spritzer

I could use that HE90 box to make mine complete but hell no at that price.

The audio grade transformers are already shielded so not a whole lot of benefits to be gained from the can. Looks real to me.

Just so it is clear, this PSU is exactly the same as the other one I did. Kevin just wanted to move it to the same layout architecture we use for all other boards so we drew it. Ohh and everything changes for us. There is nothing set in stone so constant improvements. I've lost count of how many revisions there are of the KGSSHV boards, at least 60 minor ones and almost 20 major ones.

It's quite cramped, that's how. Here is the latest version: Only major change is the voltage selector PCB which makes the AC wiring all neat and tidy. Nearly every centimeter is used now and I'm up to 9 pcb's per amp. The bigger changes are outside as I changed the layout a bit from the one above: It's very hard to photograph the chassis as it's so reflective... Thanks for the offer but I do have a Wordpress site up and running but it appears to be down now. My friend hosts it and he's been having some issues due to some of the other stuff being hosted there. It's mjolnir-audio.com and .net when ever it is up again. Haven't done a whole lot with it yet but I need to add all the DIY stuff and what stuff I have in stock.

http://www.pricejapan.com/front/e_good_info.php?code=996&category=10 That makes the amp practically free...

The 207 is still a bit on the bright side but nothing like the 307/407/507 so it's the one I'd pick. They are easy to find on ebay as a part of the SRS-2170 system. The small Stax amp included isn't the best but it's quite good for the price. All the systems on ebay are 100V but it uses as normal 12V/1000mA adapter but with the polarity reversed. It's easy to find a 230V unit and simply reverse the output plug to fit the Stax amp. 323S plus the 207 would be my choice but the Chinese KGSS will be better once it it fixed. I'll start a new thread when the KGSS gets here and I start to rip it apart.

The GES would only be a good match to the 407 as the 407 is pretty much horrid. Even the 207 is better let alone the older Stax models. The GES is a fine amp if you can get an old one cheap but I wouldn't buy new. The Chinese KGSS will need major work before it will work properly. Some components are run right on the limit while the volume control simply needs to be replaced. My amp has hit customs so you can expect some pics on how to fix it next week. The 006t isn't my favorite amp so perhaps try the 323S and the 727. The 727 is pretty bad in stock configuration but once modified it is quite nice.

This really isn't your typical tube amp, that's for sure. The tubes are used in the same way as you'd use a transistor. Just as a heads up, prototype boards for the KGDT have been ordered so things are moving forward there as well.

That's a lot of S's....

That would be nice if the bloody thing would fit in the chassis. Well they have a minimum order of 800$ so you cant' just buy one or two. Shipping is on the astronomical scale and the transformers are cheaper but not a whole lot so when you set them strict requirements.

The cathode sits at -400V which is well above the heater to cathode limit. Most "normal tube amps " (as in designs as old as the hills) have grounded cathodes so this is less of an issue.

No tubes and nothing is set in stone as of yet except that it won't have tubes. We can call it a mix between the KGSSHV and the KGST.

If you want to run it at +/-400V then you need 325-335VAC rails. 280VAC for +/-350V. For current 110mA is sufficient but I'd shoot for 140-150mA to be on the safe side. 30-36VCT is about 500mA. Heater windings should not be CT as they have -400VDC floating on them. You have to have two heaters or you will have massive problems so one for each board. 1.5A is more than enough to account for the variables in the tubes. No soft start for me as I simply don't think it is needed. The tube won't arc at these low voltages.

I've had two SumR self destruct and it ain't pretty. Speaking of transformers, seems Keen Ocean didn't quite get my requirements. The one in the middle should be about the same size as the ones on the left... KGST transformer on the far right, each weighs a whopping 3.3KG...

Are you running 10M90's at 500V in the KGST? That's not the best of plans...

The plus side is also how cheap it is to build and everything is in current production. No SMD parts either as the voltage is low enough to use KSA1156's and Antek transformers will work perfectly. A pair of ECC99's is about 35$, 12BH7's less than that and 6N6pi's way less than that. I also bought some parts to try a KGST with current made tubes.

It's also hard to be negative about anything if you lack the basic brain activity to understand any of this. I think it is the true mark of stupidity. It doesn't even work in Icelandic where word order is pretty much free.

The real problem are the tubes as not many can handle more than 300V. Push them hard and it all falls apart... The only dual I can think of that is rated for 500V is the 6CM7 but it's a dissimilar triode so not suitable for something like this. That said some of the computer tubes and TV tubes were meant to handle 600V peaks (or even higher) so they might fair well. The amp features switchable heaters on the board for 6.3V so either pin4 and 5 or pin4+5 and 9 for the 12V units. It also has switchable CCS so the current can be lowered with a jumper for tubes that can handle less power. Right now the list of tubes this one can use is : ECC99, 12BH7, 6N6pi, 6CG7/6FQ7, E182CC, 6840, 6350 and 5687. Should be more out there...

Thanks everyone!! Spent the day working on a new version of the KGST amp.

I'm going to go through my archives to see if there is anything to add to the list.

It's crazy so I like it.

That would work but you have to leave enough of the 10M90 hidden as the tab is live. Personally I'd just place the 10M90 on an external sink of some sort.

Simply using the chassis won't be enough. Add some thick aluminum plates as heatspeaders and then some heatsinks will work. Something inline with this: You can use internal heatsinks if there is enough airflow for them to function properly. There are no chassis like this so you need to fabricate everything.

It's not a sunrise as it never went down in the first place. Here is the odd bit, we are so used to this that our natural clocks aren't knocked off balance. Since we have the reverse effect in December we can't rely on daylight as some barometer of what time it is. This comes with being raised here but my friend from CT is still not used to this after 6 years.

I really doubt that the phones arrived like that but it could be a Monday unit or the assembler had just done 100 Sigma's (as the driver there is facing this way). For glue you can use good double sided carpet tape, the type that doesn't leave any residue. Tesa makes some nice stuff plus a bunch of other manufacturers.