Engineering perspective


Now meet Herr Strassner, replete with go-ev'rywhere pipe that acts as Sherlock Holmes-style "mental accelerator". Still being relatively fluent in German despite my permanent absence from the father/motherland, I shall casually translate the most vital data of his published technical descriptions. They gave rise to his unique cable networks. Unlike a domestic cable maker who reacted with outrage when wildman Corey Greenberg applied a hacksaw to its plastic boxes and spied with glee on the precious innards, Hans Manfred is proud to openly show you what's inside his.


The HMS tag line "Meßtechnik für Forschung und Industrie" means "data acquisition for research & industry". It hints at Strassner's extracurricular activites. He's been in the industrial sector developing and crafting cutting-edge test gear before he entered cable manufacture in 1993. Strassner candidly admits that when he first looked into the subject of HighEnd audio cables, he couldn't correlate the extent of audible differences with the customary parameters and test values. His belief that "anything sticking out of the ground acts as an antenna" is at the root of his efforts to mitigate MHz alternating current between components that could cause amplifier oscillations regardless of level. If signal propagation exceeds an amplifier's slew rate (and today's HF contamination of celluar phones makes it so), audible distortion occurs.

The following photo shows a circular emitter antenna creating strong RF radiation around Strassner's more affordable Sestetto cable. The scope reading on the cable's outputs shows its relative immunity from such outright assaults.


Propagation speed is another of Strassner's main goals and a direct function of the dielectric constant. Transmissions below the speed of light (which would require a vacuum) suffer HF phase shifts that Strassner feels are clearly audible.


To approach the ideal by about 95%, HMS uses internal Teflon beads that create air inclusion pockets around the interconnects' central conductor while adding structural stability and damping.


Loudspeakers are current transformers while amplifiers act as voltage sources with output impedances approaching zero. Due to low speaker impedance, current flow remains high to develop strong magnetic fields. To ascertain low-loss transfer of the electrical signal, Strassner believes in the importance of controlling said fields.

To that end, proprietary ferrite beads along the outside of the speaker cable lock these energies inside. Strassner claims 0.005% stray-field losses. To optimize the interface between amp and speaker, the 6-pole network boxes can alter resistive and inductive values but also feature a bypass setting. Another HMS exclusive is testing conductor purity for less than 6ppm (parts per million) of ferrous-magnetic particle inclusions. Due to extraneous magnetic field formation, they'd severely impact performance if exceeding said density. The company claims to be the only one even testing for this and that the measurements required to quantify such purity are laborious and expensive.

< An inside look at the network of the Fortissimo speaker cable which slots into the HMS lineup line below the top-ranking Gran Finale MkII.


The manufacturer predicts that 80% of systems will use the bypass setting. It's for the other 20% that the tuning adjustability is designed. On the Gran Finale, the box on the speaker end also includes a HF Zobel network. Conductors are 1,056 oxygen-free copper Litz hairs in a cross-twist.


Similar component matching concerns exist between source/pre and pre/power amps.

Say source output impedance was smaller than 100 ohms, load input impedance 10-47 kOhm. This reduces the load on the source to approach "current limbo". That may not be optimum condition to obtain the best sound from the following amplifier. Hence experimentation with the rotary dials is in order.


The "match box" of the interconnects allows the user, by ear, to dial-in an impedance value that creates a more conducive transition.


With the Energia S/SL power cords, Strassner offers a scheme similar to the loudspeaker cable. A two-pole 3-gang switcher adjusts the values of ferrite and RC filtering. The box also sports built-in hum-countering technology. The power cables are tested for 2,000 amps of surge current and incorporate 3-stage spike protection. In-rush current capability handles up to 50A.


In case my appreciation for Strassner's thoughtful system tuning provisions hasn't telegraphed yet, let me repeat what the Brazilian designer of my AUDIOPAX amps recently had to say in his interview: The audiophile assumption that there's "a best of anything" is lamentably provincial thinking ...


If you could purchase a complete system from one designer... He could then assure that the respective component-to-component interface transitions were optimized. But audiophiles relish the freedom of mix'n'match (quite often to the detriment of results and expense). The engineer intent on offering maximum performance must include some feature of adaptability that accounts for the staggering array of choices his creations might find themselves partnered up with.




Now you'll appreciate my prior caution. In order to perform a comprehensive evaluation of the tuning choices offered with a complete setup of Gran Finale / Energia cables, more than the customary listening sessions would have to take place. Fortunately, I own a micro-power zero-feedback SET, a mid-power zero-feedback SEP, a high-power solid state amp, tube- and solid-state preamps and tube and solid-state CD players. I'm reasonably confident that some wacky combination thereof should catapult me into Strassner's 20% of instances where abandoning the bypass settings would garner audibly superior results.


But I'm not ready yet. Today's merely a teaser - a report on what rewiring my reference system with these Teutonic wires accomplished. All with their default settings engaged, naturally. I wouldn't usually present you with a half-baked review if my stunned excitement over the changes already wrought didn't compel me to. Do you recall that the power cables arrived late? When I removed the NBS power cords from the otherwise already Germanized setup, something very profound happened. Call it synergy. Call it the 100th monkey syndrome of reaching critical mass.


Whatever the reasons -- and I shall subsequently attempt to isolate the contributions of individual cables which will be a mandatory requirement to determine optimal settings for each stage -- whatever prompted the compound effect of using a complete HMS cabling system is presently keeping a bush alight at yours truly's. And this seemed worthy of a "preemptive" action strike on my part. Consider it a post-Mosaic distribution. Similar side effects of drunken bacchanalias around golden idols? As always with cables, that's open to system synergy and listener bias.