I'm re-soldering the old capacitor back. I thought I've made an unwanted connection when soldering the OP-AMP socket, but that seems to work just fine as I'm listening to music without sub now for 5 minutes with no crackling.

Not sure what's going on here. Both are polar type, same voltage, except Nichicon has 4.7uF instead of original 1uF. In general that shouldn't be an issue, but in this case, it is somehow. I'm not electrical engineer enough to figure it out. So, returning that part of circuitry back to original state is my best bet here.

EDIT:
God damn, just after posting this, I got harsh interference. Unplugging just to be sure, I'll be fixing this tomorrow. It would suck if I killed the speakers XD


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## RejZoR (Jun 28, 2017)

I think I've kinda inadvertently turned my multimedia speakers into monitor speakers. Before, everything kinda had a lot of treble and bass. Now, high quality music sounds really good, rich and detailed highs, good bass reproduction. Where lower quality or lower production quality music kinda lacks any kind of bass and often sounds either dull or very harsh.


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## R00kie (Jun 28, 2017)

What about the noise floor? Have you managed to lower it?


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## Frick (Jun 28, 2017)

RejZoR said:


> I think I've kinda inadvertently turned my multimedia speakers into monitor speakers. Before, everything kinda had a lot of treble and bass. Now, high quality music sounds really good, rich and detailed highs, good bass reproduction. Where lower quality or lower production quality music kinda lacks any kind of bass and often sounds either dull or very harsh.



You are on the path to enligthenment, grasshopper.


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## biffzinker (Jun 28, 2017)

RejZoR said:


> EDIT:
> I wonder what are other 4 OP-AMPs for. There is one closest to heatsink which is supposedly the important one which is scheduled for replacement, but what is the other cluster of 3 OP-AMPs for down there next to largest caps (and the one closest to them), they are all of the same make. I'm assuming they are there for subwoofer and satelittes, but I have no clue which is which exactly.


This might prove helpful since someone else has already did the same modifications.
http://vc-junk.blogspot.com/2010/08/altec-lansing-mx5021-modification.html


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## RejZoR (Jun 28, 2017)

gdallsk said:


> What about the noise floor? Have you managed to lower it?



Yes and no. I've turned both, treble and bass settings on speakers (both) to zero. Didn't eliminate the background hiss, but has significantly reduced it. To fully eliminate it, I'd have to use a better quality toroid transformer. Only problem is, there are like 8 wires from transformer unit tot he amplifier PCB. If there were just 2 for + and - since I'm assuming it's using DC for circuitry anyway, that would be perfectly doable. But it has like 8 or even 10 contacts and that's just too much for my skill and lack of any kind of serious tools like voltmeter.



Frick said:


> You are on the path to enligthenment, grasshopper.



I have these speakers for so long they already paid themselves back with usage alone. Current investment of about 60€ and getting this out of them is incredibly impressive. I've also ordered 2 pairs of Nichicon Muse Bipolar capacitors for the satellites and then my project will be completed. I'm not going hardcore modifying it totally because I don't have the right equipment (replacing that one OP AMP was a nightmare and I had to destroy the original OP AMP in the process). I want to keep them functional as I've already almost ruined them in the process, but managed to save the day. Not gonna risk it twice.

It does sound nice, although my ears need to readjust a bit to less artificially rich audio. Next step is Sound BlasterX AE-5 when it comes out. It's the reason why I've decided buffing my existing speakers 



biffzinker said:


> This might prove helpful since someone else has already did the same modifications.
> http://vc-junk.blogspot.com/2010/08/altec-lansing-mx5021-modification.html



I've also used these resources:
http://jimmyauw.com/2007/03/15/inside-altec-mx5021/
http://jimmyauw.com/2006/12/15/altec-mx5021-speaker-mod/
https://forum.lowyat.net/topic/1616553/all

Again, I'm going with a middle of the road path, replacing critical components, but not going all out crazy with it. A lot of guys killed their MX5021 in the process and I was also quite close to that. Got a pair of two more capacitors to replace in both satellite speakers and that will conclude my modification. I love these speakers too much to ruin them. Especially because no one makes wall mountable ones anymore so this makes it even more important for me.


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## Ferrum Master (Jun 28, 2017)

TDA7265... I played with them when I was 13 years old and had no money.

HIGH OUTPUT POWER
25 + 25W @ THD =10%, RL = 8Ω, VS = +20V

@ THD =10% ???????? Don't push it more than 15W. It's bonkers... even TDA2030A or more comparable TDA2052... found in ancient TV sets... they were a bit better, build some heavy modded TDA7294, still I disposed how the they worked. You can't turn a integrated turd sounding into something decent, well i was underaged and a bit more stupid and that was it... no more of them... thank you.

Doing all this is... well. Replace the faulty elements, okay that's fine. Don't increase the main filter cap capacity, you will cause high inrush current and the bridge will pop some day. But I wouldn't touch the sound stage.

Sounding brighter? It is a usual sign of RF oscillation... a fake feeling, it went cuckoo after few mins, so you are lucky it didn't explode, those end gainclones like to do that. Also... I really do not recommend changing BJT's OPamps to FET inputs on the blind... why? You saw it there... FETs are faster and more capricious to the surrounding PCB quality. 

Only thing that you could do is actually bypassing the existing coupling caps with some 0.1-0.01uF polymer cap underneath and it would bring you the same results for sure.

Instead of all this money waste... you could omit all that board and replace with something more... mhm... expensive... not 2$ unified end devices driving your precious cones. The result is a different different kind of harmonic distortion peak spectrum, thus the likeness changes... having so much distortion it really changes, without measuring it's quite hard, don't trust your feelings, especially with women and electronics.


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## RejZoR (Jun 29, 2017)

I didn't increase main filter capacitors. They have identical capacitance, only voltage is higher (from 50V to 63V and from 25V to 50V) because I couldn't get any others with those exact capacitance. I'm aware that in general there is no problem using higher voltages and capacitance, but it may sometimes cause problems if you go way too high. Deviating values a bit doesn't harm anything, but going way higher may do so, like replacing original 4700uF with 10.000uF capacitors.

It went nuts because something was wrong on PCB, possibly a solder debris bridging some gap either on OP-AMP or the loose main stage capacitor (that was my mistake since I didn't make sure it' soldered perfectly). This is a DIY project with what I have at home. The solder tool is nowhere near professional, I don't even have OP AMP 8 point de-solder attachment or even basic weave to remove solder. It was all improvised.

As for the sounding "brighter", maybe I didn't use correct words, but describing sound is hard anyway. After replacing main stage capacitors with basically same values, just much better quality and replacing main satellites OP-AMP with way higher quality one, I can really hear more details and sound has changed for the better. I called it "brighter", one could call it "more detailed". I always thought these caps changes are bullshit and they don't change anything, it's just placebo effect because you expect it to change because you used expensive Japanese audio capacitors, you expect it to be better by default. So, my expectations were already zero, but I did it anyway because I was curious about it. But there is a difference and I was legit shocked how it actually changed the quality for the better whether that's good for circuitry life span or not. Plus, it was a nice lesson by working on tight circuitry. So far I've only been replacing components on large empty PCB's using big ass solder tool we used to have. You didn't even have to be precise, they were that empty. I've fixed few things so far with such DIY fixes. One was Creative's soundcard, another one was LCD monitor with swollen and leaking capacitors. This one was not out of necessity, it was out of curiosity. Gotta learn things somewhere. I've spent 50-60€ on more stupid things than this. Way more stupid, so it's fine


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## Ferrum Master (Jun 29, 2017)

RejZoR said:


> I've spent 50-60€ on more stupid things than this.



Holy... not more than 15$... 

You picked OPA2134? Those are one rather dull sounding old chips tbh... gdallsk was right suggesting LM4562/LME49720, they are not perfect, for an general purpose opamp I like them best sonic wise and put them everywhere from now on in my projects, I like them even more than OPA627(not 637 thou, that's not unity gain stable).

Buy a stash of LM4562 for the future... they will soon disappear.

There are few notes on caps... you do not need to put audio caps where shouldn't. Audio caps are a niche product(they kind of promise more linearity in audio spectrum range). Low ESR, general purpose etc you cannot mash them around, it will trigger some unwanted side effects as the capacity isn't the only parameter. Each place where the thing is used has it's use. Often with some good will you do harm ie... that place actually needs a crappy general purpose capacitor. Without measuring the THD curve it is kind of doing things on blind.

Try the coupling method. Put underneath some polypropylene caps underneath it will improve the sonic performance.

Gosh for 60€ you really could put some plain and proper AB class transistor based stage...


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## RejZoR (Jun 29, 2017)

OPA2134PA was like 2€. I did put audio caps only on the audio stages of the circuitry, the rest are stock because I assume those are just raw power delivery and have nothing to do with audio output.


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## Ferrum Master (Jun 29, 2017)

RejZoR said:


> OPA2134PA was like 2€. I did put audio caps only on the audio stages of the circuitry, the rest are stock because I assume those are just raw power delivery and have nothing to do with audio output.



Yeah those are cheap. Also suggest putting caps(1-10uf) under the opamp supply pins to increase their stability. I don't see any of those near the amps, only the two further decoupling caps.

You could take simple nippon chemi or simple nichicons or panasonic... muses in the supply part man... my wallet organ hurts on the sight... and actually they perform a bit worse in the ripple suppression task than the plain supply caps. Well but what's done is done.


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## RejZoR (Jul 9, 2017)

I may have inadvertently introduced slightly more hiss (noise) to the system as Ferrum Master described because of the capacitors replacement. It's essentially at levels I had before with Treble and Bass boosted to 50% on the speakers desktop controller. But the difference in sound makes up for it. I couldn't get rid of the hissing anyway, so why not make it better when it's playing and you can't hear hiss anyway 

Still waiting for the bipolar Muse caps for satellites filtering stage


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## RejZoR (Jul 27, 2017)

Hm, received caps for the satellites an they are freaking tiny compared to original ones. Voltages and capacitance is identical, but these are super small. All bipolar like the original ones. In fact the original 4.7uF one is larger than the new 22uF one. Since I'm a total noob, can anyone enlighten me what's the deal here?


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## RejZoR (Jul 27, 2017)

So, I just decided to replace them despite size differences. This is a filtering stage for high and mid drivers and I'm not exactly sure yet what to think. It certainly changed the sound. I'm just evaluating if it was in a desired way.

Highs don't seem to be as harsh anymore while detail is still there. If I crank the Creative Crystalizer to the max the audio becomes more "vivid" like before, but not harsh anymore which is interesting. The way how bass is delivered from mid drivers also changed a bit. Could observe it also when doing A vs B test with one stock and one modified satellite.

Need further testing with music and games. So far so god though


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## RejZoR (Aug 4, 2017)

Are there any limitations when selecting OP-AMPs? Or can you just stick in any for as long as it's an audio OP-AMP? I've picked the one it was mentioned in the mod log from that guy (even though he fried his Altecs, mine still work ).

For example, if I'd want to go absolutely mad for some reason and stick in Burson V5 Dual in it? I mean, what I'm asking is what factors are involved with OPAMP chips that need to be taken into account. For example, with capacitors, it's capacitance, voltage and polarity (or lack of it). Any such thing with OPAMPs?


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## RejZoR (Sep 7, 2017)

Where could I buy a genuine MUSES 8920 Op-Amp in a DIP8 format? The stuff on eBay makes me question if any of the stuff is even genuine. Especially with the pricing gap from $10-12 for stuff from Japan and Europe to $5 from China/Hong Kong. And with such stuff, it's impossible to even know unless you tear the thing apart and destroy it.

Tried checking the official channels where MUSES 8920 isn't even listed, especially not in DIP8 format. So, now I'm extra confused...


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## biffzinker (Sep 7, 2017)

RejZoR said:


> Where could I buy a genuine MUSES 8920 Op-Amp in a DIP8 format?


Does this help?
https://www.aliexpress.com/item/MUS...-amplifier-MUSES-8920-OP-AMP/32806945257.html


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## RejZoR (Sep 7, 2017)

I could found them on eBay as well. But are they genuine?


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## biffzinker (Sep 7, 2017)

RejZoR said:


> But are they genuine?


They should be for how much they charge. Good question if they are genuine. I was looking yesterday, and comparing to the photo @ http://www.njr.com/MUSES/series/MUSES8920.html
Found a couple places were the amp looked genuine, and going off reviews.


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## RejZoR (Sep 7, 2017)

I've decided to go with eBay, picking the one for $12 and from Japan since the company which makes them is Japanese. It's probably more likely to be original than the one for half the price from China... Or I'll overpay a fake for 2x as much lol

It's a gamble either way, hoping it'll be genuine...


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## RejZoR (Sep 8, 2017)

How do you know the direction of this one since it doesn't have that dip on one end?


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## R00kie (Sep 8, 2017)

it has a dimple, which is the same thing.


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## biffzinker (Sep 8, 2017)

Indented circle on the top?

This might help.


 
http://www.njr.com/semicon/PDF/MUSES8920_E.pdf


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## RejZoR (Sep 8, 2017)

gdallsk said:


> it has a dimple, which is the same thing.



Yeah, I thought that might be it, but I wasn't 100% sure.


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## RejZoR (Sep 21, 2017)

Ordered MUSES 8920 Op-Amp, but there was a mixup and I got the wrong stuff, so now I'm waiting for re-sent item  At least the seller is totally cool so I'll just have to wait a bit longer...


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## Apocalypsee (Sep 25, 2017)

This brings back good memories, when I modding my Klipsch Promedia back in 2007. Everyone calling me n00b back then (not on this forum though) so I done my own research. Some tips for you:

1) Don't swap ALL the opamps, you might make it worse, only change that on the signal path. Simple way is to trace where the input is and go from there.
2) LM4562 and LME49720 are pretty cranky opamps. Check your speaker opamp supply voltage, these opamp tend to sound good up to 15V if I'm not mistaken (max is 17V, too low like majority of soundcard supply 5V they don't sound good either). Also check their temps, if they get hot they might oscillate, a quick dirty way to stabilize them are to bypass their supply to ground via small 0.1uF capacitor, either + or - will do. Still, from my experience, a better design circuit that was build around opamp were miles better than blindly swapping opamps.
3) You better use film capacitor on crossover circuit instead of bipolar electrolytic. They are large but they sounds better.


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## TheHunter (Sep 25, 2017)

I have working woofer and speakers, but busted volume controller (sometimes eq doesn't work). Mine is that version with round speaker

Can sell the whole set  for spare parts if you want ,  45€ sounds ok?
im from lj.


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## RejZoR (Oct 2, 2017)

Finally received high end MUSES 8920 op-amp for the amplifier. It does sound slightly better than Burr Brown I had originally installed.


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## niko084 (Oct 2, 2017)

I'm not familiar with those speakers have you played with adding dampening either CLD or poly fill to the satellites or the woofer? If the woofer is ported you can also play with port lengths. --- You'd want to be careful with shortening (raising tuning frequency) port lengths, making them longer (lowering tuning frequency) is generally safer. Safe being relative to woofer excursion at low frequencies.

Just more ideas for tuning to your liking.


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