JBL 4315A/4315WXA 4315A: 350,000yen(one-set, around the 1978 time) 4315WXA: 360,000yen (one-set, around the 1978 time)

A compact-also in studio monitor-shaped 4 ways speaker system.

2108 of a 20cm cone type Woofer is adopted as low-pass 2203A of a 30cm cone type Woofer, and inside low-pass, and the horn type tweeter 2405 is adopted as a mid-high range 2105 of a 13cm cone type squawker, and for super-high regions.

It hangs by supporting metal fittings on the back, and a placement is also possible.

Finish of an enclosure has two kinds, 4315A becomes gray finish and 4315WXA serves as walnut finish. The black grill was attached to the saran network at 4315A. The blue grill was attached to 4315WXA. 

Scheme	4 ways, 4 loudspeaker bass-reflex scheme, and a bookshelf type
Unit	For low-pass: 30cm cone type (2203A) For inside low-pass: 20cm cone type (2108) For mid-high ranges: 13cm cone type (2105) For high regions: Horn type (2405)
Play frequency band	35Hz - 20kHz
Cross over frequency	400Hz, 2000Hz, 8000Hz
Directivity	80 degrees x 60 degrees (16kHz)
Impedance	8ohms
Output sound pressure level	89dB (new Japanese Industrial Standard)
Allowable input (RMS)	60W
Enclosure dimension	Woofer: 91L Mid Woofer: 2.8L
Dimensions	Width 521x height 854x depth of 327mm
Weight	43kg

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JBL 4313BWX 160,000yen(one set)

They are a diameter Woofer of 25cm, a diameter squawker of 13cm, and the compact 3 way system constituted from a diameter dome shape tweeter of 2.5cm. The optimal monitor loudspeaker for carrying out in the control room of a recording studio or a broadcast station, and an editorial office.

The result of the technology of JBL which have improved the image lateralization, such as an in-line placement of an extensive directivity unit and adoption of the good newly developed network of a phase response, has realized the transparent sound which was excellent in the property. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit	For low-pass: 25cm cone type For mid ranges: 13cm cone type For high regions: 2.5cm dome shape
Play frequency band	40Hz - 18kHz (±3dB)
Cross over frequency	1000Hz, 4000Hz
Directivity	130 degrees (15kHz)
Impedance	8ohms
Output sound pressure level	89dB/W/m
Allowable input	40W
Enclosure dimension	34L
Dimensions	Width 362x height 597x depth of 252mm
Weight	21kg

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JBL 4313WX 142,000yen(one-set, around the 1979 time)

Diameter Woofer LEof 25cm 111A, the control monitor system which adopted the in-line placement which attached three units of the diameter tweeter 066 of diameter squawker LEof 13cm5-9 or 2.5cm in a straight line on the vertical axis. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Using unit	For low-pass: 25cm cone type (LE111A) For mid ranges: 13cm cone type (LE5-9) For high regions: 2.5cm dome shape (033)
Frequency characteristic	40Hz-18kHz±3dB
Allowable input	40W(RMS)
Impedance	8ohms
Cross over frequency	1000Hz, 4000Hz
Output sound pressure level	89dB (new Japanese Industrial Standard)
Enclosure internal volume	34L
Dimensions	Width 362x height 578x depth of 252mm
Weight	19.3kg

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JBL 4312M 64,000yen(It is 1 set in two sets, around the 2000 time) Three-set 1-set package 4312M3:96,000yen(It is three sets and is 1 set.)

The style and appearance of 4312 serieses are the 3 way speaker systems which downsized to desktop as it is.

The 13.3cm white cone Woofer is carried in low-pass.
The accordion-pleats edge which raises a paper cone diaphragm and the swing linearity of a cone is adopted, and also the aluminum die-casting frame is adopted as a frame.

The 5cm cone type unit is adopted as a mid range. Moreover, the 1.9cm replace pure titanium dome tweeter is adopted as the high region.

The Attenuator which can adjust independently each sound pressure level of a mid range and a high region is carried.
Respectively, a coordination is possible for three steps.

It is little magnetic-shield design of influence in TV footage.
Moreover, the installment to the surface of a wall or a ceiling is possible by using optional mounting Plunkett etc.

Moreover, there was also 4312M3 package which made 4312M a three-set set (three-set 1 set 96,000yen). 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type - Magnetic-shield design
Unit etc.	For low-pass: 13.3cm cone type For mid ranges: 5cm cone type For high regions: 1.9cm dome shape
Frequency characteristic	60Hz - 40kHz
Output sound pressure level	89dB/2.83V/m
Impedance	4ohms
Allowable input	75W(RMS)
Cross over frequency	5000Hz, 10000Hz
Dimensions	Width 181x height 300x depth of 180mm
Weight	4.0kg
Option	Mounting bracket MTC-520 (an It is 1 set in two sets, 8,000yen) Adapter for ceilings MTC-601 (an It is 1 set in two sets, 3,600yen)

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JBL 4312SX 115,000yen(one-set, around the 2000 time)

The speaker system which expanded a power range of crown compass by leaps and bounds, and aimed at the correspondence to DVD-Audio, SACD, etc.

2213H which is a 30cm white cone type Woofer is adopted as low-pass.
The copper ribbon edgewise volume voice coil of the diameter of 75mm is used, and the SFG (symmetrical field geometry) magnetic circuit and the aluminum die-casting frame are adopted.
Moreover, the Aqua positive coating pulp cone is adopted as a diaphragm, and the accordion-pleats edge is used for an edge.

904Ti-1 of a 12.5cm pure titanium inverted dome mid range is adopted as a mid range.
In order to expand a waveguide-plunger motion area, while molding a diaphragm in the shape of a reverse dome shape, in order to suppress an occurrence of a splitting oscillation, the 37mm voice coil of a balance drive design is adopted.
The neodymium magnet is adopted as a magnetic circuit and the Tran Gent property and resolution are conjointly raised with the bucket structure by an aluminum die-casting frame, and the Ben Ted center pole piece which misses a back-pressure.

TW025Ti which is a 25mm replace pure titanium dome tweeter is carried in the high region.
a profit -- the lightweight aluminum voice coil which gave the Kopper coating to the pure titanium diaphragm of press molding is adopted.
Furthermore, "fellow fluid dumping" which heightens the vibration suppression effect is adopted at the same time it misses the heat of a diaphragm.

The succession variable Attenuator volume of a mid range / high region independency is equipped so that it can respond to usage various as a bookshelf type.

The enclosure has adopted the twin port type of a bass-reflex structure.
Moreover, while raising a baffle intensity by using 25mm thickness MDF material for a front baffle, the phase and diffraction of an inter-unit are controlled by forming a mid-high-range unit into flush mounting.
The sheath serves as walnut finish. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit etc.	For low-pass: 30cm cone type (2213H) For mid ranges: 12.5cm reverse dome shape (904Ti-1) For high regions: 2.5cm dome shape (TW025Ti)
Frequency characteristic	40Hz-50000Hz±0dB
Output sound pressure level	93dB(2.83V/1m)
Impedance	6ohms
Allowable input	150W(RMS)
Cross over frequency	900Hz, 3800Hz
Dimensions	Width 362x height 597x depth of 299mm
Weight	20.0kg
Option	Loudspeaker table lamp JS-50 (one set, 25,000yen)

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JBL 4312BMKII 78,000yen(one-set , around the 1999 time)

The black type 3 way speaker system of 4312.
The unit has composition only 4312MKII and whose unit of a high region are different.

2213H of the 30cm white cone type unit which adopted the copper ribbon edgewise volume voice coil of the diameter of 75mm is adopted as low-pass.
The SFG (symmetrical field geometry) magnetic circuit which realized the low distortion, and the aluminum die-casting frame excellent in the mechanical intensity are adopted.

12.5cm mid range driver 104H-3 which belongs to the unit of LE5 system is carried in the mid range.

035Ti of the 25mm pure titanium dome tweeter which molded the pure titanium material of the high hardness into the dome shape of 25micro thickness is carried in the high region.
A diamond edge pattern original with JBL and a reinforcement rib excellent in the linearity are adopted.

The enclosure serves as a characteristic layout which is the black finish which performed emboss processing of the skid, and aimed at the convergence of the voice source.
Moreover, the Attenuator which became independent in the mid range and the high region is carried. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit etc.	For low-pass: 30cm cone type (2213H) For mid ranges: 12.5cm cone type (104H-3) For high regions: 2.5cm dome shape (035Ti)
Frequency characteristic	45Hz - 20kHz (-6dB)
Output sound pressure level	93dB/2.83V/m
Impedance	6ohms
Allowable input	100W(RMS)
Cross over frequency	1100Hz, 4200Hz
Dimensions	Width 362x height 597x depth of 298mm
Weight	20kg

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JBL 4312MKII(WX/GY) 4312MKIIGY: 115,000yen(one-set, around the 2000 time) 4312MKIIWX: 105,000yen(one-set, around the 2000 time)

The 3 way speaker system which hits the advanced type of 4312.

30cm white cone Woofer 2213H which adopted the copper ribbon edgewise volume voice coil of the diameter of 75mm is carried in low-pass.
The SFG (symmetrical field geometry) magnetic circuit which drives a cone to low distortion by a symmetrical magnetic field, and the aluminum die-casting frame are adopted.

Cone mid range driver 104H-3 of the diameter of 12.5cm is carried in the mid range.

2.5cm replace pure titanium dome tweeter 052Ti which really molded the diamond structure edge original with JBL by precise processing technology is carried in the high region.

4312MKIIWX serves as a blue baffle and beautiful walnut Veneer-Sheet finish of grain, and the enclosure serves as 4312MKIIGY gray paint finish.

The Attenuator which can adjust independently the output sound pressure level of a mid range and a high region is carried. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit etc.	For low-pass: 30cm cone type (2213H) For mid ranges: 12.5cm cone type (104H-3) For high regions: 2.5cm dome shape (052Ti)
Frequency characteristic	45Hz - 22kHz (-6dB)
Output sound pressure level	93dB/2.83V/m
Impedance	6ohms
Allowable input	100W(RMS)
Cross over frequency	2000Hz, 5000Hz
Dimensions	Width 362x height 597x depth of 298mm
Weight	20kg

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JBL 4312XP 126,000yen(one-set, around the 1990 time)

The speaker system which adopted the material original with an old enclosure and realized clearer and high-definition sound in order to refine the tone quality of 4312 serieses further.

2213H which is a 30cm cone type unit is adopted as low-pass.
The SFG magnetic circuit original with low distortion JBL is adopted as a magnetic circuit. The cone paper coated [ the special reinforcing material ] is adopted as a diaphragm. And the clear bass whose dumping was effective is gained.
Moreover, rigidity is raised by adopting aluminum die-casting as a frame.

104H-3 which is a 13cm cone type unit is carried in the mid range.

035Ti which is a pure titanium tweeter is carried in the high region.
Pure titanium was molded into the precision dome of 25micro thickness, and the skillful tone quality is realized in combination with the diamond edge suspension aiming at the improvement in a high region property, and the rib pattern which prevents a splitting oscillation.

The Attenuator which can control each of a mid range and a high region is carried.

The enclosure laminated the high-density material "reaction mall dead form" original with JBL which has the vibration suppression effect excellent in front particle board first, and has dumped the unnecessary oscillation of the whole enclosure.
Furthermore, in order to decrease a primary reflection of the play sound on the top layer of a baffle which had had a delicate ill effect on the stereo image, the "neo plane form" is adopted as the perimeter of a unit, and the tone-quality failure by the primary reflective sound in a mid-high range is especially made into the minimum.
Moreover, there were two kinds of finish, walnut finish and black finish. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit etc.	For low-pass: 30cm cone type (2213H) For mid ranges: 13cm cone type (104H-3) For high regions: Dome shape (035Ti)
Frequency characteristic	45Hz - 20kHz
Output sound pressure level	93dB/W/m
Impedance	8ohms
Allowable input (succession)	100W
Cross over frequency	1100Hz, 4200Hz
Dimensions	Width 362x height 597x depth of 298.5mm
Weight	20kg

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JBL 4312A/4312ABK 4312A: 128,000yen(one set, the 1986 release) 4312ABK: 115,000yen(one set, the 1986 release)

The speaker system which raised completeness as a succeeding machine of 4312 by introducing the technology which takes an aim in digital age.

2213H which is a 30cm cone type Woofer is carried in low-pass.
The SFG magnetic circuit which is proud of a low distortion is adopted as a magnetic circuit, and in order to gain the bass whose dumping was effective against cone paper, the coating strengthening agent original with JBL is applied.
Moreover, the product made from aluminum die-casting is adopted as a frame, and the oscillation of the magnetic-circuit part is suppressed.

104H-3 of a 13cm cone type unit is carried in the mid range.
This unit is what added the enhancement to what has been used by the JBL monitor, made the voice coil new, coated also on cone paper, and has obtained the smooth frequency response and the large directivity.

035Ti which is a dome shape tweeter is carried in the high region.
It was light, rigidity was high, the pure titanium material excellent also in the endurance was molded into the dome of 25-micron thickness, the diamond edge pattern and reinforcement rib which obtained the Tips in the origami work of Japan were combined, and the outstanding response has been obtained.

The enclosure has a bass-reflex structure.
Finish had two kinds of 4312ABK of 4312A of walnut finish, and black finish. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit etc.	For low-pass: 30cm cone type (2213H) For mid ranges: 13cm cone type (104H-3) For high regions: Dome shape (035Ti)
Frequency characteristic	45Hz - 20kHz
Output sound pressure level	93dB/W/m
Impedance	8ohms
Allowable input	100W
Cross over frequency	1.1kHz, 4.2kHz
Enclosure dimension	40L
Dimensions	Width 362x height 597x depth of 298mm
Weight	20kg

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JBL 4312 143,000yen(one set, 1982) 153,000yen(one set, 1983)

4312 is a succeeding machine of 4311B which obtains an overwhelming validation and is playing an active part in the studio in the world, and the broadcast station widely also as a home youth. A tone quality and a property are Hideyasu to the last in 3 way system of the all cone constituted from a 30cm aperture Woofer, a 13cm aperture squawker, and a 3.6cm aperture direct radiator.

Moreover, the design which can perform level adjustment of effective sound where a grill is attached is also the special feature of this loudspeaker. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit	For low-pass: 30cm cone type For mid ranges: 13cm cone type For high regions: 2.5cm dome shape
Play frequency band	45Hz - 18kHz (±3dB)
Cross over frequency	1000Hz, 4000Hz
Impedance	8ohms
Output sound pressure level	90dB/W/m
Allowable input	150W (succession special NetWare program)
Enclosure dimension	42L
Dimensions	Width 362x height 597x depth of 327mm
Weight	24kg

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JBL 4311B/4311BWX 4311B: 135,000yen(one set) 4311BWX: 140,000yen(one set)

3 way speaker system developed as an object for the monitor in the control room which has a restraint in a space. Little clear distorted sound is reproduced in high efficiency.
Placement peculiar to this model of arranging a Woofer at the topmost part and putting an Attenuator on a lower is because it is designing supposing a hanging placement.

The thing of the diameter of 30cm is adopted as a Woofer, and adoption and a diameter [ of 3.6cm ] direct radiator are used for a squawker for the diameter of 13cm. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Unit	For low-pass: Diameter Woofer of 30cm For mid ranges: Diameter squawker of 13cm For high regions: Diameter tweeter of 3.6cm
Play frequency band	45Hz - 15kHz (±3dB)
Cross over frequency	1500Hz, 6000Hz
Impedance	8ohms
Output sound pressure level	91dB/W/m
Allowable input	40W (succession special NetWare program)
Enclosure dimension	40L
Dimensions	Width 362x height 597x depth of 298mm
Weight	20kg

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JBL 4311A/4311WXA 4311A: 120,000yen(one-set ,around the 1979 time) 4311WXA: 125,000yen(one-set, around the 1979 time)

The control monitor of three ways developed as a monitor of a recording studio, an editorial office, a control room, etc. with the restraint on a space, and an outdoor sound recording.

"Diameter Woofer 2213 of 30cm" "Diameter squawker LEof 13cm5-2" Supposing the hanging setting, a Woofer is attached to a upper portion and, as for three units of "direct radiator LE25 of the diameter of 3.6cm", the Attenuator is attached to the lower.

There were two kinds of finish of an enclosure and there were 4311A of gray finish and 4311WXA of walnut finish. A saran network is common to black. 

Scheme	3 ways, 3 loudspeaker bass-reflex scheme, and a bookshelf type
Using unit	For low-pass: 30cm cone type (2213) For mid ranges: 13cm cone type (LE5-2) For high regions: 3.6cm (LE25)
Frequency characteristic	45Hz-15kHz±3dB
Allowable input	40W(RMS)
Impedance	8ohms
Cross over frequency	1500Hz, 6000Hz
Output sound pressure level	91dB (new Japanese Industrial Standard)
Enclosure internal volume	42.5L
Dimensions	Width 362x height 597x depth of 298mm
Weight	19kg

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JBL 4305H 49,000yen(one-set, around the 2003 time)

The 2 way speaker system which employed honed Leiber.

Color free and the unbleached 20cm (8 inches) white cone Woofer which harnessed a feeling of a material of natural pulp are carried in low-pass.
While adopting a high rigidity aluminum die-casting frame, the low-pass play is improved by preparing a bass-reflex single word I/O port symmetrical with an enclosure.

The horn type tweeter is carried in the high region.
The flat front type horn which lengthened width to enclosure both the re-degree is combined with the 2.5cm (1 inch) compression driver by a pure titanium diaphragm.

The succession variable level Attenuator which can adjust honed Leiber's Output voltage is carried.

The MDF material of 19mm thickness was used for the enclosure, and black ash grain tone finish is adopted.

The gilding binding post type loudspeaker terminal also corresponding to an interconnection of a very-thick loudspeaker cable is adopted. 

Scheme	2 ways, 2 loudspeaker bass-reflex scheme, and a bookshelf type
Using unit	For low-pass: 20cm cone type For high regions: Horn type
Frequency characteristic	50Hz - 35kHz
Allowable input	75W(music)
Impedance	6ohms
Cross over frequency	4.5kHz
Output sound pressure level	89dB/2.83V/m
Dimensions	Width 273x height 460x depth of 284mm
Weight	11.5kg

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JBL 4302 55,000yen( one-set, around the 2001 time)

2 way speaker system which inherited the concept of 4301 which began the voice checking within an outside broadcast vehicle, and played an active part broadly as a compact studio monitor, and was developed.

The 20cm cone type Woofer which adopted color free and the unbleached white cone which harnessed a feeling of a material of natural pulp is carried in low-pass.

The high-temperature hardening treatment by nitrogen gas is performed to a pure titanium diaphragm, and the 2.5cm ten packet-assembler/disassembler titanium dome shape tweeter which raised the hardness of the diaphragm is carried in the high region.
Furthermore, upper register play capacity and directional characteristics are improved by combining a short horn type Phi 鋭 spray.

The magnetic-shield design is performed and audio-video theater room can also be used.

According to a room environment or the play source, the succession variable level Attenuator which can adjust the output sound pressure level of upper register is carried.

MDF is used for an enclosure and native wood thrust board finish of the high gross clear coat is given to the blue baffle of JBL studio monitor tradition. 

Scheme	2 ways, 2 loudspeaker bass-reflex scheme, and a bookshelf type
Using unit	For low-pass: 20cm cone type For high regions: 2.5cm dome shape
Frequency characteristic	40Hz - 40kHz
Maximum permissible input	75W
Impedance	6ohms
Output sound pressure level	89dB/2.83V/m
Cross over frequency	5kHz
Dimensions	Width 274x height 435x depth of 290mm
Weight	10.6kg

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JBL 4301BWX 75,000yen(one-set, around the 1982 time) 93,000yen(one-set, around the 1983 time)

The compact monitor loudspeaker developed as an object for an edit of a broadcast station or a studio.

116H which is a 20cm cone type Woofer is adopted as low-pass.
It is suitably developed severely in pursuit of input characteristics-proof etc. for the monitor, and the Low-noise-izing is attained.
Moreover, the hard cone paper with a corrugation, the diameter voice coil of 5cm of a precision design, pole piece and gap which have improved the high region property, the frame made from aluminum die-casting, etc. were adopted, and the more smooth frequency characteristic is acquired.

LE26 of a 3.6cm direct radiator is adopted as a high region.
Adoption of hard cone paper and a center dome has realized the directional characteristics of level and 90 degrees (10kHz) of perpendicularities.
Moreover, the perimeter of a unit is wrapped in a resin system material with a taper, and while improving a consistency with a baffle board, the improvement in directional characteristics or energetics is aimed at.

The network part has adopted the thing in consideration of a phase response or an impedance correction.

19mm thickness high-density compressed is used for an enclosure. 

Scheme	2 ways, 2 loudspeaker bass-reflex scheme, and a bookshelf type
Unit	For low-pass: 20cm cone type (116H) For high regions: 3.6cm direct radiator (LE26)
Play frequency band	45Hz-15kHz±3dB
Directional characteristics	90 degrees (horizontal and vertical)
Cross over frequency	2500Hz
Impedance	8ohms
Output sound pressure level	88dB/W/m
Allowable input	15W(RMS)
Enclosure dimension	28L
Dimensions	Width 291x height 483x depth of 306mm
Weight	12.7kg

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JBL 4301WX 125,000yen(one-set, around the 1979 time)

　
The broadcast monitor system of two ways developed for the purpose of the using in the limited spaces, such as a broadcast station, an editorial office, a control room.

It consists of a 20cm Woofer and a 3.6cm direct radiator. 

Scheme	2 ways, 2 loudspeaker bass-reflex scheme, and a bookshelf type
Using unit	For low-pass: 20cm cone type (116A) For high regions: 3.6cm (LE25-2)
Frequency characteristic	45Hz-15kHz±3dB
Allowable input	40W(RMS)
Impedance	8ohms
Cross over frequency	2500Hz
Output sound pressure level	88dB (new Japanese Industrial Standard)
Enclosure internal volume	28L
Size	Width 291x height 483x depth of 306mm
Weight	12kg

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JBL SE408S 164,000yen(around the 1970 time)

Silicon transistor power amplifier with the output of 40Wx2.
An internal specification is almost the same as SE400S.
In order to use it, inserting in a speaker cabinet, a shelf, etc., it mainly has a structure without a cover.

The surface panel serves as a design as which the radiator of the transistor also served.

The scheme called Energizer is adopted.
A printed-wiring board is in the interior by this scheme, and it is this substrate,several kinds of circuitries are prepared according to the speaker system of JBL, and it has also become an equalizer with which a dumping factor a model number -- also controls the frequency characteristic including power amplifier and a loudspeaker in an ideal property by reputting.

The slot which inserts SE408 in an enclosure backplane is established in some loudspeakers of JBL. 

Form	Stereo power amplifier
Effective output	40W+40W (8ohms)
Frequency band	3Hz - 20000Hz
Input sensitivity	0.8-3V
S/N ratio	90dB
THD	0.15%(40W)
Dumping factor	27 (8ohms)
The semiconductor used	Transistor: 22 pieces Diode: 20 pieces
Dimensions	Width 378x height 110x depth of 160mm

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JBL SE400S 178,000yen(around the 1970 time)

Silicon transistor power amplifier with the output of 40Wx2.
An internal specification is almost the same as SE408S.
In SE408S, the fraction which was a front-view panel is a rear panel, and it has a structure which the cover attached to the overall, and has a structure in which an equalizer board appears from the acrylics part of the center of a whole surface panel.
The rear panel serves as a design as which the radiator of the transistor also served.

The scheme called Energizer is adopted.
A printed-wiring board is in the interior by this scheme, and it is this substrate,several kinds of circuitries are prepared according to the speaker system of JBL, and it has also become an equalizer with which a dumping factor a model number -- also controls the frequency characteristic including power amplifier and a loudspeaker in an ideal property by reputting.

It is in order to insert in SE408 for having been in the enclosure backplane of some loudspeakers of JBL. 

Form	Stereo power amplifier
Effective output	40W+40W (8ohms)
Frequency band	3Hz - 20000Hz
Input sensitivity	0.8-3V
S/N ratio	90dB
THD	0.15%(40W)
Dumping factor	27 (8ohms)
The semiconductor used	Transistor: 22 pieces Diode: 20 pieces
Dimensions	Width 378x height 110x depth of 160mm

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JBL SG520 268,000yen(around the 1970 time)

Control amplifier which did not use any rotated type thumb but consisted of only straight line type controls and push-button switchpoints.

Although the model number has not changed from the early model to the second-half model, the enhancement is added to the internal circuitry.

If a 1kHz testing tone oscillator is built in and the relay control F22 is combined with this, it is possible to perform the stereo sound-volume balance control called Aural Null Balancing System.

Although a front is an aluminum panel, there is SE520E which can change supply voltage by SG520G of the gold panel set by finish of power amplifier SE400S, and an expert model. 

Form	Stereo control amplifier
Output	3V
Frequency band	20Hz - 20000Hz
Input sensitivity	Phono:6mV AUX:300mV
THD	0.15
Tone control	High region: 20kHz and +21 -17 dB Low-pass: 20Hz, ±17dB
An attached circuitry	Loudness control With an NULL BALANCE

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JBL SA660 291,300yen(around the 1970 time)

An Integrated Amplifier with the output of 60Wx2.

As a modification from SA600, the tone control serves as a right-and-left independency.

The stream composition has a structure which left the basal line, respectively and made SG520 and SE400S simple. Moreover, the equalizer circuitry carried by SE400S is not carried.

The loudness control and the NULL BALANCE are carried

Form	Stereo Integrated Amplifier
Effective output	60W+60W (8ohms)
Frequency band	20Hz - 20000Hz
Input sensitivity	Phono: 4mV, 8mV, 16mV (switching type) AUX:250mV
S/N ratio	72dB
THD	0.2%
Tone control	High region: 20kHz, ±16dB Low-pass: 20Hz, ±18dB
Dumping factor	32 (8ohms)
The semiconductor used	37Tr, 23Di
Dimension	Width 412x height 128x depth of 350mm
Weight	11.8kg

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