What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





Fostex RM 765


The typical placement of speakers in the typical room results in a confusion of sound. You end up hearing a lot of the room colorations and reflections mixed in with the direct source. Sure, you can spend even more money and equalize the room. Even then you may have to invest in an outboard crossover in order to compensate for the loudspeakers design.
Avoid all these problems with Fostex Near-Field Monitors. They are Point Source, coaxial speakers. A,, the sound emanates from a point reference, just like in nature, so all the sound reaches your ears at the same time. Stereo imaging is rock solid.
This design produces a "sweet spot" so you know that what you're hearing from the RM Series will sound proportionally the same in a car, on a hi-fi system or through a custom-tuned playback system in the studio.
An unusually low crossover point gives you another imoprtant benefit not found in conventional designs: vital midband information like vocals will not be modulated by high impact low frequency sounds like kick drums.
The same RP patented driver gives you uniformly flat high frequency response in all three models; the woofers increase from 6,5 inches to 8 inches to 10 inches. The two drivers in the RM 765 are the identical elements in the RM 865 3-way system, which simply adds a 10-inch woofwr.
This larger system is also ready for biamplification. In our listening tests with 800W -1000W per side, these beauties have generated 116 dB SPL at the console with no audible distortion. The Near-Field Monitors from Fostex give you clarity and punch and definition - as loud as you need it.



The Initail Reference
RP stands for Regulated Phase. It's new a new trasducer technology which has been under development at Fostex for the last ten years. So far, more than 20 international patents have been awarded. The first products with the RP Technology were Headphones. The idea worked so well, the inventors immediately began applying it to the reciprocal trasducer, the microphone.
A whole series of microphones now exists' with the same basic principles embodied in the new RM 765 and RM 780 tweeters. The essential idea of this RP Trasducer is a flat, thin film diaphragm onto which the voice coil is printed; this assembly is then suspended between magnetic circuits arranged on both side of the diaphragm, with the same polarities facing each other and the opposite polarities adjacent to one another.
The end result of this arrangement permits the diaphragm to be driven with absolute uniformity. Which means it doesn't sound differently at different levels. It provides the same uniform frequency response across an extremely wide dynamic range.
It won't break up, either. Which means three won't be the usual high frequency distortion to mask the over-use of 12 kHz boost, for example.
Because the printed film diaphragm moves identically in both directions, and the entire diaphragm surface is with in the magnetic field, it by-passes all of the response variations caused by conventional mounting designs. There simply is no mechanically induced distortion in the RP tweeter. It functions as an edgeless device.
In this sense, the double spider design of the RM-Series woofers is the perfect complement to the RP tweeter. In a conventional single spider design, the compliance from one direction differs from the other. This difference produces unacceptable distortion, particularly in the second harmonic region. Fostex engineers added a second spider in a push/pull complementary configuration to cancel the compliance effects of a single spider design. The result is a 10 dB improvement in second harmonic distortion. A 2" voice coil/magnet assembly and a computer modeled bass reflex design complete the profile of what is definitive low and response in the Reference Monitor Series.





Specifications
RM 765
Enclosure Type:  Vented reflex
Power Capacity: 
150 watts continuous program power;
75 watts continuous pink noise.
Frequency response (2 TT or 4 TT):  58 Hz to 20 kHz  ±3 dB
Sensitivity (1W, 1m):
2 TT : 93 dB
4 TT : 90 dB
Reference efficiency
2 TT : 1,25 %
4 TT : 0,63 %
Distortion (10 W):
less than 2%  2nd harmonic;
less than 1% 3rd harmonic (from 58 Hz to 20 kHz)
Nominal impedance:  8 ohms
Miniumu Impedance:  6,5 ohms
Controls:  Field controls; High frequency level
Cabinet finish:  Mar resistant matle
Dimensions (W x H x D):  264 x 430 x 270 mm (10 x 17 x 10 inches)
Weight net:  8,5 kg (18,7 lbs)

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