Phono Pream­Pli­fier

Australian HIFI - - CONTENTS -

Not fancy on the out­side, but pretty fancy in­side, and its sound is breath­tak­ingly beau­ti­ful!

Maybe Para­sound should pro­vide ‘Work in Progress’ signs with its JC 3 phono pream­pli­fier, be­cause it’s def­i­nitely a work in progress, with both Para­sound’s owner, Richard Schram and his de­signer, John Curl, now on the third it­er­a­tion, with both ap­par­ently un­will­ing to jet­ti­son the orig­i­nal ‘JC 3’ model num­ber. So in the be­gin­ning there was the JC3, which be­gat the JC 3+, which be­gat the JC 3 Jnr. How­ever, the JC3 is no more, leav­ing only the JC 3+ and the JC 3 Jnr ex­tant.

I can see the rea­son for their at­tach­ment to the ‘JC 3’ model num­ber. The JC stands for John Curl, of course, but long (and I mean long... it was ‘way back in the 70s) be­fore he started de­sign­ing for Para­sound, Curl was de­sign­ing for Mark Levin­son, for whom he de­signed the JC-1 head amp and JC-2 preamp. I guess that if you’re work­ing for some­one else, and they get to put their name on it (as in Mark Levin­son, who owned the com­pany back then, but sold it to Har­man, which is now owned by Sam­sung, and still makes prod­ucts car­ry­ing the Mark Levin­son brand), it’s only fair that your cre­ative in­put be ac­knowl­edged by in­clud­ing your ini­tials as part of the model num­ber. So why didn’t Curl’s ini­tials ap­pear on the prod­ucts he de­signed for Ven­detta Re­search, I hear some neo­phytes ask­ing? Quite sim­ply be­cause John Curl owned Ven­detta, it was his com­pany, so no need for ini­tials! (Though if he had added his ini­tials, it might have boosted the se­cond-hand prices of old Ven­detta Re­search prod­ucts.)

The equip­menT

In case you can’t tell from the photographs of the JC 3 Jnr in this re­view, it’s a full-width com­po­nent, the ‘stan­dard’ 437mm wide. It’s also a full-depth com­po­nent, the ‘stan­dard’ 375mm deep. The only thing that is not stan­dard is the height, which is a mere 64mm. And just in case you’re won­der­ing why I put the in­verted com­mas around the word stan­dard in the first two mea­sure­ments, and not in the third, it’s be­cause these days, I don’t think there is any real stan­dard in the width or depth of com­po­nents—di­men­sions are all over the shop. How­ever, the di­men­sions are cer­tainly the same as other Para­sound prod­ucts, so you’ll be able to ‘stack’ the JC 3 Jnr neatly if that’s what works for you. The size of the prod­uct does mean that there’s a lot of empty space in­side the JC 3 Jnr, but in the end I’d per­son­ally pre­fer to own a full-sized phono stage rather than a tiny lit­tle itty-bitty one crammed with cir­cuitry that was not even re­motely the size of any of my other equip­ment. How­ever the size of the case has a sig­nif­i­cant tech­ni­cal ad­van­tage, be­cause it al­lows Para­sound to keep the power sup­ply cir­cuitry a long way from the phono cir­cuitry.

De­spite the height of the JC 3 Jnr, Para­sound has in­cluded its trade-mark shal­low scal­lop that runs across the full width of the front panel, and into which the only two front-panel con­trols are fit­ted—a power switch at the left and a mono/stereo switch at the right. Al­though you can turn the power to the JC 3 Jnr on and off via this switch (der...), you can op­tion­ally elect to do this switch­ing by ap­ply­ing a 12 volt in­put from an­other com­po­nent, for auto switchon. How­ever, if you do this, the front panel switch is then dis­abled.

As for that mono/stereo switch­ing, it’s some­thing that’s of­ten left off phono pream­pli­fiers, but it’s ab­so­lutely es­sen­tial if you play mono LPs. How­ever, weirdly enough, I’ve found that switch­ing to mono can elim­i­nate the weird ‘phas­ing’ ef­fects that some­times hap­pen when you play well-worn LPs and can even re­duce the sur­face noise of noisy LPs though I re­ally don’t know why, and would al­ways rec­om­mend you re­move LP noise by clean­ing the record, rather than re­ly­ing on an elec­tronic ‘fix’.

Around the rear of the Para­sound JC 3 Jnr you’ll find there are gold-plated un­bal­anced in­put and out­put RCA sock­ets, and also rhodium-plated bal­anced XLR out­puts (made by Neu­trik).

Rather than sim­ply pro­vide ‘MM’ or ‘MC’ switch­ing (which in these days of high-out­put mov­ing-coil car­tridges and low-out­put mov­ing-mag­net car­tridges is no longer a re­ally ac­cu­rate way of de­scrib­ing which in­put you should use), the JC 3 Jnr sim­ply al­lows you to se­lect (via tog­gle switch) between ‘fixed’ in­put im­ped­ance (47kΩ) and ‘vari­able’ in­put im­ped­ance (50–500Ω), plus also se­lect between three gain set­tings:40dB, 50dB and 60dB (gain se­lec­tion is also via tog­gle switch).

The ‘vari­able’ set­ting is truly vari­able, be­cause it’s ac­com­plished via a ro­tary po­ten­tiome­ter—an ar­range­ment I can’t re­call ever hav­ing seen used be­fore for this pur­pose: it’s more usual to find DIP switches or PCB links. The prob­lem with us­ing po­ten­tiome­ters is that they’re in­her­ently noisy (which is why state-of-the art de­signs use re­sis­tor lad­ders to con­trol vol­ume, in­stead of po­ten­tiome­ters). Para­sound solved this prob­lem on the JC 3+ by ask­ing Alabama-based com­po­nent man­u­fac­turer Vishay to de­velop a cus­tom-made low-noise po­ten­tiome­ter specif­i­cally for the pur­pose of ad­just­ing car­tridge load re­sis­tance, and then us­ing two of them—one for each chan­nel. Un­for­tu­nately, these were so ex­pen­sive that Para­sound couldn’t in­clude them on the JC 3 Jnr, which uses just a sin­gle ‘off the shelf’—but very high-qual­ity—po­ten­tiome­ter.

Al­though Para­sound couldn’t keep the JC 3+’s Vishay pots, it did keep al­most ev­ery­thing else from the JC 3+, in­clud­ing what is fun­da­men­tally the same cir­cuit topol­ogy, the same pas­sive com­po­nents in the RIAA equal­iza­tion cir­cuitry, the FET fol­low­ers af­ter the power sup­ply that re­duce noise from the volt­age reg­u­la­tors and, also to re­duce noise, the high speed/soft re­cov­ery bridge diodes. With so much of the JC 3+’s DNA in­side the JC 3 Jnr, you might be ask­ing your­self what didn’t make it? Well I al­ready men­tioned the Vishay pots, but whereas the JC 3+ uses large, sep­a­rate power sup­plies for each chan­nel, the JC 3 Jnr uses a sin­gle and smaller power sup­ply for both chan­nels and whereas the left and right chan­nels of the JC 3+ are on com­pletely sep­a­rate PCBs, the same PCBs share the chan­nels on the JC 3 Jnr. Ap­par­ently both Schram and Curl were wor­ried about this un­til they saw and heard the re­sults of the PCB lay­out de­vel­oped by Carl Thomp­son, who de­signs all Curl’s PCBs. Says Schram: ‘We fret­ted over the de­sign and built nu­mer­ous pro­to­types be­fore we were sat­is­fied. Merely “great” was not an op­tion, and Carl Thomp­son played a large role with cir­cuit lay­outs that are in­spired, with out­stand­ing sepa­ra­tion and van­ish­ingly low noise. The JC 3 Jr. specs are amaz­ingly close to the JC 3+ specs that far sur­pass nearly any other phono stage.’ It’s for this rea­son that all the pub­lic­ity for the JC 3 Jnr says ‘ Cir­cuitry de­signed by leg­endary John Curl. Cir­cuit board lay­out by Carl Thomp­son.’ Maybe they should have called it the JCCT 3 Jnr?

The JC 3 Jnr is avail­able in sil­ver or black fin­ishes and there’s a rack-mount kit avail­able for it as well.

In Use and LIs­ten­Ing ses­sIons

Power-up the Para­sound JC 3 Plus and you’ll find that both front-panel but­tons have bright, deep-blue back­light­ing. In Stand-By mode the light­ing for the power but­ton dims slightly, while if you switch to ‘Mono’ the light­ing on the Mono/Stereo but­ton changes to a burnt orange colour. There are also loud ‘click’ sounds when you press the but­tons, so you don’t have to be look­ing to know you’ve pressed hard enough.

I should state at this point that I was ini­tially a bit bi­ased against us­ing a po­ten­tiome­ter to ad­just load im­ped­ance, not so much be­cause of the in­tro­duc­tion of noise, but be­cause of the seem­ing lack of pre­ci­sion, be­cause al­though the con­trol has marked po­si­tions for 50 to 550Ω in 10Ω in­cre­ments there is no guar­an­tee that the set­ting will be ex­act, whereas with a DIP switch, if you need an ex­act 110Ω load, you sim­ply switch in the 110Ω set­ting and it will be ex­actly that.

How­ever, af­ter dis­cussing the rel­a­tive mer­its of fixed vs. vari­able im­ped­ance ad­just­ments, I changed my think­ing. The most com­pelling rea­son I changed is that af­ter look­ing at ac­tual lab­o­ra­tory mea­sure­ments of the im­ped­ances of a va­ri­ety of phono car­tridges, I re­alised that al­though a car­tridge might be spec­i­fied as hav­ing an im­ped­ance of, say, 10Ω, vari­ances in the coil-wind­ing process mean that its ac­tual im­ped­ance might be any­where between 5Ω and 15Ω. Also, what­ever its ac­tual im­ped­ance, it’s only go­ing to be that at one fre­quency be­cause im­ped­ance, by def­i­ni­tion varies with fre­quency, so a nom­i­nally 10Ω car­tridge might ac­tu­ally have an im­ped­ance of 6Ω at 1kHz, and 14Ω at 10kHz. Also, of course, the im­ped­ance of one chan­nel of a phono car­tridge will rarely be the same as the im­ped­ance of the other chan­nel—which is pre­cisely why Para­sound puts two po­ten­tiome­ters on the JC 3+.

Once I’d changed my think­ing on this mat­ter, my de­ci­sion was set into con­crete when I started set­ting up the JC 3 Jnr, be­cause I re­alised that the huge ad­van­tage (and it is a huge ad­van­tage) a po­ten­tiome­ter has over DIP switches or links is the ease with which it’s pos­si­ble to fine-tune the im­ped­ance ‘on-the-fly’. So when set­ting up for my Kiseki Blue NS, for ex­am­ple, which has a d.c. re­sis­tance of 40Ω, and there­fore re­quires a min­i­mum load im­ped­ance of 400Ω (the rule of thumb for load im­ped­ance is 10× the d.c. re­sis­tance of the car­tridge), I was able to turn the pot to the 400Ω set­ting and then, while ac­tu­ally lis­ten­ing to an al­bum, ‘tweak’ the pot left and right by small amounts un­til I found the set­ting that sounded the best. This kind of ‘fine-tun­ing’ is im­pos­si­ble to do with DIP switches, and very time-con­sum­ing to do with links. (And, to prove the point, the best-sound­ing set­ting for the Kiseki was, in­deed, slightly higher at 460Ω.)

This 10× rule means that the max­i­mum d.c. re­sis­tance of any mov­ing-coil car­tridge you use should be at least 50Ω, which I am cer­tain will cover more than 90 per cent of the low-out­put mov­ing-coil car­tridges avail­able. Note, how­ever, that the 10× rule is not re­ally a ‘rule’ be­cause in the past I have found that mov­ing-coil car­tridges with im­ped­ances in the re­gion between 5–10Ω, which the rule would sug­gest should sound

The ‘vari­able’ set­ting is truly vari­able, be­cause it’s ac­com­plished via a ro­tary po­ten­tiome­ter

best with 50–100Ω load­ings, ac­tu­ally sounded the best when I used a 200Ω load im­ped­ance. Just say­ing. You can’t harm the car­tridge—or the phono pream­pli­fier—with an in­cor­rect set­ting, so feel free to ex­per­i­ment as much as you like. (Dan­ger Will Robin­son! You can, how­ever, dam­age your phono car­tridge by try­ing to mea­sure its d.c. re­sis­tance with a mul­ti­me­ter! In fact you’ll com­pletely de­stroy it if you try, so don’t even try it. You have been warned. Twice.)

Straight out of the box, with­out any warmup at all, the Para­sound JC 3 Jnr sounded great. Even while I was tweak­ing the car­tridge load im­ped­ance set­ting I was hear­ing ‘good’ ‘bet­ter’ ‘best’ as I made my ad­just­ments— never once did I hear any­thing that made me think ‘whoa, go back the other way fast!’

Sound­ing ‘great’ meant that I was hear­ing an ex­tended fre­quency re­sponse, so I was able to take ad­van­tage of the su­pe­rior high­end re­sponse of LPs—par­tic­u­larly those that had been half-speed mas­tered, which re­ally makes a dif­fer­ence when you’re lis­ten­ing to any in­stru­ment whose har­mon­ics ex­tend above 20kHz, and that’s quite a few of them, not just vi­o­lins and cym­bals and pi­anos and harp­si­chords and syn­the­sis­ers and flutes and pic­co­los… and more.

Gen­er­ally these high-pitched sounds are rather a long way back in the mix, so the fact that I was able to hear them so clearly was not just down to the Para­sound JC 3 Jnr’s ex­cel­lent high-fre­quency ex­ten­sion, but also be­cause of its re­ally low noise… so low, in fact, that I couldn’t hear any noise at all that I could at­tribute to the JC 3 Jnr when I was play­ing LPs. I even tried play­ing an ac­etate mas­ter with noth­ing recorded on it at all to see if I could hear any noise be­ing con­tribut- ed by the Para­sound and came up empty-handed. The end re­sult be­ing that with the JC3 Jnr you are go­ing to hear ev­ery­thing the record­ing en­gi­neer has cap­tured in the groove, and noth­ing more.

The Para­sound JC 3 Jnr was equally good at low fre­quen­cies. The Kiseki has an out­stand­ingly good bot­tom end, and the JC-3 al­lowed me to en­joy ev­ery bit of it. In fact it made my Kiseki sound even bet­ter, at least partly be­cause I haven’t quite got my ton­earm/car­tridge res­o­nance tun­ing ex­act, so al­though I can’t hear it be­cause the fre­quency is too low, I can see my woofers mov­ing as a re­sult of this res­o­nance, which I fig­ure means I must be get­ting some Dop­pler dis­tor­tion. With the Para­sound JC-3 in my rig, the woofer move­ment was much less, so I guess Para­sound must be rolling off the very low­est fre­quen­cies a bit. Since this is hap­pen­ing at fre­quen­cies lower than I can hear (so less than 15Hz) this worked for me, be­cause it means less Dop­pler dis­tor­tion and that my amps aren’t wast­ing any power try­ing to am­plify in­fra­son­ics I can’t hear.

Be­fore go­ing on I should note that one ‘fea­ture’ the Para­sound JC 3 Jnr does not have is se­lectable equal­i­sa­tion curves—you get the stan­dard RIAA curve and that’s it. I men­tion it be­cause I am per­fectly happy with stan­dard RIAA equal­i­sa­tion, be­cause I don’t own any discs pressed be­fore 1975.

If you’re read­ing this re­view, you most likely own a turntable and LPs but I guess you might not know what an RIAA curve is, since it’s so rarely men­tioned these days, so I’d bet­ter ex­plain be­fore go­ing any fur­ther.

When cre­at­ing a record by cut­ting a mas­ter disc, the groove that’s cre­ated is an ana­logue of the sound. So when the sound is loud, the width of the groove gets big­ger, and when the fre­quency is high, the ‘wig­gles’ in the groove are closer to­gether. The prob­lem is that the dy­namic range of sound is so great that with­out ad­just­ment, it could not be con­tained on a disc (or traced by a sty­lus, for that mat­ter). So in or­der to en­sure the disc is playable, the vol­ume of the low fre­quen­cies is re­duced prior to cut­ting the disc, and the vol­ume of the high fre­quen­cies is in­creased. This is called ‘pre-em­pha­sis’. It fol­lows, there­fore, that dur­ing re­play, the vol­ume of the low fre­quen­cies needs to be boosted back to the cor­rect level, and the level of the high fre­quen­cies re­duced to the cor­rect level. This is called ‘de-em­pha­sis’.

In the ear­li­est days of recorded sound, each record la­bel boosted and cut fre­quen­cies by dif­fer­ent lev­els, so if you played a record pressed by Columbia, you’d need to use a Columbia de-em­pha­sis fil­ter. If you played one pressed by Decca, you’d use a Decca de-em­pha­sis fil­ter. These fil­ters were on cir­cuit boards that you’d ‘plug-in’ to the rear of your am­pli­fier. Ob­vi­ously this sys­tem rapidly be­came un­work­able, not least be­cause of the ad­vent of low-cost por­ta­ble ma­chines, so the Record In­dus­try As­so­ci­a­tion of Amer­ica (RIAA) de­cided that all com­pa­nies man­u­fac­tur­ing LPs should stan­dard­ise on one par­tic­u­lar fil­ter that then be­came known as the ‘RIAA equal­i­sa­tion fil­ter’, al­low­ing elec­tron­ics man­u­fac­tur­ers to build the fil­ter in­side their prod­ucts, and elim­i­nat­ing the need for mul­ti­ple ‘plug-in’ fil­ters. The graph that shows the amount of boost and cut that ap­plies at each fre­quency is the RIAA curve—one curve for pre-em­pha­sis and then an equal but opposite curve for de-em­pha­sis.

So get­ting back to my orig­i­nal state­ment that I’m quite happy that the Para­sound JC 3 Jnr has only the stan­dard RIAA equal­i­sa­tion be­cause I don’t own any discs pressed be­fore 1975, this is be­cause ev­ery LP pressed af­ter this used RIAA pre-em­pha­sis. In fact, pretty much ev­ery stereo disc ever made was recorded us­ing RIAA equal­i­sa­tion. Even if you’re play­ing mono LPs, it’s likely that they were recorded us­ing RIAA equal­i­sa­tion, un­less they were recorded in the early 1950s, or ear­lier, in which case they might use one of the pro­pri­etary equal­i­sa­tions.

If you reg­u­larly play LPs that re­quire non-stan­dard equal­i­sa­tion (Decca, Columbia et al) and you de­mand ex­ac­ti­tude, you might pre­fer to buy a pream­pli­fier that has switch­able de-em­pha­sis, but LPs recorded with non-stan­dard equal­i­sa­tion will play back per­fectly well through the JC 3 Jnr—you’ll just get slightly dif­fer­ent lev­els of bass and tre­ble to what the record pro­ducer orig­i­nally in­tended.

The stereo imag­ing of the Para­sound JC 3 Jnr was su­perb. It will eas­ily be able to de­liver all the sepa­ra­tion avail­able from any phono car­tridge, so you’ll en­joy not only max­i­mum

In the end, it’s the sound that counts, and the sound of the Para­sound JC 3 Jnr is breath-tak­ingly beau­ti­ful!

stereo imag­ing, but also max­i­mal chan­nel iso­la­tion, so that if a sound is recorded solely in the left chan­nel, you won’t hear it from the right chan­nel, and vice versa. The chan­nel sepa­ra­tion of the Para­sound JC 3 Jnr is so good that I can’t imag­ine the Para­sound JC 3+ would be able to im­prove on it at all… though ad­mit­tedly I did not have one on hand to make the com­par­i­son.

Mu­si­cal de­liv­ery is im­pec­ca­ble. I just loved the way the Para­sound JC 3 Jnr de­liv­ered the elec­tron­ica of the The Pre­sets’ lat­est LP, ‘Hi Viz’, it pulsed with such vi­tal­ity that I played it sev­eral times over be­fore I re­mem­bered to record it to dig­i­tal whilst its grooves were still pris­tine. The choral echo on Down­town Shut­down was just so clean and real, then when the per­cus­sion and ef­fects join in the sound is amaz­ing. The looped sounds (beau­ti­fully de­liv­ered by the Kiseki by the way) were equally beau­ti­fully re­pro­duced by the JC 3 Jnr. I called it ‘elec­tron­ica’ but ap­par­ently Ju­lian Hamil­ton and Kim Moyes pre­fer to la­bel it ‘pub rock techno’— a la­bel that isn’t on the ‘Genre’ list of my mu­sic li­brary. You only have to lis­ten to Do What You Want to hear the ‘techno’, but I’m not so sure about the ‘pub’ bit. Maybe ‘dance floor’ or ‘rave’? Great al­bum though, just a pity we had to wait so long for it… and de­spite the love I’ve es­poused for it, I do pre­fer 2012’s ‘Paci­fica’.

Pi­ano is def­i­nitely one of the great­est in­stru­ments for as­sess­ing au­dio equip­ment, be­cause of its enor­mous dy­namic range and its ex­tended fre­quency range, but I get a bit bored with delv­ing back into the es­tab­lished reper­toire, so I can re­port my lat­est and great­est find (and a gift to mod­ern pi­ano mu­sic) is the al­bum ‘Solo’ by pi­anist Nils Frahm. Be­fore be­ing in­tro­duced to the al­bum (thanks Frank!) I’d never heard of Frahm, and I’d cer­tainly never heard of the pi­ano he’s play­ing, which is a Klavins M370 that’s ap­par­ently more than three me­tres tall long (yes, ‘tall’—not long—it’s a ver­ti­cal pi­ano) that has 10-foot strings. It was de­signed and built by a Ger­man-Lat­vian pi­ano maker David Klavins. Recorded in 2014, ‘Solo’ is an eight-track im­pro­vi­sa­tion that Frahm recorded in a sin­gle take, with­out any over­dubs, that’s now avail­able not only on LP, but also in 24-bit/48kHz dig­i­tal. The sound is as­ton­ish­ing. I’ve never heard pi­ano sound like it, and I don’t think I’ve ever heard a com­mer­cial record­ing like it. I won’t swear to it, but I’d bet se­ri­ous money there’s no com­pres­sion, no lim­it­ing, and no post-pro­duc­tion at all… just what was cap­tured by the mi­cro­phones. From the re­al­ity of the acous­tic of the record­ing venue to the res­o­nances from pi­ano, the hum­ming of the strings and the sheer sonor­ity of the sound, the whole ex­pe­ri­ence is truly hyp­notic and a true tour-de-force. If you’re into au­dio—and sound— you re­ally need to own this al­bum in what­ever for­mat takes your fancy, but if dig­i­tal’s your bag, you can down­load it for free here: http:// www.nils­

If you have the LP and you’re au­di­tion­ing a Para­sound JC 3 Jnr, pick a quiet time, drop on the LP, turn up the vol­ume, set­tle back and let it rip! Two tracks in and you’ll have for­got­ten all about the Para­sound JC 3 Jnr and just be rev­el­ling in the den­sity of the sound­field. But you’ll need to re­mem­ber it’s the Para­sound JC 3 Jnr that’s al­low­ing the sound to be this good. It has an in­cred­i­bly flat fre­quency re­sponse, so all those har­mon­ics and res­o­nances are trans­ferred per­fectly to your loud­speak­ers. Frahm is cur­rently on a world tour (in Aus­tralia next month) but if you want to go, get in early, be­cause he usu­ally sells out months in ad­vance of his con­cert dates.


In com­mon with all Para­sound’s prod­ucts, the JC 3 Jnr isn’t fancy-look­ing on the out­side— though it’s pretty fancy on the in­side—but in the end, it’s the sound that counts, and the sound of the Para­sound JC 3 Jnr is breath­tak­ingly beau­ti­ful. Hugh Dou­glas

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