Audio Research REF 75SE and REF 80S

[Fsonicsmith]

Having just sat down to put some more hours and listening in, it sounds petty to remark upon (as I listen to Tom Petty's "Wildflowers & All the Rest") but the user experience is entirely different between the two amps. With the 150 SE there is the rocker switch. It gets rocked and there is the sound of onrushing current as the transformer settles in.
Every time I rocked that button I feared for a KT150 to pop and instead the main fuse eventually blew with loud bang and a plume of smoke. With the 80S there is the same solenoid push button as the Ref 6's power button and you hear a satisfying click as the relay network initiates a two minute soft start/warm up. It not only matches the Ref 6 stylistically but functionally too. Silence. And with the click of that solenoid push button the large front panel lights up instantly. Very satisfying and very petty.
Tom Petty's voice today is more sonorous, more chesty and pleasantly nasal, more realistic than it was with the 150 SE but that is based on memory only and through a thick fog of new-equipment ownership bias. But last night I was not happy with another male voice-Warren Zevon's. This amp is unsettled.

 

[Fsonicsmith]

The Ref 80S continues to settle in and improve. This amp does not have the same authority over low end bass, the same macro dynamics (slam) of low bass that the Ref 150SE has. I suspect-but don't know-that its big brother Ref 160S does. It has its own set of attributes that rise above the 150SE though. Without any loss of detail it presents a more believable portrayal of the recording.
And I must mention that in response to the Roy Gregory "Bright Shining Lie" thread put up by Carlos, I played around with speaker positioning. I have had blue masking tape down on my heavy solid walnut flooring for years marking the optimum position of my Devore O/93's with the Ref 150SE after many hours of experimentation. I had never even considered that replacing the Ref 80S for the Ref 150 SE warranted experimenting with speaker placement again. I think I adjusted toe-in slightly previous to reading the thread but not by much and without much change.
This time I experimented with a wholesale change of speaker position, lifting each speaker up and away from the previous location. I had a suspicion that I needed to start with placement closer to the corners to get a bit more bass oomph without bloat. I did. I knew my former locations were a bit close (narrow) and moved each speaker a bit further away. I spent an hour using my old blue masking tape as a reference point for matching both loudspeakers relative to the old locations.
Some of you may laugh but my reference for speaker placement is the audio show cliche Dead Can Dance's "Into the Labyrinth" and the cliche first cut, "Yulunga". When Lisa Gerrard's raga drones sound just right, when the opening tablas and bongos sound real and in the room, and most of all, when the shakers about 90 seconds or so into the track sound like they are coming at you and then hovering in space (for all of one or two seconds) I know I am close. Moving my Devore O/93's further out laterally and closer to the front wall and corners accomplished this. "Yulunga", fwiw, sounds better now, a more accurate portrayal of what I believe to be on the recording, than I ever achieved with the Ref 150SE.
All of the above is in triode mode. After experimenting between the two I have decided that I prefer triode over pentode mode in my listening room with my gear.

 

[Jblesser]

Billion$Baby, I do not. I have only 85 hours on my 80S due to life getting in the way of listening. That said, I am making a concerted effort to listen more and put more hours on the amp. I have zero doubt that the 80S excels over the 150 SE in terms of the ultimate listening experience. I do not believe in "the absolute sound". I am in the late great Art Dudley school of "how does the music make me feel". That said, I do appreciate piano sounding like a piano, sudden sounds like a vocalist unexpectedly shouting from stage left or right creating a startle-response, the sound of an acoustic bass "appearing" as if in the room and I am getting all of those things already. I listened for three hours last night and the low end is firming up nicely where it was previously soft. In comparison, the 150 SE was/is drier and more analytical. The one thing the 150 SE did better was take an iron fisted grip on my woofers. The 80S is not, imo, "tube-y" but instead more fluid and a lot more fun. You can tell it is a very special amp and I have no doubt that the 160M and 160S provide even more of the same.

About to pickup my 80S from the dealer and wondering about your experience regarding stands and power cable for this unit. I plan to spend the breakin period with the included cable. I have a solid rack for the unit alongside my other equipment but am wondering if you have done any experimenting with any kind of stand, etc. Thank you very much in advance!

 

[Fsonicsmith]

I am using a.VH Audio PC, whatever was the top cable about five years ago. I see he has "flavors" now but don't recall that being the case when I ordered mine. Maybe I have just forgotten. I have not experimented with different PC's with this amp. I did with the 150SE and preferred the VH Audio. The amp sits on a four inch thick slab of maple butcher block. I tried five heavy duty IsoAcoustic pucks underneath and heard nothing positive so I took them out form. under. You can see my system on the AGon site.

 

[Fsonicsmith]

About to pickup my 80S from the dealer and wondering about your experience regarding stands and power cable for this unit. I plan to spend the breakin period with the included cable. I have a solid rack for the unit alongside my other equipment but am wondering if you have done any experimenting with any kind of stand, etc. Thank you very much in advance!

Any impressions yet? A trick question on my part. It will go in and out of phases for a good 200 hours. At about 150 hours I even started to have doubts and considered putting my Ref150SE back in my system. Have tons of patience. This is a great amp. Now at 250 hours I am hearing the best sound I have ever heard at home. I am very much in love with the SW1X DAC III B processing the streaming from an Aurender W20 with Qobuz too. It is my impression that getting the best of any tube amp requires a set of complimentary loudspeakers. The Devore O/93's meet that requirement with this amp. No doubt many others do as well.

 

[Jblesser]

Any impressions yet? A trick question on my part. It will go in and out of phases for a good 200 hours. At about 150 hours I even started to have doubts and considered putting my Ref150SE back in my system. Have tons of patience. This is a great amp. Now at 250 hours I am hearing the best sound I have ever heard at home. I am very much in love with the SW1X DAC III B processing the streaming from an Aurender W20 with Qobuz too. It is my impression that getting the best of any tube amp requires a set of complimentary loudspeakers. The Devore O/93's meet that requirement with this amp. No doubt many others do as well.

Thanks so much. My Klipsch Forte IVs are great but I have my eyes on the Devores. I want to hear them first but they are on the short list for sure. Thank you for taking the time to write this! ARC mentioned to me that I could run the amp with the speaker wires unattached for breaking in the unit if I want to minimize annoying my wonderful wife, so i am doing that for the first few days.

 

[charles1dad]

@Jblesser
“ARC mentioned to me that I could run the amp with the speaker wires unattached for breaking in the unit if I want to”

Really?
I thought with tube power amplifiers, the output transformer needed connection with a load. So, apparently this isn’t true for every tube amplifier. I wonder how ARC gets around this? No doubt it’s a very fine amplifier,
Charles

 

[Fsonicsmith]

Yes Charles1dad, I didn't think the Ref 80S can be fired up without a load BUT I just pulled out my manual and not a word is said in warning about making sure the loudspeakers are hooked up before firing up the amp so it appears Jblesser did not make this up Just the same, I am not going to test mine out with this practice.

 

[Argonaut]

ARC mentioned to me that I could run the amp with the speaker wires unattached for breaking in the unit if I want to

I would double check that there hasn’t been a misunderstanding here before running the amplifier without a load.

 

[charles1dad]

I would double check that there hasn’t been a misunderstanding here before running the amplifier without a load.

Agreed. Just to be on the safe side. No load with ARC amplifiers would be the exception to the rule if doing this is okay.
Charles