Blue Hawaii Special Edition

[justin]

yes, perhaps blue foam is needed

[purk]

So the third batch is nearly done then.  Nice!!  I love my BHSE!

 

Can we have sample pics of the new PSU chassis?

Edited July 30, 2013 by purk

[johnwmclean]

I bought a new quad of these:

http://www.elecdol.com/index.php/product-2/6ca7el34/

They are basically treasures re-labelled, supposedly with better test parameters, who knows....

Anyway I’m getting 350V offset over both channels, balance is around 50V.

 

My regular JJs which work fine.

 

Can I safely assume these tubes are fucked?

[justin]

would be weird if all the tubes were bad. check and see if maybe they installed the base wrong? if the filaments light up then it is correct. are the pins the right size for your sockets?

[johnwmclean]

Filaments lit up on all 4 tubes.

Pins fit the sockets.

Turning the bias pot doesn’t bring down voltage.

They physically look flawless.

 

I agree it is a little weird that all 4 tubes would be acting up.

[dsavitsk]

Since other tubes work in the amp, build a test rig. You need a high voltage, a heater supply, and a couple of resistors to see if the tubes behave as expected elsewhere.

[johnwmclean]

Thanks Doug that is a great idea, but at the moment I have the opportunity to return for refund, so I’ll think I take that option while still available.

 

I’ve bought a quad of NOS SED Winged C, I’ll give them a crack and see if they are to my liking as the new production Chinese tubes have me less than enthused.

[shellylh]

So, it seems that BHSEs may start shipping soon.    I'm thinking of getting a quad of matched SED Winged C EL-34 for now.  I know that the NOS Mullard XF2 are supposed to be better but I just don't have the time or money for the hunt right now.   Any reason I should just stick with the stock for now and/or get something else (that isn't $$$$).  

 

http://www.upscaleaudio.com/svetlana-sed-winged-c-el34/

 

Also, any links/words of wisdom about biasing when changing tubes?  

 

Is there a better place to buy from besides upscale audio (I don't know anything about them)?  What about:

 

http://www.amazon.com/Winged-EL34-Vacuum-Tube-Matched/dp/B004I4HI6I

 

http://www.thetubestore.com/Tubes/EL34-6CA7-Tube-Types/Winged-C-SED-EL34

Edited March 20, 2014 by shellylh

[justin]

i have a youtube video with instructions on adjusting it, but you probably dont need to do it unless its a very different kind of EL34/not really an EL34

[shellylh]

That's good to know. 

 

Also, found the you tube video, thanks. 

[shellylh]

Should the tubes be matched pairs or a matched quad and how much does a well matched pair/quad actually matter?

[luvdunhill]

Matched pairs. If you buy from Upscale you will probably get a close quad as they work from a decent inventory.

[Torpedo]

Shelly, I wouldn't purchase SED tubes at this point. I've learned, after seeing a tube of a SED quartet dying on my BH and causing some damages which needed specialist care, that they're not in production anymore. Some quartets or pairs being sold as matched, are just put-togethers from leftovers.

Considering I've had the chance to compare the SED and the JJs, I'd recommend you getting a good matched quad of JJ. Matched pairs also will do great, settings are completely separate for both channels.

[justin]

I had 1 new quad used them at a meet and 1 tube died

Sent from my iPhone using Tapatalk

[Torpedo]

I had 1 new quad used them at a meet and 1 tube died

Sent from my iPhone using Tapatalk

JJs or SEDs?

[luvdunhill]

Every one has some issue with some tube vendors. JJ to me seems the worst though. The Winged-C at Upscale are the older ones though, IIRC.

Edited March 21, 2014 by luvdunhill

[postjack]

congrats on making innerfidelity's amp wall of fame.

[Torpedo]

Every one has some issue with some tube vendors. JJ to me seems the worst though. The Winged-C at Upscale are the older ones though, IIRC.

JJ had a drop in production quality about six years ago, but they seem to have improved in the last couple of years. For some time I relied more on Chinese tubes than on the JJ, so go figure. My recent experience is being good so far.

[spritzer]

I never had any problems with my 10+ year old SED's but something might be off with the more recent production.  The JJ's are excellent and the new production Mullard's seem to be solid as well. 

 

The real "problem" with the BH circuit is that tube failure can be very bad news indeed. 

[luvdunhill]

How electrically do tubes die? What is open and what is short?

[purk]

I never had any problems with my 10+ year old SED's but something might be off with the more recent production.  The JJ's are excellent and the new production Mullard's seem to be solid as well. 

 

The real "problem" with the BH circuit is that tube failure can be very bad news indeed. 

 

Can you be more specific on the problems Birgir?  Had the treasure tube failed once on the BHSE and luckily everything is still fine.  OTOH, turning my KGSSHV on right after the BHSE did blow the fuse on the BHSE though.

[spritzer]

In a "normal" tube amp you have the signal entering on the grid with the cathode and anode loaded with resistors or chokes.  If the tube shorts then too much current is passed and the resistors burn up.  None of that applies here...

 

Personally I'd never use a Shuguang tube in any of my gear.  Hell I'd rather use my "made in USSR" tubes instead... 

 

How electrically do tubes die? What is open and what is short?

 

Good question.  Not sure what happened to this one but the heater died so I'm guessing it shorted to the cathode as the mosfets all lost their magic smoke.  

[johnwmclean]

I ran a quad of the Psvane EL34PH’s (from ebay) for a while, all four rattled mechanically, I sent them back, the sound was amazing though.

I’d have to agree with the hype presented over on head fi, maybe Grand Fidelity would be a better quality supplier... I don’t know.

Running a quad of SED’s at the moment, they are nice, not Psvane EL34PH territory though.  

[purk]

I ran a quad of the Psvane EL34PH’s (from ebay) for a while, all four rattled mechanically, I sent them back, the sound was amazing though.

I’d have to agree with the hype presented over on head fi, maybe Grand Fidelity would be a better quality supplier... I don’t know.

Running a quad of SED’s at the moment, they are nice, not Psvane EL34PH territory though.  

 

Maybe you should try the original Mullard either the Xf2 or 4.  I was running the treasure tubes on mine and thought it was good but then I made a switch to the Original NOS Mullards and I'm not going back.  The Psvane is trying its best to replicate the original Mullard EL34s from what I understand.

[HeadphoneAddict]

I've been running Mullard XF2 but I have a backup set of winged-C that you guys and scared me out of using in the future.