Linn Audio has a unique design philosophy regarding crossover design. We abide by the principle that the fewer components the better. All components, no matter how high quality, alter and color the sound, and at worst, add distortion and phase shifts to the signal. This is especially true of crossover components; capacitors and inductors. Most system designers of high-end speakers choose or design random driver components, that may not be good matches for each other, and compensate for these mismatched drivers by the use of massive and complex crossover designs, necessarily requiring many components in the signal path. We believe this philosophy is flawed!
We have started with the other end of the system, the drivers themselves, and have chosen not only the best we can find with regard to musicality and low distortion, but that match each other well, in terms of sensitivity, impedance and complementary frequency ranges. By taking this path to design of the system, we can minimize the components required to create a full audio spectrum, held to within +/– 3 db. It is very difficult to do, but we have done it, with the Reference Granite system. To take this design philosophy one step further, we have set up the system for bi-amping, or tri-amping and provided a switch to further reduce the components necessary for a full spectrum, yet flat frequency response. It has been said that: “the best sounding component is none at all!” So, we cannot have absolutely none, but we have provided the next best thing; minimal components in the signal path. And as stated, when the system is bi-amped, or tri-amped, an absolute minimum of components need be employed. This is one of the main reasons why the Reference Granite has a very pure and clean sound, one that cannot be matched by systems that use complex crossover designs.
All the internal components are of the highest quality available, with the use of polypropylene film and foil capacitors, air core foil-type inductors and WBT type insulated gold binding posts. The internal wiring is also selected from the best grades and sizes of copper wire, while all connections are point to point, and soldered with WBT silver solder. Resistors used for balancing the separate driver components (when mono-amped) are Mundorf brand and are of a high wattage, and flame-proof type, that will handle plenty of power.
Unique 3-way Connectivity
A new feature of the Reference Granite is the addition of an extra binding post plate, with 2 additional pairs of binding posts, and a second crossover switch. The internal wiring is such that there are 3 different possibilities to connect the system to amplifiers, according to the taste and preferences of the user. The first two are as stated above, a single amp driving the entire system, or second and third amplifiers driving the mid-range and tweeters, using the internal crossover networks. But it is known that additional clarity and transparency may be had by the direct connection of the amplifiers to the drivers, with absolutely zero components between the output of the amplifier and its associated driver, except for the speaker cable.
Recent experimentation by Linn Audio has confirmed this hypothesis, and found that the clarity, definition, imaging and sense of “presence” are all enhanced by this direct method of connection. By this method, you eliminate the reactive components in the load level signal path (which can be compared to pushing and pulling on an object with a rubber band) and also eliminate the intermodulation distortion by preventing audio signals from the unused portion of the spectrum from entering the amp altogether. This is especially important with the bass signals; i.e. keeping them out of the mid and high range amps. Of course, a crossover must be employed, but it is used at the line level, that is, the input side of the amplifier, and the best way to accomplish this is with an active crossover unit.
Introducing the New Linn Audio Active Crossover/Preamp Module
Linn Audio now makes a completely unique active crossover unit, especially designed and configured for the Reference Granite speaker system. It is unique, as it combines the functions of a preamp as well as those of an active crossover. When using this crossover, you do not need a separate preamp, which not only saves you the cost of the preamp, but eliminates many more components in the signal path – a follow through of our design philosophy for minimizing components in the signal path to the greatest possible degree. Consequently, there is minimal coloration of the music. The best possible sound can then be achieved: clarity, detail, definition, low distortion, and overall “presence.” You simply cannot obtain a better performing preamp than ours, regardless of price, and you also get the benefit of the active crossover functions (as above) and all the advantages of multi-amping, with the amps directly coupled to the drivers.
The 3 Options for Connecting the System
1.) A single amplifier connected to all the drivers, using the internal crossover components.
2.) Tri-amp, with a fairly powerful, and preferably, solid state amp driving the low end, and a second amplifier, preferably an SET tube type amp (and one of very modest power may be employed) driving the mid-range, and a third amp, either tube or solid state, and of modest power, driving the high end, all using the internal crossover components, and utilizing the Linn Audio passive balancing network (see below.)
3.) Tri-amp, as above, but connecting the outputs directly to the low, mid, and high frequency drivers and bypassing the internal crossover components for these three drivers, using an active crossover unit for frequency control of the crossover points between the drivers.
The four binding posts, as well as the 2 toggle switches on the rear of the newly designed Reference Granite cabinet may be connected and configured for any one of the above 3 connection options, giving the user ultimate control of the resultant sound.
Of all these methods, the Linn Audio favorite is option number 3. This is what we use for all our testing and critical listening. But the user is free to experiment, and determine what is the most desirable for his or her own listening pleasure.
To tri-amp, using the internal crossover components, one needs a balancing network between the preamp and the separate power amps. Linn Audio now supplies this network free of charge, with the purchase of any system. It uses only stepped attenuators for the control of the three stereo amps, for the highest quality sound, and essentially zero coloration.
We also supply the instruments and test signals that can be used to obtain the proper balance between the amps, as well as full instructions on how to do so; also at no extra charge.