Audio Research LS28SE vs McIntosh C53

I have heard Audio Research has reduced their backlog to less than a month. 

Although changing tubes is not a hazardous process. 

OP,

Tube problems happen, but are rare. I now run over fifty tubes and have not had any problems for years. I had one whistle a few years ago. I just brought out my backup set and replaced one by one until the whistle disappeared. 

Tubes are outside the control of the manufacturer. And as I say, generally are very reliable. I just recommend, replacing the other couple tubes... to rest your mind... and you'll probably never experience a problem in your life. I know other folks (that own a LS28SE and other ARC) and have never had a problem. 

I find AI does a pretty good job of contrasting sound:

The McIntosh C53 and Audio Research LS28SE offer distinct sonic signatures. The McIntosh is known for its slightly more mid-rangey sound with a noticeable lack of treble detail, while the Audio Research is described as more detailed and punchy across the entire frequency spectrum, with a particularly strong high-end. Some listeners find the Audio Research to be more "effortless" and revealing of the full sonic landscape. 

McIntosh C53:

• Sound Signature: Characterized as slightly mid-rangey and lacking in treble detail. 
• Overall Impression: Some describe the C53 as "well-behaved" and offering "fantastic sound quality" for its price point, according to a review by McIntosh. 
• Strengths: May be preferred by listeners who appreciate a warmer, more forgiving sound signature, especially those who may be sensitive to bright highs. 

Audio Research LS28SE:

• Sound Signature:

  Described as more detailed, punchy, and having a wider frequency response, particularly in the treble region. 

• Overall Impression:

  Often praised for its refined and textured sound, with a particular focus on clarity and transparency in the higher frequencies. 

• Strengths:

  May be preferred by listeners who value a more neutral and detailed sound, with strong imaging and separation. 

In Summary:

The choice between the two depends on personal preference. If you prioritize a warmer, slightly less demanding sound with good mids, the McIntosh C53 might be suitable. If you prefer a more detailed, punchy, and neutral sound with excellent high-end extension, the Audio Research LS28SE might be the better choice. 

The Audio Research is more evenly balanced with more detail. The Mac is a bit weightier sound. Definitely a preference thing. I would definitely listen to the Mac. My personal preference is definitely Audio Research. But there are lots of folks that like the Mac sound. Especially if rock music is your preferred fare. Also, if you have B&W speakers or Focal that have a hot top end, that can balance out the sound from Mac.