Under the hood - Electrostatic amp photos

[Chefguru]

HIGH-AMP.DE Sirrah V3 - controversial
* hot glue use
* transformer sanded to fit chassis
* no insulation on mains plug
* cloth underneath pot to stop shorting
* transformer leads too close to input wires (no twisting)
* ballast resistor under rated for 600v
* design shows no CCS for VAS stage

 

[Chefguru]

HIGH-AMP.DE Polaris V1
(taken from website)
No Schematics posted. Hard to read the transistor parts

 

[Chefguru]

The Soren KGSShv looks great! Here's a circa 2010 KGSShv build with 500V IXYS parts and onboard heat sinks. DACT stepped attenuator (every time I see an Alps Blue in otherwise nice gear, I get antsy to replace it). Out of like 4 - 5 KGSShv variants I've heard, this one is easily my favorite. Very neutral. Pairs well with any headphone. It's the cheapest I've heard a 007 Mk 1 be "properly" driven. I'm not sure I'd pick even a BHSE over this one. And the sound you get with this amp paired to ES1a is just incredible for the money. Unfortunately the top cover has poor ventilation, and is powder coated to boot - so it has heat dissipation issues. You know what (can) happens when an electrostatic amp overheats? First you hear noise, then distortion. With top off it runs clean (yes, dangerous) and reliably all day. I need to get some holes / slots drilled in, or just re-case it.

I've read some interesting comments about these 500v KGSSHV builds. It's interesting since the Mjolnir carbon is built at 400v. It seems like the extra juice would just create heat issues and not really do much outside of increase the volume a few db.

@kevin gilmore what's your take on the extra v?

 

[kevin gilmore]

500v has more headroom before clipping. some people like it very loud. and the higher you go in voltage the more current you need.
the output transistors for the kgsshv are obsolete unless you happen to have a stock of them.

carbons are 450v max due to parts ratings. no way to increase the voltage with current production parts. which is why the felista amps at 500v blow up.

d&g is 750v and 40ma. the extra voltage requires the extra current.

 

[alota]

500v has more headroom before clipping. some people like it very loud. and the higher you go in voltage the more current you need.
the output transistors for the kgsshv are obsolete unless you happen to have a stock of them.

carbons are 450v max due to parts ratings. no way to increase the voltage with current production parts. which is why the felista amps at 500v blow up.

d&g is 750v and 40ma. the extra voltage requires the extra current.

d&g meaning Dolce & Gabbana?

 

[kevin gilmore]

david and goliath

 

[Daiyama]

Here are 2 photos of two other High-Amp Sirrah V3 amps. Just to add other examples to the photo which is always cited.
These photos are not mine and were provided by a fellow member of another message board, he has bought both amps directly from High-Amp and also owns an Alpha Centauri from High-Amp.

1.) Bought 08/2022, it was an offer, therefore either a pre-owned or remaining stock device, hence the little dust which can be seen. This amp has XLR in only.

2. Bought in 10/2022 as newly build. This amp has XLR and RCA in and additional as per request RCA out.

 

[icnaiwhimor1975]

T2

 

[Svperstar]

Sorry I guess I dropped my phone too many times and it's blurry unless you hold it super close

KGSSHV Carbon 2022 build

 

[headinclouds]

The first KG design I built finished in Jan2013. KGSShv onboard heatsinks. Just learning about them then.

 

[SolarCetacean]

Note: these pictures are a bit too tall for Head-Fi's inline picture formatting and look vertically squashed. Click on the pictures to see them at their correct aspect ratio.

SRM-727: I hadn't realized that it had a volume potentiometer bypass switch inside. It has board version 302.
It's a 100V unit, but the transformer seems to have all of the wires attached, so it might be possible to change the voltage.
Update: or maybe not. A look into old threads indicates that even if the exterior wires are all there, the bridging wires underneath the Stax logo might be cut. That requires more amp surgery to fix in order to change the voltage.

CCS-modded Stax SRM-006tS by Mjolnir Audio (spritzer) with custom transformer and my addition of RCA Clear Top tubes.
Note the CCS module and heatsink on the left.

Stock SRM-353x:

 

[Svperstar]

Now that I'm on an s24 Ultra not a s21 Ultra with a busted camera I should take more pics of my estat amps

 

[tumpux]

wait, I thought all electrostatic people shoots a z9..

 

[Aspirant Audiophile]

Has anyone convinced a builder (or someone who knows...stuff) to comment on the photos? I love this thread, love its potential for increased transparency. At the same time I wonder how many of us visitors know what we are looking at to a degree that helps buyers make wise choices. Me personally, I could point out a few transistors and wires here and there, but I wouldn't know why one amp is built one way versus another, or the cumulative effect.

Note: I'm not suggesting targeting any amps or builders in any critical fashion.

 

[paradoxper]

Has anyone convinced a builder (or someone who knows...stuff) to comment on the photos? I love this thread, love its potential for increased transparency. At the same time I wonder how many of us visitors know what we are looking at to a degree that helps buyers make wise choices. Me personally, I could point out a few transistors and wires here and there, but I wouldn't know why one amp is built one way versus another, or the cumulative effect.

Note: I'm not suggesting targeting any amps or builders in any critical fashion.

You take that discussion to Head-Case.