[negura]

It's very good you are finding it that way. I liked the original KGSSHV, a lot, but not completely. It was great, but I am pleased it could be improved to a net effect to the sound quality I am hearing. And foremost credit goes to the amazing and scalable design we have from KG and I feel on this iteration I will be struggling to find minuses. Well that is until I hear something even better I guess.

 

[spritzer]

These claims of a massive improvement with an increase in current in no way correlate to the data at hand or my own experience.  The circuit is completely linear down to about 2mA (or even slightly less) and we chose 5.5mA as there was no way to make the amp clip and it worked at +/-500V off of onboard heatsinks.  I've gone way past 14mA in testing and the change is subtle at best so by definition there is something horribly wrong if the amp magically gets better by leaps and bounds simply by running it harder. 

 

[paradoxper]

  Ok my story. It's been a while since I received my build of the KGSSHV. Built by headinclouds it was an offboard 10mA 1800V. It was a exceptional experience working with Geoff (headinclouds) to get this build completed to my requirement. To the standard build we have added a 41 steps attenuator (credit to paradoxper for the idea) and Furutech XLR and mains sockets. Whether or not the later made any difference I don't know, but they seem to be quality built.
 
I had a good impression on the KGSSHV sound on my own headphones from previous listening. The initial impression after burn-in was right on par with my original experience. The KGSSHV is an amazing technically sounding amplifier, with great PRAT, detail and speed. However, having heard a few things here and there, I told Geoff something was yet missing. Yes I admit, I am a bit of an ass, I was so lucky in the first place to have found someone to build me a top spec KGSSHV and to my specific requirement.
 
So here's where the story goes a few months later. A few modifications, and most importantly since we have some good cooling capacity here, a 14mA current KGSSHV. 
 
I was expecting an improvement I will admit to that. It only has a couple of days burn-in, but I only needed about a few seconds to tell this is now a completely different animal. Before posting complete impressions I would like to allow it to settle to a complete run-in, but it is the best I have ever heard the Stax headphones yet. Organic, effortless, holographic, yet very detailed and fast. That thing that made the KGSSHV just a bit sterile is completely gone now.

What were the few modifications? Just doesn't seem like blasting the output is going to yield these significant changes alone. Though I guess we all hear differently
this just doesn't add up.

 

[NoPants]

In general upping the current seems to work primarily on the high end, making everything less fatiguing to listen to for long periods of time. This is the main difference I've noticed between a Megatron and offboard KGSSHV, and other differences are mostly in presentation.

 

[paradoxper]

Uh, yea, I guess Negura could have found the HV fatiguing. I spoke to someone who has gone way past 14mA and confirmed it's a subtle change. 

 

[negura]

  In general upping the current seems to work primarily on the high end, making everything less fatiguing to listen to for long periods of time. This is the main difference I've noticed between a Megatron and offboard KGSSHV, and other differences are mostly in presentation.

 
Yup. That's exactly what I noticed regarding the high-end of the spectrum. No longer the SR-007s are trying to sound as slightly something else, but I guess this is also a matter of preference. They sound determined, defined, energetic, but organic and sweet. Yet they sound more transparent and life like. Do I like the SR-007s better than before? Hell yeah, but that's me.
 
Exactly for this reason now the other good news: the KGSSHV will also better match with the SR-009s. Again imo.
 
The KGSSHV + SR007s was in no way fatiguing. It just sounds better now. In regards to your other question Cory: To get a final tune on the sound I think people should feel free experimenting with resistors, if they can, and this is as much as I want to comment on this, because this is both controversial and very much down to preference, and not a single blanket suits all. Not going to get into any arguments on this topic.

 

[preproman]

Was having a similar build done and was going to bias it as high as the builder would let me, was going to use the RK50 pot and lots of upgraded parts.  The builder called it the KGSSHV-DX.......The DX stands for Deluxe as the enclosure was going to be custom made.
 
This is the closest I got to my amp being built -->
 

 
 
I got ripped off by none other than Lil Knight himself - in the amount of $4K  Where the heck is my amp?
 
So I've gone forward and purchased the BHSE.  That was my SR-009 money...

 

[negura]

That is so not cool. I was also recently ripped off in audio, fortunately for me for a much lesser amount, but I know how it feels like. I also happen to have heard mentions of other people in the same situation as you with the same builder.
 
I'm sure you would've been very pleased with a unique KGSSHV like that, but the BHSE is you know... the benchmark. And there's nothing anywhere close to that look and feel.

 

[MacedonianHero]

  These claims of a massive improvement with an increase in current in no way correlate to the data at hand or my own experience.  The circuit is completely linear down to about 2mA (or even slightly less) and we chose 5.5mA as there was no way to make the amp clip and it worked at +/-500V off of onboard heatsinks.  I've gone way past 14mA in testing and the change is subtle at best so by definition there is something horribly wrong if the amp magically gets better by leaps and bounds simply by running it harder. 

Thanks Birgir....kinda what I expected. Interesting, I didn't realize that the 450V version could go as high as 14mA (mine is set to 9-10mA). 

 

[paradoxper]

  Was having a similar build done and was going to bias it as high as the builder would let me, was going to use the RK50 pot and lots of upgraded parts.  The builder called it the KGSSHV-DX.......The DX stands for Deluxe as the enclosure was going to be custom made.
 
This is the closest I got to my amp being built -->
 
 
 
I got ripped off by none other than Lil Knight himself - in the amount of $4K  Where the heck is my amp?
 
So I've gone forward and purchased the BHSE.  That was my SR-009 money...

Over at the other place it was confirmed that Tran ran into some issues with his CNC guy. Though his communication stinks don't lose all hope just yet.

 

[paradoxper]

  Thanks Birgir....kinda what I expected. Interesting, I didn't realize that the 450V version could go as high as 14mA (mine is set to 9-10mA). 

Yup. Birgir told me the same thing.

 

[spritzer]

  Thanks Birgir....kinda what I expected. Interesting, I didn't realize that the 450V version could go as high as 14mA (mine is set to 9-10mA). 

 
IXYS or Sanyo only applies to the third stage CCS.  It's not really a good idea to mess with the current setting on that one so what we alter is the output stage standing power. 

 

[gilency]

Exaggerations in sound improvement are not usually made by the DIY crowd.
I listen to the KGSSHV pretty much nightly and it sounds just great. Neither sterile nor digital or strident comes to mind.
Can't wait for the Megatron build so I can compare.
Building them is as much fun as listening....

 

[headinclouds]

There is some speculation on what caused the change to negura’s enjoyment of his KGSShv.  When I made it for him I used  the same circuit components, circuit boards and wiring types as the other three of this design I have built.  (Except at his request it had Furutech IEC socket and xlr connectors.)  It  sounded effectively  the same and  was running at the same nominal 450v and 10mA. 
negura asked if I had any ideas to squeeze a bit more out of it and the mix now includes metal film and tantalum film resistor types, the bias current has been increased to 14mA. The tantalum film resistors are used in the feedback and output of the amp.
When it was first powered up I was surprised that it seemed to be so different.  It was bright and revealing of detail.  The sound changes as the circuit runs in.   The amp seems very musically engaging to me also.

 

[Radio_head]

  Was having a similar build done and was going to bias it as high as the builder would let me, was going to use the RK50 pot and lots of upgraded parts.  The builder called it the KGSSHV-DX.......The DX stands for Deluxe as the enclosure was going to be custom made.
 
This is the closest I got to my amp being built -->
 

 
 
I got ripped off by none other than Lil Knight himself - in the amount of $4K  Where the heck is my amp?
 
So I've gone forward and purchased the BHSE.  That was my SR-009 money...

I would certainly hope that's not the case, as he currently has thousands of other peoples money tied up in T2 casework.  Last I heard he was waiting for the Chinese new year to pass so he could get some work done...