2. amps-preamps
  3. 1208046462

Rowland PC1 PFC on Capri pre early findings

I have just re-inserted a Rowland PC1 Power Factor Correction (PFC) device in my system 1 hour ago. It is feeding a Rowland Capri preamplifier. Previously Capri was powered directly by a Purist Anniversary PC plugged into an AC wall outlet. Now the Purist is powering the PC1, while the Capri is being fed 384V Direct Current (DC) by the PC1 through a small Rowland supplied pigtail looking somewhat non-denominational. The PC1 is designed to increase the operating efficiency of the device that it is applied to and to eliminate capacitor charge ripples caused by AC. It was deliberately designed for high current Rowland, and not for the Capri pre, although the Capri is compatible with it without any changes of jumpers etc. . .; this means that what I am doing here is purely an experiment limited in scope to the Capri.

I have been playing only 1 CD on repeat this far: Nora Jones 1st CD, so my findings are just very early surfacy impressions. PC1 seems to have extended the frequency range top to bottom; bass appears to be further defined with greater authority/punchiness/control; imaging appears to have acquired enhanced focus. . . this means that Jones's head actually seems more contained, centered, and perhaps slightly smaller than before; instruments are more localized in the 3 dymensions; stage is wider/deeper; there are more harmonic 'bristles' or texture and a more evident leading edge in small transients from percussion instruments. I am perhaps perceiving a very slight increase in sybilants and a slightly more forward presentation. . . but the PC1 is not at all broken in. I will document further observations as the PC1 breaks in and I play other CDs.

One more potential variable is the Rowland-supply power pigtail to the effect of the PC1 on the Capri. Would an upgraded DC pigtail have any audible effect?

For your info, The PC1 can be applied readily to the Rowland Continuum 250 and Capri without any setup changes because these devices have autosense multivoltage power supplies. the 102, 201 and 501 amps require some alteration in fuse setup. The Concerto products require both a fuse setup change and a change to internal jumpers. PC1 is not applicable to JRDG 300 series amps nor to the JRDG Continuum 500 integrated, because these devices already incorporate PFC circuitry. Note that the PC1 is NOT a general purpose power conditioner and is not compatible to any arbitrary device/brand. I have no information about applicability of PC1 to older Rowland amps. It is likely not compatible with amps and pres from other manufacturers . . . so do not try wild experiments with the PC1 without consulting and approval from your dealer, JRDG and the manufacturer of your amp/pre. The PC1 retails for $1500. It is available from Rowland dealers like Soundings HiFi of Denver (Co) (303) 759-5505.

The rest of my currently active configuration consists of: Teac Esoteric X-01 Limited, Rowland 312, Vienna Mahler v1.5 speakers. Capri+PC1 is currently in use instead of my ARC Ref 3.
guidocorona
guidocorona OP
4,298 posts
 
Hi Bob, yes I have some new findings. . . and they are still trickling in. . . I have now tried 3 different PCs on the PC1+Capri combo: Cardas Golden Ref, Purist Anniversary, and Shunyata Helix Anaconda Alpha. I am slightly surprised about my own findings. . .
See today's post on the following thread:
http://forum.audiogon.com/cgi-bin/fr.pl?fcabl&1210544776&openmine&zzGuidocorona&4&5#Guidocorona
guidocorona OP
4,298 posts
 
I have just learned of a few instances of audiophiles and dealers blowing fuses and frying components because they connected a PC1 without reading the instruction card. Only JRDG devices having autosense power supplies and having no Power Factor Correction built in can be connected to a PC1 without some prior reconfiguration -- these devices are the Capri and the 102 stereo amp only. All other JRDG components running at less than 220V 50Hz require some external or internal reconfiguration, or are otherwise incompatible. Non JRDG components are incompatible by definition. Unless you enjoy impromptu/costly flash bang shows, read the PC1 instruction card and consult your dealer before 'tis too late.
sflazor
16 posts
 
Guidocorona--Do you prefer your Capri/PC1 to your Ref 3? If someone were considering these two preamps for use with a Jeff Rowland Model 10, what would be your recommendation regarding which to purchase?
guidocorona OP
4,298 posts
 
Hi Sflazor, you will find some of my preliminary findings toward the top of this thread. . . . however I am still evaluating and do not have a definitive answer yet.

Still doing some listening and will keep everyone updated. For one thing, both Capri and PC1 in my system should be now completely burned in with well over 500 hrs on each. I removed the PC1 yesterday and fed the Capri directly through my Anaconda Helix Alpha. System remained turned off for about 10 mins. After restarting system was initially hashy, and took at least 2 hrs to restabilize. By the end of the evening it seemed to me that without PC1 on Capri imaging was larger, macro and micro dynamics was increased and so was harmonic density. . . I thought I heard more rozin noise from cello bow on strings. Capri with PC1 is likely sweeter, but is possibly less extended and bass may be little fuzzier by comparison. There are some indication that without PC1 some overly bright recording may sound. . . well, rather bright. Note that I started using PC1 on Capri when both were almost completely new out of the factory. . . . a possible explanation for my recent findings at odds with older impressions? It is also worth pointing out that JRDG is not necessarily recommending PC1 for Capri. . . PC1 was designed for high current applications and Capri draws only 6W. . . . what I have been doing is a very personal experiment indeed.

I will now play capri in this configuration for a while, then try the Ref 3 again and will post updated impressions. Guido
dcstep
1,518 posts
 
My experience with changing PCs and ICs on my Continuum 500 is similar to Guido's. You can't really do efficient A-B comparison because the amp really needs a couple of hours to "recharge" any time it's turned off. Of course, I can mute it to change ICs, but I tried swapping ICs while I had the PC out to make a swap (don't get excited Guido, I was just swapping the stock cable for the CST-PC).

Most people wouldn't consider the just-turned-on sound horrible, but you don't want to be reviewing components in that condition. It's just not at its best. So now, if I change anything, I don't even try listening for two hours.

OTOH, since it's left on all the time, I really like getting up on Saturday mornings and having it really sing from the very first cut.

Dave
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