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Among the Setup features are input-level trim, so that the volume doesn't "jump" between inputs; a Pass Thru mode for use in a multichannel sound or home theater system; adjustments for the fluorescent display and meter brightness; input title reassignment (for instance, if you have a DVD player plugged into the Aux input, you can change that input's label to read "DVD"). And, of course, in Setup mode you can change MM capacitance and MC resistive loading. You can even set the C1000 for mono operation, via the Setup menu or the remote control. Actually, there are two remote controls: a…
Sidebar 1: Specifications
C1000T: tube preamplifier. Tube complement: eight 12AX7. Frequency response: 10Hz–20kHz, +0/–0.5dB. THD: 0.08%, 20Hz–20kHz (no level quoted). Signal/noise ratios: high level: 93dB (ref. 2.5V output unbalanced, 5V balanced); phono, 80dB(ref. 10mV input, MM; 1mV input, MC). Maximum output: 8V RMS single-ended, 16V RMS balanced. Output impedance: 220 ohms. Maximum input levels: 5V single-ended, 10V balanced, high level; 50mV (MM), 5mV (MC), phono. Sensitivity, high level, for 2.5V output: 450mV (high level), 4.5mV (MM), 0.45mV (MC).
Serial Number Of Unit…
Sidebar 2: Associated Equipment
Analog Sources: Continuum Audio Labs Caliburn turntable; Continuum Cobra, Graham Phantom tonearms; Lyra Titan (stereo & mono), Miyabi/47 Labs cartridges.
Digital Sources: Musical Fidelity kW SACD player, Alesis Masterlink BPT-modified hard-disk recorder.
Preamplification: Manley Steelhead, Blue Amp 42, PS Audio GCPH, Oracle Temple phono preamplifiers.
Power Amplifiers: Musical Fidelity kW, mbl 9007 monoblocks.
Loudspeakers: Wilson MAXX 2, Merlin VSM.
Cables: Phono: CrystalConnect Piccolo. Interconnect: Acrolink 6100, Shunyata Research…
Sidebar 3: Measurements
I performed full sets of measurements on both McIntosh preamplifiers, for both balanced and unbalanced operation, but the two units turned out to be electrically so similar that I've combined my comments on both into a single sidebar.
The phono stages, of course, are unbalanced only; I examined their behavior at each preamp's Processor Out jacks. The MM stages of the C1000P and C1000T are noninverting and offered a voltage gain of 40.1dB and an input impedance of 47k ohms across most of the audioband, the latter dropping inconsequentially to 42.5k ohms at…
I'll say one thing right off about the Infinity RS-1B: It sure looks as if you're getting your money's worth.
The system comes in five sections: two woofer columns, two upper-range columns, and an active crossover and servo control module. Each bass column contains six 8" polypropylene-cone woofers. Each upper-range column contains seven of Infinity's proprietary EMIM ribbon midrange drivers and four EMIT ribbon tweeters (one of them aiming out the rear, of all things!). System crossovers are at 125Hz (nominal), 750Hz, 3kHz, and 8kHz, and the number of operating drivers diminishes as the…
Sidebar: Testing for Oscillation
Here is the most straightforward way of ascertaining whether a power amplifier will be stable (ie, won't oscillate) in actual use, with adequate protection against damage if it does oscillate. Low-current fuses are the cheapest form of protection.
If the amplifier is already equipped with speaker fuses in its outputs, replace these with 0.25A (250mA) fast-blow fuses. (If it hasn't its own fuses, buy a couple of standard in-line fuse holders, put one in series with the Hot output from each amp channel, and install the 0.25A fuses.)
Connect…
Anthony H. Cordesman also wrote about the RS-1B in April 1985 (Vol.8 No.4):
It is a 14-mile drive from my mansion to the outer gates of the estate. I normally enjoy the quiet groveling of my peasants as the chauffeur drives my Rolls along this route. More and more, however, these peasants stop my Rolls to ask why I review so many expensive speakers. My answer—as I casually flick their broken and mangled bodies off the fender—is that expensive speakers sound better.
The Infinity Reference Standard 1B is a good case in point. Truly a speaker for members of our social and economic…
J. Gordon Holt returned to the RS-1B in November 1985 (Vol.8 No.7):
In my review of the RS-1B (Vol.8 No.4), I commented on that speaker's tendency to exaggerate grundge in the program material by adding what sounded like extremely narrow response spikes in the mid to upper treble. Since then, Infinity provided us with a modification kit for the passive crossover network feeding the mid-tweeter. The modification involves changing a potentiometer, and adding a resistor, capacitor, and choke to the crossover. It's more difficult than the instructions imply because the leads on the cap and…
Anthony H. Cordesman wrote again about the RS-1B in March 1986 (Vol.9 No.2):
No speaker ever totally disguises the compromises it must make with the laws of physics. Infinity's two largest monitor speakers, however come as close to hiding theirs as any full-range speaker available. The Infinity IRS has long ranked as one of the top two or three speakers in the world. The RS-1B has slowly emerged as one of the top two or three speakers for the ordinary home.
I now use the RS-1B as my home reference speaker, and a nearby IRS-III at Excalibur Audio as a listening "control" when I'm…
J. Gordon Holt returned to the RS-1B in April 1986 (Vol.9 No.3):
While I (currently) favor the MartinLogan Monoliths because of their incredible you-are-there realism, I still go back to the Infinity RS-1Bs from time to time for their awesome quality of power and excitement. The Infinities can give me goosebumps more often than any other speakers I've had on hand; every audiophile needs that kind of a fix from time to time.
After a while, though, the RS-1B's peculiar (apparent) sluggishness gets to me, and I start to long once more for the delicacy and transparency of the…