Wilson Audio MAXX resistors


I am about to replace resistors on my MAXX-1 which is in use for the last 10 years. There is no information in the instruction manual and i have absolutely no idea which resistors are to be used for mid/hi freq.. Does anybody have any information on the effect and procedure for resistor replacement/selection.
fpooyandeh
Why do you want to replace them ? They don't wear

I'd recommend these if you just want to try different values

Caddock MP9100

Best of luck

Peter
Contact Jerron or Blake at Wilson Audio.801-377-2233 I just replaced the mid range resistors in my Witt II series. They usually have resistors on hand and will send you the instructions. You basically cut the wires as close to the old resistor as possible loop or carefully twist the wires together and solder them. Use a Weller 140/100 watt solder gun. Home depot has them. The resistors are stamped with the ohm values on them. You can also use an ohm meter on them and if it skips around (mine was 5.3 and the meter would read a lot higher) and you;ll know which one(s) to replace, or the driver won't work will let you know. Put some tape to block any slots or holes in case you drop and solder. Wish I had those Maxx speakers. Best of luck.
Yes, resistors do wear. My midrange drivers did not work. I replaced the resistors, and they are like new.
Polk,

If they do, they are seriously wrongly implemented in the crossover as far as power handling goes. In a properly designed crossover network the resistors should not heat up causing their value to change.

Good Listening

Peter
Polk 432 has the basic information correct and Jerron represents Wilson with class and impeccable knowledge. Was at a dealer in DC when I first heard about the resistor issue. This dealer highly recommended that the resistors be changed and claimed a sonic improvement. Since I have had the good fortune to deal with Jerron in the past, I called and asked about resistors in Wilson speakers.

Being Jerron always gives thoughtful information, his response was generally positive on the idea. I am not sure at this time if Wilson has a policy but I was told that they routinely replace the resistors when speakers come back to them for service etc. Guess the bottom line is that a call to Wilson is most often a pleasant experience and they would be the ones to most directly answer this question. When my WP7 tops were back for a cosmetic issue, the resistors were changed. The sound? Can't tell you of any earth shaking difference but it still made me smile to know they were new. As always, thanks to Wilson for their customer satisfaction and the joy of the music share.
Peter, I was told by Ron Kinear of MusicSystems that they do. New ones fixed mine. As far as them being wrongly implemented, I'm not going to second guess Dave Wilson. I'm just happy that mine work like new.
I'm not going to second guess Peter. He knows a thing or two about speaker and crossover design, and I have not heard of resistor burn out either.
Kkurtis,

I have no argument with that Wilson is a class act, their presentations etc at shows are very impressive, the whole organization comes across very professional. Like wise they build a product with extreme fit / finish.

This of course leads to the question, why implement a part as simple as a resistor that is so under valued as far as power handling that it "wears" out, when there surely are many many choices of resistors that would be powerful enough for the application. Also what does this resistor do to prolonged sound quality does it gradually decline as the resistor "wear" or does it just open up when its service life is expired causing the driver to quit.

From a top quality outfit like Wilson this seems like a sub par engineering choice

Good Listening

Peter
It's nice of them to fix what is apparently a design flaw, but maybe there should have been a recall. Imagine the shipping charges on those systems! It would be more cost effective to send a tech traveling around the country to do the fix on-site.
When the driver(s) fail, just replace the resistors. Just like keeping spare tubes on hand. It's that simple. Either you have the money or skills to be in this hobby...or you don't. I'm simply trying to help out Fpooyandeh fix a problem.
Polk,

In your argument the difference is that a tube do have a finite lifespan, its design dictates that. A resistor properly implemented have a unlimited lifespan it will not wear out, my first post on this subject. To reverse your argument would you expect to replace the output transistors on your SS power amplifier?, probably not.

Good Listening

Peter
Polk432 wrote,

"Probably not is right...I'm above listening to SS."

+1
Polk432,
Why take the issue so personally? You didn't design or build the speakers, and everyone, no matter how gifted, makes a mistake now and then, even Dave Wilson. It's not that big a deal.
I had to replace my resistors. I accidentally turned the volume to high after a few glasses of wine. Sound became muddy and imaging was reduced. I thought I blew my tweeters but it was just the resistors. Changed them and everything snapped back.

Did they say how often you should change the reisistors?
Polk432 and Geoffkait,
Really? What happened to "seperate but equal." It is very sad if we begin to define ourselves, or our worth by the type of amplification devices that we use.
It may or may not be that a design flaw caused the resistor failure, but in the scheme of things, it is not very important, and surely not a reason for hard feelings.
No hard feelings to anyone. I was just trying to help ouit the original person that posted. My mids were not working, so I replaced the resistors, and that fixed the problem. Maybe they also act as fuses so you don't ruin the drivers. Geoffkait plus 1 also.
You think that resistors may act as fuses? Ask Dave Wilson, I'm sure he'll know.
Roxy54...I guess I should have missled the person that wanted help? You seem to have problems that are far deeper than audio. Instead of asking Dave Wilson, maybe you should contact Captain Kangaroo. Peace
No, you gave proper advice. You just became a little thin-skinned when it was suggested that Dave Wilson may have made an error in the design of your speakers.
You think that resistors may act as fuses? Ask Dave Wilson, I'm sure he'll know.

---

I am pretty sure they do.
Grannyring....From Sasha w/p manual.
--
Midrange and Tweeter Resistors
The Midrange Level, which consists of two 3.2 ohm resistors in parallel, and Tweeter Level, which consists of two 1.6 ohm resistors in parallel, resis- tors provide precise level matching for the midrange and tweeter drivers correspondingly. The resistors also act as ultra high quality fuses which open be- fore a driver can be damaged by excess power. See Section 6.0 for details in replacing these resistors in the event one of these resistors is damaged.
Additionally, these resistors can be used to tailor the output of the corresponding driver to overcome tonal balance issues that result from room acoustics.
Bjbcab, thanks for explaining. I tried to tell the naysayers. It's just a different approach, but it is easier and less expensive to replace a resistor than a driver, so NO they are not seriously wrongly implemented. I still wouldn't second guess Dave Wilson.
Just because it is intentional it does not make it sound engineering. Yes there certainly is different approaches, I would never use a resistor as a fuse, and I'm sure David Wilson does not give a hoot about that too :-).

Good Listening

Peter
The design helps to keep from blowing a driver, so that doesn't exactly make it unsound engineering either. Sounds like you may be having a tough time keeping up with the competition.
Polk, no not really.

A resistor used as a fuse, in my mind is just not the right approach. If it is supposed to act like a fuse, and have any effect to that cause it will have to be run so close to its power handling capability that it heats up so much that it almost self destructs. Doing that time and time over will cause it to change in value which will result in a SPL level change form the driver it is attached in front of. There are many other ways to protect a driver in the crossover design.

Think of to this way, you as the end most likely use speaker wires that have been terminated with super fancy connectors, have AWG the size of welding cable. In addition you have painstakingly tightened your connections with a torque wrench etc, all because you want good tight connections with almost no termination resistance. (probably exaggerated but it helps prove the point)

As the manufacturer of the Speaker you go to great length installing binding posts with almost zero termination resistance, using wire of many times greater AWG that actually required or fancy alloys etc, using capacitors of extreme quality, inductors of Oxygen free copper, etc. and then you finish it off with a component that is run so close to its limit that is is on the verge of breaking all the time and will if you run it just a little over limit. To me that does just not make any sense.

Good Listening

Peter

I have no dog in this, um, debate, but as an experienced electronic designer (not for audio), I agree completely with all of Peter's comments just above.

Regards,
-- Al
My speakers have been running just fine since putting in the new resistors. The seller actually paid for them. He may have driven them past their limits the last night that he had them. I never abuse my ears or equipment, so I don't feel that I'll have any problems. I just happen to like the sound of most Wilson speakers and tube systems. Best wishes.
Al,
You beat me to lt, reading this thread with interest and for education as well.
Pbnaudio's explanations and reasoning appear to be undeniably logical based on sensible engineering principles. Why use a resistor in this manner?
Sorry but I have to laugh at some of you guys. Looks to me like the resistor plays a multifaceted role for the Wilson speaker. Read the last sentence in my post. Also, there is a speaker review of the new Alexia where the reviewer found the speaker too laid back, I believe, and changed the resister (through Wilson I'd course).

There are a bunch of ways to skin this cat otherwise we would all have the same speaker and it would be mde by the end user.

Sorry Peter but your statements that this is not sound design makes you look like a chump and a guy desparate to sell his Montana speaker that only the Elk find appealing. Not trying to be mean but as a manufacturer you look self serving.
Bj,

Did you read the entire thread? , I'd recommend starting with the first
post, please do, and then let us know your position on this subject.

And who is the Elk anyway ?

Good Listening

Peter

As an outside observer I find Peter's decorum admirable and he's been very respective of the Wilson product. He has noted an unusual application for a resistor in a speaker and clearly explained he opinion{hardly "chump" behavior}.Yes, there are many ways to skin a cat. There's no reason to aim an insult toward peter{Montana comment} for offering a well reasoned viewpoint.
Bjcab, in terms of "chump" do you have a mirror nearby?
Charles,
Good design approach or not, it's hard to argue with success. No one speaker or component is for everybody.
05-18-14: Bjbcab
Sorry but I have to laugh at some of you guys. Looks to me like the resistor plays a multifaceted role for the Wilson speaker. Read the last sentence in my post ["Additionally, these resistors can be used to tailor the output of the corresponding driver to overcome tonal balance issues that result from room acoustics."]. Also, there is a speaker review of the new Alexia where the reviewer found the speaker too laid back, I believe, and changed the resister (through Wilson I'd course).
That could be easily accomplished, without running the resistors near their limit and using them as fuses, simply by using resistors having the same resistance values but higher power ratings.

That's standard practice when incorporating a resistor (or any other circuit element that dissipates power) into a design. The maximum amount of power it is rated to dissipate (i.e., to be able to handle without getting too hot) is considerably "derated" relative to the maximum amount of power the design is expected to require it to handle.

Regards,
-- Al
First, my apologies to PBNaudio. I was fairly grumpy yesterday and was out of line with my comments towards you.
-----------
So here is my question..... Why have this poor design as some suggest not in one speaker but in the whole line? Also, not just this years model but prior series as well.

I am not an engineer so I am not about to attempt to discuss technical issues but I really doubt Dave just got stupid or careless in this element of his speaker design. I am sure that it has everything to do with sound, flexibility, and technical issues related to the overall speaker design.
Bjbcab,
I believe nearly everyone can relate to the occasionally "grumpy mood" type of day. Keep in mind that no one has questioned Dave Wilson's talent or the obvious success he's earned with his speakers. It's only curiosity regarding an unconventional use of resistors in an audio product.
Charles,
Bj,

Accepted and thanks for "manning up" the net is full of "Keyboard Ninjas" that post utter nonsense and insults, hiding behind a moniker with no consequences.

I don't know why the Wilson team has chosen this approach, which to me and to others here seems questionable, only they can answer that question.

One thought can come to mind, they simply do not want a driver failure. Because of a marketing position they view that a blown resistor is more palatable to their target group than that of a driver failure, even if this solution comes with some sonic degradation happening over time. Before you and Polk get all puffy again, there is no way this does not happen because of the "resistor fuse" heating up over and over again, and eventually failing. If a resistor is used as a fuse it will have to be run too close to its maximum power handling capabilities even when playing moderately loud to have any effect to that cause.

In your example you were cranking it up while zipping wine and the speaker gave up, had the resistor had adequate power handling you would have rocked on and that would have been the end of it. I would not worry about damaging drivers, if they are behind a properly designed crossover they are pretty sturdy.

A high end system from my point of view certainly should be able to be played loud and proud at times without the risk of it shutting down. That being said gross abuse, amplifier oscillation etc, can and will cause driver failure even with the best designed crossovers.

When you are buying a Wilson speaker you are buying more than just a loudspeaker you are buying a status symbol. They more than anyone have been very successful at conveying that message to their potential group of customers. They come in very fancy cabinets, have leather bound manuals etc. All which of course have nothing to do with that actual purpose of the product, which is to make sound, but it certainly enhances the perception of the speaker.

That of course also the reason that you and Polk react the way you did "how dare someone tell me that my loudspeakers are not perfect ! I was told they were"

Good Listening

Peter
I roll speakers like some roll tubes. There are no perfect speakers,( except maybe Montanas?) and I'm not lead into thinking things because someone said so. I'm 60 and retired at 49 due to doing things my way. Be happy and enjoy what you have.
I think I found a way to explain this that is quite easy to understand for everyone:

It is like putting a 80 MPH governor on a Ferrari!

Good Listening

Peter
Maybe on Montanas, but my Wilsons don't sound like they need anything. Glad you rate the Wilsons up there with Ferrari though.
PBN wrote "A high end system from my point of view certainly should be able to be played loud and proud at times without the risk of it shutting down. That being said gross abuse, amplifier oscillation etc, can and will cause driver failure even with the best designed crossovers. "

I agree. I do play loud and proud often but in this instance I was drunk. I had the remote upside down and thought I was turning it down when I was actually turning it up. I pushed well pass any listenable volume. I think I would have blown my tweeters without the resistor failure.

It may indeed be a marketing ploy or just a way to save the customer money when they do something stupid like I did. I think the tweeters are kind of expensive.

I must say that the degradation of the resistor over time from normal use is new to me. In my case it was unintentional abuse.
In regards to Resistors all are not equal.
I have replaced several Xovers and Duelund Graphite Silver
Have been the best ,they vary between 5-10% tolerance.
There is a new exceptional resistor out now hand made in Poland Path Audio . Audio connexion just started carrying these.
These are 1% tolerance ,these are smooth on top but exceptionally detailed and dynamic ?I personally think these are the best currently made.
They even have a 3rd wire a drain to negative for RF,from it's Copper outer jacket. Duelund are still very close a touch more nuetral in absolute terms
But, Path Audio is a bit more 3 dimentional IMO,the Duelund cast are$50 each ,Path are $15 less.Well worth the monies spent.
So much attitude and lack of information here. They are accessible for two reasons; in extreme environments you can adjust the balance to some degree. And yes, they are there for protection as well as equalization in the crossover network. Fuses were determined by Dave to adversely affect the sound and extremely high quality resistors did not. If you don’t want to know there are resistors in your crossover you’d better not look. I have replaced several sets over the years, mainly due to lightning strikes, once for acoustics. I’m getting ready to replace some in a 15 year old pair this week due to a lightning strike. I was a dealer for many years but no longer am. Those who criticize Wilson’s design capability have the right to their opinions. Let me spend some time with one of your designs and I’ll let you know whose opinion I value most...
Hifi,

I agree with the attitude, the ones that feel personally offended if one dares to question a design choice made by the maker of their speaker seem to have it in spades :-)

Anyway, I must clearly question your statement replacing said resistors due to "lightning strikes" are you serious ???  In the rest of the system that the speakers presumably were hooked up to at the time of the "Lightening Strike" there are components way way way more fragile than the above mentioned resistors, did you replace them too ??  Once a lightening strikes anything it usually disintegrates.  That would go for the Amplifiers Preamps etc which are connected to the electrical grid directly - your speakers are not  - they are only connected to the amplifier thats connected to the grid and it would be TOAST.  

So you'll have to come up with a better explanation to why the resistors needed replacing - if you read comments above you may find an answer.

And for the record, I never questioned the value/sound/looks of Wilson Speakers - In fact I think he has done a fantastic job with his company - what I do question is the use of resistors as fuses - electrically it makes  zero  sense.

Good Listening

Peter   


  
Little confusion. Electronics may have fusible/flame proof resistors. Usually these open under 1 watt. Nice to prevent an amplifier failure from cascading and melting the entire thing.

Not practical for a speaker. Actual fuses and self-resetting devices are much more practical, though for homes, honestly should not be used either. More parts to break and age over time. VERY useful for pro speakers.

Properly sized for a speaker’s power handling, a resistor should outlive all of us. Still, if you are going to play, I highly recommend Mills.

Best,

E