Schematic for Frank Cooter's amp

[recstar24]

I remember reading in a post somewhere that Frank was nice enough to release his schematic for his DHT amp, the dynamic version not the electrostat version. I would like to take a look at it. I'll send him a PM at headfi as well.

[screaming oranges]

Oh no no no no.

Don't start this now.

I had just finished convincing myself that a BHSE AND a Balancing Act is my end-all.

Please post that the information will be released in 2012 or something. And that only shitty-looking enclosures can accommodate the guts.

Thanks.

I graciously and gratefully await your reaffirmation.

[penger]

We should also see who would like to build one.

[matt fury]

WANT

[n_maher]

Whoever builds it had better be pretty damn talented if they want to take on that mercury vapor tube power supply. That thing is no joke and not simple and considerably different than typical tube rectified supplies.

[screaming oranges]

Whoever builds it had better be pretty damn talented if they want to take on that mercury vapor tube power supply. That thing is no joke and not simple and considerably different than typical tube rectified supplies.

Yes. That settles it. Everyone leave it alone. There are things not meant for man to tamper with.

Mercury poisoning - Wikipedia, the free encyclopedia

I am glad this has been settled.

The last amp of mercury...

...is in captivity.

The galaxy ...

...is at peace.

[tyrion]

I'll build it, I'm pretty damn talented to take on that mercury vapor tube power supply. That thing is no joke and not simple and considerably different than typical tube rectified supplies.

Wow, Nate just volunteered.

[Beefy]

Mercury poisoning - Wikipedia, the free encyclopedia

I can't actually imagine that they are that dangerous. Mercury vapour is pretty innocuous compared to organic mercury compounds. I'd be more worried about being hit by a bus on the way to work.

[screaming oranges]

Whoever builds it had better be pretty damn talented if they want to take on that mercury vapor tube power supply. That thing is no joke and not simple and considerably different than typical tube rectified supplies.

[dsavitsk]

So long as you don't drop them, they are fine. The biggest issue is that the mercury condensates and settles over time, so the first time you turn them on, you have to just power the filament and let them sit for a while (~30 minutes or so I think) to re-evaporate the vapor. There is also the issue of PS input caps, and they are really meant for choke input supplies. Choke input supplies are fine, but they are more expensive to implement and often hum unless you really oversize the choke. They also glow real pretty.

That said, I won't use them. Other than the light show, there isn't any real benefit to them (if you can hear the difference from one rectifier to another, you have a poorly designed power supply ...) and while the risk is small, it is there and I prefer to keep the toxins out of my living room when I can. I have broken enough tubes in my life to not want to deal with it.

Other things that may expose you to mercury ...

[n_maher]

It's not the mercury that I'm afraid of, it's the additional headache that goes along with using them. I remember reading an post by Frank in I think the Simple Stat Amp thread where he described the steps necessary to implement them. I further discussed this with him at CanJam and somewhere in the discussion was a "I don't know why it works but it does" statement from Frank. At that point I figured that if the designer couldn't explain it (even if he really understood it) I had no business getting anywhere near it. I'm a "known good" type of guy and the 5U4 works just fine for me thanks.

[matt fury]

We can cut the mercury vapor psu, as cool as it is. So what's the next excuse I can eliminate?

[kevin gilmore]

I'll add it to the list of things to make circuit boards for...

As soon as the schematic shows up.

Really this is going to be way simple.....

Compared to the T2.

[spritzer]

Compared to the T2.

Why do I have the feeling that this applies to most amp layouts...

[Dusty Chalk]

We can cut the mercury vapor psu...

Yeah, really. I mean, I realize that the power supply has a lot to do with how good an amp is, but it's only part of the equation...just substitute a different -- albeit at the same level of quality -- power supply.

[kevin gilmore]

Actually the thing is that mercury rectifiers are a much stiffer and lower impedance

device with much less voltage across them. That is why you use them. Its not

the same thing. Otherwise you might as well use sand for the rectifiers...

[matt fury]

Dr. G, are you saying that we cannot adequately substitute for the mercury?

[kevin gilmore]

hydrogen thyratrons used as synchronous rectifiers are even better.

Besides which they really light up purty.

Of course you can substitute parts. But where is the fun in that.

It may turn out that frank is using a much higher B+ (like 800 to 1200 volts)

in which case the mercury rectifiers will actually be necessary.

Pretty sure i heard that the electrostatic amp had a 1500 volt B+.

In which case you do have to pay attention when you build stuff like this.

[spritzer]

Pretty sure i heard that the electrostatic amp had a 1500 volt B+.

Ouch!!!!!

[Sherwood]

Ah, man, once you get above the point of "glue your withered husk permanently to the nearest path to ground", higher B+ voltages are just numbers

[matt fury]

<kirk> COOOOOOOOOTTTTTTEEEEEERRRRRRRRRRRR!!!!! </kirk>

[spritzer]

Ah, man, once you get above the point of "glue your withered husk permanently to the nearest path to ground", higher B+ voltages are just numbers

Not when you have to find caps to work at those voltages. Then there is the issue of most resistors only being rated for 500v etc.

I must say though that the thought of a single ended SS electrostatic amp with a transformer on the back does intrigue me quite a bit.

[guzziguy]

Not when you have to find caps to work at those voltages. Then there is the issue of most resistors only being rated for 500v etc.

Just put them in parallel.

[cetoole]

Just put them in series.

FIFY

[guzziguy]

Or both.