LAVARDIN ISX REF­ER­ENCE IN­TE­GRATED AM­PLI­FIER

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Why would Lavardin, which is renowned for not up­dat­ing its prod­ucts, up­date its long­est-lived and most highly-awarded in­te­grated am­pli­fier? We couldn’t wait to find out…

IN­TE­GRATED AM­PLI­FIER

The Lavardin Model ISx Ref­er­ence in­te­grated am­pli­fier is en­tirely de­signed and man­u­fac­tured in France, and takes over from the Model IS Ref­er­ence, which was not only one of the com­pany’s long­est-lived prod­ucts (in con­tin­u­ous pro­duc­tion from 2001 to 2016), and one of its best-sell­ing am­pli­fiers, but also one of the com­pany’s most highly-awarded and best-re­viewed am­pli­fiers.

Given that Lavardin is well-known for not up­dat­ing its prod­ucts, I was cu­ri­ous about the rea­son for the change, be­cause it seemed to me that the only sub­stan­tive dif­fer­ence was the pro­vi­sion of a re­mote con­trol, plus a re­design of the front panel.

Ac­cord­ing to lo­cal Aus­tralian distrib­u­tor, Au­dio Magic, I was not en­tirely wrong. The front panel change was ap­par­ently to al­low the im­ple­men­ta­tion of a re­mote con­trol (though it re­mains a $250 op­tion—the base model still does not in­clude a re­mote con­trol).

Ac­cord­ing to Lavardin, it was not pos­si­ble to retro­fit re­mote con­trol to the chas­sis of the ear­lier model. It would also ap­pear that the front panel change has also en­abled coloured an­o­dis­ing op­tions that were not pre­vi­ously avail­able.

How­ever, there have been other changes, in­clud­ing that the ISx Ref­er­ence has a dif­fer­ent mains power trans­former to the IS Ref­er­ence, plus of course if you choose the re­mote op­tion, there’s a dif­fer­ent Alps vol­ume con­trol in­stalled (a mo­torised ver­sion, rather than the stan­dard man­ual ver­sion).

Au­dio Magic also says that the cir­cuitry has been changed in order to de­liver ‘ im­proved mu­si­cal­ity through more de­tailed mi­cro dy­nam­ics’, though no spe­cific de­tails of those changes were sup­plied.

How­ever, Jean Christophe Crozel, one of the two founders of Lavardin says: ‘ The im­prove­ment is so huge that a present Model ISx, with or with­out re­mote, on cer­tain as­pects, is more mu­si­cal and trans­par­ent than the pre­vi­ous Model IS Ref­er­ence or even the Model IT.’

THE EQUIP­MENT

The ex­ter­nal ap­pear­ance of the Lavardin Model ISx is, like all Lavardin mod­els, quite un­pre­pos­sess­ing, though ob­vi­ously quite work­man­like. My sam­ple was fit­ted with a red-coloured an­odized 5mm thick alu­minium front fas­cia that was bolted to a folded black an­odized al­loy chas­sis made of 3mm thick alu­minium. The red an­odiz­ing is ap­par­ently of­fered as a free op­tion. I rather liked the colour of the orig­i­nal an­odized fin­ish.

Source se­lec­tion is achieved us­ing the left-most knurled al­loy ro­tary con­trol on the front panel. Only four se­lec­tions are pos­si­ble, with the num­bers 1, 2, 3, and 4 in­scribed ver­ti­cally on the front panel to help with se­lec­tion, but a lay­out that means that the in­dent in the con­trol knob does not al­ways align ex­actly with the cho­sen in­put.

Vol­ume con­trol is achieved us­ing the right-most knurled al­loy ro­tary con­trol. (Just out of in­ter­est, Lavardin Tech­nolo­gies—or rather the com­pany be­hind Lavardin Tech­nolo­gies, which is called CEVL—makes all its own con­trol knobs in-house.

I can’t think of any cost-ef­fec­tive rea­son for do­ing this, so I can only as­sume they’re do­ing it solely to re­in­force the com­pany’s claim that the am­pli­fiers are made en­tirely in France… though, of course, many of the parts and semi­con­duc­tors in­side the am­pli­fier are made in coun­tries other than France.)

As you have gath­ered, you can order the Model ISx Ref­er­ence with a man­ual vol­ume con­trol, or one that’s able to be op­er­ated re­motely, via in­fra-red.

If you choose the re­mote con­trol op­tion (and why wouldn’t you… be­ing able to ad­just vol­ume from the com­fort of your lis­ten­ing po­si­tion is a no-brainer) you’ll be in­ter­ested to find that CEVL says it has de­signed its re­mote con­trol cir­cuitry so that it is ‘ com­pletely pas­sive’ when­ever a re­mote sig­nal is not be­ing re­ceived. The com­pany says that the in­fra-red cir­cuitry found in all other re­mote con­trol­lable am­pli­fiers is con­stantly ac­tive, and as a re­sult af­fects the au­dio cir­cuitry within those am­pli­fiers.

A state­ment from the com­pany ad­vises (ver­ba­tim): ‘ There is no per­ma­nent clock­ing sig­nal to be used by the IR decoder in­side the am­pli­fier. The re­ceiver and the decoder are « pas­sive » and the clock­ing of the IR sig­nal is made in the emit­ter only and when sig­nals are sent only. Thus there is no per­ma­nent sig­nal pol­lu­tion in­side the am­pli­fier due to the per­ma­nent clock­ing of ALL clas­si­cal IR re­ceivers and de­coders.’

Mid­way be­tween the two ro­tary con­trols is a cut-out in the front panel that is backed by a metal plate that con­tains the IR sen­sor (left), and a red LED to in­di­cate that the mains power is on (cen­tre). The cir­cu­lar fea­ture at the right ap­pears to be just that—a cir­cu­lar fea­ture that bal­ances the ap­pear­ance of the plate.

The stan­dard Lavardin Model ISx Ref­er­ence comes with four line-level in­puts, all able to be con­trolled via the vol­ume con­trol. You can, how­ever, ask for a ‘By­pass In­put’ to be fit­ted, in which case the fac­tory will hard­wire In­put 1 so that it by­passes the vol­ume con­trol cir­cuitry and goes di­rectly to the am­pli­fier cir­cuit, for the pur­pose of, ac­cord­ing to Lavardin Tech­nolo­gies’ ‘User Guide’, ‘ smooth in­te­gra­tion of a sur­round pro­ces­sor into high end au­dio sys­tem’ (sic).

An­other op­tion avail­able for the Lavardin Model ISx Ref­er­ence is a mov­ing-mag­net phono stage. If this is fit­ted (as it was on the model I was loaned for this re­view) it ‘takes away’ one of the four line in­puts (In­put 4). This means that if you op­tion in both the By­pass and the Phono in­puts, you’re es­sen­tially left with only two line-level in­puts: In­put 2 and In­put 3, which may or may not be suf­fi­cient for your needs, de­pend­ing on the num­ber of line-level sources you use in your sys­tem.

If you don’t op­tion in the phono cir­cuit, the price of the Lavardin Model ISx Ref­er­ence (in­clud­ing re­mote) drops to $6,200 (RRP).

What is not avail­able, either stan­dard or as an op­tion, is a head­phone out­put. These days, with so many peo­ple us­ing head­phones for lis­ten­ing—some­times even as a pref­er­ence over loud­speak­ers, it’s rare to find an am­pli­fier with­out a head­phone socket… even if it’s some­time rather in­con­ve­niently lo­cated on a side or rear panel, so the Lavardin Model ISx Ref­er­ence is def­i­nitely an out­lier in this re­gard.

Turn­ing to the rear panel of the Lavardin Model ISx Ref­er­ence, quite frankly I found it—and the fit­tings on it—not at all what I’d ex­pect to find on any com­mer­cial am­pli­fier, and most cer­tainly not one stick­ered at close to $7,000. Firstly, rather than screen-print­ing iden­ti­fiers on the rear panel, CEVL is in­stead us­ing low-cost stick-on alu­minium la­bels to iden­tify the in­puts and out­puts, as well as to pro­vide model num­ber and reg­u­la­tory in­for­ma­tion. One of the la­bels on my sam­ple was not even at­tached straight. Also, as you can see from the pho­to­graph of the rear panel, CEVL has made one of the two stickon la­bels ‘multi-pur­pose’ by print­ing ‘Phono’ un­der ‘Line 4’ and ‘By­pass’ un­der ‘Line 1’, so when you spec­ify an op­tion, the tech­ni­cian who as­sem­bles your unit sim­ply crosses out with black ink the word(s) that do not ap­ply. Alu­minium la­bels are very in­ex­pen­sive, so if you’re go­ing to use them, rather than a prop­erly screen-printed panel, why not have four dif­fer­ent la­bels?

As for the fit­tings on the rear, the speaker ter­mi­nals—al­beit gold-plated—are a low-cost type that is sold in Aus­tralia by the hobby elec­tron­ics re­tailer Jay­car. Above them are four holes that have been plugged with plas­tic in­serts, which smacks of ama­teurism. It may be that CEVL is re-pur­pos­ing this chas­sis from an­other model as a cost-cut­ting mea­sure, or is in­tend­ing to of­fer a bi-wired ver­sion at some point in the fu­ture, but none of this is what I ex­pect to see on an am­pli­fier re­tail­ing at the ISx Ref­er­ence’s price. At the far left there’s even a hole in the chas­sis that isn’t plugged at all… it’s just a hole. I as­sumed it was for the ground post that usu­ally ac­com­pa­nies the fit­ting of a phono cir­cuit, but al­though my am­pli­fier had been fit­ted with just such a cir­cuit, as men­tioned, there was no ground post on my sam­ple.

What you also may have noted from the pic­ture of the rear panel is that the speaker ter­mi­nals are not iden­ti­fied as pos­i­tive or neg­a­tive, though I’d guess that red is pos­i­tive. More im­por­tantly, they aren’t iden­ti­fied as ‘Left’ or ‘Right’ either. Nei­ther are the RCA in­puts iden­ti­fied as be­ing ‘Left’ or ‘Right’, though they do have very tiny coloured col­lars, with the row at the top hav­ing red-coloured bands and the ones at the bot­tom hav­ing black coloured bands. I as­sumed that red=right and black=left, but when I hooked the am­pli­fier, the right-most speaker ter­mi­nals were ac­tu­ally the left chan­nel if I used this hook-up sys­tem! And just in case you were won­der­ing, there are no ex­pla­na­tions or il­lus­tra­tions in Lavardin Tech­nolo­gies’ ‘User Guide’ either… you’re on your own work­ing out what’s what. (Edi­tor’s Note: Your hi-fi dealer would be able to ad­vise you about all these points… which is an ex­cel­lent rea­son to make sure you buy only from an au­tho­rised re­tailer.)

In­ter­nally, al­most all the cir­cuitry is con­tained on a sin­gle PCB. Rather un­usu­ally these days, that PCB is pop­u­lated en­tirely by through-hole com­po­nents rather than sur­face mount de­vices. In­com­ing a.c. from the shielded en­cap­su­lated toroidal power trans­former is rec­ti­fied by four dis­crete diodes, rather than a diode bridge, and the re­sul­tant d.c. is smoothed by four small elec­trolytic ca­pac­i­tors. Be­cause these ca­pac­i­tors are mounted ver­ti­cally di­rectly to the main PCB their size is nec­es­sar­ily lim­ited by the height of the chas­sis, so they’re only 10,000μF, 40VW types.

One ‘fea­ture’ of the PCB is the use of en­cap­su­lated cir­cuitry that is in­volved in elim­i­nat­ing in the Lavardin ISx Ref­er­ence what the late Gérard Per­rot (the other co-founder of Lavardin) re­ferred to as ‘ mem­ory distortion.’ The epoxy en­cap­su­la­tion is pre­sum­ably in­tended to pre­vent in­dus­trial es­pi­onage of the ‘mem­ory distortion’ cir­cuitry, but it also makes it im­pos­si­ble for a third party to re­pair the am­pli­fier in the event that one of the en­cap­su­lated com­po­nents fails. This might mean the am­pli­fier has to be re­turned to France (easy if you live in Europe, but rather ex­pen­sive if you live in Aus­tralia) or that you have to re­place an en­tire PCB… which would also be ex­pen­sive. Of course any fail­ures within the first year of own­er­ship would be re­paired for free by which­ever re­tailer sold you the am­pli­fier, but out­side this pe­riod, it will be the owner who has to bear all the costs.

It’s be­cause of this en­cap­su­lated cir­cuitry, that I per­son­ally think Lavardin should fol­low the lead of other am­pli­fier man­u­fac­tur­ers and of­fer a 10-year or prefer­ably a 20-year war­ranty on its am­pli­fiers.

What is ‘mem­ory distortion’? Ac­cord­ing to the Lavardin web­site: ‘ Mem­ory distortion is the prop­erty that is the dom­i­nant fac­tor in caus­ing solid-state am­pli­fiers to sound shrill and me­chan­i­cal. Tube tech­nol­ogy al­lows elec­trons to travel through a vacuum which leaves no stor­age or mem­ory ef­fect, but solid-state am­pli­fiers use sil­i­con com­po­nents which keep a trace of cur­rent flow that has gone through. New elec­tron flow is con­tin­u­ously af­fected by the pat­tern of the im­me­di­ately pre­ced­ing elec­tron flow. As soon as the mem­ory ef­fect of these solid state cir­cuits is re­duced, all the im­prove­ments that tran­sis­tor tech­nol­ogy brings, such as high out­put power, ac­cu­racy, very low har­monic distortion and ex­tended and lin­ear fre­quency re­sponse, can be added to the most alive and silky mu­si­cal ren­di­tion of the best sin­gle-ended monotri­ode de­signs.’

CEVL claims that it is the only com­pany in the world that can mea­sure mem­ory distortion: ‘ The mem­ory distortion of com­po­nents was dis­cov­ered en­tirely by Lavardin Tech­nolo­gies en­gi­neers, as are the pro­ce­dures for mea­sur­ing the very au­di­ble distortion which re­sults from it’, and that be­cause of mem­ory distortion, all lab­o­ra­tory mea­sure­ments are mean­ing­less: ‘ the clas­sic mea­sure­ments made all over the world for the last decade are mean­ing­less when con­sid­er­ing the mu­si­cal qual­ity of an am­pli­fier,’ writes Lavardin Tech­nolo­gies on its site.

All of which might ac­count for the choice of the out­put tran­sis­tors used in the Lavardin Model ISx Ref­er­ence am­pli­fier: two pairs of TIP142/147 (the ones fit­ted to my sam­ple be­ing made by STMi­cro­elec­tron­ics). These de­vices are ac­tu­ally Dar­ling­ton pairs which means that al­though each one looks like an or­di­nary tran­sis­tor, with three ter­mi­nals (base, emit­ter, ground), each one has in­side two tran­sis­tors, two re­sis­tors and a diode. These de­vices can han­dle 5 amps and 100 volts and are renowned for their rugged­ness, which finds them oft-used in lin­ear and switch­ing in­dus­trial ap­pli­ca­tions, but they’re also pop­u­lar with DIY builders due to their low cost.

The out­put tran­sis­tors (and, in turn, your loud­speak­ers) are pro­tected by fast-blow 2A fuses. This means that when con­tin­u­ous cur­rent draw ex­ceeds two am­peres the fuses might blow. Mu­sic sig­nals are not con­tin­u­ous of course, so av­er­age out­put power would have to be very high for a fuse to blow, but 2A seemed a fairly low value for an am­pli­fier that is rated at 104-watts into 2 . When I checked Lavardin Tech­nolo­gies’ User Guide, it seems that this claimed out­put power is ac­tu­ally only a the­o­ret­i­cal value, be­cause the User Guide specif­i­cally states that the am­pli­fier ‘ is in­tended to part­ner with loud­speak­ers whose im­ped­ance is 5 ohm or more.’ This be­ing the case, it would rule out the use of speak­ers with nom­i­nal im­ped­ances of 2 … or even 4 with the Model ISx Ref­er­ence.

In­stead of us­ing a con­ven­tional finned heatsink ex­tru­sion to keep the out­put tran­sis­tors at the cor­rect op­er­at­ing tem­per­a­ture, CEVL has clamped the four out­put de­vices to an L-shaped sec­tion of alu­minium al­loy that is riv­eted to the base of the chas­sis, es­sen­tially us­ing the en­tire chas­sis of the am­pli­fier to dis­si­pate heat, which is why there are no cool­ing vents in the chas­sis.

If you order the re­mote con­trol ver­sion of the Lavardin Model ISx Ref­er­ence you may be dis­ap­pointed to dis­cover that you can only use it to ad­just vol­ume. You can­not use it to switch sources… in­deed there isn’t even a mute func­tion. As you can see from the pho­to­graph, nei­ther does it look like a pro­fes­sion­ally-made prod­uct. In­deed I would not be the first re­viewer to re­mark that it looks like it was built by a high-school stu­dent for a De­sign & Tech­nol­ogy as­sign­ment, be­cause a re­viewer for that well­known UK pub­li­ca­tion What Hi-Fi? al­ready beat me to it. [ www.tinyurl.com/ISx-Ref-Rev]

The Lavardin ISx Ref­er­ence in­te­grated am­pli­fier is nei­ther large nor heavy, mea­sur­ing 700×430×306mm and weigh­ing 6kg.

IN USE AND LIS­TEN­ING SES­SIONS

Con­nect­ing the Lavardin Model ISx Ref­er­ence to my ref­er­ence sys­tem was a lit­tle trick­ier than usual, due to the lack of iden­ti­fi­ca­tion on the rear panel and the equal lack of in­for­ma­tion in the ‘User Guide’. These short­com­ings could eas­ily be reme­died by Lavardin Tech­nolo­gies and it’s ex­pected that the com­pany will do so in the very near fu­ture, but in the in­terim it meant that I had to use test equip­ment to es­tab­lish be­yond any doubt the ab­so­lute phase of the speaker ter­mi­nals, and also to es­tab­lish that the left chan­nels (both from my CD player and my turntable) were in fact de­liv­er­ing in­for­ma­tion via the am­pli­fier to my left chan­nel speaker. (That said, it could be worse: Some years ago, Aus­tralian Hi-Fi Mag­a­zine re­viewed a valve am­pli­fier built by a fa­mous Ital­ian man­u­fac­turer whose clearly marked left chan­nel was ac­tu­ally the right chan­nel, and vice versa!)

Rather un­usu­ally, Lavardin says that all its am­pli­fiers ‘ are fully ready to de­liver all their mu­si­cal qual­ity within 5 or 10 min­utes of func­tion at do­mes­tic tem­per­a­ture. No burn-in is nec­es­sary once the am­pli­fier is realeased (sic) by the fac­tory,’ which suited me fine, as I was able to play ‘Self Talk’, which is cur­rently one of my high-ro­ta­tion al­bums, straight away. Self Talk is by Mel­bourne-based singer/ in­stru­men­tal­ist Olympia, whose real name is Olivia Bart­ley. It’s a (mostly) densely multi-lay­ered work, with sounds and sonic ef­fects fir­ing at you from all direc­tions, but with Olympia’s fab­u­lous voice al­ways at the fore, and many times ac­com­pa­nied by her own voice so­lus, cho­rused, or asided. I don’t know how many hours she spent in the stu­dio, but it must have been thou­sands… and it was cer­tainly time well-spent. The track Blue Light Disco is prob­a­bly my favourite— son­i­cally sur­real with a foggy, at­mo­spheric sound that cap­ti­vates ev­ery sense and a good au­ral taster if you don’t want to au­di­tion the com­plete al­bum.

There are cer­tainly plenty of sounds on Self Talk that can be used to high­light the Lavardin ISx Ref­er­ence’s own per­for­mance, which I found to be ex­cep­tion­ally good. On the track Open­ing Hours the Lavardin ISx Ref­er­ence de­liv­ered a per­fectly paced per­for­mance, so I was able to clearly hear the com­plex cross-rhythms that per­me­ate it. At the same time, the per­fect clar­ity of the am­pli­fier—and the sep­a­ra­tion be­tween the chan­nels— meant I was hear­ing the de­lib­er­ate sonic dis­tor­tions in the right chan­nel whilst at the same time hear­ing the equally de­lib­er­ate pu­rity of the sound in the left chan­nel as purely as freshly fallen snow.

The depth and lux­u­ri­ous­ness of the bass the Lavardin ISx Ref­er­ence could de­liver was eas­ily ev­i­denced on Honey, a song which Olympia says: ‘ is es­sen­tially about the in­flu­ence we have on each other, and that mo­ment when some­thing hap­pens and you have this, is-that-who-I-am? mo­ment.’

I find the whole al­bum to be rather like a med­i­ta­tion. Once it’s play­ing, you can’t help but move deeply into the mu­sic and be­come com­pletely ab­sorbed within it. If it’s a telling point—and I think it is—I have to say that when lis­ten­ing us­ing the Lavardin ISx Ref­er­ence, I was able to en­ter the med­i­ta­tive state smoothly, eas­ily, and very quickly.

I am a great fan of us­ing spo­ken word to eval­u­ate speak­ers and am­pli­fiers and I’ve fi­nally found a spo­ken word al­bum—of sorts— that’s also lots of fun to lis­ten to, which is help­ful if you’re lis­ten­ing over and over again try­ing to pin down the finer points of a com­po­nent’s sound qual­ity.

That al­bum is Kate Tempest’s ‘Let Them Eat Chaos’. Tempest is a UK per­for­mance poet who works with mu­sic as her back­ground… in much the same way as Patti Smith when she started out. The Lavardin ISx Ref­er­ence proved it­self able to de­liver the tone of Tempest’s voice with supreme ac­cu­racy and in­cred­i­ble in­tel­li­gi­bil­ity. And when she gets into struc­tured rap­ping, her pac­ing is de­liv­ered with to­tal ex­ac­ti­tude by the Lavardin ISx Ref­er­ence.

On Pic­ture a Vacuum, which sets the scene of what’s to come (the tracks de­scribe seven peo­ple who live on the same street but who have never met, af­ter which a storm causes them to meet and see each other for the very first time), the 25-se­cond pre­lude is spo­ken against a silent back­ground, giv­ing am­ple op­por­tu­nity to ap­pre­ci­ate the to­tal lack of cir­cuit noise from the Lavardin—this is one silent am­pli­fier. It’s an im­pres­sive al­bum, and the Lavardin ISx Ref­er­ence gave an equally im­pres­sive per­for­mance of it.

By now you’re prob­a­bly ask­ing: ‘ But can the Lavardin ISx Ref­er­ence rock ‘n’ roll?’ You bet it can! I fired up ‘Beg­gar’s Ban­quet’, which con­tains one of my all-time favourite Rolling Stones songs… no, cor­rect that, one of my all-time favourite songs: Sym­pa­thy for the Devil. I only have to hear that un­miss­able pi­ano/bass/ conga in­tro­duc­tion and I’m straight out of my

chair to sing along with Mick the lyric that has to be one of the great­est in rock. Wy­man’s bass line matches Watts’ syn­co­pa­tion yet he also man­ages to colour it by throw­ing in ex­tra lines from left field. And the (ap­par­ently serendip­i­tous) ‘woo woos’ that kick in after­wards be­come in­creas­ingly in­tox­i­cat­ing.

But it isn’t only the mu­sic of Sym­pa­thy for the Devil that is so cap­ti­vat­ing. The words are so poetic and mas­ter­ful—and so full of im­agery and es­o­teric his­toric ref­er­ences—that I still some­times won­der if they were re­ally writ­ten by the band or by some mys­te­ri­ous un­named lyri­cist. There’s cer­tainly lit­tle other like it in the Stones’ oeu­vre… think about the lyrics to Sat­is­fac­tion or Jumpin’ Jack Flash by way of com­par­i­son. How can ‘ I can’t get, no o o, sat-is­fac­tion’ (re­peat ad in­fini­tum) pos­si­bly com­pare with ‘ And I was ‘round when Je­sus Christ/Had his mo­ment of doubt and pain. Made damn sure that Pi­late/Washed his hands and sealed his fate’?

The Lavardin ISx Ref­er­ence just nailed this song… it nailed the whole al­bum in fact. Yep, this am­pli­fier can re­ally rock!

But if you are want­ing the Lavardin ISx Ref­er­ence to rock at head-bash­ing lev­els, you’d bet­ter make sure you have ef­fi­cient loud­speak­ers, be­cause I could drive the am­pli­fier’s out­put stage into clip­ping if I wound the wick up… though ad­mit­tedly I was us­ing in­ef­fi­cient (84dBSPL) speak­ers with a fairly high (8 nom­i­nal) im­ped­ance. In­ter­est­ingly, al­though I could hear the clip­ping, the fuses didn’t blow, so there are un­likely to be any ‘false’ de­tec­tions that would ne­ces­si­tate an­noy­ing fuse re­place­ments (which would also in­val­i­date the war­ranty if they were to be user-ex­e­cuted). And the vol­ume level I had to play in order to cause the am­pli­fier to clip was so high that I’d say that as long as your speak­ers are some­where in the ball­park of 90dBPSPL ef­fi­ciency (and prefer­ably have a nom­i­nal im­ped­ance of 6–8 ) you’ll eas­ily be able to play the Lavardin ISx Ref­er­ence at lev­els that will be ‘too loud for com­fort’ in all but the largest of lis­ten­ing rooms.

CON­CLU­SION

The Lavardin Model ISx Ref­er­ence in­te­grated am­pli­fier has a smooth and en­chant­ing sound qual­ity that’s en­tirely mu­si­cal and beau­ti­fully de­tailed, while also be­ing truth­ful in terms of tonal ren­di­tion. It’s a su­perb-sound­ing am­pli­fier in ev­ery aspect. Tony Si­mon­etti

‘When it is about max power mea­sure­ments with con­tin­u­ous si­nus sig­nals, of course it is dif­fer­ent. We are not sure that mea­sur­ing a few watts more or less, deal­ing with 0,5dB more or less sound pres­sure at max level will bet­ter de­scribe am­pli­fiers.’] Need­less to say you should NOT re­place the 2A fuses with 3.15A types, as this would in­val­i­date the war­ranty and could po­ten­tially re­sult in dam­age to the am­pli­fier it­self and/or your loud­speak­ers.

At an out­put level of one watt, with a 1kHz test sig­nal (Graph 1), distortion was very low. There’s a se­cond har­monic com­po­nent at –100dB (0.001%), a third har­monic at –111dB (0.00028%), a fourth at –119dB (0.00011%), then fifth and sixth har­mon­ics at around –110dB (0.00031%), fol­lowed by a sev­enth at –115dB (0.00017%) and an eighth at –117dB (0.00014%). The few other higher-order har­monic distortion com­po­nents are all more than 116dB down (0.00015%). The sig­nals vis­i­ble at the ex­treme left of the graph are low-fre­quency sig­nals from the power sup­ply: 50Hz and the re­lated har­mon­ics thereof. All of this sums to a to­tal THD+N fig­ure of 0.016%, as you can see on the tab­u­lated re­sults, which is ex­cel­lent—well be­low the thresh­old of au­di­bil­ity.

Distortion at one watt into 4 (at 1kHz) was a lit­tle higher than into an 8 load, but still very low. The only real dif­fer­ences are that the se­cond har­monic in­creases to –92dB (0.00251%) and that a 10th har­monic (at 10kHz) ap­pears at a level of –106dB (0.0005%). An­other dif­fer­ence is a slight in­crease in the noise floor at the lower im­ped­ance. Whereas at 1-watt out­put into 8 the noise floor av­er­ages around –125dB, it in­creases to about –122dB into 4 (ref­er­enced to 1-watt out­put).

Graph 3 shows distortion at the Lavardin ISx Ref­er­ence’s rated out­put power of 45-watts (a mea­sure­ment made pos­si­ble be­cause only a sin­gle chan­nel is driven when test­ing distortion lev­els). Al­though al­most all har­mon­ics (odd and even) are present in the out­put, with the ex­cep­tion of the third har­monic at –94dB (0.00199%) the first five har­mon­ics are more than 100dB down (0.001%) and all of the oth­ers are close to or more than 110dB down (0.00031%). Low fre­quency mains-re­lated noise (ex­treme left of the graph) is very low, and the over­all noise floor of the am­pli­fier has dropped to –140dB (ref­er­enced to rated out­put). Again, this is a truly ex­cel­lent re­sult, with the summed THD+N fig­ure be­ing an ex­cep­tion­ally low 0.0071%.

In­ter­mod­u­la­tion distortion (CCIF-IMD) was spec­tac­u­larly low, as you can see from Graph 5. There are only two sig­nif­i­cant side­bands either side of the 19kHz and 20kHz test sig­nals, and both are 100dB down (0.001%). There is an un­wanted re­gen­er­ated sig­nal down at 1kHz, but it’s right down at around –110dB (0.00031%). It ap­pears there is also un­wanted sig­nal at 2kHz, but this is at –114dB (0.00019%), so not at all sig­nif­i­cant, since it would be in­audi­ble.

The fre­quency re­sponse of the Lavardin ISx Ref­er­ence, as mea­sured by New­port Test Labs, was beau­ti­fully ex­tended at low fre­quen­cies, ex­tend­ing to well be­low 1Hz, but not quite so much at high fre­quen­cies, where it was mea­sured as be­ing 1dB down at 16kHz, 1.4dB down at 20kHz and 3dB down at 32kHz. Two fre­quency re­sponse traces are shown in Graph 4. The black trace shows the Lavardin ISx Ref­er­ence’s re­sponse into a stan­dard 8 non-in­duc­tive lab­o­ra­tory test re­sis­tor. The red trace shows the Lavardin ISx Ref­er­ence’s fre­quency re­sponse when it’s driv­ing a load that’s rep­re­sen­ta­tive of a typ­i­cal two-way loud­speaker sys­tem. (Es­sen­tially this cir­cuit is the one orig­i­nally de­vel­oped by Ken­neth E. Kan­tor ( Acous­tic Re­search, NHT, Tym­phany, ZT Am­pli­fiers) but mod­i­fied by John Atkin­son ( Stereophile) with a Zo­bel net­work, the schematic for which can be found here: www. tinyurl.com/sim-ls-load You can see that the trace into the sim­u­lated load is very sim­i­lar to that into a re­sis­tive load, in­di­cat­ing that the Lavardin ISx Ref­er­ence will be load-in­vari­ant so far as fre­quency re­sponse is con­cerned. It also pre­dicts a high damp­ing fac­tor, mean­ing that this am­pli­fier will be able to main­tain good con­trol over the un­wanted mo­tion of large loud­speaker cones. As you can see from the tab­u­lated re­sults, the test for out­put im­ped­ance showed that of the Lavardin ISx Ref­er­ence to be 0.12 , re­sult­ing in a damp­ing fac­tor of 66 at 1kHz.

This is not ex­ces­sively high, but it’s more than re­quired to pro­duce re­sults that are in­dis­tin­guish­able with higher damp­ing fac­tors in lis­ten­ing tests… at least ac­cord­ing to ex­ten­sive re­search con­ducted by Floyd E. Toole when he was work­ing for the Na­tional Re­search Coun­cil in Canada.

Chan­nel sep­a­ra­tion was far greater than will be re­quired to de­liver per­fect stereo imag­ing, and re­mark­ably uni­form, av­er­ag­ing around 74–75dB ir­re­spec­tive of test fre­quency. Chan­nel bal­ance was also ex­cel­lent, at 0.13dB (at 1kHz).

New­port Test Labs mea­sured the signalto-noise ra­tio of the Lavardin ISx Ref­er­ence as 85dB A-weighted when ref­er­enced to a one-watt out­put, and 97dB A-weighted when ref­er­enced to its rated out­put. These are very good re­sults, par­tic­u­larly the 97dBA re­sult, as it’s ref­er­enced to the rated out­put of just 45-watts. (When a sig­nal-to-noise ra­tio is ref­er­enced to rated out­put, the re­sult will al­ways ‘im­prove’ for am­pli­fiers that have a higher rated out­puts, which is why Aus­tralian Hi-Fi Mag­a­zine al­ways in­cludes a S/N fig­ure that’s ref­er­enced to an out­put of one watt, as this is the only fig­ure that puts all am­pli­fiers on an equal foot­ing when you’re com­par­ing sig­nal-to-noise ra­tios.)

The Lavardin Model ISx Ref­er­ence’s per­for­mance with a 100Hz square wave was ex­em­plary, as you can see for your­self in the os­cil­lo­gram ac­com­pa­ny­ing this re­port: ab­so­lutely no tilt at all. The 1kHz square wave shows a lit­tle round­ing, as only to be ex­pected given the am­pli­fier’s early-ish high-fre­quency roll-off, while the 10kHz square wave’s lead­ing edge is se­verely rounded—a di­rect re­sult of the afore­men­tioned high-fre­quency roll-off. Into a highly reactive load the square wave shows around three cy­cles of ring­ing, each one be­ing pro­gres­sively damped, af­ter which com­plete sta­bil­ity is achieved: a re­sult that’s fairly typ­i­cal of a well-de­signed in­te­grated am­pli­fier.

The idle power con­sump­tion of the Lavardin ISx Ref­er­ence was mea­sured as 23.78 watts, so it will draw about the same as a sin­gle halo­gen light bulb from your 240V mains sup­ply whilst ever it is switched on (there is no stand-by power fea­ture).

When you’re us­ing the am­pli­fier, it will pull be­tween 36 and 165-watts from your mains, de­pend­ing on how loudly you’re play­ing your mu­sic. War­wick Mars­den

The speaker ter­mi­nals are not iden­ti­fied as pos­i­tive or neg­a­tive.nor are they iden­ti­fied as ‘Left’ or ‘Right’. The RCA in­puts are not iden­ti­fied either.

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