Wilson WITT (v1) resistors


Hi, I'm new here.

This topic has been adressed many times before, and I've read a lot about it. Still I have some questions, and the answeres would be quite essential to me. I can't find a really proper thread on this forum, so here's a fresh one.

The midrange resistor in one of my WITTs is blown. To prevent another blow, I'd like to replace all resistors. Also I'd like to know how the resistors are wired, and why. And I'd like to know why I blew the resistor.

Wilson Audio wouldn't explain how and why their resistors are wired, but they named three scenarios that could blow their resistor: overdrive (too loud), clipping amp, and using compressed audio files or streaming.

Eliminating overdrive, and bad terminal connection (not mentioned by Wilson), I think clipping or MP3/streaming couldn't hurt a resistor.

A speaker can be damaged by a clipping amp, but a resistor? And streaming or compressed audio: how could that damage anything at all (besides sound quality)?

Wouldn't any resistor wired to a speaker, series or parallel, draw power? Wouldn't an amplifier have to compensate by delivering more power?

My midrange speaker stopped working so the blown resistor may be wired in series to act as a fuse to protect the speaker. The values of 7.9Ω(treble), 6.3Ω(mid), and 15Ω(bass) confuse me though. Wouldn't this result in an amplifier detecting unusually high speaker impedance?

I've read that the fourth resistor (4.2Ω), is for "pahes". This concept is quite new to me. I barely know about phase shift caused by euqualizers. How much power would flow through this "phase" resistor?

I've read about several speaker brands and models that had blown resistors that were actually rated too low, and owners that DIY replaced the speaker manufacturers' choice with different brand/type resistors.

I couldn't find high-power (400w?) bassrange alternatives to replace the Caddocks used by Wilson though, apart from combining A LOT of resistors.

Any reaction on this forum is very welcome. Maybe some day I can be of help on another topic.

- Mike -

omemijk

Showing 3 responses by omemijk

Polk432 replied but I see that content in my mailbox, not here on this forum. Polk432, thanks. Any reply helps. So does yours, by confirming my story for instance, and confirming what I thought to know already. But my post doesn't seem to be complete enough.

 

I know how to replace the resistors. WITT v1s have no access hatch like model II. The heavy-weight resin block with the x-over concealed in it has the resistors' soldering contacts on top of it, so it needs to come out completely, together with the the heavy-weight bakelite bottom panel on which it is mounted. The fragile wires running to the speakers are too short to comfortly handle the x-over, and are VERY in the way when putting stuff together again. It's a two-man job for sure to get to the soldering contacts, and I'd like to fix the problem once and for all.

 

I bought my WITTs used too. To get a complete set of new resistors from Wilson to my place in the Netherlands would cost about 400 dollars/euros. That would be resistors which are common to be blown, from a manufacturer who says they can't handle compressed audio, in a set that is sold elsewhere for about 50 bucks. So I'd like to use different resistors, heavier duty anyway. From the same Caddock product line I can assemble a heavy duty set for abt 160 bucks.

 

In similar configurations audio enthusiasts seem to use inductive-free wirewound resistors to great satisfactory though. Something like bifilar nickel chromium wire, Ayrton-Perry-style wound over a ceramic-aluminium composite core, by manufacturer Mills, but I can only find 12w rated resistors in that product line. Something like 16w AchrOhmiC resistors would be abt the same story. So how could I replace the bass resistors with wirewounds?

 

Even if my WITTs were prefectly serviced for free, at my house, guaranteed to never blow again, I'd still like to learn how and why the resistors are wired, and why it's common to blow them. BTW, due to different mid & low speakers, WITT II resistors have different values: 7.9Ω(treble) / 5.6Ω(mid) / 14.2Ω(bass) / 4.2Ω(phase). I got all resistor values from the Wilson website.

 

Please don't get me wrong. I'm not grumpy over this problem. To me it's an opportunity to learn. Meanwhile I happily listen to another set of speakers.

Buck, thanks. Nice to see this thread is still alive - barely.


I will get it right. I'm looking for a way to create an external fuse box with quickly replaceable resistors. And I'm still looking for the right resistors, and probably some heatsinks too.


Maybe you never blew a resistor and never will, but the WITT II shares the same problem. So, be careful what you wish for. But they do sound nice, so good luck hauling another pair into place.

Some may find this a walk in the park, but I had a lot of trouble replacing the resistors with Jantzen Superes. The Witts now sound horrible with much too much mid. Didn't have time to get it really right, but I will! In the mean time I've explored many other speaker pairs to listen to, some are very nice, but not as nice as the Witts once were. Also, every amp I tried on the Witts became very hot, even amps rated at 2 Ohms. I still have to adress that problem too ...