Changing resisters in loudspeakers

Along with caps, inductors, and wiring, resisters can influnce greatly on the tonal quality and transprency of a speaker.
With my old Infinity RS3b’s, changing from the cheap stock ceramic wire wound resisters to Duelund graphite resisters in the mids and tweeters are transformative in the transparency of the speakers. You can also change the tonal balance with resisters by using different values.
My Infinity’s, I have to take the bass driver out to do this change, but my Wilson’s makes it easy with removable back panels. The stock resisters in my Wilson’s are very high quality with great transparency, but the sound is a bit forward in the midrange, and bright in the highs in my room even with all the furniture around defusing the sound. So I played with putting more resistance in the mids and highs and finally, like goldilocks would say, it’s just right. The sound now really locks in and is super involving. Thought I just throw this experience out there.
The resisters in the back panels of the Wilson’s.

3 Likes

where do you get such resistors for the Wilson?

Agreed – although my speakers aren’t Wilson-level, I’ve been really happy using Path Audio resistors on my RAAL tweeters. I’ve also heard good things about Mundorf’s top resistors.

I order the resisters from Wilson. They cost about $200 for 4 for the tweeters, and another $200 for the mids, about the same price as the Duelunds from Parts Connexion. The Duelunds I got for my Infinity’s beats the heck out of the Mils I had before and forget about the stock sandcast which is garbage. I heard it all. All these cheap crossover parts really do destroy the sound of a good pair of speakers.

Wilson uses cheap crossover parts?

No, I’m talking about my Infinity’s. Wilson uses the best parts available. I just change the value of the resisters.

1 Like

Which did you change in your 3b? My speakers are IRS Beta which I recapped but did not mess with the inductors or resistors. I did disconnect the breakers.

I changed the caps to Mundorf SilverGoldOil caps, as well as Vcaps. I changed the inductors to Mundorf Copper foil inductors. I changed the variable ajustable resistors to the Duelund Graphite resisters. I rewired the crossover with Cardas cables that I chopped up from a pair of Cardas Golden 5C speaker cables. I added fiber wool stuffing to the cabinet. I replaced the flimsy binding clip on post to Cardas binding post. I took out the circuit breakers. Every crossover parts is point to point wiring hot glued to the back of the cabinet, no circuit boards. Believe me, it’s a completely different sounding speaker after the changes. Beats most speakers costing many times more in realism and transparency.

2 Likes

Thanks!

I’ll look at the inductors and resistors!

1 Like

You’re welcome! BTW, I always wanted a pair of Beta’s, but my room is too small or I would have a pair already. I like the looks of the Beta’s more than the IRS V’s.

1 Like

While some components are demonstrably better, sometimes they are just different (a slightly different flavor) and there is a rather huge confirmation bias with making these changes and sighted listening etc.

The resistors that Wilson uses are placed there as a fuse for the tweeter, which is why the wattage is set where it is.

All the chunkiness and milled aluminum stuff there is a Wilson thing (for bling) but the resistors themselves are pretty nice and used by a lot of companies (including B&W).

They are the caddock thick film resistors and not super expensive for the 1% (like $5-10 in quantity).

4 Likes

Thanks Chris. I’ve blown 2 pairs of Tweeter’s in my Cornwall IV’s and finally decided to add a cheap Automotive 2A fuse in series with the hot terminal of the Tweeter. I’m assuming these Caddock resistors are in series at the output of the high pass filter of the crossover. I’m not thrilled about passing an audio signal through a fuse but at this time, I’m not hearing any ill effects.

I’ll buy a set of the Caddocks and try them out. I will say though if I could afford it, I’d have waited on bought a pair of your FR10’s. I hear the FR20’s at Behr’s place powered by a pair of Ralph’s GaN FET Atmasphere Amps (I’m both a Tubes - Black Ice Audio & GaN FET - Orchard Audio) Fanboy.

I had a the M700’s and M350 and the Orchard Audio Amps stuff just sounded better

For your amusement (feel free to laugh)

.

Well, here is a link to the crossover schematic and picture of the crossover for the Cornwall IV.

Based on this, there is no series resistor in the tweeter network and so you can’t use the approach wilson does. Also, sizing the resistor correctly to blow before the tweeter does is difficult and I don’t know how quickly they blow with peak currents etc. and they did some engineering around this.

A Klipsch horn tweeter plays pretty loud and so should need fuses. Well, as long as you’re happy, that’s what’s important.

If I was going to do a hifi horn system with unrestricted HF dynamics and cohereant sound, I’d maybe look at something like the JBL 4367, JTR speakers, Danley Sound labs (with custom veneered cabient) etc.

3 Likes

Thanks Chris.

I’d contacted Michael Crites who actually posted the schematic you referenced in your response. While he didn’t have the Inductor values. I’d measured the ones in the original Xover with an LCR and sent it back to him for reference. His suggestion was not to go cheap to the Tweeter path but definitely upgrade the BPF and LPF with high quality Caps/Resistors like SoniCaps, Clarity, or in my case (as seen in my post all Mundorf including all air core Copper foil Inductors).

I’m a big fan of Copper foil Inductors for over 30 years when I built my first Homebrews and bought Solo Copper Foil Inductors and Solen Caps for PartsConnexion in Oakville, Ontario.

The sound is fantastic over the original Klipsch Xover.I’ve done A LOT of homebrew Speakers of my own and NEVER blew a Tweeter. Some folks were suspecting there might be DC riding on the signal when I turn on/turn off the Amps. I actually put an oscilloscope at the Speaker terminals and the mild thumps and bumps were negligible (i.e no “straight line” DC visible on scope.

I’d spoke to Klipsch support and offered to send them a custom Orchard Audio module/pwr. supply to test with to see why these Tweeters are frying. Other Orchard customers aren’t having these issue and so I’d even tried my Black Ice Audio Tube Amps which also fried the Tweeters.

Understand that the 1st time this happen was with the factory crossover. The second time was with the upgraded parts (no values were changed).

Thanks for responding,
Joe Goswami

2 Likes