Manuel d'utilisation / d'entretien du produit Isis du fabricant Avalon Acoustics
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D ESIGNED BY N EIL P ATEL FOR A V A LON A COUSTICS This product is cert ified to meet the requirement s of the European Un ion (EU) Electromagnet ic Compatibility (EM C) Di rective (89/336/EEC ).
Table of Contents 1 Introduction ............................................................................................................................ 4 2 Unpacking Instr uctions .................................................................
9 Accuracy of Bas s Reproduction .......................................................................................... 33 Introduction .......................................................................................................... 33 9.
4 1 Introduction is the most technologic ally adva nced h igh -energy transducer ever created. Our foc used research over a p eriod of four years ha s produced a range of advanc ements in ea ch aspect of loudspeaker perf orman ce.
5 2 Unpacking Instructions Introduction Your A VALON A COUSTICS loudspeakers w ere shippe d in a two heavy- duty c rates to ensure t heir safe arrival. It is rec ommen ded to save these crates for possi ble future use. D ue t o the weight of the speakers, it will req uire two persons t o un -crat e them a nd position them for li stening.
6 2.1 Opening the Crate The crate features a one -pi ece top assembly wh ich is fastened t o the crate bottom wit h screws around the low er perimeter. T o unpack, remove the screws a nd li ft th e upper port ion of the crate st raight up (this w ill require two people).
7 2.2 Installing the Grilles The grille assemblies are behin d a panel on t he outside of the speaker crat e. Remove the screws securing the panel, and then carefully pull the grilles straight out. The gri lles are i nstalled with friction fasteners and p ress int o p lace on the speaker ca binets.
8 2.3 Replacing Grille Pins The grille pins i nstalled on the gri lle assemblies are fragil e and can be easily damaged. Should a ny of t he p ins break, you may repl ace t hem using t he following p rocedure. 1. Plac e t he gri lle a ssembly face -dow n on a p added surface (a towel or carpetin g).
9 4. Carefully p ull the grille cloth awa y from the frame mounting hole. The mounting hole must be clear of all obst acles durin g pin inst allation. 5. Place the exposed en d of t he grille pin in the open mounting hole. Che ck to insure that th e grille cloth is not trap ped between the pin and frame.
10 3 Wiring Instructions Introduction The crossover i s encapsula ted in a sealed, non-acc essible chamber in the bottom of the speaker cabinet, to minimi ze the effec t of vibrat ion on the components . The ISIS is equipped with high-quali ty binding posts for connecting the spea ker cables.
11 4 Break-in Period Your new A VA LON A COUS TICS loud speakers have an initial b reak- in peri od. They will not perform t o their full sonic p otentia l when first in stalled in your system. This i s pa rtially due to a residual polarization of th e dielectri c mat erials used in the crossover capacitors and internal wiring.
12 5 Maximizing Performance These details are im perative to obtain ing optimum results from your A VALON A COUSTICS loudspeakers. Break- in The break -in period i s critical t o maxi mizing sonic performanc e and should take place before ot her adjustmen ts (see t he di scussion on page 11 ).
13 Toe- In Adjusting the toe -in angle of th e speakers is useful in t ailoring t he sound to best mat ch the characteristic s of your system and li stenin g room. When t he speakers are fac ing stra ight forward, t hey tend to crea te a large, expansive so und-st age, pai nted w ith broad b rush strokes.
14 First Reflection Points Since t he ear/b rain system tends to i ntegrate t he sound s arriving w ithin a 10 millisecond time wi ndow, it is important to control the early reflec tions arri ving from t he sidewal ls to th e list ening position.
15 6 Care of Your Loudspeakers Cabinet (Hardwood Finis h) A VALON A COUSTICS ’ hardwood finished loudspea kers are supplied w ith a special p olish and two lint - free polishing cloths, in order to properl y care for the h igh qual ity furnit ure lacquer .
16 7 Warranty Your A VA LON A COUST ICS loudspeakers ar e w arranted to th e origin al, registered purchaser aga inst defec ts in workmanshi p and materials for a peri od of three years from t he date of first purchase, pro vided th at the enclosed r egistration card is returned to the factory within s even days of the purchas e date.
17 Warranty Statement 1. A VALON A COUSTICS warran ts the materials, workmanship , and proper functioning of thi s product for a period of t hree years to t he origi nal regi stered purchaser, pro vided th at the completed registration card is returned to A VALON A COUSTICS within seven days of the date of pu rchase.
18 6. The above w arrant y is the sole warran ty gi ven by A VA LON A COUS TI CS , and is in lieu of all other warranti es. A ll impl ied wa rranties, including w arranties of merchanta bility or fitn.
19 8 R o o m A c o u s t i c s a n d S p e a k e r P o s i t i o n Introduction The listening room forms the final link of the playback system, as imp ortant as any ot her c omponent in t he chain.
20 An Optical Analogy Let us use a vi sual a nalogy to aid our underst andi ng of acoustic s. I magine that you are in a room that is lit only by a candl e in its center.
21 8.1 Standing Waves The parallel surfaces of most li stenin g rooms can lead t o a potential problem in the low frequencies. A sound wave ca n be repeatedly reflect ed from opposing surfaces, back and forth. If the distance betw een t he surfaces is an integral multiple of one-ha lf the sound wavelen gth, a st anding wave w ill be set up.
22 8.2 Flutter Echo These parallel, reflect ive surfaces can also produce a different audi ble problem. If th ere is l ittle a bsorption at high er frequencies, a m usical transient containin g high frequencies, such as a hand clap or t he strike of a percussion instrument, ca n be heard bouncing repeatedly bet ween the surfaces.
23 8.3 Early Reflections Another sit uation t hat c an reduce t he subject ive qualit y of reprod uced s ound is the presen ce of early reflecti ons. B y earl y reflect ions, w e are ref erring t o reflected sound waves th at reach the listen er with in 10 t o 20 mill iseconds of the direct signa l from the loudspeaker.
24 Avoiding Early Reflecti ons The speed of so und is a pproximat ely one foot (30 cm) per millisecond. Therefore, t o p reserve t he n atural soundstage on your recordings , there should be no reflec.
25 Since the floor i s wit hin 5 feet of the speak er, it is b est to have a carpeted fl oor to absorb floor reflect ions. A t hick, den se carp et and pad will absorb lower frequencies more eff ectively tha n a thin one.
26 8.4 Bass reinforcement By bass rei nforcement , w e mea n t he effect of t he room boundarie s on the propagation of sound. It is widely kn own that speaker placement relative to the floor an d walls ca n affect the relative amount of bas s t hat the system produces.
27 By pr operly select ing the dist ances to eac h surface, we can extend the in - room bass response of th e speaker much deeper t han it s anechoic response. Please see Fig ure 8.5. This i s because t he bass reinforcement provides a boost which i s complement ary to t he bass roll -off t hat w ould be present in an anechoic chamb er.
28 Conversely, improper placement o f the loudspeakers can re sult in une ven frequency re sponse. This results in di minished bass quality. Please refer t o Figure 8.
29 There are typicall y three reflect ive surfaces near eac h speak er: the floor, the rear wa ll, and the side w all. Each of th ese surfaces produces its own reflection, and hence its own cancellation an d reinforcement . By properl y selecting the dist ances t o each surface, we can provide a uniform a nd extended bass response.
30 8.5 Summary of Recommendations Now that we have l ooked at some of the common problems of listening rooms, as well as their cures, let us summarize our findings an d recommendations . Flutter Echo and Standing Waves These situat ions are the result of the r oom having parallel, reflecti ve surfaces .
31 Speaker Placement Although yo ur A VALON A COUST ICS loudspeakers may be placed in a w ide variety of positi ons rel ative to t he walls of the ro om, it is sti ll wise to experiment a bit t o achieve optimal results.
32 8.6 A Listening Room Example In order to make these points more c lear, an example of a room l ayout is given in Figure 8 .9, illustrat ing the prin ciples we have given. Figure 8 .9 - Examp le listening room. The area ar ound th e spea kers is free o f o bjects that would produce ea rly reflect ions.
33 9 Accuracy of Bass Reproduction Introduction We have all ha d the experienc e of list ening to spea kers w ith poor bass quality. Perhaps th e ba ss was muddy, or ill- defined.
34 9.1 Sensitivity to Time-Related Information It is wi dely known t hat the human ear/b rain system is ext remely sensit ive to time-rel ated distortions. This can be understood when one reali zes that directional a nd spatial information is provided by in ter - aural ti me (and phase) differences.
35 9.2 Rationale There i s an old sayin g, " There's no such th ing as a free l unch." There are many trade-offs in spea ker design, as in almost any ar ea one can th ink of.
36 9.3 Measurements of Audio Equipment It should be recognized that mea surements are not th e final arbit er of sound quality of audio comp onents. Oft en ti mes a measuremen t st andard has evolved because i t is easil y perf ormed, or bec ause it is easily rep eatable, or it has shown some lin k to certa in audible characteristics.
37 Loudspeaker Measur ements Returning to loudspeakers , a similar situation has developed. Although nobody listens t o music in an a n echoic chamber, l oudspeaker meas urement s are commonly p erformed in them.
38 Designing for Accur ate Bass Reproduction How, t hen, does one arrive at the goal of a loudspeaker tha t p rovides tonal accuracy in the listeni ng room? The an swer, i n la rge part , comes in t he f orm of th e digi tal computer .
39 9.4 Listening Qualities We have s een how many speaker systems store re sonant bass energy , resulting in ringing and poor transien t accuracy. N ow we w ill turn our attention to the listening experien ce, an d describe how th ese measurable properties correlat e with our subjecti ve impressions.
40 Transient Response E ffects A speaker with poor transient response w ill store energy, rel easing it aft er the initial musical t ransient has passed . This ca uses a loss of det ail and obscures important musical informati on. A l so associated w ith poor t ransient response is a narrow- band resonance, whic h can empha size specific notes.
41 9.5 Important ISIS Recommendations Built as an ident ical p air of transducers, ISI S ret ains one di fference between right and left c hannels that is notew orthy. Very low freq uency bass coupl ing with the room is selecta ble in one of tw o orientations.
42 10 Features Advanced light w eight driver diaphragm materials minimize energy storage and time -domain dist ortion. Each driver in dividually tested and m atched for op timum performance . Smooth, wide polar resp onse for superl ative ima ging capab ilities.
43 11 Specifications Driver Complement 1" Concave Diamond D iaph ragm tweet er 7" Concave Cerami c Midrange 2-13" Nomex-Kevl ar Composit e Woofers All drivers uti lize propriet ary neodymium ma gnetic technologies.
44 12 Notes.
Un point important après l'achat de l'appareil (ou même avant l'achat) est de lire le manuel d'utilisation. Nous devons le faire pour quelques raisons simples:
Si vous n'avez pas encore acheté Avalon Acoustics Isis c'est un bon moment pour vous familiariser avec les données de base sur le produit. Consulter d'abord les pages initiales du manuel d'utilisation, que vous trouverez ci-dessus. Vous devriez y trouver les données techniques les plus importants du Avalon Acoustics Isis - de cette manière, vous pouvez vérifier si l'équipement répond à vos besoins. Explorant les pages suivantes du manuel d'utilisation Avalon Acoustics Isis, vous apprendrez toutes les caractéristiques du produit et des informations sur son fonctionnement. Les informations sur le Avalon Acoustics Isis va certainement vous aider à prendre une décision concernant l'achat.
Dans une situation où vous avez déjà le Avalon Acoustics Isis, mais vous avez pas encore lu le manuel d'utilisation, vous devez le faire pour les raisons décrites ci-dessus,. Vous saurez alors si vous avez correctement utilisé les fonctions disponibles, et si vous avez commis des erreurs qui peuvent réduire la durée de vie du Avalon Acoustics Isis.
Cependant, l'un des rôles les plus importants pour l'utilisateur joués par les manuels d'utilisateur est d'aider à résoudre les problèmes concernant le Avalon Acoustics Isis. Presque toujours, vous y trouverez Troubleshooting, soit les pannes et les défaillances les plus fréquentes de l'apparei Avalon Acoustics Isis ainsi que les instructions sur la façon de les résoudre. Même si vous ne parvenez pas à résoudre le problème, le manuel d‘utilisation va vous montrer le chemin d'une nouvelle procédure – le contact avec le centre de service à la clientèle ou le service le plus proche.
