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
If anyone is interested in some latest a/b comparison between JRDG Capri and ARC Ref 3, see:
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1200110667&openmine&zzGuidocorona&4&5#Guidocorona
Hi Dave, my suspicion is that the most desirable results may be with 1 PC1 per each 501 monoblock and with Capri on AC. Single PC1 for both amps may not yield optimum headroom, openness, authority. I prefer also larger imaging and ease of Capri without PFC. But I'd be very interested in hearing findings of your friend. Note that my findings of Capri+PC1 changed after the two devices were fully broken in. . . suspect that my initial impression of benefits of coupling were due to brand new equipment. Guido
Guido, have you ended up keeping a PC1 in front of your Capri, or are you still undecided.

A friend has two 501s with a PC1 for each and, after our visit to JRDG last week, he's getting in a Capri. We're thinking that he might be better to drive both 501s with one PC1 and drive the Capri with the other. Of course, the proof will be in the listening, but what would you suspect given your experience so far?

Dave
Hmm, I just thought, maybe Jeff will let me come down on Saturday OR maybe he'll loan Soundins a Criterion for a couple of days and I could listen there, in familiar surroundings.

Dave
Guido, I've been thinking about that, but I'm afraid it'll be hard to fit in any serious listening. I'll speak to our tour guide to see if such a thing will be possible in Jeff's listening room.

Dave
Dave, on the 29th at the Soundings/JRDG tour, try to do some comparative listening of Capri (sans PC1) vs the new Criterion. . . I am so curious to learn if Criterion outperforms Capri and by how much and in which areas. Guido
Really, I have no idea what causes it Guido. Maybe when I'm down at JRDG in the 29th I can ask Jeff. I suspect there's a good reason he puts the power switch on the back and recommends against using it.

Dave
Ahah Dave! I am so glad I am not just 'hearing things'. . . I wander if rapid temporary de-conditioning upon component deactivation is a peculiarity of low temperature components in general, or is it peculiar to JRDG? I do not have enough experience to judge.
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
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
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?
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.
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
I'll be starting the Continuum thread any minute. I just got back from a 3-hour preview of my new baby. I'll take delivery on Friday afternoon.

The first impression, with only 100-hours on the new amp, is simply WOW. If it gets better after a few hundred hours, then it's going to be amazing.

More to come.

Dave
I'm scheduled to go down to the factory on 5/29 with some others to meet Jeff, tour the factory and go over to the shop where the build the chassis. By then I should have me Continuum 500 decently burned in.

I'll write a review when I get the 500 burned in and maybe a little piece about the tour.

Dave
04-16-08: Guidocorona said:
"Excellent Dave, keep us posted. It's almost time to start a dedicated thread on the Continuum 250/500 integrated amps. I am just waiting for JRDG to post some official info on the jeffrowland.com site."

Yes, I'll start a thread after a week or two of burn-in. My only reference is my Conrad Johnson CA200. It's not chopped liver, but I think (hope) I'll be moving into much taller cotton.

Maybe you need to do a review. I'd be surprised if JRDG wouldn't give you a loaner, assuming that the powers that be would allow it. With the Capri, your 312 and the ARC you've got really great references.

Good luck on Jeff updating the site. If it weren't for you, a blurb in a Stereophile blog and Rod I'd never have known about it. However, Rod said that last time he was there Jeff had 30 lined up ready to ship to Japan. He's apparently churning them out with some abandon with plenty of demand from his dealers, even without a bit of advertising from JRDG.

Dave
Excellent Dave, keep us posted. It's almost time to start a dedicated thread on the Continuum 250/500 integrated amps. I am just waiting for JRDG to post some official info on the jeffrowland.com site. In answer to Pinkus, my initial comparative findings for 03/28 on Ref 3 vs. and Capri+PC1 at:
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1205635448&openmine&zzGuidocorona&4&5
still essentially hold. Since then however, the Capri+PC1 combo has opened up further, and I no longer detect excessive pressure in the mid-lower bass. Fellow audiogoner Gshelley heard my system for a brief spell last night. I encourage him to post his impressions -- positive or negative -- of the sound from the Norah Jones CD we played.
Guido,

stop beating around the bush :) Tell us, does the Capri with PFC match up to your ARC REF-3 ?
Dave, when you think that in a Continuum 500 there is inside the rough equivalent of a Capri + 2 501 monos + the equivalent of 2 PC1s. . . G.
Wow, given the Capri's performance and the 501's performance and the PC1+ potential, it seems like a hell of a bargain to have all that rolled together, for not that many dollars more than the old Concerto. I'm thanking my lucky stars that I waited.

You know, I've thought for a long time that it didn't make sense that high-end amp makers didn't include sophisticated power management as part of the package. Why should we have to consider buying an external unit when it's such a big issue in getting ultimate performance.

Dave
Dave, apparently your upcoming Continuum 500 will contain a PFC circuit capable of delivering 1500W at 385V DC of continuous current. By comparison, the external PC1 delivers 750W continuous.
Yeah, I just talked to Rod about my anticipated Continuum 500, expected by month-end. Rod's saying that 1,000 hours is what to really expect for complete burn-in. It'll sound good right off the bat, but improve substantially as it burns in more and more. I'll just leave it on continually and drive the speakers at low levels when no one's around.

Hopefully in May I'll be able to travel down to JRDG in Colorado Springs to see how they put it together.

Dave
Some more data/info trickling in from JRDG. . . estimated break in for Capri as well as for PC1 is at least several hundred (500?) hrs. As Capri draws only 6W, real breakin time for PC1 may actually be longer than 500 hrs. Capri output impedance is 40Ohms. JRDG also estimates that Capri performance is maximized in a fully balanced environment. G.
I have tried two different power chords on PC1 this far:
1. Cardas Golden Reference -- Reasonably extended, but oddly enough, sounding slightly dry, without the low level detail nor the staging I am seeking.
2. Purist Anniversary -- more extended at both ends, with a greater degree of low level detail and sense of space. Also more authoritative than Cardas Golden Ref and with greater harmonic complexity -- some may call this more 'organic'.

This finding is consistent with my experience of the same two PCs directly on the Capri, prior to inserting the PC1 in the chain. This is all together quite curious, because the Capri draws only 6W, yet it appears to benefit from the exceedingly hefty Anniversary.
Please note that I also used the Purist anniversary as my standard chord of choice on the ARC Ref 3, where I prefer it slightly over the Shunyata Helix Anaconda Alpha.

Next, I intend to test the effect of a Shunyata Anaconda Helix Alpha on PC1 and will report results here.
Branimir, you are correct, spoke to JRDG today. 300 series rowland amps implement some form of regulated switching power supply fed by a power factor correction circuit (PFC). In answer to Bill, Continuum 500 also has switched and regulated power supply, but -- if I understood correctly -- its PFC circuit has much greater capacitance than that built into 300 series amps or in external PC1 unit. . . .
04-13-08: Mr_bill
Mr Guido,
Great findings and keep sharing!
Does anyone know if the new Continuum 500 will have analog power supplies for the amps like the 300 series or the switching supplies like the 501's?
Thanks,
Bill

As far as I know new 312 and new version of 301 monos use switching power supplies. They both use PC1 PFC internally.
Hi Tom, I believe the PC1 outputs a static voltage. Capri has an autosense switching power supply. It requires no voltage/frequency adjustment for WW operation. I do not know the internal operating voltage of the Capri. Guido
Guido,

So the device PC1 is outputing 384 volts dc into the Capri? Is this peak voltage or static. Is the Capri self regulating at its input? What is the prime operating voltage of the Capri? Digital power supply I suppose?
Tom
Hi MrB, I am not sure about power supply in Continuum 500. I'll find out and will let you know ASAP. . . . probably in a dedicated thread. . . no worry though, I'll create a link from this one.
Mr Guido,
Great findings and keep sharing!
Does anyone know if the new Continuum 500 will have analog power supplies for the amps like the 300 series or the switching supplies like the 501's?
Thanks,
Bill
TPY, I have heard some of the Linn electronics at RMAF last Fall, although not on the same system where I heard JRDG. I am getting the impression from LINN of a slightly different 'house sound', perhaps a little more forward/leaner than the JRDG gear when driven by PFC. I have heard the 201 and 501 amps in their original configuration: they tend to be on the slightly lean side. I have been told that the PC1 adds a lot of complexity to the output and makes them much closer to the 312. As you may tell, I am avoiding using the word 'better' as much as I can, because that is purely a value judgement. Rather, I prefer to describe what I hear.
I got my Mahlers this past fall and am loving them. I've always used Linn gear for front end and electronics and am wondering if anyone has directly compared to the JRDG stuff with Linn's Klimax amps or the more powerful versions of their Chakra series. My current Linn 2250 sounds very good to me, but of course I'd like to get every last bit of performance out of my Mahlers. I know that JRDG stuff has a great reputation, esp w/ VA speakers; wondering if anyone has ever directly compared it w/ Linn which to my ears is very musical and gets nicely out of the way of the music.
Very interesting Guido. Please keep us posted on your findings.

I am currently breaking in a new Capri that arrived yesterday. I am trying to withold any "critical" listening until the unit has at least a couple of hundred hours on it.

However, at this time I must say I am impressed.