Pre-amp for Rowland Model 102

I'm using Power Factor correcting conditioner Furman Elite 20 PFi with Rowland 102. It does not affect dynamics but makes everything cleaner. The strange thing is that bass became cleaner - more even and musical. Very good non-sacrificial over/under voltage protection is another benefit. I don't have to worry about leaving it ON 24/7. 102 is plugged into high current outlets while Benchmark DAC1, I use as pre, is plugged into lower current preamp dedicated outlets.

Hi Kijanki, fascinating info. I did not know that Furman was producing a PFC-based conditioner. how has the Furman Elite afected harmonic detail, microdynamics, and mid-treble intermodulation? Can you isolate the separate impact on M102 and Capri? Guido

Guido, I don't have Capri. Furman made it cleaner. They claim large peak current available (large capacitor behind large inductor) but it did not improve dynamics (other than removing bass resonances). Furman made big difference on my previous digital (DLP) TV, making colors more clean and saturated. I know it doesn't sound plausible in digital domain but removing jitter can do it. One thing that made huge difference was speaker cable (Acoustic Zen Satori) that enhanced lower midrange (Cello, male voice chestiness etc.) where 102 seemed to be a little thin. In addition it has this "silky" quality (but I'm rather new to high end cables).

Guidocorona,

"It bested my ARC REF 3 in harmonic development, control of treble intermodulation in complex passages (think of multipart violins)"

In reference to your quote above, how do you define harmonic development and treble IM? Are they something you listen for or measure?

ZD, I only "measure" things with my ears, thus I apologize in advance for the unscientific and somewhat subjective nature of the following....

On the subject of treble intermodulation.... Frequently, on multipart string music, you may notice that there is a range of chorded notes, approximately in the 3rd treble octave, that have the habit of sounding rather harsh, distorted, and metallic. What I always look for is ways to make those notes sound like "music", without resorting to filtering effects.

On the subject of harmonic development.... if you listen carefully to piano music for example, you may hear the fundamental frequency, but also a set of harmonic frequencies that rise, sustain, and decay on their own terms.... this complex and evolving harmonic resonance is what gives an instrument some of its individual richness, or.... palpability.

My experience is that a PFC-based DC front end for an autoranging SMPS can increase an amplifier's ability to expose the complex behavior of independently decaying harmonics, and control a fair amount of treble harshness, without ever being perceived as a band-pass filter.

For example, integrated PFC rectification is one of the main differences between the class-D Rowland M501 monoblocks and the class-D M312 stereo.... Yes I know, there are other factors involved, such as higher quality transformer coupling etc... but.... M501 is a fun amp with a lot of power that sounds a little "matter of fact", while M312 sounds much more musical and emotional.... M312 Was my very favorite power amp prior to my adoption of the Rowland M725 monos, which while being based on class A/B design, are still fed by a PFC-based DC front end. Back to M501, the monoblocks can be front ended by a PC-1 PFC-based rectifier on each... Owners that have used M501 in such configuration claim that they rival the overall musicality of M312.

Warning, unlike Furman Elite, PC-1 transforms 120V AC into a 220V DC current... So do not feed it into any device unless the target component has an autoranging power supply, or it has been switched to 240V operations, lest.... you will be regaled by a cute puff of blue smoke and a slagged component.

Guido