EVS Music Purifier

Appears to be a Boucherot cell, a.k.a., Zobel network, which can be used to flatten the impedance curve of a speaker. Ideally, they are designed for the specific speaker drivers and they may already be included in some passive crossovers. If you want to design what is essentially a series resistor and capacitor for your specific speakers, something like this might help. I find it interesting that these are intended to be interchangeably used for low, mid, and high frequency drivers. Here is an interesting review of the Synergistic Research XOT Carbon High-Frequency Transducers discussed in the EVS literature.

These are Zobel networks and they work. I use the Stein Speaker Match with good results. 

Here is what is true......what mitch2 says is 50% correct......in that there are some kinds of Zobel Networks that are used in some speakers after the crossover to flatten the impedance curve of the driver so the xover will see a more linear load.  They use large value capacitors so they operate in the audio domain.

However, mitch2 in incorrect about what mine and Stein Music do....and what the now discontinued Enacom, Merlin, and Walker Audio do.  We use very small values so the high frequency roll off is way above 100K.....these are rf filters.....they have nothing to do with flattening an impedance curve......they are simply filtering the noise coming down the speaker wire.  As to why they work so well, when you cannot hear above 20K?  I don't know....I just want more pure sound.....and this is what they give.  What is really interesting is that every part and wire and damping, etc......that you do in these filters changes the sound.....even if using the same values.  As usual.....EVERYTHING makes a difference.

The $450 Synergistic Research ones appear to suppress rf in a different fashion.....Are they as effective?  Can you use them together with mine?  Someone will play with both and let us know.

Those that trust their hearing will know whether somthing works for them or not.  What others say (including me) is of no importance.....what is real....is what YOU EXPERIENCE.....so far.....people are loving what they hear with my Music Purifiers......if someone does not like what they hear......or they hear nothing.....then they can simply return them for a full refund....including shipping.

I am using Ric’s Music Purifiers on the crossovers for my rebuilt Apogee Duetta Signatures: two pairs on each crossover.

They absolutely make an entirely positive difference (Duettas, Parasound JC1+s, Rossi L2, Silversmith Fideliums, both analog and digital sources).

Here are my specific impressions:

—sound is immediately smoother, volume slightly but noticeably lowered, but dynamics not affected at all

—soundstage opens up quite a bit, width and depth

—what could be  occasionally biting in higher frequencies before is not now

—details emerge from the mix that were buried

—more air

—instruments sound more musical, more like themselves

Overall, the system sounds more like itself. The improvement is immediately noticeable but becomes more evident over time.

I would rate the degree of improvement as roughly the same as a power cord change.

Given that Ric allows returns AND covers postage, I don’t think one could go wrong in trying these. 

I ain't taking them out!

I wonder if putting them at the amplifier end instead of speaker end changes things. Anyone tried that?