psi audio brochure

Technical data sheet

PSI A225-M3,M4&M5 / typical characteristics subject to change without prior notice / © RELEC SA.

SWISS MADE BY RELEC SA 1400 YVERDON www.psiaudio.com

[email protected]

“Times have changed.

With more and more audiophiles embracing computer and server-based

audio, their systems are looking

more and more like the “pro” systems used to make recordings.”.

Relec SA électroacoustique rte de Lausanne Z.I. Les Petits-Champs 11A +B 1400 Yverdon-les-Bains VD Switzerland ___________________________________________________________________________________________________________________________________________________________________________________________

______________________________________________________________________________ 21/06/2002 1

CPR Compensated Phase Response System by PSI Audio

Technical description

In a multi-way speaker system, the crossover filters as well as the transducers intro-duce distortion of phase and by consequence of the variations of group delays.

The group delays in low frequencies are more important than in high frequency’s. They provoke a time related separation of the low and high frequencies which then is responsible for the hollow sound of multi-way speaker systems.

In a limited frequency range, an all pass filter allows to intervene on the phase without influencing the amplitude.

The CPR system consists of several all pass filters who each act in a specific range of frequency in order to obtain a wide area of Compensated Phase Response. This then provides a constant group delay.

Thanks to the CPR system the placement of sound in the actual sound space is highly accurate. This technology allows designing of surround sound systems with different types of PSI Audio speakers while maintaining an accurate phase response.

* : Compensated Phase Response system* : Adaptive Output Impedance systemC P R A O I

100 1k- 180

- 90

0

90

180

20k10k20 50 200 500 2k 5k

[ °]

100 1k- 180

- 90

0

90

180

20k10k20 50 200 500 2k 5k

[ °]

f [Hz]

f [Hz]

Phase response

Acoustical pPSI Audio

speaker w

hase response

ith CPR+AOI

Acoustical phase response of a multi way speaker without CPR*


______________________________________________________________________________ 21/06/2002 2

Practical advantage of CPR and impact on stereo application The human ear is very sensitive to group delays or phase irregularities of sounds. The human brain detects such irregularities easily and processes them in to space related information’s like the positioning of a sound source. All traditionally designed speaker systems suffer to a certain degree of such irregularities. These irregularities are the reason why some speakers produce a wider and deeper room perception hence a better-weaker reproduction of the sound image. Such phase irregularities are desirable on creative tools like equalizers, compressors, reverbs and delay units when creating a certain desired sound, whilst being an important part of the creative process of sound engineering. But as the speaker system represents the reference tool of every sound engineer, these irregularities represent a highly disturbing factor and should certainly not be present in the reference tool when trying to design specific sound or its positioning in the sound image. As a sound recording tends go through various processes (recording, mixing and mastering) in which maybe various people, locations and therefore speaker systems will be involved, it may well occur that corrections will be applied, due to phase irregularities, that may not even be present on the actual recording. The PSI Audio speakers feature the unique CPR system that provides a Compensated Phase Response that removes such irregularities and therefore provides a much more accurate reference tool to the sound engineer. The stereo image and the projected room are of an extreme accuracy and therefore provide a more precise working tool. CPR impact on surround sound applications Unfortunately every traditional speaker design has a different phase response and therefore the phase inaccuracy phenomenon tends to get worse in surround sound applications, where the role of room information and positioning becomes an even higher priority and critical part of the sound engineering process. This is one of the reasons why speaker manufacturers strongly recommend using speakers of the same type when creating a surround sound system. The CPR system by PSI Audio will feature an extremely accurate and superior surround sound image and therefore a much improved working environment. One of the big advantages of the CPR system is also that for the first time a user can mix different types of speakers from one manufacturer (PSI Audio) in a surround sound system, whilst maintaining perfectly accurate phase response. Not only will the PSI Audio surround system sound much more accurate and therefore provide a superior working tool, but it can also introduce significant cost and space savings when investing in a new monitoring system.


______________________________________________________________________________ 21/06/2002 1

AOI Adaptive Output Impedance System by PSI Audio Technical description In low frequencies a loudspeaker behaves like a high-pass filter; therefore the damping depends on its mass, on compliances (mechanical and acoustical suspension) and of the source resistance. In high frequencies, the resonances correspond to the deformations of the membranes. The masses in movement are parts of the mobile mass. Compliances depend on the elasticity of the material. The resistances are the internal damping and the source resistance. For an ideal damping in a wide area of frequency, the source impedance must be adapted to every range of frequency for every transducer. The AOI system is constituted by a detection of the movement of the membrane and the moving coil, as well as by a counter reaction filtering. Therefore the damping rate is continuously ideally adjusted according to the frequency. The AOI system allows the reproduction of sound without transducer coloring over the whole frequency range.

0 1.0 2.0 3.0 4.0 5.0 6.0 7.0t [ms]

Acousticaloutput of a multi wayspeaker without CPR*

Electricalinput signal

Impulse behaviour Impulse behaviour

Acousticaloutput PSI Audio

speaker with CPR+AOI

* : Compensated Phase Response system* : Adaptive Output Impedance systemC P R A O I


______________________________________________________________________________ 21/06/2002 2

Practical advantage The PSI Audio speakers featuring the AOI system have much superior impulse behavior to traditional amplifier designs. Whilst the transducer travels to its intended position the AOI circuitry seamlessly adapts the amplifiers output impedance to insure ideal acceleration of the membrane to reproduce the desired impulse. Once the transducer reaches the end of the impulse the AOI circuitry provides a break in order to act against an overshooting of the transducer. The AOI circuitry is almost capable of reproducing a square wave and therefore increases accuracy by marring the transducer and the amplifier in to a perfect couple. A nice side effect of the AOI system is that the membranes of a PSI speaker do not produce parasite sounds when other speaker systems in the room are in use. When air pressure is produced by other sources than the PSI speakers the AOI will detect this and tighten the damping of its transducers in order not to produce parasite sounds not originating by the speaker system in use. In today’s times where much more importance is given to the low end reproduction of sounds especially when using sub woofer technology in surround sound systems the importance of a monitoring system that has an accurate and not a flattering reproduction becomes essential. The result of the AOI featured PSI Audio speaker range is a speaker family with a highly accurate impulse behavior with a minimum of transducer coloration.

1=Gnd2=Hot3=Cold

Hi. ± V Low ± 18V

MAINS TRANSF. RECT. REG.

LIMITER

TEMP. SENS

STANDBY

INPUT

LIMIT / STANDBY

POWER

PSC*

*PSC : Phantom Standby Control :

C* >= 10uF

R <= 22KOhms

(1)

(2)

(3)

Electronic Balanced output

CONNECT ONLY TO:True Balanced XLR INPUT With PSC*

(1)

(2)

(3)

+ 5 to 25V DC

Copier coller dans Word 2007:accueil, collage spécial, image métafichierBouton droite, modifier l’image

ON=>STANDBY

PSC Command principle

Command principle schematic

The front panel LED is slightly lit in red during the standing mode.

Relec SAElectroacoustiqueZ.I. Les Petits-Champs 11A +B1400 Yverdon-les-Bains VDSwitzerland

PSI technology documents, typical characteristics subject to change without prior notice / © RELEC SA.More info: www.psiaudio.com

PSC enables to control the standby mode of your loudspeakers through the signal cable. This command is generated by pulling up simultaneously the voltage of the entries (2) and (3) of the XLR. A voltage of +5 to 25V DC referenced to the ground is necessary to control the standby mode.

*This schematic is only applicable for gears equiped with serial capacitors. Other more elegantsolutions are also easily applicable.

A14-MOur Entry-Level model

PSI A14-M8 / typical characteristics subject to change without prior notice / © RELEC SA.

SWISS MADE BY RELEC SA 1400 YVERDON

A14-M www.psiaudio.com

[email protected]

The A14-M full range speaker is the smallest member of the PSI Audio A-Series professional studio monitor range. Housed in an extremely compact cabinet the A14-M is designed to implement highest possible SPL and broad bandwidth. The A14-M is ideal for studio application where the ultimate in precision and portability is required. Packed into its compact dimensions, is all the technology of its larger brothers.The powerful bi-amplified output features the unique “AOI” output stages, while the active crossover, with integrated “CPR”, delivers unprecedented impulse behavior – with excellent stereo imaging. The crossover is also optimized for maximum phase coherence, projecting a wide horizontal and vertical ideal listening area.Designed to work in harmony with the full range of A series monitors the A14-M also makes ideal rear speakers in a surround sound setup, or can be developed in to a more powerful system by adding the A225-M sub – thus protecting your investment.

Description

Typical characteristics - all rights reserved. All data subject to change without prior notice.

A 14-M

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

0

-10

-20

-30

[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90

-10dB Roll OffSPL@1m Active A14-M

ACOUSTIC PHASE Active A14-M

Max Continuous SPL 1m A14-M

70+30 W

100 W

101 dB (single)

112 dB (pair)

56 - 22000 Hz

±2.5 dB (65Hz - 18kHz)

±45° (260Hz - 16kHz)

100° x 100° (H x V)

3.5 kHz

Ø 147 mm / Ø 104 mm

Ø 70 mm / Ø 20 mm

163 x 243 x 170

5.5 Kg

Features

Technical Data

*Further information: www.psiaudio.com

Metal handle for easy handling and for mic. stand or installation.

Volume control on the front panel.

Protection circuits with overload indicator.

Designed for stereo and multichannel monitoring.

Magnetically shielded for use close to video monitors.

Optimised directivity by phase coherency.

Flat frequency response.

Real balanced input.

Orininal Technologies* : CPR, AOI, PSC, ALG.

Power RMS

Program power

Continuous Max SPL, 1m

Program Max SPL, 1m

Response at -6dB

Tolerances

Phase tolerances

Dispersion

(P.N. 4 - 16 kHz) at -6 dB

Crossover frequency

Woofer's dim.

Ext. / Diaphragm

Tweeter's dim.

Ext. / Diaphragm

Dimensions

cabinet W x H x D mm

Net Weight

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

90

-10

-20

-30

[Q]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

10

5

2

1

[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90

-10dB Roll OffSPL@1m A14-M


Directivity Factor A14-2M

ACOUSTIC PHASE A14-M

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

-20

-30

-40

-50

-60

THD@-10dBu/1m A14-M

CP

R*

1=Gnd2=Hot3=Cold

115/220V Hi. ± 45V Low ± 18V

MAINS ON/OFF FUSE TRANSF. RECT. REG.

LIMITERLEVEL ROLL OFF HP LP

TEMP. SENS

*C P R : Compensated Phase Response system.*A O I : Adaptive Output Impedance system.*PSC : Phantom Standby Control (on Master series).

HP

LP

STANDBY

INPUT

POWER

AOI*

LIMIT

POWER

POWER

AOI*

PSC*


All mesurement in anechoic roomacoustical axis at 1 meter

temperature 23 °C humidity 50

±2±20%

Puissance RMS

Power RMS70+30 W

Puissance programme

Program power100 W

Impédance d'entrée

Input ImpedanceSym, 10k Ohms

Sensibilité pour 100 dB @ 1m

Sensivity for 100 dB @ 1m0.775 V

Rapport signal sur Bruit

Signal to Noise Ratio-96 dBA

Saturation d'entrée

Input Overload24 Vpp

Niveau max. continu, 1m

Continuous Max SPL, 1m101 dB (single)

Niveau max. programme, 1m

Program Max SPL, 1m112 dB (pair)

Réponse à -6 dB

Response at -6dB56 - 22000 Hz

Tolérances

Tolerances±2.5 dB (65Hz - 18kHz)

Distorsions THD

Distortion THD< 1.8% (95Hz-15kHz)

Phase tolérances

Phase tolerances±45° (260Hz - 16kHz)

Dispersion (B.R. 4 - 16 kHz) à -6 dB

Dispersion (P.N. 4 - 16 kHz) at -6 dB100° x 100° (H x V)

Système

System2 Way(s)

Fréquence de coupure

Crossover frequency3.5 kHz

Dim. basses Ext. / Membrane

Woofer's dim. Ext. / DiaphragmØ 147 mm / Ø 104 mm

Dim. aigues Ext. / Membrane

Tweeter's dim. Ext. / DiaphragmØ 70 mm / Ø 20 mm

Connecteurs

Connectors1 x XLR F / 3P

Signal entrée

Signal input 1=GND, 2=(+), 3=(-)

Matériaux du boîtier

Box MaterialMDF

Dimensions boîtier L x H x P mm

Dimensions cabinet W x H x D mm163 x 243 x 170

Poids brut / net

Gross / Net Weight6.2 / 5.5 Kg

Tension de secteur

Voltage115/230V (50-60Hz)

Consommation

Consumption Standby-Quiescent-Max1.4 - 6 - 100 W

Humidité Moy / Max

Mean / Max Humidity< 75% / < 90%

Température externe

External Temperature5 - 40 °C



A14-Mwww.psiaudio.com

[email protected]

80

150

163

121

85

243

17070

Large anechoical roomTemperature 23 °C Humidity 50

±2±20%

Acoustical axis:

Measurement environment:

Mounting:

All dimensions are in mm

Bottom view Side view

Front view

Min

imum

well-

aired s

pace

Front

Fro

nt

1 x UNC 3/8’’like mic stand




[email protected]

88 April 2009Professional audio Musik & Equipment

TEST | NAHFELD-MONITOR | PSI Audio A 14-M

SchlagschattenVon Michael Nötges

Bereits der Test des Nahfeldmonitors A 17-M (Ausgabe 1/2009) sorgte für

Begeisterung in der Redaktion von Pro-fessional audio. Die Lautsprecher zeig-ten sich in Bestform und sammelten nicht zuletzt aufgrund ihrer hohen Im-puls- und Signaltreue fl eißig Sympathie-punkte. Grund genug, mit dem A 14-M auch dem kleinsten Ableger der hierzu-lande noch eher unbekannten Schweizer Lautsprechermanufaktur PSI Audio auf

den Zahn zu fühlen. Kennern ist Alain Roux, Inhaber und Unternehmensgrün-der der Firma Relec Sa, zu der auch PSI Audio gehört, bereits seit Mitte der 1970er-Jahre ein Begriff. 1975 entwickel-te der Schweizer die ersten Lautsprecher und gehört heute in Fachkreisen zu den anerkannten Monitor-Spezialisten. Die Maxime von PSI Audio ist damals wie heute, das Optimum an klanglicher Prä-zision zu erreichen.

Das gilt auch für den kleinsten PSI-Monitor, den A 14-M. Obwohl er mit ei-

Auch kleine Nahfeldmonitore

wie der A 14-M des Schweizer Lautsprecher-

spezialisten PSI Audio

schlagen mitunter große Schatten,

in denen sich manch massiger

Konkurrent – schneller als ihm lieb ist –

wiederfindet.

TEST || NAHFELD MONITOR || PSI Audio A 14 M

ssc

� Klangliche Neutralität und tonale Ausgewogenheit

� Sehr gutes Impulsverhalten und präzise Signaltrennung

� Clevere, multifunktionale Bügelkonstruktion

–

Summary

Der A 14-M von PSI Audio entpuppt sich als präziser Kompakt-Monitor, der klanglich nicht auffällt und damit beste Vorausset-zungen zum professionellen Arbeiten bietet.

Musik&Equipment

PSI Audio A 14-M

� �

––

��

Schlagschatten

nem Stückpreis von rund 740 Euro knapp 400 Euro günstiger ist, als sein großer Bruder, der A 17-M, hat der Hersteller kei-nesfalls an der PSI-typischen technischen Finesse gespart und ihm sowohl das proprietäre CPR-System (Compensated Phase Response) zur analogen und frequenzabhängigen Pha-senkorrektur mittels mehrerer All-Pass-Filter, als auch das AOI-System (Adaptive Output Impedance) für definiertes Ein-und Ausschwingverhalten der Membranen spendiert. Stark vereinfacht gesagt, überwacht die analoge AOI-Schaltung die Membranbewegung, analysiert sie und passt anhand der ge-wonnen Werte den Dämpfungsfaktor der Endstufen dyna-misch an den Frequenzgang an. Das Ergebnis der beiden PSI-Spezialitäten sei eine deutlich verbesserte Detailauflösung, bessere Stereoabbildung, Ortungsschärfe und Tiefenstaffe-lung sowie ein optimiertes Impulsverhalten.

Impulsiver AlpenzwergImpulsiver Alpenzwerg

Beim A 14-M handelt es sich, wie bei allen PSI-Monitoren, um einen aktiven Zweiwege-Bassreflex-Lautsprecher. Allerdings ist das Nesthäkchen bei einem Gewicht von insgesamt 6,2 Ki-logramm kaum höher als ein DinA5-Blatt und eignet sich auf-grund seiner kompakten Bauweise besonders für platzkarge Abhörsituationen in Ü-Wagen sowie Surround-Setups oder als edler Desktop-Lautsprecher. Der kompakte Nahfeldmonitor ist mit einer aktive Frequenzweiche – die Übergangsfrequenz liegt bei 3,5 Kilohertz – und zwei Endstufen bestückt, die für den Hoch- sowie Tiefmitteltöner 30 beziehungsweise 70 Watt an Dauerleistung bereitstellen.

Das kompakte Gehäuse aus MDF ist mit weinrotem Lack überzogen, wobei der dezente Metallic-Look das etwas nüch-terne Äußere geschmackvoll aufwertet. Die Gehäusefertigung hat PSI Audio nach Sainte-Croix, einer kleinen Gemeinde im Juragebirge, verlagert. Entwicklung, Montage und das elekt-ronische Design finden im Hauptquartier in Yverdon statt. Zur Installation des A 14-M ist ein Montagebügel an den Seiten des Gehäuses verschraubt. Weist er nach oben, dient er der hängenden Installation, klappt man ihn unter den Gehäuse-boden, bestimmt er den Neigungswinkel zur Aufstellung der Monitore auf Meter-Bridge oder Desktop – eine einfache wie gleichzeitig clevere und praxisnahe Lösung.

Der Kalottenhochtöner des A 14-M stammt vom französi-schen Hersteller AAC. Damit schlägt der Kleine von PSI Audio etwas aus der Art. Ansonsten setzt der Hersteller auf selbst-entwickelte Spezialanfertigungen, die von der taiwanesischen Firma Ly Yuan Electronics gefertigt werden. Der Referenzmo-nitor A 25-M ist sogar mit handgefertigten und penibel opti-mierten Hochtönern aus eigenem Hause bestückt. Anyway, die Gewebekalotte des Hochtöners sitzt jedenfalls hinter ei-nem Schaumstoffschutz verborgen, inmitten des schallführen-den Wave Guides. Ein robustes Schutzgitter bewahrt die Ge-webemembran des Tiefmitteltöners vor versehentlichen Be-schädigungen im mobilen Einsatz. Die Bassreflexöffnung befindet sich als schmaler Spalt auf der Vorderseite, was für eine wandnahe Aufstellung ohne klangliche Verfälschungen von Vorteil ist. Von Vorteil ist in solchen Fällen außerdem der von vorne erreichbare Regler zur stufenlose Anpassung der Eingangsempfindlichkeit (-∞ bis 0 dBu), der ansonsten nach der Installation nicht mehr erreichbar wäre. Eine grüne LED informiert über die Betriebsbereitschaft. Bei drohender Über-lastung der Elektronik blinkt selbige zunächst rot und signali-siert damit den Einsatz des integrierten Limiters. Leuchtet sie durchgängig rot, gilt es die Eingangsempfindlichkeit zu senken. Die Elektronik ist überlastet.

Auf der Rückseite finden sich lediglich der XLR-Eingang, sowie ein Trim-Poti zur fließenden Kalibrierung des Roll-Off-

90 April 2009Professional audio Musik & Equipment

TEST | NAHFELD-MONITOR | PSI Audio A 14-M

Filters. Dieser dient zur Absenkung des Bassbereichs unterhalb 100 Hertz um maximal 10 Dezibel. Wichtig ist der Roll-Off zur optimalen Anpassung des Sys-tems an einen Subwoofer, oder um den Tieftonbereich an den Raum anzupas-sen, wenn die Monitore direkt an einer Wand oder in einer Ecke platziert sind.

Präzises Kompakt-WerkzeugIm Hör und Praxistest von Professional audio erweist sich der A 14-M als wirkli-ches Schätzchen. Zunächst lernen wir

den praktischen Bügel zu schätzen, der sowohl bei der Desktop- als auch erhöh-ter Sockel-Aufstellung die Monitore opti-mal ausrichtet. Dann freuen wir uns über die Möglichkeit die Eingangsempfi nd-lichkeit anzupassen, ohne hinter das Ge-häuse greifen zu müssen. Somit ist in un-serem Fall eine schnelle und präzise Pe-gelanpassung zu den zum Vergleich angeschlossenen Focal CMS 50 (3/2009) möglich.

Erster Eindruck: Der A 14-M ist klang-lich unauffällig. Das ist keineswegs nega-tiv zu verstehen, denn er überzeugt un-mittelbar durch sein ausgewogenes Klangbild, das keinerlei tonale Verfäl-schungen aufweist. Schönfärberei liegt dem Schweizer völlig fern, vielmehr er-füllt er nüchtern und präzise seinen Job. Im Gegensatz zum CMS 50 wirkt er be-sonders im unteren Mittenbereich etwas schlanker und im Bass-Bereich behält er seine akkurate Wiedergabe selbst bei hö-heren Abhörpegeln bei. Dass der kleine Schweizer bei Frequenzen unterhalb 100 Hertz (siehe Frequenzgang) an seine Grenzen stößt, kann ihm beim besten Willen nicht vorgehalten werden. Für ein wirkliches Full-Range-System empfi ehlt sich daher ganz einfach der passende Subwoofer wie beispielsweise der A 225-M von PSI Audio. Aber auch ohne, weiß der A 14-M zu gefallen. Vor allem sein sehr gutes Impulsverhalten und die breit-bandige Aufl ösung führen zu präziser Stereoabbildung mit sehr guter Ortungs-schärfe. Sowohl die Phantommitte, und zwar ganz unabhängig vom vorliegenden Programmmaterial, als auch die einzel-nen Instrumente sind zielsicher auszu-machen und führen zu einer sehr gelun-gen Raumdarstellung und exakter Tie-fenstaffelung. Dabei erweist sich der unauffällige Charakter als echte Stärke, treten die Monitore in den Hintergrund, sodass sich der Klang – vorausgesetzt der Sweetspot wird nicht verlassen – von den Lautsprechern löst. Unauffällig heißt auch, dass sich der A 14-M als neutrales Werkzeug entpuppt, das sich beim Test-Mischen eines Tracks zur Aufdeckung von Schönheitsfehlern, zur Anpassung

von Hallräumen und für Effekteinstellun-gen empfi ehlt. Die genaue Positionierung der Instrumente im Stereopanorama ge-lingt ohne Probleme und die Gegenprobe mit den KRK Exposé 8 (Ausgabe 8/2007) beweist, dass sich unterm Strich vorzüg-lich mit dem A 14-M arbeiten lässt.

FAZIT: Der A 14-M ist im besten Sinn ein unauffälliger Nahfeldmonitor. Klanglich ausgewogen, mit hoher Detailaufl ösung, sehr gutem Impulsverhalten und präzi-ser Ortungsschärfe, entpuppt sich der Alpenzwerg als nüchternes Abhör-Werk-zeug, das sich besonders für Surround-Setups, Ü-Wagen oder beengte Stu-dioumgebungen empfi ehlt. Rund 730 Euro pro Stück ist ein stolzer aber auf-grund des hohen Qualitätsniveaus durch-aus fairer Preis. �

Das Roll-Off-Filter ermöglicht zum einen die Anpassung des A 14-M an die akustischen Abhörbedingungen, zum anderen zur optimalen Anbindung eines Subwoofers.

Der Frequenzgang des A 14-M ist für einen Kompakt-Monitor vorbildlich. Für ein wirkliches Full-Range-System empfi ehlt sich der Einsatz eines Subwoofers, um auch Frequenzen unterhalb 100 Hertz optimal wiederzugeben.

SteckbriefModell A 14-M

Hersteller PSI AudioVertrieb Synthax GmbH

Am Pfanderling 6085778 HaimhausenTel.: 08133 913810Fax: 08133 [email protected]

Typ Zweiwege-Aktiv-Bassrefl ex-Lautsprecher

Abmessungen BxTxH [mm]

163 x 170 x 243

Gewicht [kg] 6,2Preis [UVP, Euro] 738Ausstattung

Lautsprecher 2Ø Bassmembran 1 [mm] 104Ø Hochtönermembran [mm]

24

Ausgangsleistung Tieftonkanal 1 und 2 [Watt]

70

Ausgangsleistung Hochtonkanal [Watt]

30

Regelmöglichkeiten

Lautstärke/Eingang-sempfi ndlichkeit

stufenlos regelbar: -∞ bis Referenz-Pegel 0 dBu)

ROLL OFF Bass-Absenkung (stufenlos, maximal -10 dB)

Ein- und Ausgänge

Eingänge 1 x symmetrisch XLRZubehör

Handbuch, NetzkabelBesonderheiten

Überlastungsschaltung, AOI- und CPR-System und PSC

Bewertung

Verarbeitung sehr gutAusstattung gutBedienung sehr gutMesswerte sehr gutKlang gut bis sehr gutGesamtnote Oberklasse gut bis sehr gutPreis/Leistung gut bis sehr gut

PSI A21-M3 & M4 / typical characteristics subject to change without prior notice / © RELEC SA.



[email protected]

A17-M

Our entry(next)level

Your Next-Level model

A classic near-field precision monitor, the A17-M is the ideal entry model to the PSI Audio range. Perfectly suited for surround sound and near-field applications, the A17-M is ideal for studio application where the ultimate in precision is required. Its compact form incorporates the full range of PSI Audio’s outstanding technologies. The powerful bi-amplified output features the unique “AOI” output stages, while the active crossover, with integrated “CPR”, delivers unprecedented impulse behavior – with excellent stereo imaging. The crossover is also optimized for maximum phase coherence, projecting a wide horizontal and vertical ideal listening area. Designed to work in harmony with the full range of A series monitors the A17-M also makes ideal rear speakers in a surround sound setup, or can be developed in to a more powerful system by adding the A225-M sub – thus protecting your investment.

Description


A 17-M

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

0

-10

-20

-30


[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90


20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90


90° x 90° (H x V)

80+40 W

120 W

104 dB (single)

115 dB (pair)

44 - 23000 Hz

±2.5 dB (50Hz - 20kHz)

±45° (150Hz - 20kHz)

3.6 kHz

Ø175 mm / Ø130 mm

Ø 100 mm / Ø 25 mm

200 x 320 x 230

8.4 Kg

Features

Technical Data

Very large bandwidth in a compact cabinet.




Very high SPL in a compact cabinet.




Orininal Technologies* : CPR, AOI, ALG, PSC.


Power RMS

Program power


Program Max SPL, 1m

Response at -6dB

Tolerances

Phase tolerancesDispersion

(P.N. 4 - 16 kHz) at -6 dB

Crossover frequency

Woofer's dim.

Ext. / Diaphragm

Tweeter's dim.

Ext. / Diaphragm

Dimensions


Net Weight

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

90

-10

-20

-30

[Q]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

10

5

2

1

[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

-20

-30

-40

-50

-60

-10dB Roll Off


THD@-10dBu/1m A17-M


Directivity Factor A17-M

SPL@-10dBu/1m A17-M

CP

R*

1=Gnd2=Hot3=Cold

115/220V Hi. ± 45V Low ± 18V



TEMP. SENS


HP

LP

STANDBY

INPUT

POWER

AOI*

LIMIT

POWER

POWER

AOI*

PSC*


Puissance RMS

Power RMS80+40 W

Puissance programme

Program power120 W













Réponse à -6 dB


Tolérances

Tolerances±2.5 dB (50Hz - 20kHz)

Distorsions THD


Phase tolérances




Système

System2 Way(s)




Woofer's dim. Ext. / DiaphragmØ 175 mm / Ø130 mm



Connecteurs


Signal entrée



Box MaterialMDF



Poids brut / net


Tension de secteur


Consommation


Humidité Moy / Max







[email protected]

140

135

16

0

Front

Fro

nt

100

Gravity center 3

20

230200 70

Min

imum

well-

aired s

pace

Panel screwing area depth 16mm

19

0

100

65

30

30 30

All dimensions are in mm


Front view

Acoustical axis

Mounting


Large anechoical room Temperature 23 °C Humidity 50

±2 ±20%




[email protected]

PSI A21-M3 & M4 / typical characteristics subject to change without prior notice / © RELEC SA.



[email protected]

A21-M The 2-way

Reference Model

The A21-M high power near / mid-field precision monitor covers a broad frequency spectrum, allowing the user to be in full control of their audio production. Its unique and highly optimised assets make it perfect for near, mid-field and surround sound applications where ultimate precision is required. The powerful bi-amplified output stages features the unique “AOI” output stages and has a protection circuit, which can be monitored via the red LED on the front panel. The active crossover, with integrated “CPR”, gives the A21-M unprecedented impulse behavior – with excellent stereo imaging. The crossover is also optimized for maximum phase coherence, projecting a wide horizontal and vertical ideal listening area. The electronics are housed in a unit mechanically isolated from the speaker cabinet to avoid resonance at high sound pressure levels.Designed to work in harmony with the full range of A series monitors the A21-M also makes ideal front speakers in a surround sound setup, or can be developed in to a more powerful system by adding the A225-M sub – thus protecting your investment.

Description


A 21-M

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

0

-10

-20

-30


20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90


[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90


Features

Technical Data

Very high SPL in a compact cabinet.

Compatible with industry standard mouting systems.







Amplifier unit acoustically uncoupled from speaker cabinet.

Orininal Technologies* : CPR, AOI, ALG, PSC.


Power RMS

Program power


Program Max SPL, 1m

Response at -6dB

Tolerances

Phase tolerances

Dispersion

(P.N. 4 - 16 kHz) at -6 dB

Crossover frequency

Woofer's dim.

Ext. / Diaphragm

Tweeter's dim.

Ext. / Diaphragm

Dimensions


Net Weight

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

90

-10

-20

-30

[Q]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

10

5

2

1

[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

-20

-30

-40

-50

-60

THD@-10dBu/1m A21-M



Directivity Factor A21-M

SPL@-10dBu/1m A21-M -10dB Roll Off

CP

R*

1=Gnd2=Hot3=Cold

115/220V Hi. ± 45V Low ± 18V



TEMP. SENS


HP

LP

STANDBY

INPUT

POWER

AOI*

LIMIT

POWER

POWER

AOI*

PSC*


Puissance RMS

Power RMS120+50 W

Puissance programme

Program power170 W













Réponse à -6 dB


Tolérances

Tolerances±2 dB (44Hz - 20kHz)

Distorsions THD


Phase tolérances




Système

System2 Way(s)




Woofer's dim. Ext. / DiaphragmØ 217 mm / Ø 170 mm



Connecteurs


Signal entrée



Box MaterialMDF



Poids brut / net


Tension de secteur


Consommation


Humidité Moy / Max




PSI A21- / typical characteristics subject to change without prior notice / © RELEC SA.M3 & M4



[email protected]

90

175 4 x M6

200

Front

Fro

nt

150

Gravitycenter

400

300250 70M

inim

um

well-

aired s

pace

(Omnimount®) (120 series)

50

255

125

All dimensions are in mmAll dimensions are in mm


Front view

Acoustical axis

Mounting

PSI A21- / typical characteristics subject to change without prior notice / © RELEC SA.M3 & M4


±2±20%




[email protected]

PSI Audio A17M & A21M Active Monitors Reviews : Monitors

These compact monitors from Swiss company PSI incorporate some very clever technology, including ‘Class-G’ amplification, that helps put them in

a class of their own!

SI Audio is almost certainly an unfamiliar name to most, yet I predict these intriguing Swiss monitor-speaker manufacturers will quickly

become as well known and highly thought-of as the many

well-established high-end manufacturers, such is the quality of their products.

PSI Audio started out as Relec SA in the late 1970s, the brainchild of Alain

Roux, and have been producing a broad range of hi-fi, PA and studio

monitoring loudspeakers for over 30 years, both under their own name and as

OEM manufacturers. However, the PSI Audio brand is now being marketed

more actively worldwide, and the company’s innovative products are being

brought to the attention of a far wider audience.

PSI Audio’s production facilities are split across two sites. The speaker cabinets are made in St Croix,

a small town in the Swiss Jura mountains with a strong history in the craft of making fine musical instruments and lavish music boxes, since the 19th century. Product development, electronics design, manufacture and

assembly are performed at Yverdon alongside Lake Neuchâtel. This facility, built in 1989, accommodates a 150-cubic-metre anechoic chamber, seven metres high and incorporating four tons of isolation material,

which is employed in the testing and development of PSI’s loudspeaker designs.

Technology Overview

Like most manufacturers, PSI Audio claim to use several unique technologies in their speaker designs, each

with a catchy name. In this case the relevant ones are AOI, CPR, PSC and Class G.

The first stands for Adaptive Output Impedance: the ability of the power amplifiers to adjust their output

impedance to optimise the impulse behaviour and damping of the connected drive units. In essence, the

circuitry determines the movement of the speaker diaphragm by analysing the current flow between amplifier

and driver, and then adjusts the impedance as necessary to control that movement, maintaining as closely as

possible a near-ideal impulse response. So as the transducer travels to its intended position, the AOI circuitry

maximises current flow to provide the best diaphragm acceleration to reproduce the transient impulse as

accurately as possible. Once the transducer reaches the end of the impulse, the AOI circuitry then acts to

provide an active brake, minimising diaphragm overshoot. PSI Audio claim that this technology makes their

system “almost capable of reproducing a square wave”, and that the system is sensitive enough to detect

parasitic driver resonance if other loudspeakers are being used in the room, and will damp it out automatically!

The result is extremely low coloration and an impressively tight transient behaviour, even at low frequencies

and despite using a ported-cabinet design.

CPR, or Compensated Phase Response, is a technology that corrects the additive phase shifts and group delays inherent in conventional crossover filters and mechanical transducers. It achieves this with carefully

designed all-pass filter stages, and the result is a remarkably precise stereo image and an accurate sense of space in the recording environment.

PSC stands for Phantom Standby Control, and is a simple system to enable remote on/off switching. When a voltage of between 5 and 25 V is applied via 22kΩ resistors to both lines of the balanced audio input

(relative to the cable screen), the speaker is forced into a standby state. In most cases, large-value

DC-blocking capacitors will be required, to protect the output of the monitoring controller (or other audio

source) from the DC control voltage. Presumably some users will find this a useful facility, but DC blocking capacitors are known to be a source of low-level signal distortion, and the switch sensing — although the only

practical arrangement given the use of a phantom system on the audio connection — seems inverted. Most

remote switching systems use an external voltage to switch the speakers on, not off! Suffice to say I made no use of this option.

Published in SOS July 2011

: Close windowPrint article

Hugh Robjohns

P

Technology Overview

PSI A-Series Monitors

Listening

Conclusion

Alternatives

Class-G Amplification

PSI A17M & A21M £2599/£4169

pros

Stunning performance. Compact size. Pin-sharp stereo imaging and a wide sweet spot. Remarkably tight low-frequency control and bass extension. Efficient, cool-running power amplifiers. Unusual but attractive red colour scheme. Closely matched tonality across different models.

cons

Scarily expensive.

summary

Small- and medium-sized two-way active monitors capable of delivering exceptional accuracy and neutrality, with remarkable LF control and extension, and precise stereo imaging.

information

A17M £2598.85 (pair), A21M £4169.38 (pair). Prices include VAT.

eMerging UK +44 (0)20 8941 6547.

Click here to email

www.emerginguk.com

www.psiaudio.com

In this article:

Sound On Sound : Est. 1985

Finally, Class G is an unusual amplifier topology that aims to achieve a power efficiency approaching that of Class-D ‘switching’ amps, while maintaining the linearity of Class-AB amplifiers. The ‘Class-G Amplification’ box on the next page explains the concept in more detail.

PSI A-Series Monitors

For this review I was supplied with two pairs of two-way, active PSI Audio

monitors: the diminutive A17M model, which employs an approximately

six-inch bass/mid-range driver, and the larger A21M, with about an eight-inch

unit.

Both models share the same one-inch tweeter, the same basic cabinet

construction, and the same amplifier chassis configuration. There is a smaller model in the range (the A14M), as well as a larger three-way system (A25M),

a centre-channel model with a bass/mid driver on either side of the tweeter

(A214M), a dedicated subwoofer (A225M), and a floor-standing model (the

A215M) in a similar configuration to the A214M.

All models employ unusual but attractive burgundy paint-finished MDF

cabinets with a horizontal, slotted port vent across the bottom of the front baffle, below the bass/mid driver. A metallic-black cabinet finish is available

on special order, but at greater cost.

The dimension and weight of the smaller A17M model are 320 x 200

x 230mm (HWD) and 8.4kg, while the larger A25M measures 400 x 250 x 300mm (HWD) and weighs 13.4kg.

Specifications for the desktop-sized A17M give a programme-peak SPL of

an impressive 115dB per pair at one metre. Frequency response is quoted as

44Hz to 23kHz at the -6dB points, a figure that narrows to 50Hz to 20kHz ±2.5dB. The crossover frequency is

3.6kHz, and the amplifiers supply 80W and 40W for the bass/mid driver and tweeter, respectively. The larger

A25M is quoted as managing 119dB SPL for programme peaks (per pair again), and a response of 32Hz to 23kHz at the -6dB points or 38Hz to 20kHz ±1.5dB. The crossover is also lower, at 2.4kHz, and the amplifiers

are up-rated to 120W and 50W. Both models feature an electronically balanced input with an impedance of

10kΩ, and a nominal sensitivity of 0dBu for 100dB SPL at one metre.

The tweeter is set at the bottom of an unusually deep waveguide machined into the front baffle, and is

consequently very well protected from accidental damage. This restricts the HF dispersion above about 4kHz

to roughly 90 degrees in both the horizontal and vertical planes, which will help to minimise unwanted

reflections from mixing consoles, computer workstations and side walls — no doubt contributing to the

excellent stereo imaging. A front-panel LED illuminates green when the speaker is powered, and red when in

standby mode, or when the heat- or volume-protection circuitry is operating.

The rear panel is metal and acts as a cooling heatsink for the amplifiers. It also carries just three controls: a mains on-off rocker switch, and rotary controls for level and LF roll-off. An IEC mains inlet incorporates a fuse and voltage selector, and both models employ a linear power supply with a substantial toroid mains transformer.

The input level control spans a 20dB range, maximum sensitivity being 0dBu for 100dB SPL at one metre, while the bass attenuation control covers a 10dB range, starting from about 200Hz in the A21M and 250Hz in the A17M. This control is intended to correct for the boundary effect bass-boost when the speaker is placed

close to room walls or corners. My review was conducted with the speakers in a free-field situation, with the

bass control set to its 0dB calibrate position, but the handbook recommends settings of -4dB for a half-space

(near a back wall) situation and -7dB for a quarter space (corner) placement. These settings are less than the theoretical -6 and -12dB figures, and clearly there is room for experimentation and personal preferences in

finalising the calibration. When the partnering A225M dual subwoofer is being used with either the A21M or

A17M, the handbook recommends setting the bass roll-off to its maximum attenuation to optimise the

integration and power handling.

Listening

I did much of my auditioning with the speakers mounted well away from side

and rear walls, and driven from a Grace M902B monitor controller. From the outset it was clear that both the A17M and A21M were something special, and

frequent direct comparison with my reference PMC three-way IB1s quickly

confirmed that fact! The level of performance was immediately and obviously

far higher than that of the vast majority of similarly sized monitors. Moreover,

the tonal matching between the two models was extremely close, which is

always a sign of meticulous design and attention to detail.

Both models exhibited a bass extension and power handling that belied their modest cabinet sizes, and both exhibited remarkable transient behaviour and

control, with pin-sharp stereo imaging. Tonally, these speakers are extremely

neutral and accurate — voiced along the lines of classic British monitors from

Both of the monitors under review feature the same rear-panel controls, including knobs for input sensitivity and low-frequency response.

The amplifier PCB. On the right is the toroidal mains transformer, while to the left, you can see the diodes used to control the output stages’

ATC, PMC and Harbeth — and completely free from the upper mid-range

presence hype that is so often used to convey a (false) impression of detail and resolution.

Instead, these speakers provide real detail and superb resolution across the bandwidth, and do so without

any sense of fatigue even after hours of critical listening. The top end is gloriously smooth and natural, yet

wonderfully revealing and precise. The mid range enjoys negligible levels of the harmonic distortion that so

often masks the mid-range clarity in inferior designs. Indeed, the mids come across as totally uncoloured, and

both monitors passed my very critical spoken-voice tests with ease, delivering complete naturalness and

accurate spectral balances without any hint of boominess, boxiness or sibilance. Moving down to the bottom

end, the bass control — the ability to stop and start bass notes and separate bass guitars from kick drums —

was remarkable, delivering a performance more associated with sealed-cabinet designs rather than ported

construction. Bass extension was also impressive, particularly for the very compact A17M.

Simple crossed-pair stereo recordings were portrayed with immensely precise stereo imaging that remained

surprisingly stable across a wide listening area, and I was left in no doubt at all as to the absolute position when panning instruments across the soundstage. It sounds like a basic requirement — and it is — but it’s surprising

how many speakers present vague or blurred imaging. Room acoustics and reverberation filled the space

between the speakers very linearly and naturally, and with a good sense of depth when auditioning appropriate material.

Dynamics were reproduced naturally, with superb transient punch and clarity, and without any hint of monitor

compression, even at silly listening levels. In fact, these speakers seem very comfortable working at levels that

few similarly sized speakers would be able to cope with — and given the very low levels of coloration you will

find yourself listening at much louder levels than you think you are if you’re not careful!

Working on a mix with these monitors was a joy, making compression and equalisation decisions very intuitive and natural, simply because you can hear what you’re doing so easily. Flaws in recorded tracks are

obvious; over-compressed commercial music and low-rate MP3s are exquisitely unpleasant to audition, just as

they should be!

Conclusion

Reviewing monitor loudspeakers is always a challenge. The technology involved in the vast majority of cases is very mature and with few significant variations. Consequently, the vast majority of monitors perform adequately

and comparably to their peers at any given price level. Very few are unusably poor, but equally, very few stand

out as exceptionally good. In fact, I can count those models I have reviewed that I would suggest fall into the ‘outstanding’ category on the fingers of one hand. My list would include PMC’s AML1 (September 2001),

Earthworks’ Sigma 6.2 (April 2003), and K+H’s O300 (October 2004), with honourable mentions going to

Acoustic Energy’s AE22 (May 2008) and, although I didn’t review it, Event’s Opal (August 2009).

However, the time has now come to introduce my second hand to the count, because I have to add a new contender for the honour: PSI Audio’s A21M monitor (and the A17M too). In short, these speakers are

extraordinary and deliver a level of performance and accuracy that vanishingly few two-way designs can match,

and which would shame a great many three-way offerings. There is no denying that they are expensive, but the

cost is comparable to the few other monitors of similar performance and size. Auditioning is highly

recommended for serious high-end monitoring applications.

Alternatives

Compact two-way active monitors capable of delivering a similar or better level of performance to these PSI Audio monitors are scarce, but potential short-list alternatives should include the truly astonishing PMC AML2 (priced at $10,499 per pair), the superb ATC SCM20A SL Pro ($6700), and Geithain RL904 ($6200).

At a slightly more affordable level, the PMC TB2SA MkII ($3699) and similarly sized but three-way, sealed-cabinet Neumann (formerly K+H) O300 monitors ($7016) should also be considered solid contenders.

Class-G Amplification

Most readers will be broadly familiar with the concept of amplifier classes such as Class A, B, AB and D. Put very simply, a Class-A amplifier employs an output device (a valve or transistor) which conducts linearly on both the positive and negative halves of the audio signal. This approach has very low distortion, but is pretty inefficient and results in a lot of energy being wasted as heat. The Class-B topology improves the efficiency significantly, by using separate output devices to handle the positive and negative halves of the audio signal, but with the drawback that the transition from one side to the other results in ‘crossover distortion’. Class AB is a blend of these two ideas, biasing the output devices in such a way as to combine much of the Class-B efficiency while retaining the Class-A linearity, and this has been the dominant high-quality amplifier topology for decades.

In recent years, however, Class-D amplifiers have become more popular, mainly because they offer very substantial efficiency gains compared to Class-AB designs. Instead of employing output devices to vary the output current linearly, Class-D amplifiers work by switching the output devices either fully on or off at an ultrasonic frequency, the on and off durations (or ‘pulse width’) being modulated by the audio signal. An output filter averages the resulting current pulses to reconstruct the audio signal and remove the ultrasonic switching artifacts. The idea is closely related to the sampling process in a digital converter, although there is

biasing and switching.

0

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no quantising stage involved, and it remains a completely analogue system.

PSI’s approach in its range of active monitor speakers uses a less familiar amplifier topology called Class G. This maintains the inherent linearity of the Class-AB approach while improving significantly on its efficiency. At its heart, the design employs a low-power Class-AB amplifier, operating on relatively low power-rail voltages, which does most of the work. However, the output-stage circuitry is supplemented with additional output devices connected to much higher-voltage power rails. Most of the time, only the low-power amplifier operates, and the additional output devices are turned off — thus improving efficiency. But when the required output signal amplitude exceeds the voltage range of the low-power stage, these additional high-voltage output devices are switched on to facilitate the required higher-voltage signal peaks.

Controlling the switching of the high-voltage output devices is critical to avoid another form of ‘crossover distortion’, but when optimised this approach works extremely well, running virtually as cool as a Class-D design, but with the established audio quality and freedom from electromagnetic interference radiation artifacts of a traditional Class-AB amp. The output-stage biasing and switching is usually achieved with a number of diodes — far more than you would expect to find in a normal Class-AB amplifier — and these can be seen in the output stages of the amplifier chassis in the PSI monitors (see photo overleaf).

Published in SOS July 2011

A225-MTrue Music has BASS.

Deep Bass.




[email protected]

An exceptional piece of acoustic design, the A225-M sub-woofer/bass extension is equally suited to use as a mono sub-woofer in a surround sound application or as a bass extension in a stereo system. Designed to work in harmony with the A225-M Sub, all PSI Audio ‘A’ series speakers feature a frequency response roll-off function that, when combined with the A225-M Sub, extends the frequency range down to an incredible 24 Hz, whilst maintaining a flat response. The powerful class G outputs feature PSI Audio‘s unique “AOI” output stages, giving the A225-M an unprecedented impulse behavior. Each driver and amplifier unit is secured by a protection circuit, which is monitored by a red LED on the front panel. The electronics are housed in a unit mechanically isolated from the speaker cabinet to avoid resonance at high sound pressure levels. To provide stability and avoid cabinet resonance A225-M is built with a double-box design, combining two cabinets into a single beautifully finished unit.

Description


20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

0

-10

-20

-30

Monitor with -10dB Roll OffSPL@1m A225-M Acoustic SUM

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90


[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90


A 225-M

200 W

300 W

111 dB (single)

116dB / half space

24 - 100 Hz

±2 dB (28Hz - 65Hz)

90Hz

2x Ø 258 mm / Ø 210 mm

320 x 700 x 500

38.4 Kg


Phase and amplitude response compatible with all PSI Audio monitors.

Built in anti-resonance system in a double box cabinet.




Real balanced input with outputs for satellite systems.

Class G low temperature amplifier stage.

Amplifier unit acoustically uncoupled from speaker cabinet.

Orininal Technologies* : CPR, AOI, PSC.

Features

Further information: www.psiaudio.com

Technical DataPower RMS

Program power


Program Max SPL, 1m

Response at -6dB

Tolerances

Crossover frequency

Woofer's dim.

Ext. / Diaphragm

Dimensions


Net Weight

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

+10

0

-10

-20

-30

[dB]

25 31 40 50 63 80 100

125

160

200

250

315

400

500

630

800 1k

1k25 1k

6 2k 2k5

3k15 4k 5k 6k3 8k 10k

12k5 16

k

130

120

110

100

90

20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

+540

+360

+180

0

-180

[Deg]

+450

+270

+90

-90

Monitor with -10dB Roll OffSPL@-10dBu/1m A225-M


20 50 100 200 500 1k 2k 5k 10k 20k [Hz]

[dB]

-20

-30

-40

-50

-60

THD@-10dBu/1m A225-M

Monitor with -10dB Roll Off


Acoustic SUM

STEREO SYSTEM 5.1 SYSTEML

Sub in

R

IN 1

IN 2

LIN

K 1

LIN

K 2

-10dB ROLL OFF

LEVELCAL

A225-M

IN 1

IN 2

LIN

K 1

LIN

K 2 LEVEL

CAL

A225-M-10dB ROLL OFF

Otherchannelsdirect to

monitors.Roll offat cal

1=Gnd2=Hot3=Cold

115/220V Hi. ± 57V Low ± 18V

MAINS EMI LP ON/OFF FUSE TRAFO RECT. REG.

LIMITERLEVEL HP LP

TEMP. SENS

STANDBY

INPUT 1

LIMIT

POWER

CLASS GPOWER

AOI*PSC*

INPUT 2*A O I : Adaptive Output Impedance system.*PSC : Phantom Standby Control (on M series).

Puissance RMS

Power RMS200 W

Puissance programme

Program power300 W












Program Max SPL, 1m116dB / half space

Réponse à -6 dB


Tolérances

Tolerances±2 dB (28Hz - 65Hz)

Distorsions THD

Distortion THD< 1.5% (50Hz-200Hz)

Système

System1 Way(s)


Crossover frequency90Hz


Woofer's dim. Ext. / Diaphragm2 x Ø 258 / Ø 210 mm

Connecteurs

Connectors2 x XLR F / 2 x XLR M

Signal entrée



Box MaterialMDF / double box



43.1 / 38.4 Kg

Tension de secteur


Consommation


Humidité Moy / Max




Poids brut / net

Gross / Net Weight




[email protected]

160160

350

350

Min

imum

well-

aired s

pace

Fro

nt

350

260

700

50070

Front

Panel screwing

area

80

60

60 60

320

All dimensions are in mmAll dimensions are in mm


Front view

Acoustical axis

Mounting



±2±20%




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psi audio brochure

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