[Chris J]

It's not really a 'shock', it's a very mild tingling or vibrating feeling.
Many people report this for example when they touch their PC case when it's not grounded.
The problem with the house wiring in many old houses is that there is no ground wire, at least here in the Netherlands. See here the common type of socket we have without ground (scroll down): http://en.wikipedia.org/wiki/Schuko
If equipment is designed to be connected to grounded sockets, this can lead to the slight problem mentioned. I know this 'should not' happen, but it does quite often.

That's just a low voltage electrical shock.
Better hope your Stax amp with the 500 Volt bias voltage doesn't fail and create a ground fault.

 

[milosz]

Quote:

Nope, definitely not sealed

Really?  Drivers are not within dust seals?

 

[kevin gilmore]

there are outside dust seals on both sides but not hermetic in any way.
multiple air holes between the inside chambers and the outside.
just one look at the diaphrams from a household where people smoke
will confirm. contaminants get in their fairly easily.

 

[Michgelsen]

I know, but what can you do about it if you rent a place without grounded sockets? The landlord is certainly not having an electrician rewire the house. Best thing I can think of next is ground the system via radiator or water pipes, which I did, after I measured that they indeed seem to be grounded. This is not really how it's supposed to be done, but alas.
 
Safety is not really a problem because of the residual current device and circuit breakers. I agree it would be best to have grounded sockets everywhere, as is now mandatory in new installations (AFAIK).
 
 
Quote:

That's just a low voltage electrical shock.
Better hope your Stax amp with the 500 Volt bias voltage doesn't fail and create a ground fault.

 

[kevin gilmore]

The best ground if you don't have the real thing is a cold water pipe.
everything else including steam pipes may have pipe dope.

 

[spritzer]

Quote:

Great, do you like it?
I had a chance to try out the 2050 system friday, and I found it to be a great combo. Definitely a bargain at second hand prices. The SR-202 was a bit better out of my SRM-717 than out of the SRM-252II, but not by so much that such an upgrade would be worth the money IMO.
 

 
The 207 does sound ok off the BHSE too... 

 
Quote:

Thanks, that should more than take care of the side facing the grill. How about the side facing the ears? I imagine given the lack of a nylon film there this area is a no-go and I'll have to either live with those debris or buy new elements.
 
I remember reading some complaints about the HE60's dust protection from you earlier -- is this representative of the problem?

 
The problem is more with dust inside the drivers where they will cause real damage.  This is just cosmetic. 
 
Quote:

KGSSHV SUCCESSOR
 
Am I wrong in the impression that the DIY electrostatic amp scene is really quiet, with no PCBs currently being produced for designs from the last 5 or so years?
 
Is there a successor to the KGSSHV on the way?  I assume it would largely remain unchanged with a few subs for obsolete parts and the changes that would entail?
 
I'm finding that my new O2 MK1 (earliest version) needs a little more juice than the SRM 007T can provide; even though it still sounds awesome

 
There is no successor planned and I don't see the need for one.  We have altered the design a bit this year but it was simply a response to parts availability not a redesign in any way.  We also shrunk the boards a bit to make it easier to find chassis for the amps and added a servo option to the outputs to deal with the natural drift in the IXYS parts.  Most recently we did a simpler version of the PSU which is more similar to the one used in the old Blue Hawaii unit.  This is purely done as a cheaper option and because it's nice to have something like this around.  There have been some build issues with the power supplies as the ground plane is so close to the parts so this has been fixed too. 
 
This is all a bit new to us though as normally we just design, do a layout and then move onto something else.  We want to keep the HV alive though so constant rework is needed as the semiconductor companies try their darnedest to shut us down. 

   Any other new designs would be something simpler so a new poor mans amp design but who knows when that will be. 
 
Most of the time is spent now catching up on other projects or coming up with crazier and crazier stuff.  There are also some dynamic amps... 
 
Quote:

So it's a 2.1mm by 5.5mm connector just like all of the other connectors I have? Sweet.

 
This is the one and many of these supplies have plug on connectors which means you can reverse the polarity without any cutting/soldering. 
 
Quote:

Really?  Drivers are not within dust seals?

 
If they were truly sealed then we wouldn't have all the humidity based issues such as channel imbalance. 

 

[Chris J]

I know, but what can you do about it if you rent a place without grounded sockets? The landlord is certainly not having an electrician rewire the house. Best thing I can think of next is ground the system via radiator or water pipes, which I did, after I measured that they indeed seem to be grounded. This is not really how it's supposed to be done, but alas.
 
Safety is not really a problem because of the residual current device and circuit breakers. I agree it would be best to have grounded sockets everywhere, as is now mandatory in new installations (AFAIK).
 
 

 
Circuit breakers are for overcurrent protection. They may not protect you if your case becomes energized with 500 Vdc. Residual current devices do not always work if the system is not grounded properly. I have seen them fail to operate in poorly grounded systems. Cold water pipes are not always grounded, what if part of the water piping system is PVC?

 

[mechgamer123]

5mm not 5.5mm.

Oh well, I ordered it anyway...
If it doesn't fit, I'll cut the end off from the Japanese plug and use that...

KGSSHV SUCCESSOR

Am I wrong in the impression that the DIY electrostatic amp scene is really quiet, with no PCBs currently being produced for designs from the last 5 or so years?

Is there a successor to the KGSSHV on the way?  I assume it would largely remain unchanged with a few subs for obsolete parts and the changes that would entail?

I'm finding that my new O2 MK1 (earliest version) needs a little more juice than the SRM 007T can provide; even though it still sounds awesome

There is no successor planned and I don't see the need for one.  We have altered the design a bit this year but it was simply a response to parts availability not a redesign in any way.  We also shrunk the boards a bit to make it easier to find chassis for the amps and added a servo option to the outputs to deal with the natural drift in the IXYS parts.  Most recently we did a simpler version of the PSU which is more similar to the one used in the old Blue Hawaii unit.  This is purely done as a cheaper option and because it's nice to have something like this around.  There have been some build issues with the power supplies as the ground plane is so close to the parts so this has been fixed too. 

This is all a bit new to us though as normally we just design, do a layout and then move onto something else.  We want to keep the HV alive though so constant rework is needed as the semiconductor companies try their darnedest to shut us down.     Any other new designs would be something simpler so a new poor mans amp design but who knows when that will be. 

Most of the time is spent now catching up on other projects or coming up with crazier and crazier stuff.  There are also some dynamic amps... 

So it's a 2.1mm by 5.5mm connector just like all of the other connectors I have? Sweet.

This is the one and many of these supplies have plug on connectors which means you can reverse the polarity without any cutting/soldering. 

So, quick question: how much would one of those "budget" KGSSHV amps cost for all the parts? I like doing various DIY projects from time to time...

How would I got about reversing the polarity without doing any cutting and re-soldering?

 

[Warpkitty]

By way of some background I picked the Jameco wall wart for you because it was the same spec (power, barrel size,) as what this guy ordered:
 
http://www.head-fi.org/t/447175/stax-2050a-srm-252-information
 
Jameco changed their part numbers, but I looked at both data sheets and they were basically the same:
 
http://datasheet.octopart.com/DDU120050M2260-Jameco-Reliapro-datasheet-13550860.pdf

 

[Michgelsen]

I am aware of that and appreciate your concern (really), but I see no alternative in my case. The equipment is not faulty.
 
Quote:

Circuit breakers are for overcurrent protection.They may not protect you if your case becomes energized with 500 Vdc.Residual current devices do not always work if the system is not grounded properly. I have seen them fail to operate in poorly grounded systems.Cold water pipes are not always grounded, what if part of the water piping system is PVC?

 

[ultimanium]

I recently got some sr-202s, and some of the rear foam is missing.
Is this a problem that I should try to fix?
Perhaps put some cloth over it?

How hard is it to open up, and is it possible to order more inner foam?
I didn't see it on staxusa.



Thanks for any help.

 

[spritzer]

Quote:

So, quick question: how much would one of those "budget" KGSSHV amps cost for all the parts? I like doing various DIY projects from time to time...

How would I got about reversing the polarity without doing any cutting and re-soldering?

 
No way to give an accurate price on something like this, way too many variables but it's north of 500$. 
 
Either the end can be adjusted or you can use a special adapter to do the change. 

 

[Hun7er]

@spritzer : do you build a KGSSHV ?

 

[DefQon]

I recently got some sr-202s, and some of the rear foam is missing.
Is this a problem that I should try to fix?
Perhaps put some cloth over it?

How hard is it to open up, and is it possible to order more inner foam?
I didn't see it on staxusa.



Thanks for any help.

My SR-202 has the same side of the foam deterioration going on and it doesn't affect the sound. I'd leave it as is or you go via two ways of fixing it.

1. Buy a replacement pair from StaxUSA for around $30.
2. Source a supplier for 10ppi (pores per inch) reticulated foam.

 

[grokit]

My Lambda Pro has that deterioration, the consensus seems to be to leave it alone as it's just cosmetic, you could easily do more harm than good if you mess with it.