Review from Sterophile August 1, 1976
Speaking of the potential longevity of tube equipment, we are told that a lot of dealers, pushing solid-state components, have been telling customers that the supply of replacement tubes is due to start drying up in a few years and that prices for them will start climbing precipitously as a result. We asked several tube manufacturers about this, and while one admitted that their future plans would be predicated on US consumer demand, four informed us that they had not considered discontinuing tube manufacture and could not foresee doing so as long as the present demand for them continued! One pointed out that their biggest market for amplifying tubes was in Europe and Asia, and said they would continue making them even if sales in the US came to a virtual standstill. That does not sound to us like the incipient demise of the vacuum tube.
Conclusion
Unfortunately, the price of the D-150 is murderous. Perhaps now, Audio Research can rest on their laurels for long enough to see if they can match this kind of sound from amplifiers that some of us can afford to buy.
We must also point out that the D-150 has yet to prove its durability. It does run very cool—more so than many solid-state amplifiers—but only time will tell that story. We hope the story has a happy ending.
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