The BHSE is not self-biasing and it would be great if Justin would put the video on that process back up!

I use single “O” getter XF2s, and so far of the 4 tube types I have tried these sound the best. Are you indicating that Justin has made NOS XF2s available as an option with your BHSE order?

I have only done 4 tube swaps on the BHSE, but in every instance several volts needed to be adjusted out, most of it after the first 10 minutes. The follow-up adjustment at 2 hours usually involved getting the last volt to zero or close to it.

That is all but the adjustment part of a bias adjustment:wink:. I do an adjustment at about the 10 minute mark to make sure nothing is off by multiple volts, then again at two hours to dial everything in. When I did this last set of XF2s, the next day they were within .1 volts of zero on a check.

Long time BHSE owner. Trust Justin. He can be slow to respond, but does the right thing ultimately. I was the early owner that had problems with the BHSE after using it with KT-77s, really good ones at that. Justin had the unit for 6 months, but got it squared away and returned it while also...

I would order natural cotton when available.

I get that.  But in the old days,  Marantz Model 9s and 8bs, in every instance where I have used vintage KT77s instead of EL-34s the improvements were consistent and the choice of tube never an issue.  There are numerous articles from the period that indicate they are drop in replacements.  But...

These are not Russian or Chinese copies of KT77s. They are the real deal.  But I am not taking a chance.  Justin seems fine with 6CA7s.  But I am going to end up with some original EL-34 XF2s if I can find a good quad.

Unclear what the cause of the fault was.  I had gone back to the Big Bottle GE 6CA7s to listen to differences.  Shortly thereafter, the right warm up light would not come on and output became non-existent.  I waited for Justin to open a spot in his schedule and shipped the amp out.  He never...

Justin,   Please respond to my PMs and e-mail about the status of the repair of my BHSE.     JHellow

Justin:   Any diagnosis on what is wrong with the BHSE I sent back to you in May?   Thanks,   JHellow

I made my first tube change since I received the BHSE from Justin 18 months ago. I am running the unit with GE Big Bottles, 6CA7s. A very nice matched quad, that was a little low in output but very quite and I thought very transparent, while a bit light in the bottom end. But I was very...

Thermal management has a huge impact on component life.  As the owner of a Rappaport Amp One, which used quality components and sounded great when it was functioning, even the best components fail faster in a high heat environment.  The PSU on the BHSE does not have the Rappaport level of...

The PSU gets pretty warm.  It needs good ventilation.  

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