speaker capacitors-----leave alone or does it open pandora's box ?

Top end copper foil caps from the likes of Duelund, Jupiter and others have never done anything but improve the sound in dozens of my speaker and electronics upgrades and modifications. Same with Path Audio resistors in my projects. While it is certainly possible that these parts would harm the sound in some piece of gear, I certainly have never heard it.

So I would like to know which hyper expensive caps sound so bright? Perhaps Mundorf Silver or SGO on the wrong tweeter and electronics combo. We listen to complete systems, not just caps. Perhaps Vcap Teflons? But not good film and foils I have used from Jupiter, Duelund, Auydn and Jantzen (Alumen Z).

It is amazing the level on sonic improvement that can be realized with smart cap, inductor and resistor upgrades in speakers. Most builders use run of the mill and “cheap” crossover parts in their $20,000 speakers. They do it to save money. That simple. Yes, one must take into account the sonic goal of the upgrade, the preferences of the listener and the other system components. Match all new parts within 1% and watch Parts that will change resistance.  Smartly done crossover upgrades do wonders for reasonable cost and you can keep your speakers and system in tact without selling or buying gear.   

Erik, as usual you are speaking from experience and I have long valued your speaker posts.  You have a great deal of knowledge born out of your actual building and tweaking experience with speakers.  Thanks for supporting this forum with your knowledge. Much to discover and learn regarding speaker upgrades and it is fun!

It’s more like flipping $12 caps for $150 caps. Jupiter copper foils etc... Flipping $.35 Resistors for $30 resistors. It adds up and after dealer mark up the end price of the speaker is increased substantially. I have performed $2000 crossover upgrades that would increase the price of a $15,000 speaker to $25,000 after dealer mark up etc... The mark-up can be immense on high end gear.

Also, not all designers buy into more expensive parts sound better. They miss opportunities for SQ improvement. Many designers and builders spend time designing and building and have little time or inclination to obcess over how various caps and resistors sound in their design. This tedious task of part rolling and carefully listening is a different body of study and knowledge.

Until and unless you try it for yourself and learn, I’m afraid you will always scratch your head and wonder. Knowledge in this area of audio tweaking takes a great deal of time and effort. No way around it. You have to educate yourself through hours of trial and error with much work and careful listening. It is different from pure design only interested in a part that adheres to spec. Many builders laugh at the notion of “boutique” parts as I have had those conversations. I don’t blame them because these parts can be expensive and they don’t have the time or personality for such tedious and “questionable” endeavors.

At the same time there are plenty of builders that do offer these boutique parts and simply charge for them. They buy into and understand parts make a difference beyond just meeting spec. So it is happening and being offered by builders who know Duelund and Juputer film/paper and foil caps, as well as others, sound better than Poly caps.

Lastly, it is possible to replace a $10 Solen Fast Cap with say a $60 Film & foil cap from Jantzen (Alumen Z) and improve the sound of a given HEA speaker. The speaker set may have 4-8 total caps to replace. Also, you can also improve SQ with $4 Mills MRA resistors over sandcast. The total cost of this moderately priced upgrade is say $400. Some builders after all the mark-ups would sell this upgraded speaker for $2000-$2500 more! This is a very competitive business and one that is hard for the manufacturers to make enough money to stay in business. Every dollar matters and they do watch costs.

I replaced the bottom of the line Solen caps and sandcast resistors in my $14,000 Dali Epicon 6 speakers with $600 worth of part upgrades in the crossover. The result was very pleasing to myself and family. The improvement in sound quality before and after burn in was easily discerned and appreciated. It made a very good set of speakers even more to our liking. The Solen caps sound more closed in and rough compared to the Jupiter film and foils I used. The sandcast resistors also sounded more ragged compared to the more nuanced and refined Path Audio resistors. Dali has a long standing relationship with Solen and they spec their parts. I seriously doubt Dali has listened to their Epicon speakers with the parts I used. They simply used the same approved vendor they have always used. They needed to hit a certain price point and therefore spec’d the part used for these reasons.

Us DIY guys know that nice SQ improvements can be realized with our skills and effort.