Has anybody heard the new Audio Research LS 27?

It does seem automotive technology has changed dramatically over the past 40 years, not so with linestage circuit designs. For those with money to spare, getting the lastest ARC then flipping it 3 years later for the latest ARC is fine -why not, does no harm and they are excellent linestages. But if money was an issue and you wanted to have a wonderful linestage you could easily buy a 20 year-old ARC preamp and be very much in the company of what any ARC preamp has to offer - a good sounding linestage - there simply has not been that much improvement or new knowledge of how to design a linestage - better part always helped, then and now.

I currently have a ARC line stage that I bought in 2000. I have never heard any of the newer line stages. Now I'm curious to take my line stage to an ARC dealer and compare it with the newer models.

Granted, there are not thousands of ways to amplify a signal. Circuits change when designers have the insight to use a SOTA device in a new way. In tube design it would be utilizing a new tube. The circuit topology has to change to take advantage of it. True you have less design options wih tube products then transistor. Bipolar transistors give way to j-fets at preamp inputs thereby lessening noise. Some of this is semantics. What is your definition of a circuit topology change? Are you aware of the fact that the way you lay the circuit board out, the circuit board material, and the thickness and width of the traces can make or break a potential design. It is true that if a designer finds that a particular circuit in a product like a power supply sounds particularly good, (yes power supplies do have a strong effect on an audio circuit), they might use it in another design. You have to remember that it's the whole package, not just individual parts or circuit topology that make up the sound of the unit your listening to. Some manufacturers actually remove or update parts as they become available after the first design because it sounds better or gives better reliability. That's not being cheap, that's improving performance and that would be a circuit topology change. In fact a new manufacturer of amplifiers has just come out with a new output transistor circuit that doesn't utilize emitter resistors. That to me is a new circuit design. I don't think someone like Nelson Pass or John Curl would say there had been little change in line stage design over the past 40 years. When new parts come out, circuits change. Everyone is entitled to their opinion.

I agree with what you say, to me it is a bit of the hyped up nature of things in this hobby, you would think this stuff sounds more real than real by now:) I think most of us can also agree that ARC has been making wonder tube preamps for a long time - they undoubtedly know what they are doing, whether they are you cup of tea or not the obvioulsy have made many listeners happy with their efforts.

I haven't heard an LS27 but I intend to buy one nonetheless , All indications are that it is a cost effective upgrade from my LS17 ( which incidentally I am perfectly happy with ), having not listened to anything else since I bought it .

Spirited discussion about ARC's constant upgrades etc has been going on since the late 1970's , so nothing has , or will , change .

I regard ARC as a value for money premium product .