[98664c3yijh]

hi gang!
 
since the BH has been mentioned,  i've been thinking of
building one for my own use.
in the light of the commercial product, is DIY'ing BH still permitted?
Kevin?
if so, would appreciate pointing me to threads discussing the
DIY construction. sorry for boring you with that but
the forms search just outputs thousands of therads...
Is there a DIY version with less unobtainable
HV transistors?
 
thanks!!

 

[kevin gilmore]

diy's of the BH definitely permitted.
 
boards may still be available in the group buy thread, i have not been
paying attention.
http://www.head-fi.org/forum/thread/442065/group-buy-blue-hawaii-pcbs-and-jacks
 
generally the idea is to replace the 2sk389 with either lsk389's or matched 2sk170's
and to replace the pnp current sources with the 10m90s ixys current source parts.
 
i've never really done a howto for doing the assembly of these things, i'm expecting
people to figure out that on their own. Although there are and will be lots of pictures
of the new stuff. (T2, KGSSHV,KGITSOJC...)
 
In fact anyone can make boards for any of my designs. I just don't want another
occurance of the trevornetwork disaster.

 

[98664c3yijh]

 
Quote:

diy's of the BH definitely permitted.
 
boards may still be available in the group buy thread, i have not been
paying attention.
http://www.head-fi.org/forum/thread/442065/group-buy-blue-hawaii-pcbs-and-jacks
 
generally the idea is to replace the 2sk389 with either lsk389's or matched 2sk170's
and to replace the pnp current sources with the 10m90s ixys current source parts.
 
i've never really done a howto for doing the assembly of these things, i'm expecting
people to figure out that on their own. Although there are and will be lots of pictures
of the new stuff. (T2, KGSSHV,KGITSOJC...)
 
In fact anyone can make boards for any of my designs. I just don't want another
occurance of the trevornetwork disaster.

 
kevin, thank you!
pcb is not a problem, i can order them locally at a fair price.
please excuse my moronity, but
is there any updated schematics of the amp/PSU available, incorporating the
changes you mention? (i have moderate experience with tubes,
including transmitting ones, but no exp. with sand )
do i understand correctly that the power supply shown here
http://gilmore2.chem.northwestern.edu/projects/showfile.php?file=gilmore4_prj.htm
is common for both channels?
thanks!!
 
 

 

 

[kevin gilmore]

There is no updated schematic for the BH.  One of these days.
Maybe after i finally finish the electrostatic portable.
 
The old power supply definitely works great.
But these days i would use the kgsshv supply with 2 resistors
changed to lower the voltage to +/-400. You could probably push
it to +/-425 but the limiting factor is the 900 volt current source.
 
The one power supply runs both channels.

 

[98664c3yijh]

thank you kevin!
 
to all BH DIYers out there: is there
a compendium of knowledge on how to build the
beast?
 
thanks!

 

[J-Pak]

Excellent an electrostatic portable, this is why I love being an Omega 2 owner

 

[LeonWho]

I just got my first electrostatic setup!
 
It's a Stax SR-Lambda Pro with a Stax SRM-1 MKII.
 
However, I have a problem.
 
Every time there's bass, the left side of the Lambda Pro emits a heavily distorted rumble. The right side of the Lambda Pro is unaffected, and all other frequencies come through perfectly on both sides.
 
What's going on? Is there a way to fix this?
 
Thanks,
Leon

 

[Henerenry]

Try shorting the pins with your finger, then try leaving them plugged in and the amp on for a while...
 
Most likely though the driver may be on the fritz...

 

[LeonWho]

Quote:

Try shorting the pins with your finger, then try leaving them plugged in and the amp on for a while...
 
Most likely though the driver may be on the fritz...

Hmm, I've discharged and recharged the headphones several times already. Looks like I'll need a new pair of Stax headphones. 

 
Any other ways to fix them?

 

[edstrelow]

Are you sure it's the phones and not the amp?  You need either another Stax phones or amp to properly figure this out. It's even possible there is a problem with the connectors in the ear cup or the cable. 
 
I would take the drivers out and visually compare the good one vs the bad one to see if the bad one is damaged, possibly with a hole or even with dirt between a stator and the membrane.  
 
If it's an uncorrectible driver problem you probably want 2 replacements from Yamasinc.  An e-mail will usually get their response. They don't pick up the phone.  You will probably get a newer model driver. 

 

[Henerenry]

Hmmm, as mentioned on the other site, it could be as simple as the glue on one of the drivers coming unstuck.
 
Might pay to open them as edstrelow suggests.
 
One other thing you might want to try is to switch the left and right inputs on your amp, it will help determine if its the headphones or the amp.
 
For the record I had a pair that had similar symptons to yours although noticably one channel was quitier than the other, turned one of my drivers did die.
 
Hopefully all works well.

 

[gilency]

My Sigma Pro leather headband is very stretched and needs to be replaced. Can I use the same as the Lambda models? any of them? If not, any ideas? Both ends are overly stretched and getting pretty thin.

 

[GreenLeo]

We may assume that the KGSSHV should outperform the KGSS right?  May we assume that the KGSSHV will be on a par with the BH?

 

[kevin gilmore]

you can assume anything you want 

 
there will be BHSE's and the T2 at CJ.
 
you are going to have to wait a while to hear the KGSSHV
 
likely next year at CJ.
probably earlier.
 

 

[98664c3yijh]

Is BHSE schematics publicly available for DIYers too?
It seems to use less sand as the current source.
Thanks!