Audio Research GS 150 or REF 75SE?

Get the best of both with an ARC REF150 or REF150SE :)

To the best of my knowledge the GS-which stood for a rather short-lived "Galileo Series"-150 IS a Ref 150SE with different casework and meters but no functional difference. 

The new Ref series including the Ref 160S and 80S borrowed much of the clamshell casework of the GS series with new "Ghost Meters", triple layer circuit boards and other circuit changes. 

I am the original owner of a Ref 150SE and a Ref80S. I have had a hard time "cottoning up" to the Ref80S. It just leaves me cold. The Ref 150SE sounds better and I am willing to bet that the Ref 75SE sounds better too. ARC imho simply adopted the old approach of building a half-as-much-power version of the Ref160S which I have no doubt sounds amazing, and something got lost or F'ed up in the process. 

@ghdprentice "Characteristics: The REF 75SE is often described as having a warm and inviting sound with excellent dynamicsand soundstaging. It's also noted for its auto bias feature and pentode/triode mode switch."

I own the Ref 75SE it does not have an auto bias feature nor a pentode/triode switch. The 80S has those features.

 

@ghdprentice "Characteristics: The REF 75SE is often described as having a warm and inviting sound with excellent dynamicsand soundstaging. It’s also noted for its auto bias feature and pentode/triode mode switch."

I own the Ref 75SE it does not have an auto bias feature nor a pentode/triode switch. The 80S has those features.

Correct. The S series also ushered in better onrush current limiting to greatly decrease the chance of blowing tubes upon turning on the amp. My Ref 150 SE has blown tubes upon turning on the amp twice and the second time was in the throes of Covid where ARC had stopped taking in amps for repair due to their backlog in getting gear repaired. With the 150 SE out of service temporarily I opted to buy the 80S thinking it would be more reliable, flexible, and fun.

The 80S is more reliable imo, is arguably more flexible with its switchable pentode/triode modes, but not more fun. My Devore O/93’s are efficient enough in my smallish listening room to theoretically display the positive attributes of triode operation. I can’t imagine anyone preferring triode mode long-term with the 80S. It is a feature without a true benefit and I can’t help but wonder if somewhere along the line in implementing the changes ARC lost track of ultimate SQ with the 80S.

I am keeping my 80S as my backup amp. I have read quite a few posts in which former and present 80S owners have expressed the same sentiments as mine. I have NEVER read a post on an audio board in which an 80S owner was raving about their amp. But those Ghost Meters are sure something....

@welcher 

You are correct, The autobias and soft start are only on the most recent rendition of ARC amps.