The appearance alone of the D-250 inspires respect. The amplifier is huge, with most of its 138-lb weight coming from massive power and output transformers. This is not, if you'll pardon the observation, a product to be taken lightly. Neither is it something that we recommend buying by mail-order, partly…
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The D-250 is the flagship of Audio Research's power amplifier range and, at 250 watts per channel, is the most powerful all-tube stereo amplifier currently available in the US. Under the circumstances, then, it is not surprising that it should also be one of the heaviest and largest.
All large-value capacitors in the signal path have polypropylene dielectric, and are bypassed with small-value polystyrene caps. There are only five such banks in the signal path: two per side plus an additional one for the phase inverter.
Phase inversion is accomplished in an unusual manner. Instead of drawing opposite-polarity signals from the plate and cathode of a single triode stage, Audio Research simply uses an extra triode stage (padded down to unity gain) to invert polarity for the "pull" side of the circuit. This eliminates much of the imbalance between the + and the - signals…
Before starting my serious listening tests for this report, I let the D-250s (yes, two of them) warm up on Standby for 24 hours, then at normal idle for another two. Listening was done through the Infinity RS-1Bs, as well as through a pair of late model Watkins WE-1s (for full-range auditioning). My Martin-Logans were back at the factory for repair and upgrading. Associated equipment included Audio Research's SP-11 preamp, a SOTA Sapphire turntable, an Ortofon MC-2000 phono cartidge with its matching stepup transformer, the Well-Tempered Arm, a modified Revox A77-II playing first- and second…
With less demanding loads, the low-end characteristic which sounds "right" (or "best," if you prefer) will be as dependent on the loudspeakers used as on the amplifier. As always, the name of the game here is mating complementary products—speakers and amps whose LF behaviour offsets one another's idiosyncrasies. I would hesitate to say that the D-250's bottom end is more or less accurate than that of other amps which seem to produce "better" bass with the speakers I have on hand, but in comparison with the average of powerful amps auditioned recently, the D-250's low end sounds rather lean—…
Sidebar 1: Specifications
Description: All-tube stereo amplifier. Power output: 240W below 1% THD from 20Hz to 20kHz into 16 ohms; clipping point 250W. Power bandwidth: -3dB at 12Hz and 60kHz. IM distortion: below 0.1% at 1dB below rated output. Sensitivity: 800mV for rated output. Input impedance: 75k ohms. Damping factor: approx 20. Hum and noise: 90dB below rated output. Power consumption: 450W in Standby mode, 900W at idle, 2kW at rated output.
Dimensions: 19" W by 10½" H by 203/4" D. Weight: 138 lbs.
Price: $6500.
Manufacturer: Audio Research Corporation, 3900 Annapolis…
BILLY BRAGG & WILCO: Mermaid Avenue
Elektra 62204-2 (CD). 1998. Billy Bragg, Wilco, Grant Showbiz, prods.; Jerry Boys, eng.; Nora Guthrie, exec. prod. AAD? TT: 49:42
Performance ****?
Sonics ****
Elektra 62204-2 (CD). 1998. Billy Bragg, Wilco, Grant Showbiz, prods.; Jerry Boys, eng.; Nora Guthrie, exec. prod. AAD? TT: 49:42
Performance ****?
Sonics ****
You gotta give Billy Bragg and Wilco credit. Not only did they interrupt their respective careers for this admittedly intriguing side project, they also dissected and shoved their hands deep into the guts of one of this country's more contradictory musical personalities: Woody Guthrie. The idea was to hit a horribly difficult trifecta: pay homage to Guthrie's spirit, create their…
I first met Tony Federici at a 1986 high-end show in Lucerne, Switzerland. He was at that time distributing Perreaux amplifiers in the US; the dem room Perreaux shared with KEF and McIntosh overlooked Lake Lucerne and Wagner's villa at Tribschen, perhaps the most idyllic setting for Show sound I have ever experienced. Tony was educated as a philosopher: In the 10 years I've known him, I have never known him at a loss for an opinion. It's all the more strange, therefore, that Stereophile has never asked him to submit to the ordeal of a formal interview.
I put this oversight right at HI-FI…
Federici: Right. And that allowed the speaker manufacturers to then create less expensive loudspeakers with a lot more freedom. About seven or eight years ago, it was only the very expensive loudspeakers that had the freedom of offering widely varying impedances because you needed very expensive amplifiers to drive them. We fed on the market and the market fed on us. And changed it radically, I think.
Atkinson: What was the stimulus for your Acurus line?
Federici: We brought out Acurus because, according to the dealers, there was a need for a lower-priced, US-made, properly made—…
So what's happened is that people no longer know what the live event sounds like. That's a serious problem, whether it's Home Theater or audio. That's in the US. In other countries, I still think that there is more knowledge of what the actual instruments sound like. But this country thinks if they go to a Broadway show and they hear all that noise and distortion coming out of loudspeakers that are cranked up like crazy with microphones right down the performer's throats, that's the live event.
Any good home audio system sounds better than that. So we've come around full circle where it…
Atkinson: There's always the danger that, in an industry driven by the image, audio will take a back seat. "Well, we only need so much data space for the audio...it's only audio, who cares?" But when you experience a good Home Theater setup, what impresses you is not the picture, it's the way the sound drags you into the experience.
Federici: I've always been disturbed by the poor marketing that we've all done of audio. We've allowed "virtual reality" to be defined as something that isn't even close. The closest thing to a virtual-reality industry is the audio industry...We come closer…