[astrostar59]

  oh well, looks like the BHSE died on me the other day .
 
Was working fine the whole day before. Switched it on again next morning, it shut off after the high voltage goes into the tubes (~1min on).
 
Switched the tubes today, tried to power it on, the left led did not light up, I quickly aborted.
 
Have not heard from Justin since it happened, I guess I am out of amp with weeks / months ahead ( …

Hi Arnaud
I am so sorry to hear this has happened. I also experienced some issues with my 300B Monoblock amplifiers for my speakers system. Basically a valve can burn out, burn up or blow as in the structure of the frame or the wires themselves can fall after failure and cause a short. In final power stages a valve can carry over 400 volts, so even a momentary short can cause the current to overload the stage in the power amp. Depending on the design of the amp various resistors will burn out and break the circuit. This is preferable to holding a short and causing more damage upstream. I would guess a resistor or two will be black and broken. The amp will need to be checked for other damaged parts, and the cause ascertained i.e. if a valve is ok, is the amp a complete board may be required.
 
On my 300B Monoblocks, I had a 300B short for long enough to blow the final PCB and it needed a new output board. That amp was single ended so open to damage, i.e. no protection at all other than resistors that blow and act like a fuse. This is the love / hate relationship I had with valve amplifiers. I ended up selling my Monoblocks and going Solid Stare Class A. I still have a DAC and a pre-amplifier that has tubes but in those cases the voltages are tiny and the tubes last years as in 3-5+. 
 
I am sure Justin will sort it. I think he had another customer last year under warranty period and it was sorted quite quickly.
 
Going back to valve failures, I think NOS are better than new issues IMO, as long as the NOS valves are from a genuine supplier and test good i.e. low use.
 
Hope this helps.

 

[astrostar59]

Just had a thought, does the BHSE have 2 fuses i.e one per side? If yes, you may find one has blown on switch on. I remember reading some users of the BHSE had to buy a 2A instead of a 1.5A. On switch on there will be a surge of mains power and it can cause a mains fuse to blow.
 
Other question, did the offending EL34 side light up or over glow on switch on?

 

[justin w.]

I emailed him last night. The filaments, which are just AC powered, are not lighting up. From a picture he sent me:
 

 
 
my guess is this is the problem and that no power is getting past the ac input. no idea what happened..

 

[kevin gilmore]

sure looks like an overheated iec input block due to bad connection between those pins
and the power cable. i have seen this before on other equipment usually 220v because the
bad connection causes arcing which overheats the pin in a hurry. my guess is that the
power cord also looks bad.

try another power cord and see what happens.

 

[astrostar59]

  I emailed him last night. The filaments, which are just AC powered, are not lighting up. From a picture he sent me:
 

 
 
my guess is this is the problem and that no power is getting past the ac input. no idea what happened..

I would check the fuse before you try again with a new mains lead. I had some 'fancy' mains leads but the weight of the oversized shrouds made the plugs sag and I sold them. Basically you need a light mains lead and support the lead on the back of your rack. If it strains on the pins it may arch and cause heat / issues. The fit should also be nice and tight.

 

[Bonesy Jonesy]

  Assembly continues on the next batch
 

Hi Justin,
What is the current delivery / lead time on the BHSE from you receiving the deposit for a 230V UK delivery in silver ? 

 

[Phil95]

 
I would check the fuse before you try again with a new mains lead. I had some 'fancy' mains leads but the weight of the oversized shrouds made the plugs sag and I sold them. Basically you need a light mains lead and support the lead on the back of your rack. If it strains on the pins it may arch and cause heat / issues. The fit should also be nice and tight.

 
You're perfectly right, Astrostar! I recommend using my patented "Las Vegas" cable support system (see picture).
 

 

[Sabenza]

Hi Justin,
 
I would also like to know the delivery/ lead time for your BHSE (to time various upgrades and purchases).  I sent you two emails over the last two weeks (maybe went into your junk mail box).  Thanks.

 

[astrostar59]

 
Hi Justin,
 
I would also like to know the delivery/ lead time for your BHSE (to time various upgrades and purchases).  I sent you two emails over the last two weeks (maybe went into your junk mail box).  Thanks.

No chance you will not get a solid time on that. Read this forum as see. Basically if you want this (amazing) Stat amp, you will have to stand behind everyone else. It is worth it IMO. 

 

[astrostar59]

   
You're perfectly right, Astrostar! I recommend using my patented "Las Vegas" cable support system (see picture).
 

Hey, like that. Are you marketing them locally or can I Paypal you?

 

[wink]

Dicey......!

 

[statfi]

sure looks like an overheated iec input block due to bad connection between those pins
and the power cable. i have seen this before on other equipment usually 220v because the
bad connection causes arcing which overheats the pin in a hurry. my guess is that the
power cord also looks bad.

try another power cord and see what happens.

Astrostar,  
 
I would be interested to see a picture of your IEC connector on the power cord, as Kevin suggests.  Does it have visible damage from arcing or whatever?
 
What mains voltage are you using?
 
Have you checked the fuses in the IEC socket?  (My post #7436 of 7481 is vaguely related.)

 

[astrostar59]

Hi Statfi
I think you mean Arnauld? He has the damaged BHSE, I was responding with ideas.

 

[icebear]

I've had the exact same issue with a plug from a washing machine. Due to vibration in the wall the plug was slowly moving out from the wall socket and the main fuse for the room tripped fortuntely before a fire could start but both the plug and the hot pole of the outlet showed signs of smoldering. So pretty sure loose contact can lead to this problem. And then consequently the fuse might have blown, too to prevent further damage - hopefully.
 
Some overly heavy garden hose type of power cords might obviously do more harm than good

.

 

[arnaud]

Thank you for the advice everyone. It turns out the power is basic "hospital grade" cord and I can't really see any damage to it. Working with justin to replace in the input block as voltage does not get past the iec connector, with hopefully no damage down the line...